CN111745369A - Large-scale cabin docking method for real-time monitoring - Google Patents

Abstract

A large cabin segment butt joint method for real-time monitoring comprises the following steps of: defining entity pose information, inputting precision information and establishing a collision detection model of the pin body and the hole surface; and performing an access docking process after the docking preparation is completed, updating the entity pose according to the real-time sensor and the equipment motion data in the process, and searching the docked track segment, pin hole external pose adjustment and pin hole docking based on the real-time pose information. The invention adopts a common rail transfer serial bracket type trolley in a docking workshop, is matched with a large-size digital measurement technology, realizes closed-loop control through online monitoring, completes docking according to procedures of searching a docking rail section, adjusting the posture outside a pin hole and docking the pin hole, and obviously improves the docking efficiency and quality consistency of a large cabin section.

Description

Large-scale cabin docking method for real-time monitoring

technical field

The invention relates to a technology in the field of spacecraft manufacturing, in particular to a real-time monitoring-oriented large-scale cabin section docking method.

Background technique

The docking process of the cabin is shown in Figure 1: the cabin is a cylindrical structure, and the product is composed of multiple sections. Each section is positioned by positioning pins. After the docking is completed, the final connection is achieved by bolts or studs. During the docking process, the cabin is installed on the attitude adjustment equipment, and the attitude adjustment equipment adjusts the attitude of the cabin so that the positioning pin matches the positioning hole to reach the position required by the assembly design.

At present, the rocket assembly adopts the production mode of "multi-model parallel, single-piece small batch", and the entire assembly process is carried out in one station. As a core link in the rocket assembly process, the docking of the cabin is complicated and requires high precision. Tracks are laid in the traditional workshop, and the attitude-adjusting frame truck is transferred to the docking position through the track, and then the docking is completed through manual coordination and manual adjustment of the frame vehicle, which is inefficient and low in quality consistency. The existing solutions are often designed for complex and high-precision parallel attitude adjustment equipment to achieve automatic docking, but the parallel attitude adjustment equipment is large, and the docking time is shortened when multiple docking is performed in the above scenarios, but the transport and preparation time of the cabin is relatively long. long.

SUMMARY OF THE INVENTION

Aiming at the above-mentioned shortcomings of the prior art, the present invention proposes a real-time monitoring-oriented large-scale cabin docking method, which adopts the common rail transfer series bracket-type trolley in docking workshops, and cooperates with large-scale digital measurement technology to realize closed-loop through online monitoring. Control and complete the docking according to the process of finding the docking track section, adjusting the attitude outside the pin hole, and docking the pin hole, which significantly improves the docking efficiency and quality consistency of large cabins.

The present invention is achieved through the following technical solutions:

The invention relates to a real-time monitoring-oriented large-scale cabin docking method. First, in the preparation stage, the following steps are performed: (1) define entity pose information, (2) input accuracy information, and (3) establish a collision detection model between a pin body and a hole surface; Carry out the docking process. In the process, the entity pose is updated according to the real-time sensor and equipment motion data, and based on the real-time pose information, ⑤ finds the track segment for docking, ⑥ adjusts the attitude outside the pin hole, and ⑦ docks the pin hole.

The defined entity pose information refers to: the coordinates of the input position sensor in the coordinate system of the measuring tool, obtained according to the three-point method; when the input measuring tool is installed on the cabin, the pose of the cabin in the coordinate system of the measuring sensor; According to the posture adjustment structure composed of the track, the carriage and the tooling ring, the mapping of the motion joints to the position and posture of the track, the travelling member of the carriage, the traversing member of the carriage, the lifting member of the carriage, and the tooling ring is obtained;

The input precision information refers to: inputting the allowable position error and angle error of the docking; inputting the control precision of the crane.

The establishment of the collision detection model between the pin body and the hole surface refers to: input the pose of the docking corresponding pin and the hole on the cabin section, as well as the pin radius, pin length, hole radius, and hole depth, and establish the pin body and hole surface. Parametric equation; and use the parametric equation to divide the space octree to establish a collision detection model;

The updated entity pose refers to: after the carriage is installed with the cabin section and the measurement tooling is installed in the cabin, the carriage control system and the measurement system respectively send the motion data of the four joints of the four carriages and the position data of the measurement sensor in real time. , During the docking process, the positions and postures of the tooling, cabin section, carriage traveling member, carriage traversing member, carriage lifting member and tooling ring are calculated and measured according to the data, and updated in real time.

The said finding the track segment for docking refers to: calculating the margin according to the historical attitude adjustment results of the maximum position error and angle error, the control accuracy of the trolley, and the allowable position error and angle error of the docking, as the allowable track factor in the docking process. The first cabin is moved by the trolley, and the real-time feedback of the cabin pose changes is used to find a track, and the position and angle deviation brought by this track is less than the error margin.

The above-mentioned attitude adjustment outside the pin hole refers to: the second cabin moves into the track segment found, the real-time Euler angle of the first cabin is used as feedback, the ideal docking position is input, and the carriage does not move in the direction of the track. Control the motion pair speed of the trolley to adjust the pose of the first cabin segment.

The pin-hole docking refers to: the first cabin section moves along the track, updates the spatial octree established in the collision detection model between the pin body and the hole surface, performs collision detection, and alarms when the pin hole collides.

The present invention relates to a system for implementing the above method, comprising: a communication interface module, a pose calculation module, a 3D visualization module, a collision detection module, and a process control module. The communication interface module collects the motion data of the control system, and forwards the position data of the measurement system to the pose calculation module, and forwards the control instructions of the process control module to the control system; the pose calculation module is connected with the communication interface model, and calculates the entity pose according to the real-time data; The 3D visualization module updates the 3D model according to the pose information and displays real-time information; the collision detection module updates the collision detection model according to the entity pose and outputs the collision detection results; the process control module controls the search for docking track segments and pins according to the entity pose and collision detection results. Out-of-hole attitude adjustment and pin-hole docking process, and output control commands.

technical effect

The invention as a whole solves the problems of low assembly efficiency, insufficient quality consistency and excessive coercive deformation when the prior art uses rails, series bracket attitude adjustment equipment and tooling rings to adjust the attitude manually.

Compared with the prior art, the present invention utilizes large-scale positioning technology to measure the position and attitude of the cabin, forms closed-loop control based on real-time position and attitude information, and realizes automatic attitude adjustment; Pin-hole docking to ensure the automatic process; based on real-time monitoring of cabin position and equipment movement, calculate the impact of track unevenness on docking, and find a suitable track segment to complete the docking process; replace pins and cylindrical surfaces with cylinders Hole and surface, establish a spatial octree according to the parametric equation, perform real-time collision detection, and alarm when a collision occurs, that is, forced deformation; the system applies 3D modeling technology to establish 3D models for each physical object of the docking system, and performs mapping processing, the scene is realistic, real-time The update is helpful for personnel to grasp the connection details.

Description of drawings

Figure 1 is a schematic diagram of the docking process of the cabin;

Figure 2 is a diagram of a large-scale cabin docking system for real-time monitoring;

Fig. 3 is the docking flow chart of the present invention oriented to real-time monitoring;

Figure 4 is a structural diagram of an attitude adjustment mechanism;

Figure 5 is a schematic diagram of the docking site.

Detailed ways

As shown in Figure 2, this embodiment specifically includes the following steps:

Step 1. Define the entity pose information, including the pose of the measurement tool under the measuring point coordinate system, the pose of the cabin under the measurement tool, the motion model of the attitude adjustment equipment, and the ideal docking position of the first cabin relative to the second cabin. ,Specifically:

{A₁}为第一舱段测量工装固连坐标系，{A₂}为第二舱段测量工装固连坐标系。以

为X轴、

为Z轴、

为原点的测点坐标系{S_k}在{A_k}中的位姿为

设

则：

测量工装{A_k}在测点坐标系{S_k}下的位姿为

1.1) Set the coordinates of the position sensor under the coordinates of each measurement tooling fixed coordinate system {A _k } as:

{A ₁ } is the fixed coordinate system of the measurement tool in the first cabin section, and {A ₂ } is the fixed coordinate system of the measurement tool in the second cabin section. by

for the X-axis,

for the Z axis,

The pose of the measuring point coordinate system {S _k } in {A _k }, which is the origin, is

Assume

but:

The pose of the measuring tool {A _k } under the measuring point coordinate system {S _k } is:

1.2) According to the measurement tooling and cabin installation drawings, define the pose of the fixed connection coordinate system {C _k } of the cabin in the measurement tool fixed coordinate system {A _k }:

则各构件位姿矩阵与关节量

的关系满足：

其中：sθ_i＝sinθ_i，cθ_i＝cosθ_i。1.3) According to the attitude adjustment structure composed of the track, attitude adjustment equipment and tooling ring, as shown in Figure 4, the motion model is obtained: set the track, the walking component, the traverse component, the lifting component, and the tooling ring, and the fixed coordinate system of each is {0 }{1}{2}{3}{4}, forming a translation pair X, a translation pair Y, a translation pair Z, and a rotation pair A in sequence. The direction of the coordinate axis of each component is the same as {L}. In the figure, l ₁ =0. According to the layout of the factory building, the pose of {0} in the global coordinate system is

Then the pose matrix and joint quantity of each component

The relationship satisfies:

where: sθ _i =sinθ _i , cθ _i =cosθ _i .

1.4) Determine the pose of the first cabin section relative to the second cabin section at the design position when fully docked:

Step 2) Input the accuracy information: determine the allowable position error _Ed and angle error E _θ of the docking according to the assembly requirements, and input the control accuracy ε of the movement pair of the attitude adjustment mechanism.

对应销P_i销半径、长度、在舱段上的位姿

建立孔面，销圆柱体面的参数方程，以此对孔面、销圆柱体面进行八叉树空间分割，得到对应的八叉树空间模型，最小单元的边长为

Step 3) Establish an octree collision detection model according to the hole and pin parameters: input the hole diameter, hole depth, and pose on the cabin of the hole H _i on the flange.

Corresponding pin P _i pin radius, length, pose on the cabin

The parametric equations of the hole surface and the pin cylinder surface are established, and the octree space is divided into the hole surface and the pin cylinder surface, and the corresponding octree space model is obtained. The edge length of the minimum element is

Input 1) At the docking site, install the first cabin section and the second cabin section on the active and driven carriages respectively through the tooling ring. The carriages are located on the same track, and the cabin section is installed with measurement tooling. The scene diagram is shown in Figure 5. After the installation is completed, start the docking process and go to step 5). The carriage control system and the pose measurement system send the four kinematic joints of the carriage XYZA and the position of the position sensor in the global coordinate system to the interface in real time. The frequency is 30Hz. Step 4) Update the entity pose according to the real-time data.

Step 4) Update entity pose: The specific way of updating the entity pose is as follows:

则：

得到测量工装{A_k}在全局坐标系{W}下的位姿：

其中：

为工装{A_k}在测点坐标系{S_k}下的位姿。4.1) Measurement tooling pose update: obtain the real-time position data of the position sensor in the global coordinate system {W} according to the interface: ^W p _ki , i=1, 2, 3, k=1, 2. Let the pose of {S _k } in {W} be

but:

Obtain the pose of the measuring tool {A _k } in the global coordinate system {W}:

in:

is the pose of the tooling {A _k } in the measuring point coordinate system {S _k }.

其中：

为舱段固连坐标系{C_k}在测量工装固连坐标系{A_k}的位姿。4.2) Update of the cabin pose: the pose of the fixed coordinate system {C} of the cabin in the global coordinate system {W}

in:

It is the position and attitude of the fixed coordinate system {A _k } of the measuring tool for the fixed coordinate system {C _k } of the cabin.

由步骤1.3)中各构件位姿矩阵与关节量的关系，得到构件固连坐标系在全局坐标系{W}的位姿。4.2) Docking device component pose update: obtain the real-time value of the motion pair according to the interface

From the relationship between the pose matrix of each component and the joint amount in step 1.3), the pose of the component fixed coordinate system in the global coordinate system {W} is obtained.

Step 5) Find the docking track segment: the specific steps are as follows

CE_θ＝E_θa+E_θr，其中：C为裕度系数，小于1；E_da与E_θa为历史调姿结果位置误差和角度误差最大值，根据上述公式计算获得销孔对接轨道容许误差E_dr和E_θr。5.1) Calculation of track segment requirements: Considering the influence of the external attitude adjustment error E _a of the pin hole and the track error E _r of the pin hole docking on the docking process, the assembly allowable error is decomposed into

CE _θ =E _θa +E _θr , where: C is the margin coefficient, less than 1; E _da and E _θa are the maximum position error and angle error of the historical attitude adjustment results, and the allowable error E of the pin-hole docking track is calculated according to the above formula _dr and E _θr .

The requirements for obtaining the track segment AB are:

1) The maximum difference in the YZ direction is less than E _dr ;

2) The maximum angle difference is less than E _θr ;

3) The AB distance is greater than or equal to 6 times the pin length L.

5.2) Find track segments that meet the requirements:

S_p、S_θ初始化为空，第一舱段位姿为

求逆获得

第一舱段的主动、从动架车同步沿轨道向低速运动。①Set two sequences S _p ={pi ,…p _j },S _θ ={θ _i ,…θ _j }, p _i =(x _i ,y _i ,z _i ), θ _i =(α _{i ,} β _i ,γ _i ) variables

S _p , S _θ are initialized to be empty, and the pose of the first cabin segment is

get inverse

The active and driven carriages of the first cabin move synchronously along the track to a low speed.

计算相对初始位置的位姿变化量

ΔT分解为位移p_j+1和旋转矩阵R_j+1,将轴线e_x＝(0,0,0)旋转得到θ_j+1＝R_{j+ 1}e_x。②Collect the pose of the current first cabin segment

Calculate the pose change relative to the initial position

ΔT is decomposed into displacement p _j+1 and rotation matrix R _j+1 , and the axis ex =(0,0,0) is rotated to obtain θ _j+1 =R _{j+ 1 e x .}

③p _j+1 and θ _j+1 , add Sp and S _θ respectively, j ₌ j+1, update

S_p和S_θ分别删除p_i和θ_i，i＝i+1，执行步骤⑤；当x_j-x_i+1<6L且x_j-x_i≥6L，执行步骤⑤。④ When x _j - x _i <6L, wait for the next data to be collected and perform step ②; when x _j - x _i+1 ≥ 6L, update

S _p and S _θ delete p _i and θ _i respectively, i=i+1, go to step ⑤; when x _j - x _i+1 <6L and x _j - x _i ≥ 6L, go to step ⑤.

S_θ内任意θ_k有

则舱段x_i至x_j位置对应轨道AB满足对接，否则等待采集下一步数据执行步骤②。⑤When any _{p k} in Sp has

Any θ _k within S _θ has

Then the position of the cabin segment x _i to x _j corresponds to the track AB to meet the docking, otherwise wait for the next data to be collected to perform step ②.

Step 6) Adjust the posture outside the pin hole, including:

6.1) The active and driven carriages of the first cabin section synchronously retreat along the track to the position where the cabin section coordinates are x = x _A + L,

第二舱段的主动、从动架车同步沿轨道运动，直到第二舱段位置X分量与p_aim2相同，并以第二舱段当前位姿

作为对接目标，求得理想对接时第一舱段位姿为：

将

分解为(X_a,Y_a,Z_a,α_a,β_a,γ_a)，其中：α_a,β_a,β_a为X-Y-Z欧拉角计算所得。6.2) Calculation

The active and driven carriages of the second cabin move synchronously along the track until the position X component of the second cabin is the same as p _aim2 , and the current position of the second cabin

As the docking target, the pose of the first cabin during ideal docking is obtained as:

Will

It is decomposed into (X _a , Y _a , Z _a , α _a , β _a , γ _a ), where: α _a , β _a , β _a are calculated from XYZ Euler angles.

6.3) Using the real-time Euler angles (α, β, γ) of the first cabin as feedback, adjust the angular velocity control α of the rotating pair A synchronously according to the active and driven carriages, and adjust the speed of the moving pair Z to control β on the contrary, and adjust the moving pair on the contrary. Y speed control γ, synchronously adjust the mobile pair Y speed control y, synchronously adjust the mobile pair Z speed control z, and adjust the posture of the carriage.

Step 7) Pin-hole docking: The active and driven carriages of the first cabin move synchronously along the track at a low speed, and update the hole-pin octree model of the moving side in real time. Real-time collision detection is performed on the corresponding hole pin using its octree. After the collision is detected, the docking is stopped and an alarm is issued, and the operator intervenes to solve it.

To sum up, in this embodiment, before the formal docking, the track docking section requirements are calculated according to the historical attitude adjustment accuracy and the docking requirement accuracy, and then the track section that meets the requirements is found by monitoring the changes of the real-time pose data of the cabin section during the slow motion of the carriage. , to prevent the docking section from becoming larger due to the orbital factor after the attitude adjustment and the complete docking of the pin holes, and also to prevent the unevenness of the track from causing the assembly stress to increase when the pin holes are finally docked. In this embodiment, a spatial octree collision model is established based on the pin body and hole surface parameter equations, real-time collision detection is performed during the docking process, and an alarm occurs when a collision occurs, and the staff can choose follow-up measures according to the assembly deformation.

Compared with the prior art, this method is based on the original method of the workshop, and the single docking time is reduced from one hour to ten; in the single-station assembly docking production scenario, docking can be performed in situ without the need for back and forth transport.

The above-mentioned specific implementation can be partially adjusted by those skilled in the art in different ways without departing from the principle and purpose of the present invention. The protection scope of the present invention is subject to the claims and is not limited by the above-mentioned specific implementation. Each implementation within the scope is bound by the present invention.

Claims (9)

1. A large-scale cabin docking method for real-time monitoring is characterized in that, at first in the preparation stage, carry out in turn: define entity pose information, input accuracy information, and establish a collision detection model between the pin body and the hole surface; After completing the docking preparation Carry out the docking process. In the process, the entity pose is updated according to real-time sensors and equipment motion data, and based on the real-time pose information, the docking track segment, the external attitude adjustment of the pin hole, and the docking of the pin hole are used. Bracket-type trolley, combined with large-scale digital measurement technology, realizes closed-loop control through online monitoring, and completes the docking according to the process of finding docking track sections, adjusting the attitude outside the pin holes, and docking the pin holes, which significantly improves the docking efficiency and quality consistency of large cabin sections. . 2. The real-time monitoring-oriented large-scale cabin docking method according to claim 1, wherein the defined entity pose information refers to: the input position sensor measures the coordinates of the tooling coordinate system, and obtains according to the three-point method ;Enter the position and posture of the cabin in the coordinate system of the measuring sensor when the measuring tool is installed on the cabin; According to the attitude adjustment structure composed of the track, the carriage and the tooling ring, the motion joints are measured to the track, the travelling member of the carriage, and the frame. Mapping of vehicle traversing components, carriage lifting components, and tooling ring poses. 3 . The real-time monitoring-oriented large-scale cabin docking method according to claim 1 , wherein the input precision information refers to: input docking allowable position error and angle error; input crane control precision. 4 . 4. The real-time monitoring-oriented large-scale cabin docking method according to claim 1, wherein the described collision detection model for establishing the pin body and the hole surface refers to: input docking corresponding pins and holes on the cabin section. Pose, as well as pin radius, pin length, hole radius, and hole depth, establish the parametric equations of the pin body and hole surface; and use the parametric equation to perform space octree segmentation to establish a collision detection model. 5. The real-time monitoring-oriented large-scale cabin docking method according to claim 1, wherein the updated entity pose refers to: after the carriage is installed with the cabin section and the measurement tooling is installed in the cabin, the carriage is mounted on the carriage. The control system and the measurement system respectively calculate the motion data and position data of each of the four joints of the four trolleys in real time, and calculate and measure the tooling, cabin section, traveling components of the trolley, traverse components, and lifting components of the trolley according to the data during the docking process. and the pose of the tooling ring, and updated in real time. 6. The real-time monitoring-oriented large-scale cabin section docking method according to claim 1, wherein the described track section for seeking docking refers to: position error and angle error maximum value and docking allowable position according to historical attitude adjustment results Error and angle error, calculate the margin, as the influence of the allowable orbital factors in the docking process; move the first cabin section by the trolley, and use the real-time feedback of the cabin section posture changes to find a section of orbit, the position brought by this section of orbit and the angular deviation is less than the error margin. 7. The real-time monitoring-oriented large-scale cabin docking method according to claim 1, wherein the external attitude adjustment of the pin hole refers to: the second cabin is moved into the found track section, and the real-time The Euler angle is used as the feedback, the ideal docking position is the input, the trolley does not move in the direction of the track, and the posture of the first cabin is adjusted by controlling the motion pair speed of the trolley. 8. The real-time monitoring-oriented large-scale cabin docking method according to claim 1, wherein the pin-hole docking refers to: the first cabin section moves along the track, and the collision detection model between the pin body and the hole surface is updated. The spatial octree established in , does collision detection, and alarms when the pin hole collides. 9. A system for implementing the method according to any of the preceding claims, characterized in that it comprises: a communication interface module, a pose calculation module, a 3D visualization module, a collision detection module, a process control module, and a communication interface module acquisition control system The motion data and the position data of the measurement system are forwarded to the pose calculation module, and the control instructions of the process control module are forwarded to the control system; the pose calculation module is connected with the communication interface model, and the entity pose is calculated according to the real-time data; the 3D visualization module is based on the pose The information updates the 3D model and displays real-time information; the collision detection module updates the collision detection model according to the entity pose and outputs the detection results; the process control module controls the search for the docking track segment, the external attitude adjustment of the pin hole and the pin hole according to the entity pose and collision detection results. The docking process outputs control instructions.

Images