CN116909199B - A control method for reconfigurable drones based on link configuration - Google Patents

Abstract

The invention discloses a control method for a reconfigurable unmanned aerial vehicle based on link configuration. The reconfigurable unmanned aerial vehicle includes a reconfiguration controller, a BSTSMC controller arranged in an attitude ring, and an expansion state connected to the BSTSMC controller. observer; the control method includes: the reconstruction controller reconstructs the reconfigurable UAV according to the received reconstruction signal; the expanded state observer obtains the attitude change information of the reconstructed reconfigurable UAV, and The attitude change information compensates the attitude of the reconfigurable UAV in real time; the BSTSMC controller obtains the real-time compensated attitude control signal and adjusts the attitude of the reconfigurable UAV in real time based on the attitude control signal. In the case of time-varying physical properties of the reconfigurable UAV and the presence of model uncertainty and external disturbances, the disturbances can be estimated and compensated in real time to achieve synchronous deformation during flight and maintain reliable flight performance.

Description

A control method for a reconfigurable UAV based on link configuration

Technical Field

The present invention belongs to the technical field of unmanned aerial vehicle control, and in particular relates to a control method of a reconfigurable unmanned aerial vehicle based on connecting rod configuration.

Background Art

Reconfigurable UAVs can reconfigure their own shapes during flight to adapt to the environment, thereby expanding their scope of application. The change in their own shape will greatly affect the attribute parameters of the UAV and cause great interference to the UAV's attitude. For under-actuated systems such as rotorcraft UAVs, the interference of attitude will also be reflected in the position. At this time, the UAV will enter a short-term unstable state, which does not meet the requirements of stable control in practical applications. In order to reduce the attitude interference during UAV reconstruction, researchers have proposed many improved control algorithms. Most of the literature estimates the time-varying parameters by designing adaptive laws and compensates them in real time to the nonlinear control rate derived from the model. Although this method effectively reduces the interference caused by reconstruction, the introduction of the adaptive law increases the control method's dependence on the model accuracy, and the interference source targeted is relatively single, which is not conducive to the universality of the control algorithm.

Summary of the invention

The present invention provides a control method for a reconfigurable UAV based on a connecting rod configuration, which is used to solve the technical problem that a large attitude interference may be generated when the reconfigurable UAV is reconfigured during flight.

The present invention provides a control method for a reconfigurable UAV based on a link configuration, wherein the reconfigurable UAV comprises a reconfiguration controller, a BSTSMC controller arranged in an attitude loop, and an extended state observer connected to the BSTSMC controller; the control method comprises:

The reconfiguration controller reconfigures the reconfigurable UAV according to the received reconfiguration signal, wherein when a certain arm is deformed, the expression of the minimum limiting angle of the reconfigurable UAV is: ,

When two adjacent arms are deformed in combination and any three or all arms are deformed, the expression of the maximum limit angle of the reconfigurable UAV is: ,

In the formula, , are the minimum and maximum limit angles of the arm rotation during the reconstruction of the UAV, is the distance from the connection point between the connecting rod and the motor to the root of the blade, is the rotor diameter, is the diagonal length of the body, is the length of the machine arm;

The extended state observer obtains the attitude change information of the reconfigurable UAV after reconstruction, and performs real-time compensation on the attitude of the reconfigurable UAV according to the attitude change information;

The BSTSMC controller obtains the attitude control signal after real-time compensation, and adjusts the attitude of the reconfigurable UAV in real time according to the attitude control signal. The expression of the BSTSMC controller is:

,

In the formula, is the total control quantity, is the control quantity based on the backstepping method, is the control quantity of the superhelix control algorithm, is a set of adjustable gains, is the total disturbance of each channel observed by the extended state observer, is the error between the expected value and the feedback value, is the expected value, is the error differential gain, is the differential of the error, is the sliding surface gain, is the sliding surface, is the superhelical coefficient, is the symbolic function, is the superhelical coefficient, The current running time.

Furthermore, when the two diagonal arms are combined and deformed, the expression of the maximum limit angle of the reconfigurable UAV is:

.

Furthermore, the expression of the extended state observer is:

,

In the formula, For the Tracking error at any time, For the The tracking feedback amount of the momentary roll channel, For the The tracking feedback amount of the momentary roll channel, For the The rolling angle of the drone at the moment, is the observer step size, For the The differential of the tracking feedback amount of the moment roll channel, For the The differential of the tracking feedback amount of the moment roll channel, For the The disturbance observation of the moment rolling channel, For the The disturbance observation of the moment rolling channel, , , are the observer adjustable gains, is a nonlinear function with a coefficient of 0.5, is the output feedback gain, For the The controller output of the momentary roll channel, is a nonlinear function with a coefficient of 0.25;

,

In the formula, The coefficient is The nonlinear function of is the independent variable, is the minimum value, is a symbolic function.

Furthermore, the posture change information includes a change in center of gravity and a change in inertia.

Furthermore, assuming that the geometric center of the reconfigurable UAV before reconstruction is the origin, the expression of the change in the center of gravity of the reconfigurable UAV is:

,

In the formula, is the center of gravity offset, is the mass of the fuselage and servo, is the vector from the center of gravity of the fuselage to the origin of the coordinate system, is the total couple of the arm, rotor and rotor, is the mass of the arm, is the motor mass, is the rotor mass, For the The vector from the center of gravity of the arm to the origin of the coordinate system, For the The vector from the motor center of gravity to the coordinate origin, For the The vector from the rotor center of gravity to the coordinate origin.

Furthermore, the expression of the inertia change of the arm of the reconfigurable UAV is:

,

In the formula, is the reconstructed inertia of the first and third arms, is the rotation matrix around the y axis, is the inertia of the arm when it is not reconstructed, is the transpose of the rotation matrix around the y-axis, is the reconstructed inertia of the second and fourth arms, is the rotation matrix around the x-axis, is the transpose of the rotation matrix around the x-axis;

in, ,

In the formula, is the cosine value of the rotation angle of the second and fourth arms, is the sine value of the rotation angle of the second and fourth arms;

,

In the formula, is the cosine value of the rotation angle of the first and third arms, is the sine of the rotation angle of the first and third arms.

Furthermore, the expression of the reconstruction controller is:

,

In the formula, For the The angular velocity of the arm, For the Gain of independent deformation channels, For the The desired angle of the arm, For the The current angle of the arm.

The control method of the reconfigurable UAV based on the link configuration of the present application adopts a cascade control framework of a BSTSMC controller and an extended state observer connected to the BSTSMC controller. The control framework reduces the dependence on model accuracy. When the physical properties of the reconfigurable UAV vary with time and there are model uncertainties and external disturbances, the disturbance can be estimated and compensated in real time to achieve synchronous deformation during flight and maintain reliable flight performance.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

FIG1 is a flow chart of a control method of a reconfigurable UAV based on a link configuration provided by an embodiment of the present invention;

FIG2 is a diagram showing the definition and limitation of the size of a reconfigurable drone according to a specific embodiment of the present invention;

FIG3 is a simulation diagram of a reconstruction control of a specific embodiment provided by an embodiment of the present invention;

FIG4 is a trajectory tracking simulation diagram of a specific embodiment provided by an embodiment of the present invention;

FIG5 is a position control response diagram of a specific embodiment provided by an embodiment of the present invention;

FIG6 is a posture control response diagram of a specific embodiment provided in one embodiment of the present invention;

FIG. 7 is a diagram of coping with position interference during reconstruction according to a specific embodiment of the present invention;

FIG8 is a diagram of coping with posture interference during reconstruction according to a specific embodiment of the present invention.

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Please refer to Figure 1, which shows a flow chart of a control method of a reconfigurable UAV based on a link configuration of the present application. The reconfigurable UAV includes a reconfiguration controller, a BSTSMC controller arranged in an attitude loop, and an extended state observer connected to the BSTSMC controller.

As shown in FIG1 , the control method of the reconfigurable UAV based on the link configuration specifically includes the following steps:

Step S101: a reconstruction controller reconstructs the reconfigurable UAV according to a received reconstruction signal.

In this step, the expression of the reconstructed controller is:

,

In the formula, For the The angular velocity of the arm, For the Gain of independent deformation channels, For the The desired angle of the arm, For the The current angle of the arm.

Specifically, four brushless motors are used to provide thrust for the drone, and four servo motors are fixed to the body to drive the four arms to move independently, thus building a modular reconfigurable drone.

The final reconfigured shape of the reconfigurable drone is composed of the deformation of four independent arms. The deformation principle of each arm is the same. The following takes one of the arms as an example to illustrate the parallelogram shown in Figure 2. In order to facilitate expression, all mechanical components are abstracted as line segments for illustration. Represents connecting rod, line segment Represents the arm, line segment Represents the body, line segment Represents the motor and rotor, The thrust vector generated for each individual rotor. for The state after deformation, where and The movement between is active movement, driven by the steering gear, and the rest of the movement is passive movement under the constraint of the parallelogram. It can be seen that the parallel connecting rod structure proposed in this application can ensure The direction is always Parallel means perpendicular to the horizontal plane of the aircraft.

When a single arm is deformed, the horizontal plane of the body is zero degrees, downward is negative, and the The current angle of the arm for When multiple arms are combined and deformed, overlap between the rotor and the connecting rod or the rotor will occur. The situation during the combined deformation is analyzed and the following restrictions are imposed on the rotation angle.

The minimum limit of the arm rotation angle occurs when the arm rotates downward. When a certain angle is reached, the blades will overlap with the connecting rod. When a certain arm is deformed, the expression of the minimum limit angle of the reconfigurable drone is:

,

In the formula, The minimum limit angle of arm rotation when reconstructing the drone, is the distance from the connection point between the connecting rod and the motor to the root of the blade, is the rotor diameter.

When analyzing the maximum limiting angle, there are three combined deformation situations:

1) When the two diagonal arms are combined and deformed, the following relationship needs to be satisfied:

,

In the formula, is the wheelbase of the drone, is the diagonal length of the body;

If the propeller meets , then the maximum limit angle is related to the dimensions of each body.

The expression of the maximum limiting angle of the reconfigurable UAV is:

,

2) When two adjacent arms are deformed in combination, the added restriction conditions are: ,

Then the expression of the maximum limiting angle of the reconstructible drone is:

,

3) When any three or all arms are deformed, add the following restrictions:

,

Then the expression of the maximum limiting angle of the reconstructible drone is:

,

In the formula, The maximum limit angle of arm rotation when reconstructing the drone, is the rotor diameter, is the diagonal length of the body, is the arm length.

Based on the limitations obtained from the above analysis, the maximum and minimum wheelbase of the deformation range of the reconfigurable UAV is proposed to be:

,

In the formula, is the maximum wheelbase of the drone, The minimum wheelbase of the drone.

Step S102: The extended state observer obtains the attitude change information of the reconfigurable UAV after the reconstruction, and performs real-time compensation on the attitude of the reconfigurable UAV according to the attitude change information.

To describe the attitude of the reconfigurable drone, a point o is randomly selected on the ground as the origin. The X-axis points to any direction on the earth's surface, the Z-axis points to the sky along the vertical direction, and the Y-axis is perpendicular to the X-axis in the horizontal plane. The direction is determined by the right-hand rule.

The origin o of the body coordinate system is located at the center of mass of the reconfigurable UAV posture. The x-axis is in the symmetry plane of the reconfigurable UAV posture and is parallel to the design axis of the reconfigurable UAV posture, pointing to the front of the nose of the reconfigurable UAV posture. The y-axis is perpendicular to the symmetry plane of the fuselage and points to the left of the fuselage of the reconfigurable UAV posture. The z-axis passes through point o and is perpendicular to the xoy plane, pointing to the top of the reconfigurable UAV posture.

The rotation matrix from the body coordinate system to the ground coordinate system is obtained by left-multiplying the basic rotation matrix. The simplified calculation result is as follows:

,

In the formula, is the drone rotation matrix, is the pitch angle of the drone, is the roll angle of the drone, is the yaw angle of the drone;

That is, the conversion relationship between the body coordinate system and the ground coordinate system is:

,

In the formula, is the representation of a point in the ground coordinate system, is the representation of a point in the body coordinate system.

A six-degree-of-freedom mathematical model of a reconfigurable UAV is established based on the Newton-Euler equations, in which the position three-degree-of-freedom model is represented in the ground coordinate system, and the attitude three-degree-of-freedom model is represented in the body coordinate system.

,

In the formula, For drone quality, is the acceleration of the drone, is the inertia matrix of the UAV, is the angular acceleration of the drone, is the angular velocity of the drone, is the lift generated by the rotor, is the gravity of the drone, is the resistance during flight, The disturbance caused by reconstruction, is the sum of external disturbances, is the lift moment generated by the rotor, is the reaction torque generated by air resistance on the rotor, is the gyroscopic torque, The gravitational moment generated for the reconstruction;

The inertia matrix of the reconfigurable UAV will change during the deformation process. The expression of the inertia matrix of the reconfigurable UAV is:

,

In the formula, is the x-axis inertia of the drone, is the y-axis inertia of the drone, is the z-axis inertia of the drone;

The reaction torque generated by air resistance on the rotor is:

,

In the formula, is the anti-torque coefficient, For the Rotor speed;

The gyroscopic torque is:

,

In the formula, is the rotor moment of inertia, is the angular velocity of the drone around the y-axis, is the rotation speed of the first rotor, is the rotation speed of the second rotor, is the rotation speed of the third rotor, is the rotation speed of the 4th rotor, is the angular velocity of the drone around the x-axis;

The reconstructed gravity moment is as follows:

,

In the formula, is the center of gravity offset, is the rotation matrix, is the gravity of the drone;

The forces and moments generated by the rotor are related to the rotor speed as follows:

,

In the formula, is the lift generated by the rotor, is the lift moment generated by the rotor, For lift, , is the lift coefficient, when the reconfigurable UAV is reconfigured is a time-varying matrix representing the control allocation matrix, expressed as follows:

,

In the formula, is the anti-torque coefficient, For the The equivalent arm of the machine arm, .

Define the control input as follows:

,

In the formula, For high control, is the roll channel control quantity, is the pitch channel control quantity, is the yaw channel control quantity;

The six-degree-of-freedom dynamics model of the reconfigurable UAV is rewritten as:

,

In the formula, is the second-order derivative of the x position, is the second-order derivative of the y position, is the second-order derivative of the UAV roll angle, is the second-order derivative of the UAV pitch angle, is the second-order derivative of the UAV yaw angle, is the air resistance coefficient, is the yaw angle, is the first-order derivative of the x position, For drone quality, is the pitch angle of the drone, Reconstruct the perturbation for the x-position channel, is the total external disturbance of the x-position channel, is the first-order derivative of the y position, Reconstruct the perturbation for the y position channel, is the total external disturbance of the y position channel, is the acceleration due to gravity, is the first-order derivative of the height channel, is the height channel reconstruction perturbation, is the total external disturbance of the height channel, is the first-order derivative of the UAV pitch angle, is the first-order derivative of the UAV yaw angle, is the y-axis inertia of the drone, is the UAV z-axis inertia, is the x-axis inertia of the drone, is the roll channel control quantity, is the rotor inertia, is the speed difference of the four rotors, Reconstruct the disturbance for the roll angle channel, is the total external interference of the roll angle channel, is the first-order derivative of the UAV roll angle, is the pitch channel control quantity, Reconstruct the disturbance for the pitch angle, is the total external disturbance of the pitch angle, Reconstruct the disturbance for the yaw angle, is the yaw channel control quantity, is the total external disturbance of the yaw angle.

It should be noted that the reconfigurable drone includes a fuselage, a power supply, a flight control system, four steering gears, four arms, four motors and four rotors, of which the power supply, flight control system and steering gear are fixedly connected to the fuselage. The reconfigurable drone is regarded as a fuselage with a length and width of , the fuselage height is The arm is a rectangular parallelepiped, and the arm length, arm width, and arm height are respectively , , The motor and rotor are considered as a rectangular block with a motor radius of , the motor height is and the rotor radius is , rotor height is The cylinder posture change information includes the change in center of gravity and the change in inertia.

Assuming that the geometric center of the reconfigurable UAV before reconstruction is the origin, the expression of the change in the center of gravity of the reconfigurable UAV is:

,

In the formula, is the center of gravity offset, is the mass of the fuselage and servo, is the vector from the center of gravity of the fuselage to the origin of the coordinate system, is the total couple of the arm, rotor and rotor, is the mass of the arm, is the motor mass, is the rotor mass, For the The vector from the center of gravity of the arm to the origin of the coordinate system, For the The vector from the motor center of gravity to the coordinate origin, For the The vector from the rotor center of gravity to the coordinate origin.

The moment of inertia of the reconfigurable UAV is calculated using the parallel axis theorem. Specifically, the expression for calculating the moment of inertia of each part is:

,

In the formula, Reconstruct the front body inertia for the drone, Reconstruct the front arm inertia for the drone, Reconstructing the front rotor inertia for the drone, Reconstructing the front rotor inertia for drones, is the mass of the fuselage and servo, is the mass of the arm, is the motor mass, is the rotor mass;

During the deformation process, the inertia needs to be recalculated. The inertia of the cylinder does not change. The body is fixed to the coordinate system, so its inertia will not change. The following introduces the rotation matrix to represent the change in inertia of the arm of the reconfigurable drone. The expression of the change in inertia is:

,

In the formula, is the reconstructed inertia of the first and third arms, is the rotation matrix around the y axis, is the inertia of the arm when it is not reconstructed, is the transpose of the rotation matrix around the y-axis, is the reconstructed inertia of the second and fourth arms, is the rotation matrix around the x-axis, is the transpose of the rotation matrix around the x-axis;

in, ,

In the formula, is the cosine value of the rotation angle of the second and fourth arms, is the sine value of the rotation angle of the second and fourth arms;

,

In the formula, is the cosine value of the rotation angle of the first and third arms, is the sine of the rotation angle of the first and third arms.

According to the parallel axis theorem, the inertia calculation formula is:

,

In the formula, Reconstruct the inertia of the drone. is the body inertia, is the mass of the fuselage and servo, is the vector from the center of gravity of the fuselage to the origin of the coordinate system, is the center of gravity offset, For the The inertia of the arm, is the mass of the arm, For the The vector from the center of gravity of the arm to the origin of the coordinate system, is the rotor inertia, is the motor mass, For the The vector from the motor center of gravity to the coordinate origin, is the inertia of the rotor, is the rotor mass, For the The vector from the rotor to the origin of the coordinate system;

When the reconfigurable UAV is deformed, the equivalent arm force of each arm will also change. Analysis of the deformation process shows that there are two aspects of the change in the equivalent arm force. On the one hand, the deformation of the arm causes the horizontal distance from the rotor to the origin of the coordinate system to change, which can be expressed as:

,

In the formula, For the The length of the equivalent force arm without considering the center of gravity offset is is the arm length, For the The current angle of the arm, is the length of the body;

On the other hand, due to the displacement of the center caused by the deformation of the reconfigurable drone, it is assumed that the center of gravity is , then the equivalent force arm of each arm is expressed as follows:

,

In the formula, For the Equivalent force arm, is the x-axis component of the center of gravity offset, is the y-axis component of the center of gravity offset, The Z-axis component of the center of gravity offset;

The expression of the extended state observer is:

,

In the formula, For the Tracking error at any time, For the The tracking feedback amount of the momentary roll channel, For the The tracking feedback amount of the momentary roll channel, For the The rolling angle of the drone at the moment, is the observer step size, For the The differential of the tracking feedback amount of the moment roll channel, For the The differential of the tracking feedback amount of the moment roll channel, For the The disturbance observation of the moment rolling channel, For the The disturbance observation of the moment rolling channel, , , are the observer adjustable gains, is a nonlinear function with a coefficient of 0.5, is the output feedback gain, For the The controller output of the momentary roll channel, is a nonlinear function with a coefficient of 0.25;

,

In the formula, The coefficient is The nonlinear function of is the independent variable, is the minimum value, is a symbolic function.

Step S103: the BSTSMC controller obtains the attitude control signal after real-time compensation, and adjusts the attitude of the reconfigurable UAV in real time according to the attitude control signal.

In this step, the expression of BSTSMC (backstepping super spiral synovial film) controller is:

,

In the formula, is the total control quantity, is the control quantity based on the backstepping method, is the control quantity of the superhelix control algorithm, is a set of adjustable gains, is the total disturbance of each channel observed by the extended state observer, is the error between the expected value and the feedback value, is the expected value, is the error differential gain, is the differential of the error, is the sliding surface gain, is the sliding surface, is the superhelical coefficient, is the symbolic function, is the superhelical coefficient, The current time for the system to run.

Specifically, ,

In the formula, is an intermediate variable;

In the formula, is the expected value, is the feedback value, is the first-order derivative of the expected value, is the first-order derivative of the feedback value, is the first-order derivative of the expected value, is an intermediate variable.

In a specific embodiment, a simulation platform was built using Simulink to verify the proposed control algorithm. The system simulation parameters are shown in Table 1.

,

The controller parameters are shown in Table 2. The ESO parameters of the three postures are the same. The controller response speed can be adjusted. , , They are the sliding mode coefficients of the x channel, the y channel, and the z channel, respectively. The anti-disturbance capability of the position controller can be adjusted; in the BSTSMC controller The response speed of the BSTSMC controller can be adjusted. , , They are aisle, aisle, The sliding surface gain of the channel, , , , , , are the superhelical coefficients of their respective channels, , , , are the reconstructed controller gains.

,

In order to verify that the control method proposed in this application can effectively handle the disturbance caused by deformation, a trajectory tracking experiment was carried out, and the desired trajectory was set as follows during the flight:

,

In the formula, is the expected value on the x-axis, is the expected value on the y-axis, High expectations, is the current running time;

The reconstruction mechanism uses proportional control. The reconstruction angles of each arm during the experiment are shown in Figure 3, and the trajectory tracking curve is shown in Figure 4. It can be seen that the actual trajectory tracks the expected trajectory very well, verifying that the controller proposed in this application has good trajectory tracking performance.

In order to verify the response speed of the controller proposed in this application, this paper conducted position response and posture response experiments respectively. The experimental results are shown in Figures 5 and 6. It reaches a steady state within 10 seconds, which shows that the control scheme proposed in this application has a good control response speed.

This application conducted a reconstruction anti-interference experiment according to the reconstruction scheme in Figure 3. Reconstruct the four arms in order , the position deviation is shown in Figure 7. It can be seen that the position deviation is very small and returns to steady state in a very short time. Through the drone model established in the previous article, it can be found that the position deviation is caused by the attitude deviation. The attitude deviation is shown in Figure 8. It can be seen from the figure that when the reconfigurable drone is reconfigured, the attitude deviation is This indicates that the control scheme proposed in this application has good processing performance for the interference caused by the reconstruction of the reconfigurable UAV, which further verifies that the controller proposed in this application has good control effect on the reconfigurable UAV.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (7)

1. A control method for a reconfigurable UAV based on a link configuration, characterized in that the reconfigurable UAV comprises a reconfiguration controller, a BSTSMC controller arranged in an attitude loop, and an extended state observer connected to the BSTSMC controller; the control method comprises: The reconfiguration controller reconfigures the reconfigurable UAV according to the received reconfiguration signal, wherein when a certain arm is deformed, the expression of the minimum limiting angle of the reconfigurable UAV is: , When two adjacent arms are deformed in combination and any three or all arms are deformed, the expression of the maximum limit angle of the reconfigurable UAV is: , In the formula, , are the minimum and maximum limit angles of the arm rotation during the reconstruction of the UAV, is the distance from the connection point between the connecting rod and the motor to the root of the blade, is the rotor diameter, is the diagonal length of the body, is the length of the machine arm; The extended state observer obtains the attitude change information of the reconfigurable UAV after reconstruction, and performs real-time compensation on the attitude of the reconfigurable UAV according to the attitude change information; The BSTSMC controller obtains the attitude control signal after real-time compensation, and adjusts the attitude of the reconfigurable UAV in real time according to the attitude control signal. The expression of the BSTSMC controller is: , In the formula, is the total control quantity, is the control quantity based on the backstepping method, is the control quantity of the superhelix control algorithm, is a set of adjustable gains, is the total disturbance of each channel observed by the extended state observer, is the error between the expected value and the feedback value, is the expected value, is the error differential gain, is the differential of the error, is the sliding surface gain, is the sliding surface, is the superhelical coefficient, is the symbolic function, is the superhelical coefficient, The current running time. 2. According to the control method of a reconfigurable UAV based on a connecting rod configuration according to claim 1, it is characterized in that when the two diagonal arms are combined and deformed, the expression of the maximum limit angle of the reconfigurable UAV is: . 3. The control method of a reconfigurable UAV based on link configuration according to claim 1, wherein the expression of the extended state observer is: , In the formula, For the Tracking error at any time, For the The tracking feedback amount of the momentary roll channel, For the The tracking feedback amount of the momentary roll channel, For the The rolling angle of the drone at the moment, is the observer step size, For the The differential of the tracking feedback amount of the moment roll channel, For the The differential of the tracking feedback amount of the moment roll channel, For the The disturbance observation of the moment rolling channel, For the The disturbance observation of the moment rolling channel, , , are the observer adjustable gains, is a nonlinear function with a coefficient of 0.5, is the output feedback gain, For the The controller output of the momentary roll channel, is a nonlinear function with a coefficient of 0.25; , In the formula, The coefficient is The nonlinear function of is the independent variable, is the minimum value, is a symbolic function. 4. The control method of a reconfigurable UAV based on a link configuration according to claim 1, characterized in that the attitude change information includes a change in the center of gravity and a change in the inertia. 5. A control method for a reconfigurable UAV based on a connecting rod configuration according to claim 4, characterized in that, assuming that the geometric center of the reconfigurable UAV before reconstruction is the origin, the expression of the change in the center of gravity of the reconfigurable UAV is: , In the formula, is the center of gravity offset, is the mass of the fuselage and servo, is the vector from the center of gravity of the fuselage to the origin of the coordinate system, is the total couple of the arm, rotor and rotor, is the mass of the arm, is the motor mass, is the rotor mass, For the The vector from the center of gravity of the arm to the origin of the coordinate system, For the The vector from the motor center of gravity to the coordinate origin, For the The vector from the rotor center of gravity to the coordinate origin. 6. According to the control method of a reconfigurable UAV based on a connecting rod configuration as claimed in claim 4, it is characterized in that the expression of the inertia change of the arm of the reconfigurable UAV is: , In the formula, is the reconstructed inertia of the first and third arms, is the rotation matrix around the y axis, is the inertia of the arm when it is not reconstructed, is the transpose of the rotation matrix around the y-axis, is the reconstructed inertia of the second and fourth arms, is the rotation matrix around the x-axis, is the transpose of the rotation matrix around the x-axis; in, , In the formula, is the cosine value of the rotation angle of the second and fourth arms, is the sine value of the rotation angle of the second and fourth arms; , In the formula, is the cosine value of the rotation angle of the first and third arms, is the sine of the rotation angle of the first and third arms. 7. The control method of a reconfigurable UAV based on link configuration according to claim 1, characterized in that the expression of the reconfigurable controller is: , In the formula, For the The angular velocity of the arm, For the Gain of independent deformation channels, For the The desired angle of the arm, For the The current angle of the arm.