CN114924478A - Special vehicle rapid vehicle display cooperative control method - Google Patents

Abstract

The invention discloses a collaborative control method for rapid display of special vehicles, comprising steps: Step 1. In the process of collaborative display of special vehicles, various boundary conditions for the coordinated display of special vehicles are proposed; Step 2. Design of special vehicles based on interference compensation The coordinated leveling method of vehicles, and the coordinated leveling method of special vehicles based on interference compensation is used to control the coordinated display process of special vehicles; The vehicle coordinated erection method controls the coordinated display process of special vehicles, and completes the coordinated control of the rapid display of special vehicles. The coordinated control of the rapid display of special vehicles can effectively realize the rapid display of special vehicles, and has the characteristics of short display time, high leveling accuracy and fast erection speed.

Description

A collaborative control method for rapid display of special vehicles

technical field

The invention relates to the technical field of special vehicle control, in particular to a coordinated control method for rapid display of special vehicles.

Background technique

The exhibition process of special vehicles is an important part of the whole system preparation process. It is divided into two processes: leveling and erection. The length of the exhibition process directly affects the rapid response ability and survivability of a new type of special vehicle. The speed and accuracy will directly affect the actual effect of the operation; in order to reduce the preparation time before the operation of the special vehicle, the special vehicle is required to complete the leveling in a short time; the erection process is a process of changing loads, the system is prone to instability, and The instability of the system will cause the load structure and internal instruments to be subjected to excessive impact, so the erection process should try to avoid shocks, so it is necessary to plan the leveling and erection process to meet the requirements of rapidity, stability and safety;

At present, my country's new special vehicles have continuously shortened the preparation time by continuously simplifying the operation process, but there is still a certain gap with the demand for rapid exhibition vehicles; under this background, rapid exhibition vehicles have become a new generation of special vehicles. The key issue is to further compress the exhibition time of special vehicles, which is the only way to improve the rapid response capability;

With the development of all-electric special vehicles, the intelligent power unit of diesel engine + generator has become a trend. The traditional way of taking power from chassis engine and driving hydraulic leveling will be replaced by modular and integrated electric leveling cylinder; To achieve high-speed erection, it is necessary to use a hydraulic power system with large flow and high pressure, which will increase the installed power and volume of the system and bring difficulties to the equipment layout of special vehicles. To solve this problem, gas-liquid mixing can be used. Drive the system to reduce the installed power and volume of the system and improve the power density of the erection power system of the special vehicle; therefore, the use of electric drive leveling and gas-liquid hybrid drive erection has become a key technology to greatly improve the rapid response capability of special vehicles. It has become the key to carry out research on a new generation of fast show car technology integrating electric leveling and gas-liquid hybrid power;

At present, the following problems generally exist in the exhibition operation of special vehicles:

(1) For the leveling system of special vehicles, there are mainly problems in the following three aspects: First, hydraulic cylinders are often used for leveling of traditional special vehicles. Traditional hydraulic leveling has a relatively long existence time and relatively poor leveling accuracy. Second, in the leveling control algorithm, the traditional hydraulic cylinder leveling control mostly adopts the fuzzy PID control algorithm, but due to the nonlinearity of the hydraulic system, the time-varying parameters, the load difference of each actuator and other characteristics, there is a lack of control accuracy. The third is that the traditional special vehicle leveling system mostly adopts the overall plan of left and right leveling of the rear outriggers, and the leveling is completed in the order of lifting the car (four legs on the ground), leveling (left and right rear outriggers), and extending the front legs , the whole leveling process is serial, with many links and time-consuming, it is difficult to meet the requirements of rapid leveling;

(2) For the erection system of special vehicles, the load erection system of special vehicles mostly adopts three-joint fixed-point mechanism, and the traditional hydraulic erection system driven by quantitative pump is generally used; the traditional hydraulic erection system needs to achieve rapid erection, The volume and weight of the hydraulic oil source will increase significantly, which is not conducive to the development needs of light-loaded and low-installed power for special vehicles;

(3) For the exhibition process of special vehicles, the following three specific problems will occur in collaborative exhibition vehicles: First, when the vehicle is leveled and erected, the erecting hydraulic cylinder will be subjected to lateral moment, and there will be a danger of rollover. Therefore, it is necessary to analyze the actual situation; secondly, when the vehicle is erected, the leveling electric cylinder is subjected to the impact force generated by the erection process, which will affect the leveling accuracy, and will produce a larger radial pressure on the leveling hydraulic cylinder. The third is that the horizontal and vertical acceleration of the erecting hydraulic cylinder will become larger, and there is a risk of overloading;

To sum up, there is an urgent need to devise a collaborative control method for a rapid display of special vehicles to solve the above-mentioned problems in the prior art.

SUMMARY OF THE INVENTION

In view of the above-mentioned problems, the present invention aims to provide a coordinated control method for the rapid display of special vehicles. The method uses a coordinated leveling method for special vehicles based on interference compensation and a coordinated erection method for special vehicles based on high-voltage energy storage to control The coordinated control of the rapid display of special vehicles can effectively realize the rapid display of special vehicles, and has the characteristics of fast flattening speed and high leveling accuracy.

In order to achieve the above object, the technical scheme adopted in the present invention is as follows:

A collaborative control method for rapid vehicle exhibition of special vehicles, comprising the steps of

Step1. In the process of cooperative exhibition of special vehicles, put forward various boundary conditions for the cooperative exhibition movement of special vehicles, and plan the cooperative movement scheme of the special vehicle exhibition process according to the boundary conditions, and propose a cooperative exhibition mode of parallel work;

Step2. Design a coordinated leveling method for special vehicles based on interference compensation, and use the coordinated leveling method for special vehicles based on interference compensation to control the coordinated display process of special vehicles;

Step3. Design the coordinated erection method of special vehicles based on high-voltage energy storage, and use the coordinated erection method of special vehicles based on high-voltage energy storage to control the coordinated display process of special vehicles to complete the coordinated control of rapid vehicle display of special vehicles.

Preferably, the design process of the coordinated motion scheme described in Step 1 includes:

Step101. According to various boundary conditions in the process of cooperative exhibition of special vehicles, determine the coordinated exhibition scheme in which the leveling system and the erection system work at the same time;

Step102. On the basis of the special vehicle collaborative exhibition plan, analyze the leveling principle of four-point leveling, and use the three-point-by-height method to level the vehicle;

Step103. On the basis of the special vehicle collaborative exhibition plan, optimize the erection mechanism and design a rapid erection system solution.

Preferably, the analysis process of the four pivot point leveling described in Step 102 includes the following steps:

(1) The leveling of the system can be simplified as the leveling of a certain platform plane, and a dual-axis inclination sensor is installed in the two mutually perpendicular directions of X and Y of the platform to measure the horizontal inclination in two directions;

(2) Let the coordinate of the outrigger i in the horizontal coordinate system OX ₀ Y ₀ Z ₀ be ⁰ P _i =( ⁰ P _iX , ⁰ P _iY , ⁰ P _iZ ) ^T , in the platform coordinate system OX ₁ Y ₁ Z ₁ The coordinates in are ¹ P _i =( ¹ P _iX , ¹ P _iY , ¹ P _iZ ) ^T ; at the same time, it is assumed that the initial angles α and β of the platform are not 0, and the platforms are all small inclination angles, satisfying the condition that α and β are small angles , the transformation matrix between the two coordinate systems is obtained as follows:

各支点Z的坐标为：(3) Set in the coordinate system OX ₁ Y ₁ Z ₁ , the coordinates of each leg are: ¹ P _i =( ¹ X _i , ¹ Y _i , ¹ Z _i ) ^T ; then

The coordinates of each pivot point Z are:

⁰ Z _i =(-α,β,1)( ¹ X _i , ¹ Y _i , ¹ Z _i ) ^T

(4) Pre-support before leveling, first determine the highest point, and use this point as the origin of the coordinates, the initial position of each leg is:

⁰ Z _i = -α ¹ X _i +β ¹ Y _i + ¹ Z _i

Obviously, ¹ Z _i =0, therefore, the above formula can be expressed as:

⁰ Z _i =-α ¹ X _i +β ¹ Y _i

(5) Let i=h be the highest point, ⁰ Z _h ≥ ⁰ Z _i , then at any time, the position difference between each fulcrum and the highest point is:

e _i = ⁰ Z _h - ⁰ Z _i = -α( ¹ X _h - ¹ X _i )+β( ¹ Y _h - ¹ Y _i )

(6) The outriggers are symmetrically distributed along the front, rear, left and right sides of the frame. If the distance between the long sides of the outriggers is L _a and the distance between the short sides is L _b , the coordinates of the outriggers in the moving coordinate system are:

Based on this, the outriggers of each leg are calculated, and the positive and negative inclination angles obey the right-hand rule. According to the different combinations of positive and negative inclination angles in the X-axis and Y-axis directions, the corresponding outriggers with the highest coordinates are also different. The following are divided into four types. Situation Analysis:

(1) When α<0, β>0, the outrigger 1 is the highest:

(2) When α>0, β>0, the outrigger 2 is the highest,

(3) When α<0, β>0, the outrigger 3 is the highest,

(4) When α<0, β>0, the outrigger 4 is the highest,

According to the above four situations, it can be seen that the adjustment amount of each leg is 0 at each leveling time, ||αL _a ||, ||βL _b ||, ||αL _a ||+||βL _b || One of the four values is assigned according to different high points; the leveling process can be iterated repeatedly until the level reaches the requirements.

Preferably, the design process of the interference compensation-based coordinated leveling method for special vehicles described in Step 2 includes the following steps:

Step201. Take the electric cylinder as the leveling leg, and establish the electric cylinder deformation error model by calculating the theoretical error of the leveling process and calculating the theoretical bearing capacity of the leveling leg;

Step202. Introduce the leveling control strategy based on disturbance compensation in the electric cylinder deformation error model, take the deformation of the electric cylinder as the initial input error of the leveling controller, use the shape variable as the feedforward of the control system, and adopt the fuzzy PID control method Feedback control is carried out, and a coordinated leveling method for special vehicles based on interference compensation is obtained.

Preferably, the calculation process of the theoretical error of the leveling process described in Step 201 includes:

(1) In the planetary roller screw, let F ₀ be the axial force of the planetary roller screw, the force at each contact point is the same, F _n is the contact normal force, F _a is the axial force, F _t is the tangential force, F _r is the radial force, F _s is the resultant force of the axial force and the tangential force, λ is the lead angle of the roller; θ is the contact angle between the screw and the roller, and the nut and the roller ;

Then the relationship between the total axial force and the normal force of a single contact point is

where n is the number of rollers;

(2) According to the Hertz theory, the four principal curvatures of the point contact between the center screw and the roller are determined as:

In the formula, R is the arc radius at the contact point between the roller and the center screw; R ₁ is the radius of the thread raceway of the center screw; d ₁ is the radius from the contact point to the center screw; d ₂ is the contact point to the roller the radius of the column axis;

It can be seen that the curvature sum is:

∑ρ=ρ ₁₁ +ρ ₁₂ +ρ ₂₁ +ρ ₂₂

The principal curvature function is:

(3) According to the Hertzian contact theory, the elastic deformation of the contact surface is obtained as:

In the formula, E ₁ and E ₂ are the elastic moduli of the roller and the screw; μ ₁ and μ ₂ are the Poisson’s ratio of the roller and the screw, and F ₀ is the axial force.

Preferably, the process of calculating the theoretical bearing capacity of the leveling legs described in Step 201 includes:

(1) The axial force and radial force of the two front outriggers on the frame are respectively f _1y , f _1x and f _1z ; the axial force and radial force of the two rear outriggers on the frame are respectively f _2y , f 1x and f 1z f _2x , f _2z ; body pitch angle α, body roll angle β; the left and right span of the two front outriggers is h, and the span of the two rear outriggers is the same; the span of the front and rear outriggers on the same side is l; the frame mass is m ₁ , the load mass is m ₂ , and the total mass is m; the center of mass of the frame is located in the vertical symmetry plane of the car body, and the horizontal distance from the central axis of the rear leg is l ₁ ; The horizontal distance of the central axis of the leg is l ₂ ; the acceleration of gravity is g=9.8m/s ² ;

(2) Taking the frame plane as the benchmark, track the balance between the frame gravity and the axial force of the outriggers when the state of the body changes, and list the balance equation; the resultant force in the axial direction of the outriggers is equal to the frame and load gravity on the outriggers. Projection in the axial direction; when the vehicle body has both a pitch angle and a roll angle, the force balance equation is as follows:

f _1y +f _2y =mg cosαcosβ

f _1x +f _2x =mg sinα

f _1z +f _2z =mg sinβ

Taking the connecting line of the two front legs as the rotation axis, the moment balance analysis is carried out. The moment balance equation is as follows:

[m ₁ g(ll ₁ )+m ₂ g(ll ₂ )]cosαcosβ=f _2y l

Taking the connecting line of the two rear outriggers as the rotation axis, the moment balance analysis is carried out. The moment balance equation is as follows:

[m ₁ gl ₁ +m ₂ gl ₂ ]cosαcosβ=f _1y l.

Preferably, the leveling control strategy based on interference compensation described in Step 202 includes:

Step2021. Calculate the initial error as feedforward compensation, the feedback control adopts adaptive fuzzy PID control, the input error e of the fuzzy controller is obtained according to the feedforward interference compensation value, and then calculate the error rate of change e _c ;

Step2022. The fuzzy controller adjusts the values of ΔK _p , ΔK _I and ΔK _D by continuously updating _e and ec during operation, realizes online self-tuning of PID parameters, and meets the different requirements of different _e and ec for control parameters;

Among them, the fuzzy universes of the input and output linguistic variables e, e _c , ΔK _p , ΔK _I , and ΔK _D of the fuzzy controller are all [-6, 6], and the fuzzy subsets are [NB, NM, NS, ZO, PS, PM, PB], considering the coverage and sensitivity, stability and robustness of the universe, each fuzzy subset adopts a Gaussian membership function.

Preferably, the control process of the method for coordinated erection of special vehicles based on high-voltage energy storage described in Step 3 includes the following steps:

Step3011. Adopt the high-voltage accumulator to drive the rapid erection scheme of special vehicles, and establish the high-voltage accumulator;

Step3012. On the basis of the high-pressure accumulator, establish the mathematical model of the three-stage hydraulic cylinder;

Step3013. On the basis of the mathematical model of the three-stage hydraulic cylinder, establish the mathematical model of the buffer device.

Preferably, the process of establishing the mathematical model of the three-stage hydraulic cylinder described in Step 3012 includes:

(1) The positive and negative cavities of the hydraulic cylinder are regarded as a node cavity respectively, and the pressure equation of the two cavities is established by the node cavity method, the output force of the cylinders at each level is calculated, and the mathematical model of the three-stage cylinder is obtained as follows:

In the formula, E is the effective bulk elastic modulus of the oil; V _f and V _b are the initial volumes of the forward and reverse chambers of the multi-stage cylinder, respectively; Q _f and Q _b are the flow rates flowing into or out of the forward and reverse chambers, respectively; A _f3 , A _f2 , and A _f1 are the action areas of the _3rd , _2nd , and 1st-stage cylinder positive cavity respectively; _Ab3 , Ab2 , and Ab1 are the 3rd, 2nd, and 1st stage counter-cavity action areas respectively; l _3max , l _2max , l _1max is the maximum displacement of the 3rd, 2nd and 1st stage cylinders respectively; p _f and _pb are the pressures of the forward and reverse chambers of the oil cylinder respectively; x ₃₂ and v ₃₂ are the axial displacement and velocity of the 3rd stage cylinder relative to the 2nd stage cylinder respectively ; x ₂₁ , v ₂₁ are the axial displacement and velocity of the 2-stage cylinder relative to the 1-stage cylinder respectively; x _1p , v _1p are the axial displacement and velocity of the 1-stage cylinder relative to the piston rod; F ₃ , F ₂ , F ₁ is the output force of the 3rd, 2nd and 1st stage cylinders respectively; F _f3 , F _f2 , F _f1 are the frictional forces of the 3rd, 2nd and 1st stage cylinders during the operation respectively; F _p3 , F _p2 , F _p1 are 3, 2. The collision force between the first-stage cylinder and the piston rod;

(2) In equation (40), the friction model in the operation of the cylinder barrel adopts the improved LuGre model, and the mathematical model is as follows

where z is the average elastic deformation of the bristles; v is the relative velocity of the contact surface; σ _z is the stiffness coefficient; τ _z is the damping coefficient; η _z is the viscosity coefficient; v _s is the Stribeck velocity constant; F _c is the Coulomb Friction force; F _s is static friction force; h is oil film thickness;

(3) The hydraulic cylinder inter-stage collision model in Eq. (40) is based on the Hertzian contact force model, and its mathematical model is as follows

where K _p and K _n are the equivalent spring stiffness; μ is the hysteresis factor; δ is the normal penetration depth of the contact point; v _R and _vc are the speeds of the two cylinders; x is the relative displacement between the cylinders; g _p is the upper bound of cylinder displacement; g _n is the lower bound of cylinder displacement.

The beneficial effects of the present invention are as follows: a special vehicle rapid exhibition vehicle collaborative control method, compared with the prior art, the improvement of the present invention is:

(1) The present invention designs a coordinated control method for a rapid exhibition vehicle of a special vehicle. Based on the design index of the rapid exhibition vehicle, the method completes the design and optimization of the electric leveling system and the high-voltage energy storage drive erection system and the design and optimization of key components , The analysis shows that the use of this collaborative vehicle exhibition scheme can shorten the exhibition time from 25s to 15s, and the time is shortened by 40%;

(2) This method proposes a leveling control method based on interference compensation, and conducts simulation and experimental research on two working conditions of large inclination angle leveling and small inclination angle leveling; simulation and experimental results show that the proposed control method can control the adjustment The leveling system completes the leveling within 10s, the leveling accuracy of the pitch angle is below 0.05°, the leveling accuracy of the roll angle is below 0.002°, the leveling accuracy is high, and the results of the simulation and the experiment are basically consistent, which proves the simulation model. accuracy;

(3) This method proposes a coordinated erection method for special vehicles based on high-pressure energy storage. In view of the rapid erection requirements of special vehicles, a large-volume high-pressure accumulator is selected to reduce the installed power. The accumulator adopts a piston-type structure, which can be used in The effect of shortening the erection time is achieved by rapidly releasing energy under large loads; the multi-hole throttle device is used for the transition between the hydraulic cylinder stages, and the buffer device for erection in place is designed; the simulation and experimental results show that the designed erection system can be used in 15s. However, through the comparison between simulation and experiment, it can be found that there will be large vibration when the second and third stages of the erecting hydraulic cylinder are changed. The simulation results in the rest of the time period are in good agreement with the experimental results, which proves the accuracy of the simulation model. sex;

(4) This method analyzes the influence of the special vehicle's coordinated motion on the leveling and erection process, and establishes a coordinated motion simulation model according to the mechanical relationship between the erection mechanism and the leveling system. It affects the accuracy of the leveling process, which reduces the leveling accuracy by 0.003°, which is still within the allowable leveling accuracy range. The radial force of the leveling legs is checked. It meets the design requirements; it affects the acceleration of the center of gravity during the erection process, which will increase the acceleration of the center of gravity of the erected load. The results show that the acceleration in the horizontal and vertical directions is within 0.6g, which is less than the design index of 1g; the simulation results prove that the synergistic development feasibility of the car.

Description of drawings

FIG. 1 is an algorithm flow chart of the coordinated control method for rapid display of special vehicles according to the present invention.

FIG. 2 is a flow chart of the coordinated exhibition vehicle movement scheme according to Embodiment 2 of the present invention.

FIG. 3 is a coordinate relation diagram of a vehicle frame platform in Embodiment 2 of the present invention.

FIG. 4 is a schematic diagram of a leveling process according to Embodiment 2 of the present invention.

FIG. 5 is a structural diagram of a gas-liquid hybrid driving erection system in Embodiment 2 of the present invention.

FIG. 6 is a schematic diagram of a rapid erection system according to Embodiment 2 of the present invention.

FIG. 7 is a schematic diagram of the erecting structure of the multi-stage cylinder according to the second embodiment of the present invention.

FIG. 8 is a mechanical model diagram of a planetary roller screw according to Embodiment 3 of the present invention.

FIG. 9 is a diagram showing the force of a contact point in Embodiment 3 of the present invention.

FIG. 10 is a schematic diagram of the force in the initial state of leveling according to Embodiment 3 of the present invention.

FIG. 11 is a structural diagram of an adaptive fuzzy PID control based on interference compensation according to Embodiment 3 of the present invention.

FIG. 12 is a model diagram of the AMESim leveling leg according to Embodiment 3 of the present invention.

FIG. 13 is a model diagram of the AMESim leveling control system according to Embodiment 3 of the present invention.

FIG. 14 is an overall model diagram of the leveling system in Embodiment 3 of the present invention.

FIG. 15 is a simulation model diagram of a leveling controller in Embodiment 3 of the present invention.

FIG. 16 is a co-simulation model diagram under the MATLAB/Simulink environment according to Embodiment 3 of the present invention.

FIG. 17 is a simulation curve diagram of the displacement of the leveling outrigger adjusted by the small inclination angle according to Embodiment 3 of the present invention.

FIG. 18 is a physical view of the leveling outrigger according to Embodiment 3 of the present invention.

FIG. 19 is a block diagram showing the composition of the rapid leveling system according to Embodiment 3 of the present invention.

FIG. 20 is a schematic diagram of a leveling control system in Embodiment 3 of the present invention.

FIG. 21 is a graph showing the change curve of the leveling inclination angle and the displacement curve of the leveling outrigger according to Embodiment 3 of the present invention.

FIG. 22 is a comparison diagram of interference compensation control and fuzzy PID control in Embodiment 3 of the present invention.

FIG. 23 is a curve diagram of the simulation and experimental leveling deviation of the leveling legs according to Embodiment 3 of the present invention.

FIG. 24 is a diagram of a porous throttle buffer device according to Embodiment 4 of the present invention.

FIG. 25 is a model diagram of a three-stage hydraulic cylinder in Embodiment 4 of the present invention.

FIG. 26 is a schematic diagram of a new type of end-face-fitted buffer according to Embodiment 4 of the present invention.

FIG. 27 is a physical view of the cartridge valve block in Embodiment 4 of the present invention.

FIG. 28 is a schematic diagram of the erection control principle according to Embodiment 4 of the present invention.

FIG. 29 is a diagram of a vertical control panel according to Embodiment 4 of the present invention.

FIG. 30 is a diagram of an experimental prototype of a special vehicle in Embodiment 4 of the present invention.

FIG. 31 is a diagram showing the erection state of the experimental prototype of Example 4 of the present invention.

FIG. 32 is a comparison diagram of experiment and simulation in Example 4 of the present invention.

FIG. 33 is an analysis diagram of the vertical direction force of the erecting oil cylinder according to the fifth embodiment of the present invention.

Fig. 34 is an analysis diagram of the vertical direction force at the connection between the load and the chassis of the special vehicle according to the fifth embodiment of the present invention.

FIG. 35 is a diagram of a simulation model of coordinated motion of special vehicles in Embodiment 5 of the present invention.

Fig. 36 is a model diagram of the erecting hydraulic cylinder according to the fifth embodiment of the present invention.

FIG. 37 is a control signal diagram of a leveling system according to Embodiment 5 of the present invention.

FIG. 38 is a displacement diagram of the coordinated motion leveling outriggers according to Embodiment 5 of the present invention.

Fig. 39 is a displacement diagram of the hydraulic cylinders for coordinated movement and erection according to the fifth embodiment of the present invention.

FIG. 40 is a diagram showing the erection angle of the coordinated movement according to Embodiment 5 of the present invention.

FIG. 41 is a displacement deviation diagram of the coordinated motion leveling outriggers according to Embodiment 5 of the present invention.

FIG. 42 is a graph showing the erecting force of coordinated motion in Embodiment 5 of the present invention.

Fig. 43 is the force diagram of the leveling outrigger under the condition of large inclination angle according to the fifth embodiment of the present invention.

Fig. 44 is the force diagram of the leveling outrigger under the condition of small inclination angle according to the fifth embodiment of the present invention.

Fig. 45 is the radial force diagram of the leveling leg under the condition of large inclination according to the fifth embodiment of the present invention.

FIG. 46 is a comparison diagram of acceleration in the direction of the erection system of two motion modes according to Embodiment 5 of the present invention.

Among them: in Figure 10, Figure (a) is the force diagram of the special vehicle in the pitch-left state, and Figure (b) is the force diagram of the special vehicle in the pitch-right state;

In Figure 17, Figure (a) is the simulation curve of the displacement of the leveling outrigger under large inclination angle, and Figure (b) is the simulation curve of the displacement of the leveling outrigger under the small inclination angle;

In Figure 21, Figure (a) is the change curve of the leveling inclination angle when the large inclination angle is adjusted, Figure (b) is the change curve of the inclination angle when the small inclination angle is adjusted, and Figure (c) is the displacement curve of the leveling leg when the large inclination angle is adjusted. d) is the displacement curve diagram of the leveling outrigger adjusted at a small inclination angle;

In Figure 22, Figure (a) is a comparison diagram of the change in pitch angle under a small inclination angle, and Figure (b) is a comparison diagram of the change in the roll angle under a small inclination angle;

In Figure 23, Figure (a) is a graph of the simulation and experimental leveling deviation under large inclination angle conditions, and Figure (b) is a graph of simulation and experimental leveling deviation under small inclination angle conditions;

In Figure 32, Figure (a) is the variation curve of the vertical angle between the simulation and the experiment, and Figure (b) is the deviation curve of the vertical angle between the simulation and the experiment;

In Figure 38, Figure (a) is the displacement diagram of the leveling outrigger under the condition of large inclination during coordinated motion, and Figure (b) is the displacement diagram of the outrigger under the condition of small inclination under the coordinated motion;

In Figure 41, Figure (a) is the displacement deviation diagram of the leveling outrigger under the condition of large inclination angle during coordinated movement, and Figure (b) is the displacement deviation diagram of the outrigger under the condition of small inclination under the coordinated movement;

In Figure 46, Figure (a) is a comparison diagram of the acceleration in the horizontal direction of the two motion erection systems, and Figure (b) is a comparison diagram of the acceleration in the vertical direction of the two motion erection systems.

Detailed ways

In order to enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention are further described below with reference to the accompanying drawings and embodiments.

Embodiment 1: Referring to a kind of coordinated control method for rapid display of special vehicles shown in the accompanying drawings 1-46, it includes the steps:

Step1. In the process of collaborative exhibition of special vehicles, various boundary conditions of the coordinated exhibition movement of special vehicles are proposed, and the coordinated movement scheme of the special vehicle exhibition process is planned according to the boundary conditions, and a collaborative vehicle exhibition mode of parallel work is proposed at the same time;

Step2. Design a coordinated leveling method for special vehicles based on interference compensation, and use the coordinated leveling method for special vehicles based on interference compensation to control the coordinated display process of special vehicles;

Step3. Design the coordinated erection method of special vehicles based on high-voltage energy storage, and use the coordinated erection method of special vehicles based on high-voltage energy storage to control the coordinated display process of special vehicles to complete the coordinated control of rapid vehicle display of special vehicles;

Step 4. According to the mechanical relationship between the erection mechanism and the leveling system, a simulation model of coordinated motion is established, and the influence relationship between the variable load impact and the rapid display system of the special vehicle during the coordinated motion is determined.

Preferably, the design process of the coordinated motion scheme in the special vehicle exhibition process described in Step 1 includes:

Step101. According to various boundary conditions in the process of cooperative exhibition of special vehicles, design a coordinated exhibition scheme in which the leveling system and the erection system work at the same time;

Step102. On the basis of the coordinated exhibition plan for special vehicles, according to the leveling principle of four-pivot leveling, analyze the leveling principle of four-pivot leveling, and choose to use the three-point-by-height method to level the vehicle

Step1021. Design a leveling scheme based on four fulcrum leveling;

Step1022. On the basis of the leveling principle based on four pivot points, choose to use the three-point height-by-height method to level the vehicle;

Step103. On the basis of the special vehicle collaborative exhibition plan, optimize the erection mechanism and design a rapid erection system solution.

Preferably, the design process of the disturbance compensation-based leveling process control method described in Step 2 includes the following steps:

Step201. Use the electric cylinder as the leveling leg, and establish the electric cylinder deformation error model by calculating the theoretical error of the leveling process and calculating the theoretical bearing capacity of the leveling leg;

Step202. Introduce the leveling control strategy based on disturbance compensation in the electric cylinder deformation error model. By taking the deformation of the electric cylinder as the initial input error of the leveling controller and the shape variable as the feedforward of the control system, fuzzy PID control is adopted. The method performs feedback control and forms a coordinated leveling method for special vehicles based on disturbance compensation.

Preferably, the control process of the method for coordinated erecting of special vehicles based on high-voltage energy storage in Step 3 includes the following steps:

Step301. Adopt the high-voltage accumulator to drive the rapid erection scheme of special vehicles, and establish the high-voltage accumulator;

Step302. On the basis of the high-pressure accumulator, establish a mathematical model of a three-stage hydraulic cylinder;

Step303. On the basis of the mathematical model of the three-stage hydraulic cylinder, establish the mathematical model of the buffer device.

Embodiment 2: The design process of the coordinated motion scheme of the exhibition vehicle in the special vehicle exhibition process described in Step 1 includes:

Aiming at the problems of low driving efficiency and long exhibition time due to the traditional hydraulic serial drive method used by traditional special vehicles, a coordinated exhibition vehicle motion control scheme integrating high-voltage energy storage erection drive and electric drive leveling was proposed, and electric outriggers were developed. Design of structure, leveling system and high-voltage energy storage drive erection system, and optimization of erection mechanism, laying a foundation for the coordinated control analysis and experimental verification of exhibition vehicles;

Step101. Design a collaborative exhibition plan for special vehicles

According to the actual needs, a special vehicle collaborative exhibition plan is proposed, and the boundary conditions are set as:

(1) The all-electric leveling time is not more than 10s, the leveling accuracy is not more than 0.5°, and the single-leg radial force of the outrigger electric cylinder is not more than 14.7kN;

(2) The rapid erection time is not more than 15s;

(3) The stroke of the erecting hydraulic cylinder is not more than 5m, and the horizontal and vertical components of the acceleration of the center of gravity during the erection process are both less than 1g;

In order to further reduce the total time used for special vehicle exhibition vehicles, a leveling scheme is designed in which the leveling system and the erection system work at the same time, so that the total vehicle exhibition time is not more than 15s. The leveling process of this scheme is divided into three stages: the first stage In order to quickly extend the leveling legs with no load until they touch the ground, and at the same time the erection system performs the erection operation, the first stage and the second stage of the erection hydraulic cylinder are extended; the second stage is the leveling stage when the leveling legs touch the ground. , until the special vehicle is leveled, the erection cylinder is fully extended in the second stage at this stage, and the third stage is in the extending stage; the third stage is when the erection cylinder is extended in place, and the whole vehicle reaches a stable state; The flow chart of the car is shown in Figure 2;

By adopting the above-mentioned collaborative vehicle exhibition scheme, the exhibition time of special vehicles can be shortened from 25s for serial work to 15s for parallel work;

Step102. On the basis of the special vehicle collaborative exhibition scheme, design an electric leveling scheme that supports the above-mentioned flattening process. Step1021. Design a leveling scheme based on four-pivot leveling

(1) The leveling set in any system can be simplified as the leveling of a certain platform plane. According to the principle of "three points or two intersecting straight lines determine a plane", the essence of platform leveling is to make two intersecting lines on the platform. The straight line is adjusted to be level. For this purpose, a dual-axis inclination sensor is installed in the two mutually perpendicular directions of X and Y of the platform to measure the horizontal inclination in the two directions. The coordinate relationship is shown in Figure 3;

(2) Let the coordinate of the outrigger i in the horizontal coordinate system OX ₀ Y ₀ Z ₀ be ⁰ P _i =( ⁰ P _iX , ⁰ P _iY , ⁰ P _iZ ) ^T , in the platform coordinate system OX ₁ Y ₁ Z ₁ The coordinates in are ¹ P _i =( ¹ P _iX , ¹ P _iY , ¹ P _iZ ) ^T ; it is assumed that the initial angles α and β of the platform are not 0, and under normal circumstances, the platform is a small inclination angle, satisfying α and β as For the condition of small angle, according to the kinematics conclusion of spatial attitude transformation, the transformation matrix between the two coordinate systems is as follows:

于是各支点Z的坐标为：(3) Assuming that in the coordinate system OX ₁ Y ₁ Z ₁ , the coordinates of each leg are: ¹ P _i =( ¹ X _i , ¹ Y _i , ¹ Z _i ) ^T ; then

So the coordinates of each fulcrum Z are:

⁰ Z _i =(-α,β,1)( ¹ X _i , ¹ Y _i , ¹ Z _i ) ^T (2)

(4) Carry out pre-support before leveling, first determine the highest point, and use this point as the origin of the coordinates, then the initial position of each leg is:

⁰ Z _i = -α ¹ X _i +β ¹ Y _i + ¹ Z _i (3)

Obviously, ¹ Z _i =0, therefore, the above formula can be expressed as:

⁰ Z _i = -α ¹ X _i +β ¹ Y _i (4)

(5) Assuming i=h is the highest point, ⁰ Z _h ≥ ⁰ Z _i , then at any time, the position difference between each fulcrum and the highest point is:

e _i = ⁰ Z _h - ⁰ Z _i = -α( ¹ X _h - ¹ X _i )+β( ¹ Y _h - ¹ Y _i ) (5)

(6) The outriggers are symmetrically distributed along the front, rear, left and right sides of the frame. If the distance between the long sides of the outriggers is L _a and the distance between the short sides is L _b , the coordinates of the outriggers in the moving coordinate system are:

Based on this, the extension of each leg can be calculated, and the positive and negative inclination angles obey the right-hand rule, that is, from the coordinate vector end, counterclockwise rotation is positive, according to the different combinations of positive and negative inclination angles in the X-axis and Y-axis directions The corresponding outriggers with the highest coordinates are also different. The following four situations are analyzed:

(a) When α<0, β>0, the outrigger 1 is the highest:

(b) When α>0, β>0, the outrigger 2 is the highest,

(c) When α<0, β>0, the outrigger 3 is the highest,

(d) When α<0, β>0, the outrigger 4 is the highest,

According to the above four situations, it can be concluded that the adjustment amount of each leg is 0 during each leveling, ||αL _a ||, ||βL _b ||, ||αL _a ||+||βL _b || One of the four values, assigned according to different high points; the leveling process can be iterated repeatedly until the level reaches the requirements;

Step1022. On the basis of the leveling principle based on four-fulcrum leveling, design a four-fulcrum leveling scheme: In order to meet the requirement of rapid leveling within 10s, the leveling legs are arranged symmetrically along the body axis, and the leveling controller, Under the action of the inclination sensor, etc., after the four outriggers are detected in the ground contact leveling stage, the left and right leveling accuracy of the rear outriggers is the main control parameter. The electric cylinder with the stepless speed regulation function is used as a scheme in which the four outriggers act at the same time and are leveled in parallel, which saves the leveling time; since the outriggers are inconvenient to shorten during the electric leveling of special vehicles, the three-point-by-height method is used for leveling. The leveling process is shown in Figure 4;

Step103. On the basis of the special vehicle collaborative exhibition scheme, design a rapid erection system scheme

Step1031. Analyze the working principle of high-voltage accumulator-driven rapid erection

The rapid erection system driven by the high-pressure accumulator is shown in Figure 5. The rapid erection system takes power from the vehicle's own power source to drive the hydraulic pump to charge the high-pressure accumulator. The cavity is separated, and the liquid proportional reversing valve is opened during rapid erection, and the high-pressure liquid is quickly transported from the accumulator to the multi-stage hydraulic cylinder to achieve rapid erection. When the erection cylinder approaches the end position, the end buffer damper in the cylinder intervenes work to achieve deceleration; the principle of the gas-liquid hybrid drive system with the accumulator as the power source is shown in Figure 6;

According to the schematic diagram of the rapid erection system shown in Figure 6, it can be seen that the high-voltage accumulator and erection mechanism need to be modeled; the high-voltage accumulator needs to be mathematically modeled inside, and the erection mechanism is divided into three parts for modeling and analysis : First, the mathematical modeling of the three-stage erecting hydraulic cylinder, the second is to optimize the design of the erecting structure of the three hinge points, and the third is the mathematical modeling of the stage-changing buffer of the erecting hydraulic cylinder;

Step1032. Optimal design of erection mechanism

The erection process of the special vehicle is to change the load from the horizontal state to the vertical state. The erection structure usually adopts a three-joint structure. Because the special vehicle needs to be leveled before the erection, because the front and rear span of the vehicle is large, the leveling legs The stroke is limited, so it is necessary to compensate the leveling and pitching angle through the erection angle. According to this, the hydraulic cylinder can be erected to a maximum of 95°, and the stroke of the hydraulic cylinder is limited to be less than 5m when it is erected to 95°, and the installation distance is less than 3m , the maximum length of the load is 8m, and the initial erection force is greater than 130t, so it is necessary to optimize the design of the erection mechanism. The erection structure is shown in Figure 7;

The main design parameters of erecting mechanism are as follows:

(1) The distance between the load center of mass O ₃ and the rotation fulcrum O along the direction perpendicular to the load is L ₄ =1.1m;

(2) The distance between the load center of mass O ₃ and the rotation fulcrum O along the load direction is L ₅ =6.1m;

(3) Load mass m=32t;

(4) The acceleration of gravity is taken as g=9.8m/s ² ;

(5) The horizontal distance from the rotation fulcrum O to the lower fulcrum O ₂ of the vertical cylinder is L ₁ ;

(6) The distance from the rotation fulcrum O to the upper fulcrum O ₁ of the vertical cylinder along the load direction is L ₃ ;

(7) L ₁ and L ₃ are variable;

Selecting the load as the research object, the Euler dynamic equation of the load is:

Jθ” ₁ =FL ₃ sinθ ₄ -mgL ₆ cosθ ₃ (10)

The following geometric relationships exist in the erection mechanism,

θ ₃ =θ ₁ +θ ₂ (15)

Then formulas (19)-(23) are listed according to the boundary conditions of the erection mechanism:

3m≤L ₁ ≤8m (22)

3m≤L ₃ ≤8m (23)

Calculate the formulas (19)-(23), and the data shown in Table 1 can be obtained for the optimal design of the hydraulic cylinder;

Table 1: Data after optimization of erecting hydraulic cylinders

Through the above process, it can be obtained that the installation distance of the cylinder, the stroke _of the cylinder at 93°, the distance L3 from the rotation fulcrum O to the upper fulcrum O1 _of the vertical cylinder along the load direction, and the distance from the rotation fulcrum O to the lower fulcrum _O2 of the vertical cylinder. Based on the optimized data of the erecting hydraulic cylinder, such as the horizontal distance L ₁ , the hydraulic cylinder is designed.

Embodiment 3: The design process of the disturbance compensation-based leveling process control method described in Step 2 includes:

Focusing on the rapid leveling requirements of special vehicles under heavy load conditions, in view of the low leveling accuracy of traditional hydraulic leveling cylinders under heavy load conditions, electric cylinders are used as leveling legs to establish a deformation error model of electric cylinders and analyze them. The load characteristics of the outrigger cylinder under the four-point leveling condition, the deformation error generated by the outrigger deformation during the leveling process of the electric cylinder is used as the feedforward input of the feedback control, and the interference compensation feedback method is used to correct the leveling error. A rapid leveling control strategy for special vehicles based on interference compensation; the leveling system is co-simulated and verified by AMESim and MATLAB/Simulink software, and the experimental verification is carried out through the built experimental prototype:

Step201. Focusing on the rapid leveling requirements of special vehicles under heavy load conditions, in view of the low leveling accuracy of traditional hydraulic leveling cylinders under heavy load conditions, electric cylinders are used as leveling legs to establish an electric cylinder deformation error model

Step2011. Theoretical error calculation of leveling process

The error of the body leveling is mainly affected by the deformation of the outrigger and the frame. The main deformation in the electric cylinder of the leveling outrigger comes from the deformation of the planetary roller screw. The axial deformation of the component is mainly divided into the following three situations: One is the Hertzian deformation of the point contact thread groove between the thread and the roller, the other is the axial deformation of the lead screw and the nut when they are in contact with the roller, and the deformation of the thread when the lead screw and the nut are in contact with the roller respectively;

(1) Set in Figure 8, F ₀ is the axial force of the planetary roller screw, and the force of each contact point is the same, and the force of each contact point can be calculated; Figure 9 is the force of the contact point, F _n is the contact normal force, F _a is the axial force, F _t is the tangential force, F _r is the radial force, F _s is the resultant force of the axial force and the tangential force, λ is the lead angle of the roller, λ=4°; θ is the contact angle between screw and roller, nut and roller, θ=45°;

Then the relationship between the total axial force and the normal force of a single contact point is

where n is the number of rollers, which is 12;

(2) According to the Hertz theory, combined with the actual contact situation of the planetary roller screw structure in this embodiment, it is determined that the four main curvatures of the point contact between the center screw and the roller are:

In the formula, R is the arc radius at the contact point between the roller and the center screw, which is 31mm; R ₁ is the radius of the thread raceway of the center screw, which is 24mm; d ₁ is the radius from the contact point to the center screw, which is 24.2mm; d ₂ is the radius from the contact point to the roller axis, which is 6.3mm;

It can be seen that the curvature sum is:

∑ρ=ρ ₁₁ +ρ ₁₂ +ρ ₂₁ +ρ ₂₂

The principal curvature function is:

(3) According to the Hertzian contact theory, the elastic deformation of the contact surface is obtained as:

In the formula, E ₁ and E ₂ are the elastic modulus of the roller and the screw, both are 210MPa; μ ₁ and μ ₂ are the Poisson’s ratio of the roller and the screw, both are 0.3; F ₀ is the axial force;

可根据F(ρ)的值查表获得，为1.1；in the formula

It can be obtained by looking up the table according to the value of F(ρ), which is 1.1;

(4) Bring the above parameters into formula (13) to get:

There is a relationship between the axial deformation of the planetary roller screw and the Hertzian contact deformation as shown in equation (15)

It can be seen from equation (15) that the elastic deformation of the outrigger is related to the force, so it is necessary to analyze the force of the special vehicle;

The influence of frame deformation is the measurement error of the inclination sensor. In order to eliminate this error, the roll angle is used as the main basis for leveling in combination with the actual use of on-board equipment, and the inclination sensor is installed on the rear beam to greatly reduce the inclination angle. Measurement error.

Step2012. Theoretical calculation of bearing capacity of leveling outriggers

(1) Take the frame and the whole load as the force object for analysis, and each outrigger is rigidly connected to the frame; when the initial state is leveled, the outrigger has an axial support force on the frame and two mutually perpendicular The radial support force acts; the force of the special vehicle in the pitching state and the special vehicle in the rolling state is shown in Figure 10, and the axial force and radial force of the two front outriggers on the frame are respectively f _1y , f _1x , f _1z ; the axial force and radial force of the two rear outriggers on the frame are respectively f _2y , f _2x , f _2z ; the body pitch angle α, the body roll angle β;

In Figure 10: the left and right span of the two front outriggers is h=3m, and the span of the two rear outriggers is the same; the span of the front and rear outriggers on the same side is l=12m, the frame mass m1 ₌ 28t, the load mass _m2 =35t; the total mass m=63t; the center of mass of the frame is located in the vertical symmetry plane of the car body, and the horizontal distance l ₁ =8.1m from the central axis of the rear legs; the center of mass of the load is located in the vertical symmetry plane of the car body, and the horizontal distance l from the central axis of the rear legs ₂ = 6.2m; gravitational acceleration g = 9.8m/s ² ; the left and right spans of special vehicles are relatively small, and the force of the left and right electric cylinders is considered as the same force;

(2) Taking the frame plane as the benchmark, tracking the balance between the frame gravity and the axial force of the outriggers when the state of the body changes, the balance equation can be listed; the resultant force in the axial direction of the outriggers is equal to the frame and the load gravity in the support The projection on the axial direction of the legs; when the vehicle body has both a pitch angle and a roll angle, the force balance equation is as follows:

f _1y +f _2y = mg cosαcosβ (29)

f _1x +f _2x = mg sinα (30)

f _1z +f _2z = mg sinβ (31)

Taking the connecting line of the two front legs as the rotation axis, the moment balance analysis is carried out. The moment balance equation is as follows:

[m ₁ g(ll ₁ )+m ₂ g(ll ₂ )]cosαcosβ=f _2y l (32)

Taking the connecting line of the two rear outriggers as the rotation axis, the moment balance analysis is carried out. The moment balance equation is as follows:

[m ₁ gl ₁ +m ₂ gl ₂ ]cosαcosβ=f _1y l (33);

Step202. Propose a leveling control strategy based on disturbance compensation, calculate the deformation variable of the electric cylinder through theory, use it as the initial input error of the leveling controller, use the shape variable as the feedforward of the control system, and use the fuzzy PID control method for feedback control. The two are fused together to quickly level;

Step2021. The algorithm structure of adaptive fuzzy PID control based on interference compensation is shown in Figure 11. First, according to formula (26), the initial error is calculated as feedforward compensation, and the feedback control adopts traditional adaptive fuzzy PID control. The input error of the fuzzy controller e is obtained according to the interference compensation value of the feedforward, and then the error rate of change e _c is calculated;

Step2022. The fuzzy controller adjusts the values of ΔK _p , ΔK _I and ΔK _D by continuously updating _e and ec during operation, so as to realize the online self-tuning of PID parameters, and meet the different requirements of different _e and ec for control parameters, so as to achieve control purposes;

Among them, the fuzzy universes of the input and output linguistic variables e, e _c , ΔK _p , ΔK _I , and ΔK _D of the fuzzy controller are all [-6, 6], and the fuzzy subsets are [NB, NM, NS, ZO, PS, PM, PB], considering the coverage and sensitivity, stability and robustness of the universe, each fuzzy subset adopts a Gaussian membership function;

The control rules of ΔK _p are shown in Table 2, the control rules of ΔK _I are shown in Table 3, and the control rules of ΔK _D are shown in Table 4;

Table 2: ΔK _p control rule table

Table 3: ΔK _I Control Rule Table

Table 4: ΔK _D control rule table

Step203. Carry out leveling system modeling and control analysis

Step2031. Construction of simulation model of leveling system

(1) Equivalent modeling of the electric cylinder in AMESim. The main transmission structure of the electric cylinder is a planetary roller screw, which can convert rotary motion into linear motion. Its working principle is similar to the threaded nut structure. It is simplified into a threaded nut structure, and the difference can be eliminated by setting its parameters according to its three-dimensional structure. This simplification has no effect on the simulation accuracy; the leveling legs are shown in Figure 12;

(2) Since the special vehicle uses four fulcrums for leveling, a mechanical model of four leveling legs is established. Since the special vehicle calculates the corresponding displacement of the legs from the collected inclination signal during actual operation, the special vehicle simulation The control signal of the model directly adopts the outrigger displacement signal, and the co-simulation icon with MATLAB/Simulink is created in AMESim. The co-simulation module is shown in Figure 13;

(3) Combined with the leveling leg structure and control system, the overall model of the leveling system is shown in Figure 14. The calculated theoretical force signal 2 of the planetary roller screw is used to calculate the output compensation value through function 3. When the leveling leg touches The ground time is combined with the expected displacement signal 5 and compared with the actual displacement signal 4 as the input of the controller, and the input signal of the drive motor is obtained by processing, thereby controlling the speed and displacement of the outrigger;

Step2032. Refer to Figure 12 and Table 2-4 to build a system block diagram in Simulink, and use the trial and error method to determine the initial parameters of the PID controller. The initial values of ΔK _p , ΔK _I and ΔK _D are 1500, 30, and 5, respectively. In the fuzzy universe, the scale factors of the error and the error rate of change are 150 and 0.2, and the quantization factors of ΔK _p , ΔK _I and ΔK _D are 300, 5, and 1; the simulation model of the adaptive fuzzy PID controller is built as shown in Figure 15 Show;

The co-simulation model in the MATLAB/Simulink environment is shown in Figure 16;

Step2033. According to the above-mentioned leveling method, combined with the leveling process in Fig. 4, the leveling process in the simulation is simplified into the following three stages: the first stage is the no-load high-speed ground contact stage of the electric cylinder; the second stage is each leveling process The outrigger touches the ground detection; the third stage is the low-speed lift and leveling;

When the leveling mechanism is in the third stage of low-speed lift and leveling, in order to ensure that the special vehicle leaves the ground, the leveling outrigger needs to be raised by another 5mm after it touches the ground;

The following two working conditions are analyzed: the first is leveling under the condition of large inclination angle, that is, the working condition with the pitch angle of 1.9° and the roll angle of 2.94°; the second is the leveling under the condition of small inclination angle, that is, the pitch angle The working condition where the angle is 0.28° and the roll angle is 0.06°;

Under the condition of large inclination angle, the left rear outrigger is set as the highest point in the third stage, the displacement is e ₂ =5mm, the displacement of the right front outrigger is e ₄ =245mm, the displacement of the right rear outrigger is e ₃ =159mm, The displacement of the left front outrigger is e ₁ =90mm;

When the leveling enters the second stage, the compensation signal of the input force is calculated by formulas (3.6)-(3.10). According to the average force of the two legs, the input force of the front outrigger is 180712N, and the input force of the rear outrigger is 127155N.

Set the simulation time to 10s, run the simulation in the MATLAB/Simulink environment, and observe the displacement of each leg in AMESim, as shown in Figure 17(a).

Set the leveling pitch angle to 0.28° and the roll angle to 0.06°. In the third stage, the left rear outrigger is the highest point, the displacement is e ₂ =5mm, the displacement of the right front outrigger is e ₄ =66mm, and the right The displacement of the rear outrigger is e ₃ =7mm, and the displacement of the left front outrigger is e ₁ =64mm.

Input the displacement signal of each outrigger in the signal module, in order to fit the actual experiment as much as possible, 0-0.81s is for the detection of the leveling system operation, the displacement of each outrigger is 0, and each outrigger remains motionless in the stage of 9.28-10s, and the first The displacements of the legs from the first stage to the third stage are as follows.

When the leveling enters the second stage, the compensation signal of the input force is calculated according to the set value and equations (29)-(33). The input force of the front outrigger is 181216N, and the input force of the rear outrigger is 127480N;

Set the simulation time to 6s, run the simulation in the MATLAB/Simulink environment, and observe the displacement of each leg in AMESim, as shown in Figure (17)b;

It can be seen that the leveling outriggers in each stage will produce large errors after they are extended in place, but they will be stable in a short period of time, and can be quickly extended in place according to the predetermined signal. From the simulation results, it can be concluded that the interference compensation-based The adaptive fuzzy PID control method can quickly level the special vehicle, and the leveling error is small;

Step204. Carry out the experimental verification of the electric drive leveling system

Step2041. Build a leveling system

Build leveling legs, as shown in Figure 18 after connection;

(1) The quick leveling system is mainly composed of a leveling control unit, a leveling drive unit and a leveling execution unit. The leveling control unit uses an industrial computer + motion control board to control the servo motor, including the leveling control unit. Electrical circuit, leveling controller (IPC), leveling control panel (touch screen), two-axis inclination sensor, upper and lower limit switches of each outrigger; leveling drive unit includes main motor servo driver, auxiliary motor servo driver and Brake; the leveling execution unit is the electric cylinder of each outrigger (including the speed control reducer), and the system block diagram is shown in Figure 19:

(2) The schematic diagram of the leveling control system is shown in Figure 20; the controller sends data to the servo motor drivers (including the main motor) of the four leveling electric cylinders through the bus according to the received remote control instructions or local panel operation instructions Servo driver and auxiliary motor servo driver); communication between the servo motor driver and the servo motor, sending commands such as rotation speed, rotation angle, rotation acceleration and modulating the drive current to the servo motor; a multi-turn absolute encoder is installed at the tail of the motor as the position Feedback device, multi-turn absolute encoder directly measures the number of rotations of the motor, the servo motor is decelerated through the planetary reducer and gear pair, and at the same time amplifies the torque to drive the ball screw to rotate; the ball screw pair nut and the push rod are in the guide key. Reciprocating linear motion is performed under the constraint to realize the telescopic motion of the electric cylinder; when the four electric cylinders all touch the ground, the leveling controller calculates the length and speed of each cylinder to extend in real time according to the vehicle inclination data detected by the inclination sensor, and gives them respectively. Each cylinder sends different speed and position commands to realize the leveling control of the car body; after the car body is leveled in place, the car body is checked for the leveling accuracy and the outrigger pressure is compensated to complete the rapid car show and leveling work;

The system adopts a four-point leveling scheme, and the leveling system consists of a detection device, an actuator and a control system; among them, the detection device is a dual-axis inclination sensor, which is used to detect the pitch angle and yaw angle of the vehicle body; The size is a sign that the system judges whether the car body is level. The accuracy of the sensor in the full temperature section directly determines the leveling accuracy of the leveling system; the actuator is composed of four sets of electric outriggers, and the outriggers are composed of ball screw pair, reducer, Servo motor and its drive system are composed; the control system is composed of industrial computer + motion control board, the controller receives the body inclination measured by the inclination sensor, and after calculating the lifting distance of each outrigger, the motion control board performs interpolation calculation, And through the EtherCAT bus, the control command is sent to the driver of each outrigger motor, and the driver then drives the servo motor to drive the outrigger to complete the specified lifting action;

Step2042. Leveling control verification under large/small inclination conditions

The experiment is carried out under the condition of large inclination angle. The initial pitch angle corresponding to this condition is 1.9° and the roll angle is 2.94°. The experimental data is processed to obtain the change curve of inclination angle and displacement during the experiment, as shown in Figure 21(a ), as shown in Figure 21(b), the experiment was carried out under the condition of small inclination angle. The corresponding initial pitch angle of this condition was 0.28°, and the roll angle was 0.07°. After processing the experimental data, it was obtained that the inclination angle and the The change curve of displacement is shown in Figure 21(c) and Figure 21(d);

Step2043. Comparative analysis

The experimental data under the two working conditions are compared with the simulation data, as shown in Figure 22. It can be seen from Figure 21 that the traditional fuzzy PID control special vehicle is leveled in 5.98s, the pitch angle leveling accuracy is 0.05°, and the roll is 0.05°. The angular leveling accuracy is 0.02°;

From Figure 23(a), it can be seen from 0-4.5s that the error in the no-load rapid extension stage of the leveling outrigger is relatively large, and the maximum deviation is 14.98mm; in 4.5s-9.28s, the leveling outrigger touches the ground to adjust The error in the flat stage is small, the maximum error is 1.3mm, and the average error of each leg does not exceed 0.5mm;

It can be seen from Figure 23(b) that at 0-2.2s, the error in the no-load rapid extension stage of the leveling outrigger is relatively large, and the maximum displacement error of the leveling outrigger is 20mm. The error in the leveling stage of the leg touching the ground is small, the maximum error is 1mm, and the average error of each leg does not exceed 0.5mm;

It can be seen from the above simulation process that the coordinated leveling method for special vehicles based on interference compensation described in this embodiment has completed the rapid leveling experiment of special vehicles. Leveling, the pitch angle leveling accuracy reaches 0.05°, and the roll angle leveling accuracy reaches 0.001°; the special vehicle is leveled in 5.42s in the state of small inclination angle, the pitch angle leveling accuracy is 0.04°, and the roll angle leveling accuracy is 0.04°. Compared with the traditional fuzzy PID control, the fuzzy PID control based on interference compensation reduces the leveling time by 9.3%, the pitch angle leveling accuracy is increased by 20%, and the roll angle leveling accuracy is improved 90%. Experiments show that the control method based on disturbance compensation has high leveling accuracy, which verifies the feasibility of the rapid leveling method for special vehicles.

Embodiment 4: The design process of the high-voltage energy storage-based coordinated erection method for special vehicles described in Step 3 includes:

Step301. Establish mathematical model of rapid erection system

Step3011. Establish mathematical model of high pressure accumulator

(1) In order to determine the hydraulic oil pressure output by the high-pressure accumulator, first analyze the pressure change of the air cavity in the accumulator, the change process of the gas is an adiabatic process, and the thermodynamic equation of the air cavity is:

p _g V _g = _mg RT _g (34)

In the formula, p _g is the air cavity pressure; V _g is the air cavity volume; m _g is the gas mass in the air cavity; R is the gas constant; T _g is the gas temperature in the air cavity;

(2) It can be concluded that the gas pressure change equation is:

Then analyze the force of the accumulator liquid cavity, the force equation of the liquid cavity can be obtained as:

In the formula, p _o is the accumulator fluid chamber pressure; A _p is the accumulator piston area; V _o is the fluid chamber volume; m _o is the fluid chamber fluid mass and piston mass; C _o is the oil viscous damping coefficient;

(3) Finally, the outlet flow of the high-pressure accumulator is analyzed, and the hydraulic oil pressure equation in the accumulator is:

In the formula, E is the elastic modulus of the oil; q is the output oil flow of the accumulator;

In formula (37), the output oil flow equation of the accumulator is:

为临界雷诺数；In the formula, C _q is the flow coefficient; C _qmax is the maximum flow coefficient; A _o is the valve port area of the liquid throttle valve; _{ph is the pressure in the hydraulic cylinder; ρ o is} the oil density; _Re is the Reynolds number;

is the critical Reynolds number;

Step3012. On the basis of the high-pressure accumulator, establish the mathematical model of the three-stage hydraulic cylinder

Taking the three-stage hydraulic cylinder as the research object, the outer cylinder is the first-stage hydraulic cylinder, the middle cylinder is the second-stage hydraulic cylinder, and the piston, piston rod, and inner cylinder constitute the third-stage hydraulic cylinder. The cavity is filled with oil, the pressure rises, the first-stage cylinder overcomes the external force and starts to move. When the movement reaches the end of the stroke, the first-stage cylinder collides with the second-stage cylinder, which drives the second-stage cylinder to start moving. Similarly, the second-stage cylinder starts to move. After the cylinder is in place, the third-stage cylinder is driven to move. Since the area of the cylinder barrel decreases in turn, the pressure of the hydraulic cylinders extended in sequence will have a sudden change during the stage change, which will cause shock;

(1) The positive and negative cavities of the hydraulic cylinder are regarded as a node cavity respectively, and the pressure equation of the two cavities is established by the node cavity method, and the output force of the cylinders at all levels can be calculated, and the mathematical model of the three-stage cylinder can be obtained as follows:

In the formula, E is the effective bulk elastic modulus of the oil; V _f and V _b are the initial volumes of the forward and reverse chambers of the multi-stage cylinder, respectively; Q _f and Q _b are the flow rates flowing into or out of the forward and reverse chambers, respectively; A _f3 , A _f2 , and A _f1 are the action areas of the _3rd , _2nd , and 1st-stage cylinder positive cavity respectively; _Ab3 , Ab2 , and Ab1 are the 3rd, 2nd, and 1st stage counter-cavity action areas respectively; l _3max , l _2max , l _1max is the maximum displacement of the 3rd, 2nd and 1st stage cylinders respectively; p _f and _pb are the pressures of the forward and reverse chambers of the oil cylinder respectively; x ₃₂ and v ₃₂ are the axial displacement and velocity of the 3rd stage cylinder relative to the 2nd stage cylinder respectively ; x ₂₁ , v ₂₁ are the axial displacement and velocity of the 2-stage cylinder relative to the 1-stage cylinder respectively; x _1p , v _1p are the axial displacement and velocity of the 1-stage cylinder relative to the piston rod; F ₃ , F ₂ , F ₁ is the output force of the 3rd, 2nd and 1st stage cylinders respectively; F _f3 , F _f2 , F _f1 are the frictional forces of the 3rd, 2nd and 1st stage cylinders during the operation respectively; F _p3 , F _p2 , F _p1 are 3, 2. The collision force between the first-stage cylinder and the piston rod;

(2) In equation (40), the friction model in the operation of the cylinder barrel adopts the improved LuGre model, and the mathematical model is as follows

where z is the average elastic deformation of the bristles; v is the relative velocity of the contact surface; σ _z is the stiffness coefficient; τ _z is the damping coefficient; η _z is the viscosity coefficient; v _s is the Stribeck velocity constant; F _c is the Coulomb Friction force; F _s is static friction force; h is oil film thickness;

(3) The hydraulic cylinder inter-stage collision model in Eq. (40) is based on the Hertzian contact force model, and its mathematical model is as follows

where K _p and K _n are the equivalent spring stiffness; μ is the hysteresis factor; δ is the normal penetration depth of the contact point; v _R and _vc are the speeds of the two cylinders; x is the relative displacement between the cylinders; g _p is the upper bound of cylinder displacement; g _n is the lower bound of cylinder displacement;

Step3013. Buffer device model and principle

In order to reduce the impact of hydraulic cylinder change, it is necessary to design a buffer device at the end of the stroke of each stage of the cylinder. With rod cavity and rodless cavity, the throttling area is constantly changed, so that during the erection process, when the first-stage cylinder is about to extend to the end of the stroke, the second-stage cylinder starts to act, making the hydraulic cylinder transition between stages The point transition is transformed into an interval transition to achieve the purpose of eliminating the transition shock.

The mathematical model of the flow q _s through the buffer orifice is shown in Equation 43:

In the formula, As is the flow area of the small hole, and _Δp is the pressure difference before and after the small hole;

In order to reduce the impact of the hydraulic cylinder when it is erected in place, the three-stage cylinder is designed with inner and outer guide sleeves to control the direction of movement, and by designing a certain taper, multi-stage buffers are used to reduce the impact of the erection in place.

Step302. Experimental verification

Step3021. Build the experimental prototype of the erection system

In order to meet the technical requirements and safety requirements for rapid erection of large loads, the rapid erection system of the experimental prototype adopts the technical scheme of hydraulic pump control + high-pressure energy storage device dual power sources, which can realize dual systems of pump control oil source and energy storage device oil source system control erection;

(1) Firstly, the structure of the accumulator is modeled. The high-pressure energy storage device adopts the piston type structure, which avoids the problem of intermolecular leakage in the long-term pressure holding of the bladder-type accumulator. One pre-charge can guarantee 10 The air cavity has zero leakage for more than one year; in order to meet the requirements of fast erection load and speed conditions, the design shape is φ406×4213, and the weight is 1330kg; low temperature NBR seal, temperature range: -50℃～+110℃, dynamic sealing speed v= 2m/s;

(2) Next, model the vertical hydraulic cylinder. The vertical hydraulic cylinder is a three-stage cylinder and adopts a double-acting form. Its shape is shown in Figure 25. The first stage and the second stage adopt a differential connection method. It can be retracted, and the third stage is designed with an oil return cavity to adapt to the pulling load conditions of the erection end;

Both the initial and final sections of the cylinder are designed with a new type of end-faced buffer damping device. Through damping matching, the buffering of erection and levelling in place and the precise control of the erection angle are realized; The damping hole is designed in the cylinder barrel of the first stage; during the extension process, when the first cylinder extends for a certain length but has not reached the end of the stroke, the second cylinder starts to act, so that the point transition during the transition between the cylinder stages becomes an interval transition, Effectively eliminate the impact during the transition between the primary/secondary cylinders; for the same reason, the same technology can also be used between the secondary and tertiary cylinders to eliminate the impact during the transition between stages; As shown in Figure 26; the oil cylinder seal adopts the combination of step seal and pan plug seal to achieve zero leakage of hydraulic oil and maintenance-free life cycle of the oil cylinder;

(3) Finally, the erection hydraulic system is built according to the hydraulic principle of the simulation model, including variable pump oil source device, high-pressure energy storage device, valve control system, three-stage hydraulic cylinder, etc. The power of the erection device adopts 90kW motor Drive, considering the requirement of straightening accuracy, the oil pump adopts an electric proportional plunger pump with a displacement of 180, which can realize the speed control of the normal extension and retraction of the erection device; the hydraulic valve adopts a zero-leakage cartridge valve with manual override function to ensure The pressure effect is good and the flow capacity is strong; the physical diagram of the cartridge valve group is shown in Figure 27;

The erection control system consists of a controller, a monitoring recorder, a control button, a pressure sensor, an erection pole inclination sensor and a proximity switch; the erection control principle is shown in Figure 28;

In order to avoid misoperation, during the development process, a start button is set on the control panel. Only after pressing the start button on the control panel and the indicator light is on, the erection and leveling actions of the erection device can be performed; The vertical and leveling action buttons are arranged with monitoring recorder, emergency stop switch and indicator light; the control panel is shown in Figure 29; the monitoring recorder monitors the vertical angle, in-position signal, hydraulic system pressure value, and the operation status of each IO of the controller in real time. And the system fault code; the controller controls the oil pump motor through the CAN bus to realize the speed regulation and start-stop control of the oil pump motor;

The erection command is divided into two categories: normal erection and quick erection. The priority of quick erection is the highest, and the priority of normal erection is the lowest; when any of these two erection buttons are pressed, the controller controls the corresponding solenoid valve to perform corresponding actions; The erecting device is equipped with an inclination sensor, and two proximity switches are set at the position of erecting in place; when erecting, the inclination angle of the erecting device relative to the horizontal ground is obtained by integrating the values collected by the erecting device inclination sensor and the inclination sensor of the chassis leveling device , in the inclination angle of the integrated erection device relative to the ground and the proximity switch value of the erection position to judge the erection position, close the erection solenoid valve, and the erection action stops;

When any leveling action is pressed, the controller controls the leveling action solenoid valve to execute the leveling action. Among them, the priority of emergency leveling is higher than the normal leveling action; two in-position proximity switches are set at the leveling in-position position; comprehensive The tilt angle of the vertical cylinder relative to the ground and the in-position proximity switch signal determine whether the leveling is in place; the experimental prototype of the special vehicle is shown in Figure 30;

Step3022. Analysis of experimental results of rapid erection system

Charge the accumulator before the rapid erection experiment, manually stop charging when the pressure reaches 33Mpa, conduct the rapid erection experiment, record the change curve of the erection angle from 0° to 95°, and intercept the simulation result for 65s- The curve between 85s, the erected state of the experimental prototype is shown in Figure 31, and the experimental results and simulation comparison results are shown in Figure 32;

According to the analysis of the experimental results, at 6.81s, the multi-stage cylinder changed a large impact, and the experimental prototype produced obvious vibration. The maximum vertical vibration amplitude was 4.7°; at 12.5s, the vertical angle reached 95.3°, The maximum swing angle is 3.3°; the vibration amplitude is reduced to 0.9° at 14.5s, and the erection angle is stable to 95°;

It can be seen from Figure 32 that the deviation between the simulation and experimental results is within 0.5°, except for the two time periods of changing the stage and erecting in place, and the experiment verifies the simulation results well.

Embodiment 5: The determination of the influence relationship between the variable load impact and the rapid vehicle display system of the special vehicle during the coordinated motion process described in Step 4 is completed by relying on the coordinated motion co-simulation process;

Step401. Collaborative motion co-simulation

Step4011. Construction of co-simulation model for special vehicles

(1) In the AMESim simulation model, the erecting part can output the horizontal and vertical forces of the lower hinge point of the erecting hydraulic cylinder, as well as the horizontal and vertical forces of the connecting part between the load and the vehicle chassis. The vertical force acting on the vehicle chassis is subjected to force analysis, as shown in Figure 33;

According to the special vehicle parameters, according to the force balance and moment balance, formulas (44)-(45) are obtained:

为单个前支腿所受支反力，

单个后支腿所受支反力，L₁为起竖液压缸下铰支点距离后侧支腿的距离，为3.243m，l为特种车辆前后支腿距离，为12m；In the formula, F _gy is the vertical force of the erecting hydraulic cylinder on the chassis of the special vehicle,

is the reaction force of a single front outrigger,

The reaction force of a single rear outrigger, L ₁ is the distance between the lower hinge fulcrum of the vertical hydraulic cylinder and the rear outrigger, which is 3.243m, and l is the distance between the front and rear outriggers of special vehicles, which is 12m;

Equations (46) and (47) can be obtained

(2) Analyze the force in the vertical direction at the connection between the load and the chassis of the special vehicle, as shown in Figure 34. It can be seen from Figure 34 that the vertical force at point O is concentrated on the rear outrigger;

According to the analysis of the mechanical relationship between the erection system and the leveling system of the special vehicle, the force in the Y direction output by the erection mechanism is used as a part of the input signal of the leveling control system; after the leveling and erection models are connected, a joint simulation is obtained. The model is shown in Figure 35;

Step4012. Collaborative motion simulation analysis

According to the analysis, the specific parameters in the simulation model in Figure 36 are set as follows. In function component 6, input the vertical force of the vertical hydraulic cylinder on the front outrigger, and in component 7, input the vertical force of the vertical hydraulic cylinder on the rear outrigger. Force, the vertical direction force at the connection between the load and the chassis of the special vehicle is input in component 8, and the input signal 9 is shown in Figure 37. It is 0 from 0 to 65s. At this time, it is the charging stage of the erection accumulator, and erection is not performed. Work, in 65s-75s, the input is 1, the leveling system is working at this time, 75s-120s, the leveling is over, the input is 0;

The coordinated motion system is simulated under two working conditions and the following two working conditions are analyzed: the first is the working condition with large inclination angle, that is, the working condition with the pitch angle of 1.9° and the roll angle of 2.94°; It is the working condition of small inclination angle, that is, the working condition where the pitch angle is 0.28° and the roll angle is 0.06°;

The simulation process of cooperative motion is as follows:

In 0-65s, the accumulator of the erection system is charged, and the leveling outrigger does not move; in 65s-68.69s, the leveling outrigger extends and touches the ground, and starts the rapid erection process; in 68.69s-75s, the adjustment The leveling outrigger touches the ground for leveling; in 73.47s-120s, the leveling outrigger does not move until the whole process of rapid erection is completed;

The leveling data in the time period of 65s-75s in the simulation results is selected, and the data is analyzed. The simulation results of the displacement of the leveling outrigger under the condition of large inclination angle are shown in Figure 38(a), and it is lowered under the condition of small inclination angle. The displacement of the flat outrigger is shown in Figure 38(b);

From the simulation results, the coordinated motion can complete the leveling process within 10s; then the erection process is analyzed, the displacement of the erection hydraulic cylinder is shown in Figure 39, and the erection angle is shown in Figure 40;

Step402. Analyze according to the simulation results. It can be seen from Figure 38 that the leveling motion is greatly affected, and the coordinated motion mainly affects two aspects: one is the accuracy of the leveling system, and the other is the change of the radial force and load of the leveling electric cylinder;

Firstly, the accuracy of the leveling system is analyzed, and the simulation results of the leveling process during serial motion and the leveling results during coordinated motion are compared and analyzed, and the comparison chart of displacement deviation under two working conditions is obtained. The simulated displacement deviation of the legs is shown in Fig. 41(a), and the simulated displacement deviation of the leveling legs under the condition of small inclination angle is shown in Fig. 41(b);

It can be seen from the figure that the deviation of the leveling outriggers keeps increasing after they touch the ground. The maximum error can reach 4.77mm under the condition of large inclination angle, and the maximum error can reach 4.75mm under the condition of small inclination angle. The process is compared, and it is found that the time period when the leveling error suddenly changes is the level change of the second and third vertical hydraulic cylinders. During the level change, the errors of each outrigger show different trends. The deviation value of the left and right front outriggers decreases suddenly, and the left and right back The deviation value of the outrigger increases suddenly; but after the change is completed, the error will return to the trend before the change.

Combined with the vertical force curve shown in Figure 42 and the axial force change curve of the front outrigger and rear outrigger shown in Figures 43 and 44, the deviation curve trend of the leveling outrigger and the change curve of the axial force received are analyzed. The trend is roughly the same. For the time period of sudden change of force, compared with the erection force, it can be seen that the erection force changes from push force to pull force when the second and third stage hydraulic cylinders are changed, resulting in the reduction of the force on the outriggers before leveling. After leveling, the force on the outrigger increases, so the leveling deviation changes abruptly;

The radial force of the leveling legs is analyzed. Because the radial force is relatively large under the condition of large inclination angle, the change of radial force during the erection process under the condition of large inclination angle is analyzed. The change of radial force is shown in Figure 45. Show;

It can be seen from Figure 45 that the maximum combined force of the four leveling legs is less than 150kN, but each leg meets the requirement that the radial force is less than 14.7kN;

To sum up, combined with Equation (25), the roll angle leveling accuracy is 0.004° under the condition of large inclination angle, the pitch angle accuracy is 0.053°, and the final roll angle leveling accuracy under the condition of small inclination angle is 0.0025 °, the pitch angle accuracy is 0.043°, it can be seen from the results that the coordinated motion reduces the roll angle leveling accuracy by at most 0.003°, and the pitch angle leveling accuracy by at most 0.003°; the radial force of the leveling legs meets the design requirements;

Step403. Influence of coordinated motion on erection process

The effect of the coordinated motion of special vehicles on the erection process is mainly whether the load will be overloaded. Therefore, the acceleration of the erection center of gravity needs to be checked. Figure 46(a) shows the acceleration comparison in the horizontal direction, and Figure 46(b) shows The acceleration comparison in the vertical direction;

It can be seen from Figure 46 that the acceleration of the center of gravity during the coordinated exhibition vehicle movement is greater than the acceleration during the serial operation. The acceleration in the vertical direction is the largest at the beginning of the erection, and the maximum acceleration in the vertical direction of the coordinated movement can reach 8.04. The acceleration in the vertical direction is 6.02; the acceleration in the horizontal direction reaches the maximum when the second and third levels are changed, the maximum acceleration in the horizontal direction of the coordinated movement can reach 5.56, and the acceleration in the horizontal direction of the serial movement is 4.21; but it is still less than 1g, which meets the design requirements.

The foregoing has shown and described the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above-mentioned embodiments, and the descriptions in the above-mentioned embodiments and the description are only to illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have Various changes and modifications fall within the scope of the claimed invention. The claimed scope of the present invention is defined by the appended claims and their equivalents.

Claims (9)

1. A special vehicle rapid vehicle display cooperative control method is characterized in that: comprises the steps of

Step1, in the process of the special vehicle collaborative exhibition, providing various boundary conditions of the special vehicle collaborative exhibition movement, planning a scheme of the special vehicle collaborative movement in the process of the special vehicle exhibition according to the boundary conditions, and simultaneously providing a collaborative exhibition mode of parallel work;

step2, designing a special vehicle cooperative leveling method based on interference compensation, and controlling a cooperative vehicle spreading process of the special vehicle by using the special vehicle cooperative leveling method based on interference compensation;

and Step3, designing a special vehicle collaborative erection method based on high-pressure energy storage, and controlling a collaborative vehicle exhibition process of the special vehicle by utilizing the special vehicle collaborative erection method based on the high-pressure energy storage to complete rapid vehicle exhibition collaborative control of the special vehicle.

2. The special vehicle rapid exhibition cooperative control method according to claim 1, wherein: the design process of the cooperative motion scheme described in Step1 includes

Step101, determining a cooperative vehicle-displaying scheme that a leveling system and a vertical system work simultaneously according to boundary conditions in the cooperative vehicle-displaying process of the special vehicle;

step102, analyzing a leveling principle of four-pivot leveling on the basis of a special vehicle collaborative vehicle-spreading scheme, and leveling the vehicle by adopting a three-point height-by-height method;

and Step103, optimizing the erecting mechanism and designing a quick erecting system scheme on the basis of the special vehicle collaborative vehicle exhibition scheme.

3. The special vehicle rapid exhibition cooperative control method according to claim 2, characterized in that: the analysis process of the four-pivot leveling in the Step102 comprises

(1) Leveling of the system can be simplified into leveling of a certain platform plane, and a double-shaft tilt angle sensor is arranged in X, Y two mutually vertical directions of the platform to measure horizontal tilt angles in the two directions;

(2) set the supporting leg i in the horizontal coordinate system OX ₀ Y ₀ Z ₀ The coordinates in are ⁰ P _i ＝( ⁰ P _iX , ⁰ P _iY , ⁰ P _iZ ) ^T In the platform coordinate system OX ₁ Y ₁ Z ₁ The coordinates in are ¹ P _i ＝( ¹ P _iX , ¹ P _iY , ¹ P _iZ ) ^T (ii) a Meanwhile, assuming that initial angles alpha and beta of the platform are not 0, the platform is a small inclination angle, and the conditions that alpha and beta are small angles are met, the transformation matrix between the two coordinate systems is obtained as follows:

(3) set in a coordinate system OX ₁ Y ₁ Z ₁ In, the coordinates of each leg are: ¹ P _i ＝( ¹ X _i , ¹ Y _i , ¹ Z _i ) ^T (ii) a Then

The coordinates of each fulcrum Z are:

⁰ Z _i ＝(-α,β,1)( ¹ X _i , ¹ Y _i , ¹ Z _i ) ^T

(4) and (3) pre-supporting before leveling, firstly judging the highest point, and taking the point as the origin of coordinates, wherein the initial position of each supporting leg is as follows:

⁰ Z _i ＝-α ¹ X _i +β ¹ Y _i + ¹ Z _i

it is clear that, ¹ Z _i 0, the above formula can therefore be represented as:

⁰ Z _i ＝-α ¹ X _i +β ¹ Y _i

(5) setting i as h as the highest point, ⁰ Z _h ≥ ⁰ Z _i and at any moment, the position difference between each fulcrum and the highest point is as follows:

e _i ＝ ⁰ Z _h - ⁰ Z _i ＝-α( ¹ X _h - ¹ X _i )+β( ¹ Y _h - ¹ Y _i )

(6) all the supporting legs are symmetrically distributed along the front, the back and the left and the right of the frame, and the distance between the long sides of the distributed supporting legs is L _a Short side interval of L _b Then, the coordinates of each leg in the moving coordinate system are:

accordingly, the extension amount of each supporting leg is calculated, the positive and negative of the inclination angle obey the right-hand rule, the supporting leg with the highest corresponding coordinate is different according to different combinations of the positive and negative of the two inclination angles in the X-axis direction and the Y-axis direction, and the four conditions are analyzed as follows:

(1) when α < 0, β > 0, leg 1 is highest:

(2) when alpha is more than 0 and beta is more than 0, the supporting leg 2 is the highest,

(3) when alpha is less than 0 and beta is more than 0, the supporting leg 3 is the highest,

(4) when alpha is less than 0 and beta is more than 0, the supporting leg 4 is the highest,

from the four cases above, it can be seen that: when the landing legs are adjusted every time, the adjustment quantity of each landing leg is 0, | alpha L _a ||，||βL _b ||，||αL _a ||+||βL _b One of the four numerical values of | l is distributed according to different high points; the leveling process can be iterated circularly until the levelness reaches the requirement.

4. The special vehicle rapid exhibition cooperative control method according to claim 1, characterized in that: the design process of the special vehicle collaborative leveling method based on the disturbance compensation in Step2 comprises

Step201, taking an electric cylinder as a leveling supporting leg, and establishing an electric cylinder deformation error model by calculating a theoretical error of a leveling process and calculating a theoretical bearing capacity of the leveling supporting leg;

and Step202, introducing a leveling control strategy based on interference compensation into the deformation error model of the electric cylinder, taking the deformation quantity of the electric cylinder as an initial input error of a leveling controller, taking the deformation quantity as a feedforward of a control system, and performing feedback control by adopting a fuzzy PID control method to obtain the special vehicle cooperative leveling method based on the interference compensation.

5. The special vehicle rapid exhibition cooperative control method according to claim 4, wherein: the leveling process theoretical error calculation process in Step201 comprises

(1) In the planetary roller screw, F is provided ₀ For axial stressing of the planetary roller screw, with the same stressing at each contact point, F _n To contact normal force, F _a As axial force, F _t As tangential force, F _r As radial force, F _s The resultant force of the axial force and the tangential force is adopted, and lambda is the lead angle of the roller; theta is a contact angle between the screw rod and the roller and between the nut and the roller;

the total axial force is related to the normal force of the single contact point by

In the formula, n is the number of the rollers;

(2) according to the Hertz theory, four main curvatures of point contact between the central screw and the roller are respectively determined as follows:

in the formula, R is the arc radius of the contact point of the roller and the central screw; r is ₁ The radius of the thread roller path of the central screw rod; d is a radical of ₁ The radius from the contact point to the central lead screw; d ₂ The radius of the contact point to the roller axis;

as can be seen, the curvature sum is:

Σρ＝ρ ₁₁ +ρ ₁₂ +ρ ₂₁ +ρ ₂₂

the principal curvature function is:

(3) according to the Hertz contact theory, the elastic deformation of the contact surface is obtained as follows:

in the formula, E ₁ And E ₂ The elastic modulus of the roller and the screw rod; mu.s ₁ And mu ₂ Is the Poisson ratio of roller to screw, F ₀ Is an axial force.

6. The special vehicle rapid exhibition cooperative control method according to claim 4, wherein: the process of calculating the theoretical bearing capacity of the leveling support leg in Step201 comprises

(1) The axial force and the radial force of the two front supporting legs to the frame are respectively set as f _1y 、f _1x 、f _1z (ii) a The axial force and the radial force of the two rear supporting legs to the frame are respectively f _2y 、f _2x 、f _2z (ii) a A vehicle body pitch angle alpha and a vehicle body roll angle beta; the left-right span of the two front supporting legs is h, and the span of the two rear supporting legs is the same as that of the two front supporting legs; the span of the front and rear supporting legs on the same side is l; mass of the frame is m ₁ The load mass is m ₂ The total mass is m; the center of mass of the frame is positioned in the vertical symmetrical plane of the vehicle body and has a horizontal distance of l from the central axis of the rear leg ₁ (ii) a The load mass center is positioned in the vertical symmetrical plane of the car body and has a horizontal distance of l from the central axis of the rear leg ₂ (ii) a The gravity acceleration is g-9.8 m/s ² ；

(2) Tracking the balance between the gravity of the frame and the axial force of the supporting legs when the state of the vehicle body changes by taking the plane of the frame as a reference, and listing a balance equation; the resultant force in the axial direction of the supporting leg is equal to the projection of the frame and the load gravity in the axial direction of the supporting leg; when the vehicle body has both a pitch angle and a roll angle, the stress balance equation is as follows:

f _1y +f _2y ＝mgcosαcosβ

f _1x +f _2x ＝mgsinα

f _1z +f _2z ＝mgsinβ

and (3) carrying out moment balance analysis by taking a connecting line of the two front supporting legs as a rotating shaft, wherein a moment balance equation is as follows:

[m ₁ g(l-l ₁ )+m ₂ g(l-l ₂ )]cosαcosβ＝f _2y l

and (3) carrying out moment balance analysis by taking a connecting line of the two rear supporting legs as a rotating shaft, wherein a moment balance equation is as follows:

[m ₁ gl ₁ +m ₂ gl ₂ ]cosαcosβ＝f _1y l。

7. the special vehicle rapid exhibition cooperative control method according to claim 4, wherein: the leveling control strategy based on interference compensation described in Step202 comprises

Step2021, calculating initial error as feedforward compensation, feedback control using self-adaptive fuzzy PID control, obtaining input error e of fuzzy controller according to feedforward interference compensation value, and calculating error change rate e _c ；

Step2022. fuzzy controller in operation by constantly updating e and e _c To adjust delta K _p 、ΔK _I And Δ K _D The online self-tuning of PID parameters is realized, and different e and e are met _c Different requirements for control parameters;

wherein, the input and output linguistic variables e, e of the fuzzy controller _c 、ΔK _p 、ΔK _I 、ΔK _D All of the ambiguity domains of [ -6, 6 [)]The fuzzy subset is [ NB, NM, NS, ZO, PS, PM, PB]And considering the coverage degree, sensitivity, stability and robustness principle of the domain of interest, each fuzzy subset adopts a Gaussian-shaped membership function.

8. The special vehicle rapid exhibition cooperative control method according to claim 1, characterized in that: the control process of the special vehicle collaborative erecting method based on the high-pressure energy storage comprises the Step of Step3

Step3011, adopting a scheme that a high-pressure accumulator drives a special vehicle to quickly erect, and establishing the high-pressure accumulator;

step3012, establishing a three-level hydraulic cylinder mathematical model on the basis of the high-pressure accumulator;

and Step3013, establishing a mathematical model of the buffer device on the basis of the mathematical model of the three-level hydraulic cylinder.

9. The special vehicle rapid exhibition cooperative control method according to claim 8, characterized in that: the establishing process of the three-level hydraulic cylinder mathematical model in the Step3012 comprises

(1) Respectively using the positive and negative cavities of hydraulic cylinder as a node cavity, establishing a pressure equation of two cavities by node cavity method, calculating the output force of each cylinder, and obtaining a mathematical model of three cylinders, such as

In the formula, E is the effective volume elastic modulus of the oil; v _f And V _b Respectively the initial volumes of the positive cavity and the negative cavity of the multi-stage cylinder; q _f And Q _b Respectively the flow rate of the fluid flowing into or out of the positive cavity and the negative cavity; a. the _f3 、A _f2 、A _f1 The action areas of the positive cavities of the 3-stage, 2-stage and 1-stage cylinders are respectively; a. the _b3 、A _b2 、A _b1 Respectively the reaction areas of the 3-stage cylinder, the 2-stage cylinder and the 1-stage cylinder; l. the _3max 、l _2max 、l _1max Maximum displacement of 3, 2, 1 stage cylinders respectively; p is a radical of _f 、p _b The pressures of the positive cavity and the negative cavity of the oil cylinder are respectively; x is the number of ₃₂ 、v ₃₂ Axial displacement and speed of the 3-stage cylinder relative to the 2-stage cylinder are respectively; x is the number of ₂₁ 、v ₂₁ Axial displacement and speed of the 2-stage cylinder relative to the 1-stage cylinder are respectively; x is the number of _1p 、v _1p Axial displacement and speed of the 1-stage cylinder relative to the piston rod are respectively; f ₃ 、F ₂ 、F ₁ The output acting force of the 3-stage cylinder, the 2-stage cylinder and the 1-stage cylinder are respectively output; f _f3 、F _f2 、F _f1 Friction forces in the operation processes of the 3-stage cylinder, the 2-stage cylinder and the 1-stage cylinder are respectively; f _p3 、F _p2 、F _p1 The collision force among the 3-stage cylinder, the 2-stage cylinder and the 1-stage cylinder and the piston rod is respectively;

(2) the friction force model in the cylinder operation in the formula (40) adopts an improved LuGre model, and a mathematical model such as

Wherein z is the average elastic deformation of the bristles; v is the relative velocity of the contact surface; sigma _z Is the stiffness coefficient; tau is _z Is a damping coefficient; eta _z Is the viscosity coefficient; v. of _s Is the Stribeck velocity constant; f _c Coulomb friction; f _s Is static friction force; h is the thickness of the oil film;

(3) the model of the hydraulic cylinder interstage impingement in equation (40) is based on a Hertz contact force model, the mathematical model of which is as follows

In the formula, K _p And K _n Is the equivalent spring rate; μ is a hysteresis factor; delta is the contact point normal penetration depth; v. of _R And v _c The speed of the two cylinders; x is the relative displacement between the cylinder barrels; g _p The upper limit of the displacement of the cylinder barrel; g is a radical of formula _n The lower bound of cylinder displacement.

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