Experimental method and device for split type hovercar docking test

Abstract

The invention provides a split type hovercar docking test experimental method, which comprises the following steps that: after a whole car system is verified, a passive module shares pose information; the active module plans an initial docking path according to environment docking permission conditions and the pose information; in the precise butt joint area, the motion trail is precisely and locally corrected according to the pose error; and the chassis module, the cabin module and the flight module are controlled to cooperate with each other to complete butt joint. The invention further provides an experimental device for the split type hovercar docking test. The experimental device comprises a test board, an undercarriage, an integrated navigation system, a camera, laser equipment, a controller and a test system. Wherein the test board is provided with a protective fence, and the undercarriage is arranged on the test board; the combined navigation system and the laser range finder are arranged on the chassis module; the camera is installed on the cabin module, and the reflecting plate is installed on the undercarriage. According to the experimental method and device for the butt joint test of the split-type hovercar, the overall butt joint test of the split-type hovercar can be realized, and the control precision is high.

Description

Technical Field

[0001] The invention relates to a testing technology, and in particular to an experimental method and a device for a split-type flying car docking test. Background Art

[0002] The split flying car is an effective means of transportation to solve the problem of large-scale urban traffic congestion. The split flying car consists of a flight module, a cockpit module and a chassis module. The cockpit module and the chassis module can be combined to realize the ground driving function. When the road conditions are congested, the cockpit module can be separated from the chassis module and combined with the flight module to bypass the congested road section and fly to the destination. Since the split flying car has not yet been put into use, there is no relevant technology for the split flying car docking test.

[0003] It can be seen that in the prior art, there is no experimental method and device for docking test of split flying cars. Summary of the invention

[0004] In view of this, the main purpose of the present invention is to provide an experimental method and device for docking test of a split flying car with overall testing, synchronous positioning of each module, and control of precise take-off and landing of the flying module.

[0005] In order to achieve the above object, the first technical solution proposed by the present invention is:

[0006] An experimental method for a split-type flying car docking test comprises the following steps:

[0007] Step 1: At the beginning of the docking test, the split flying car first completes the system verification of the whole vehicle by itself to ensure its normal operation.

[0008] Step 2: The split flying car sends its own position information and attitude information to the cockpit module and chassis module as active modules according to the received docking command.

[0009] Step 3: The active module uses its own camera and lidar to obtain information about the surrounding environment.

[0010] Step 4: The chassis module plans an initial docking path according to the docking conditions allowed by the environment, the position information of the active module and the attitude information of the active module; then, it enters the precise docking area within the landing gear range where the passive module is located along the initial docking path.

[0011] Step 5: In the precise docking area, the active module uses its own camera to identify the identification image at the bottom of the passive module to obtain the current position error and attitude error of the active module relative to the passive module, and the active module performs local correction on the initial docking path to obtain a precise docking path.

[0012] Step 6: When the active module approaches the passive module along the precise docking path, the chassis module or the cockpit module adjusts its own position or posture, and the cockpit module is lifted by the chassis module so that the docking points of the cockpit module and the flight module overlap and lock, thus completing the docking process precisely.

[0013] In summary, in the split flying car docking test experimental method described in the invention, the flight module is a passive module, and the chassis module and the cockpit module are active modules. During the docking process, the chassis module carries the cockpit module to find the flight module to complete the docking of the cockpit module and the flight module. At the beginning of the actual test process, the split flying car first completes the whole vehicle system verification. After that, when the split flying car receives the docking instruction, the flight module sends its own position information and attitude information to the cockpit module and the chassis module. The cockpit module and the chassis module also obtain the surrounding environment information through the sensors installed on them. After the chassis module determines that the surrounding environment information meets the environment to allow docking conditions, it plans the initial docking path according to the position information and attitude information of the chassis module and the cockpit module. The chassis module carries the cockpit module along the initial docking path to enter the precise docking area within the landing gear range where the flight module is located. In the precise docking area, the chassis module makes local precise corrections to its own motion trajectory according to the position error and attitude error between the flight module and the chassis module or the cockpit module, and lifts the cockpit module by the chassis module, so that the docking point of the flight module and the cockpit module coincides, and then the docking point is locked, thus completing the docking process of the flight module and the cockpit module. In practical applications, after the flight module and the cockpit module are docked, the flight module carries the cockpit module to the destination. It can be seen that the experimental method for the docking test of a split flying car described in the present invention realizes the overall test of the three modules of the flying car through the synchronous positioning of the three modules, and can accurately control the position and attitude of the three modules, so the present invention also has the characteristics of high control accuracy.

[0014] In order to achieve the above object, the second technical solution proposed by the present invention is:

[0015] An experimental device for split-type flying car docking test, comprising: a test bench for carrying landing gear, a flight module, a cockpit module, a camera, a landing gear for parking the flight module, an integrated navigation system, 4 cameras, 5 sets of laser equipment, a controller, and a test system; wherein each set of laser equipment includes a laser rangefinder and a reflector; the integrated navigation system includes: a global navigation satellite system and an inertial measurement unit; the controller is installed on the chassis module;

[0016] The combined navigation system is used to obtain the three-dimensional acceleration, three-dimensional velocity, three-dimensional angular acceleration, three-dimensional angular velocity, accuracy, and latitude of the cockpit module or chassis module, and record the docking motion trajectory of the cockpit module and the flight module; and send the docking motion trajectory to the test system.

[0017] The camera is used to capture video images of the precise docking process between the cockpit module and the flight module, determine the position, direction and motion trajectory of the chassis module, and send the chassis motion trajectory to the test system.

[0018] The laser rangefinder is used to emit a laser beam to the corresponding reflector and receive the laser beam emitted by the corresponding reflector; the distance between the edge of the chassis module corresponding to the same side of the laser rangefinder on the chassis module and the landing gear on the same side is determined according to the emission time and reception time of the laser beam.

[0019] The reflector is used to reflect the laser beam sent by the laser rangefinder back to the laser rangefinder.

[0020] A control system is used for vehicle system verification; according to the received docking instruction, the position information and attitude information of the flight module sent by the flight module are received; the surrounding environment information is obtained, and the initial docking path is planned according to the docking conditions allowed by the environment, the position information and attitude information of the chassis module or the cockpit module; the chassis module is controlled to carry the cockpit module along the initial docking path to enter the precise docking area within the landing gear range where the flight module is located; in the precise docking area, the identification image at the bottom of the flight module is identified to obtain the current position error and attitude error of the flight module relative to the chassis module, and the initial docking path is partially corrected to obtain the precise docking path, and the precise docking path is sent to the test system; when the active module is controlled to approach the passive module along the precise docking path, the chassis module or the cockpit module adjusts its own position or attitude, and the chassis module is controlled to lift the cockpit module so that the docking points of the cockpit module and the flight module overlap and lock the docking points, and the docking process is completed accurately.

[0021] The test system is used to collect and store the position, posture, precise docking path of the chassis module, chassis motion trajectory, and docking motion trajectory of the chassis module and the cockpit module, and to analyze and replay the precise docking path, chassis motion trajectory, and docking motion trajectory of the active module.

[0022] Guardrails are installed at intervals around the edges of the test bench, and the landing gear is installed on the test bench; the integrated navigation system is installed at the geometric center of the chassis module; the four cameras are respectively installed at the front, rear and two wings of the cockpit module, the camera lens installed at the front is parallel to the vertical plane of the front, the camera lens installed at the rear is parallel to the vertical plane of the rear, and the cameras symmetrically installed on the two wings are located between the corresponding front wheels and rear wheels; two laser rangefinders are installed on one wing of the chassis module, and are respectively located above the front wheel and the rear wheel on that side; two laser rangefinders are installed on the other wing of the chassis module, and are respectively located above the front wheel and the rear wheel on that side; one laser rangefinder is installed at the rear of the chassis module, and is located between the two rear wheels; five reflectors are installed on the landing gear, and correspond one to one to the above-mentioned five laser rangefinders.

[0023] In summary, in the experimental device for docking test of a split flying car described in the invention, the sensor system includes a combined navigation system, a camera, and a laser ranging device: the combined navigation system obtains the position information, attitude information, etc. of the cockpit module and the chassis module, and records the docking trajectory of the cockpit module and the flight module; the camera captures the video image of the precise docking of the cockpit module and the flight module, the position and motion trajectory of the chassis module; the laser ranging device is used to detect the distance between the split flying car and the surrounding landing gear. After completing the vehicle verification and receiving the docking instruction, the control system installed on the chassis module determines whether the surrounding environment meets the docking conditions allowed by the environment according to the above information collected by the sensor system, and plans the initial docking path; controls the active module, that is, the chassis module carries this cabin module, along the initial planned path, and enters the precise docking area within the landing gear range; in the precise docking area, according to the position error and attitude error between the flight module and the active module, the initial docking path is locally and precisely corrected, so that the chassis module, the cockpit module, and the flight module are coordinated with each other, the docking points overlap and are locked, and the precise docking process is completed. In addition, the test system also analyzes the above-mentioned information collected, and can also replay the precise docking trajectory and chassis motion trajectory, etc., and can also objectively evaluate the precise docking process based on the above-mentioned information. It can be seen that the experimental device for the split flying car docking test of the present invention can complete the overall test of the three modules of the flying car, and can realize the synchronous positioning of the three modules and the precise control of the path trajectory and docking trajectory. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The figure is a schematic diagram of the overall process of a split-type flying car docking test experimental method described in the present invention.

[0025] Figure 2 The figure is a schematic diagram of the overall motion trajectory of a split-type flying car in a horizontal state in the initial relative position in a docking test experiment described in the present invention.

[0026] Figure 3 The figure is a schematic diagram of the overall motion trajectory of a split-type flying car in a vertical state in the initial relative position in a docking test experiment described in the present invention.

[0027] Figure 4 This is a distribution diagram of the sensor system in the split-type flying car docking test experimental device described in the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] Figure 1 The figure is a schematic diagram of the overall process of the split-type flying car docking test experimental method described in the present invention. Figure 1 As shown, the experimental method for docking test of a split flying car described in the present invention comprises the following steps:

[0030] Step 1: At the beginning of the docking test, the split flying car first completes the system verification of the whole vehicle by itself to ensure its normal operation.

[0031] Step 2: The split flying car sends its own position information and attitude information to the cockpit module and chassis module as active modules according to the received docking command.

[0032] In practical applications, the flight module is equipped with a GPS system. In the present invention, the location information of the flight module includes: the accuracy of the flight module and the latitude of the flight module; the attitude information of the flight module includes: the three-dimensional acceleration, three-dimensional velocity, three-dimensional angular acceleration, and three-dimensional angular velocity of the flight module. The "three directions" here refer to the horizontal and longitudinal directions of the horizontal plane and the vertical direction perpendicular to the horizontal plane.

[0033] Step 3: The active module uses its own camera and lidar to obtain information about the surrounding environment.

[0034] Step 4: The chassis module plans an initial docking path according to the docking conditions allowed by the environment, the position information of the active module and the attitude information of the active module; then, it enters the precise docking area within the landing gear range where the passive module is located along the initial docking path.

[0035] Figure 2 The figure is a schematic diagram of the overall motion trajectory of a split-type flying car in a horizontal state in the initial relative position in a docking test experiment described in the present invention. Figure 3 The figure is a schematic diagram of the overall motion trajectory of a split flying car in a docking test experiment of the present invention in a vertical state of the initial relative position. Figure 2 , Figure 3As shown, when the initial relative position in the split flying car docking test experiment is horizontal and when the initial relative position in the split flying car docking test experiment is vertical, the split flying car enters the precise docking area within the landing gear range along the initial docking path.

[0036] Step 5: In the precise docking area, the active module uses its own camera to identify the identification image at the bottom of the passive module to obtain the current position error and attitude error of the active module relative to the passive module, and the active module performs local correction on the initial docking path to obtain a precise docking path.

[0037] In step 5 of the present invention, the active module performs local correction on the initial docking path, specifically: the chassis module uses longitudinal error control and lateral error control to perform local precise planning of the initial docking trajectory. Here, the longitudinal error refers to the error of the chassis along the direction of the initial planning path, and the lateral error refers to the error of the chassis in the direction perpendicular to the initial planning path when it moves along the initial planning path.

[0038] Step 6: When the active module approaches the passive module along the precise docking path, the chassis module or the cockpit module adjusts its own position or posture, and the cockpit module is lifted by the chassis module so that the docking points of the cockpit module and the flight module overlap and lock, thus completing the docking process precisely.

[0039] In step 6 of the present invention, the active module approaches the passive module along the precise docking path, specifically: the cockpit module approaches the flight module in the parked state along the precise docking path under the drive of the chassis module.

[0040] In practical applications, the experimental method for docking test of a split-type flying car further includes step 7: objectively evaluating the precise docking of the cockpit module and the flight module.

[0041] In step 7 of the present invention, the objective evaluation includes: docking success rate, chassis module positioning success rate, chassis module positioning success time, kneading times, cockpit module and flight module docking time, cockpit module and flight module docking average speed, chassis module lifting cockpit module speed, chassis module lifting cockpit module time, specifically as follows:

[0042] Connection success rate Among them, m1 represents the number of successful dockings between the cockpit module and the flight module, and n1 represents the number of docking commands issued.

[0043] Chassis module positioning success rate Among them, m2 represents the number of successful positioning of the chassis module, and n2 represents the total number of positioning times.

[0044] The number of times the chassis module switches from forward gear to reverse gear or from reverse gear to forward gear when the cockpit module is docked with the flight module.

[0045] Time required for chassis module to be successfully positioned t d =t2-t d1 ; Among them, t2 represents the time when the docking instruction is issued, t d1 The moment when the chassis module is successfully positioned.

[0046] The time taken for the cockpit module to dock with the flight module q =t2-t q1 ; where t q1 Indicates the moment when the cockpit module and the flight module are docked.

[0047] Average docking speed of cockpit module and flight module Where θ represents the number of docking speed samples from the time the docking command is issued to the time the cockpit module and the flight module are docked, v r represents the docking velocity of the rth sampling point; θ is a positive integer, r is a non-negative integer, and r = 0, 1, …, θ.

[0048] The time taken for the chassis module to lift the cockpit module is t j =t j2 -t j1 ; where t j2 Indicates the moment when the chassis module starts to lift, t j1 Indicates the moment when the cockpit module and the flight module are docked.

[0049] In summary, in the split flying car docking test experimental method described in the invention, the flight module is a passive module, and the chassis module and the cockpit module are active modules. During the docking process, the chassis module carries the cockpit module to find the flight module to complete the docking of the cockpit module and the flight module. At the beginning of the actual test process, the split flying car first completes the vehicle system verification. After that, when the split flying car receives the docking instruction, the flight module sends its own position information and attitude information to the cockpit module and the chassis module. The cockpit module and the chassis module also obtain the surrounding environment information through the sensors installed on them. After the chassis module determines that the surrounding environment information meets the environment to allow docking conditions, it plans the initial docking path according to the position information and attitude information of the chassis module and the cockpit module. The chassis module carries the cockpit module along the initial docking path to enter the precise docking area within the landing gear range where the flight module is located. In the precise docking area, the chassis module makes local precise corrections to its own motion trajectory according to the position error and attitude error between the flight module and the chassis module or the cockpit module, and lifts the cockpit module by the chassis module, so that the docking point of the flight module and the cockpit module coincides, and then the docking point is locked, thus completing the docking process of the flight module and the cockpit module. In practical applications, after the flight module and the cockpit module are docked, the flight module carries the cockpit module to the destination. It can be seen that the experimental method for the docking test of a split flying car described in the present invention realizes the overall test of the three modules of the flying car through the synchronous positioning of the three modules, and can accurately control the position and attitude of the three modules, so the present invention also has the characteristics of high control accuracy.

[0050] In step 3 of the present invention, the environment allows docking conditions to be specifically:

[0051] Environment allows docking = (W <W max )∧(V>V min )∧(S>S min )∧O∧P;

[0052] Where W represents wind speed, W max represents the maximum permissible wind speed; V represents visibility, V min represents the minimum required visibility; S represents the landing gear size, S min Indicates the minimum allowable landing gear size; O indicates obstacle information; P indicates path information.

[0053] In the present invention, the obstacle information O is the horizontal distance d between the ith obstacle and the split flying car. i ; The absence of obstacles on the initial docking path is represented by: d i >d safe ; where d safe Represents the safety distance, and i is a natural number.

[0054] In the present invention, the path information P includes: the width W of the initial docking path path , the length of the initial docking path L path , Width of landing gear W gear , the length of the landing gear is L gear ; and the path information P satisfies: the width of the initial docking path should be less than the width of the landing gear minus the safety margin:

[0055] W path <W gear -W safe

[0056] The length of the initial docking path should be less than the length of the landing gear plus a safety margin:

[0057] L path <L gear -L safe

[0058] Among them, W safe Indicates the width safety margin of the initial docking path, L safe Indicates the length safety margin of the initial docking path.

[0059] In the present invention, the longitudinal error control adopts a dual proportional integral differential (PID) control method, and the dual PID control method includes the following steps:

[0060] Step A1: Obtain the actual position p of the chassis module on the initial docking path s (t), and according to the planned position p of the chassis module on the initial docking path c (t), and obtain the position deviation e of the chassis module on the initial docking path p (t) = p c (t)-p s (t), and the position deviation e p (t) Perform the following outer loop PID control to obtain the speed difference compensation h v (t):

[0061]

[0062] Among them, K p1 is the position proportional coefficient, K i1 is the position integral coefficient, K d1 is the position differential coefficient; t is the time.

[0063] Step A2: Obtain the actual longitudinal speed v of the chassis module on the initial docking path s (t), and according to the planned longitudinal speed v of the chassis module on the initial docking pathc (t) and the speed difference compensation h obtained in step A1 v (t), and obtain the speed deviation e of the chassis module on the initial docking path v (t) = v c (t)+h v (t)-v s (t), and the speed deviation e v (t) Perform the following inner loop PID control to obtain the acceleration difference compensation h a (t):

[0064]

[0065] Among them, K p2 is the speed proportional coefficient, K i2 is the speed integral coefficient, K d2 is the velocity differential coefficient.

[0066] Step A3: According to the planned acceleration a of the chassis module on the initial docking path c (t), the acceleration difference compensation h obtained in step A2 a (t), and obtain the actual acceleration a of the chassis module on the initial docking path s (t) = a c (t)+h a (t).

[0067] Step A4: the actual acceleration a obtained in step A3 s (t), perform torque control of the chassis module to obtain the driving torque or braking torque of the chassis module.

[0068] In the present invention, the lateral error control adopts a model predictive control (MPC) method, and the MPC control method specifically includes the following steps:

[0069] Step B1: construct a nonlinear kinematic discretization state space model for the chassis module, as follows:

[0070]

[0071] Among them, the state variable matrix y(k) is the lateral position of the chassis module at time k, is the derivative of the lateral position of the chassis module at time k, is the yaw angle of the chassis module at time k, is the derivative of the yaw angle of the chassis module at time k, T represents the matrix transpose; the control increment at time k Δu(k)=u(k)-u(k-1); ω(k) represents the disturbance; k is an integer; the state variable augmentation coefficient Control variable augmentation coefficient Interference enhancement factor They are as follows:

[0072]

[0073] Here, A represents the conventional coefficient of state variables, B represents the conventional coefficient of control variables, and C represents the conventional coefficient of interference; I represents the 1 matrix, The "0" in represents the 0 matrix; and,

[0074]

[0075] Among them, the initial coefficient of state variable A0, the initial coefficient of control variable B0, and the initial coefficient of interference C0 are as follows:

[0076]

[0077] Where m represents the total mass of the chassis module and the cockpit module, I z represents the moment of inertia of the chassis module, a represents the distance from the front axle of the chassis module to the center of mass, b represents the distance from the rear axle of the chassis module to the center of mass, C f is the sum of the front wheel cornering stiffness of the chassis module, C r is the sum of the stiffness of the rear wheel side panels of the chassis module; δ represents the sampling time.

[0078] Step B2: According to the state variable matrix prediction value obtained in step B1, the following objective function J(k) is established:

[0079]

[0080] Among them, X ref (k) represents the reference value of the state variable matrix at time k, N c represents the control time domain, N p represents the prediction time domain, Q represents the weight matrix of the state variable error, R represents the weight matrix of the control increment, ρ represents the relaxation factor weight, ε represents the relaxation factor; ||·|| represents the modulus; j is a natural number, and j=1,2,…,,; l is a non-negative integer, and l=0,1,2,…,N c -1.

[0081] Step B3: According to the objective function J(k), the optimal control quantity sequence in the prediction time domain is obtained through rolling optimization solution. And return the first element in the sequence to step B1.

[0082] Step B4: sending Δu(k)+u(k-1) as a wheel angle command to the electric power steering system of the chassis module. The electric power steering system executes the angle command to achieve lateral control of the chassis module.

[0083] In the present invention, the steering angle increment Δu as the control increment is constrained to satisfy: Δu min ≤Δu(k+l)≤Δu max ; where Δu(k) is the discretization of Δu(t); Δu max , Δu min are the maximum and minimum values ​​of the steering angle increment respectively.

[0084] In the present invention, the sideslip angle β of the center of mass of the chassis module satisfies: in, β are the maximum and minimum values ​​of the center of mass side slip angle of the chassis module, μ r is the road adhesion coefficient of the chassis module, g is the acceleration of gravity,

[0085] In the present invention, the yaw angular velocity γ of the chassis module satisfies: in, γ are the maximum and minimum values ​​of the yaw angular velocity, respectively.

[0086] An experimental device for split-type flying car docking test, comprising: a test bench 1 for carrying a landing gear 3, a flight module, a cockpit module, and a camera 5, a landing gear 3 for parking the flight module, a combined navigation system 4, four cameras 5, five groups of laser equipment 6, a controller, and a test system; wherein each group of laser equipment 6 comprises a laser rangefinder 61 and a reflector 62; the combined navigation system 4 comprises: a global navigation satellite system (GNSS, Global Navigation Satellite System), an inertial measurement unit (IMU, Inertial Measurement Unit); the controller is installed on the chassis module;

[0087] The integrated navigation system 4 is used to obtain the three-dimensional acceleration, three-dimensional velocity, three-dimensional angular acceleration, three-dimensional angular velocity, accuracy, and latitude of the cockpit module or the chassis module, and record the docking motion trajectory of the cockpit module and the flight module; and send the docking motion trajectory to the test system.

[0088] Camera 5 is used to capture video images of the precise docking process between the cockpit module and the flight module, determine the position, direction and motion trajectory of the chassis module, and send the chassis motion trajectory to the test system.

[0089] The laser rangefinder 61 is used to emit a laser beam to the corresponding reflector 62 and receive the laser beam emitted back by the corresponding reflector 62; the distance between the edge of the chassis module corresponding to the same side of the laser rangefinder 61 on the chassis module and the landing gear 3 on the same side is determined according to the laser beam emission time and reception time.

[0090] The reflector 62 is used to reflect the laser beam sent by the laser rangefinder 61 back to the laser rangefinder.

[0091] A control system is used for vehicle system verification; according to the received docking instruction, the position information and attitude information of the flight module sent by the flight module are received; the surrounding environment information is obtained, and the initial docking path is planned according to the docking conditions allowed by the environment, the position information and attitude information of the chassis module or the cockpit module; the chassis module is controlled to carry the cockpit module along the initial docking path to enter the precise docking area within the landing gear range where the flight module is located; in the precise docking area, the identification image at the bottom of the flight module is identified to obtain the current position error and attitude error of the flight module relative to the chassis module, and the initial docking path is partially corrected to obtain the precise docking path, and the precise docking path is sent to the test system; when the active module is controlled to approach the passive module along the precise docking path, the chassis module or the cockpit module adjusts its own position or attitude, and the chassis module is controlled to lift the cockpit module so that the docking points of the cockpit module and the flight module overlap and lock the docking points, and the docking process is completed accurately.

[0092] The test system is used to collect and store the position, posture, precise docking path of the chassis module, chassis motion trajectory, and docking motion trajectory of the chassis module and the cockpit module, and to analyze and replay the precise docking path, chassis motion trajectory, and docking motion trajectory of the active module.

[0093] Guardrails 2 are installed at intervals on the edges of the test bench 1, and the landing gear is installed on the test bench 1; the integrated navigation system 4 is installed at the geometric center of the chassis module. Figure 4 This is a distribution diagram of the sensor system in the split-type flying car docking test experimental device of the present invention. Figure 4 As shown, four cameras 5 are respectively installed at the front, rear and two wings of the cockpit module, the camera lens installed at the front is parallel to the vertical plane of the front, the camera lens installed at the rear is parallel to the vertical plane of the rear, and the cameras symmetrically installed at the two wings are located between the corresponding front wheels and rear wheels; two laser rangefinders 61 are installed on one wing of the chassis module, and are respectively located above the front wheel and the rear wheel on that side; two laser rangefinders 61 are installed on the other wing of the chassis module, and are respectively located above the front wheel and the rear wheel on that side; one laser rangefinder 61 is installed at the rear of the chassis module, and is located between the two rear wheels; five reflectors 62 are installed on the landing gear, and correspond one to one with the above-mentioned five laser rangefinders 61.

[0094] In actual application, the dimensions of the test bench 1 are: 15 meters long and 12 meters wide. The test bench 1 has a load-bearing capacity of 2,000 kilograms, adopts a steel structure frame, and is equipped with four support columns and two beams. The test bench 1 is suitable for various types of split flying cars and can ensure the safe and reliable testing process. In addition, the guardrails around the test bench can protect the safety of the split flying car and the testers: the minimum height of the guardrail cannot be lower than the height of the chassis module of the split flying car being tested, and the maximum spacing between the guardrails cannot exceed the passable width of the split flying car being tested.

[0095] In practical applications, the sensor system in the experimental device of the present invention includes: a combined navigation system 4, four cameras 5, and five groups of laser equipment 6.

[0096] In summary, in the experimental device for the split flying car docking test described in the present invention, the sensor system includes a combined navigation system, a camera, and a laser ranging device: the combined navigation system obtains the position information, attitude information, etc. of the cockpit module and the chassis module, and records the docking trajectory of the cockpit module and the flight module; the camera captures the video image of the precise docking of the cockpit module and the flight module, the position and motion trajectory of the chassis module; the laser ranging device is used to detect the distance between the split flying car and the surrounding landing gear. After completing the vehicle verification and receiving the docking instruction, the control system installed on the chassis module determines whether the surrounding environment meets the docking conditions allowed by the environment according to the above information collected by the sensor system, and plans the initial docking path; controls the active module, that is, the chassis module carries this cabin module, along the initial planned path, and enters the precise docking area within the landing gear range; in the precise docking area, according to the position error and attitude error between the flight module and the active module, the initial docking path is locally and accurately corrected, so that the chassis module, the cockpit module, and the flight module are coordinated with each other, the docking points overlap and are locked, and the precise docking process is completed. In addition, the test system also analyzes the above-mentioned information collected, and can also replay the precise docking trajectory and chassis motion trajectory, etc., and can also objectively evaluate the precise docking process based on the above-mentioned information. It can be seen that the experimental device for the split flying car docking test of the present invention can complete the overall test of the three modules of the flying car, and can realize the synchronous positioning of the three modules and the precise control of the path trajectory and docking trajectory.

[0097] In practical applications, the test system is also used to objectively evaluate the precise docking between the cockpit module and the flight module during analysis and playback.

[0098] In the test system of the present invention, the objective evaluation includes: docking success rate, chassis module positioning success rate, time required for chassis module positioning success, number of rubbing times, time taken for the cockpit module to dock with the flight module, average speed of the cockpit module to dock with the flight module, speed of the chassis module lifting the cockpit module, and time taken for the chassis module to lift the cockpit module, as follows:

[0099] Connection success rate Among them, m1 represents the number of successful dockings between the cockpit module and the flight module, and n1 represents the number of docking commands issued.

[0100] Chassis module positioning success rate Among them, m2 represents the number of successful positioning of the chassis module, and n2 represents the total number of positioning times.

[0101] The number of times the chassis module switches from forward gear to reverse gear or from reverse gear to forward gear when the cockpit module is docked with the flight module.

[0102] Time required for chassis module to be successfully positioned t d =t2-t d1 ; Among them, t2 represents the time when the docking instruction is issued, t d1 The moment when the chassis module is successfully positioned.

[0103] The time taken for the cockpit module to dock with the flight module q =t2-t q1 ; where t q1 Indicates the moment when the cockpit module and the flight module are docked.

[0104] Average docking speed of cockpit module and flight module Where θ represents the number of docking speed samples from the time the docking command is issued to the time the cockpit module and the flight module are docked, v r represents the docking velocity of the rth sampling point; θ is a positive integer, r is a non-negative integer, and r = 0, 1, …, θ.

[0105] The time taken for the chassis module to lift the cockpit module is t j =t j2 -t j1 ; where t j2 Indicates the moment when the chassis module starts to lift, t j1 Indicates the moment when the cockpit module and the flight module are docked.

[0106] In the device of the present invention, the environment allows docking conditions specifically as follows:

[0107] Environment allows docking = (W <W max )∧(V>V min )∧(S>S min )∧O∧P;

[0108] Where W represents wind speed, W max represents the maximum permissible wind speed; V represents visibility, V min represents the minimum required visibility; S represents the landing gear size, S min Indicates the minimum allowable landing gear size; O indicates obstacle information; P indicates path information.

[0109] In the device of the present invention, the obstacle information O is the horizontal distance d between the ith obstacle and the split flying car. i ; The absence of obstacles on the initial docking path is represented by: d i >d safe ; where d safe Represents the safety distance, i is a natural number,

[0110] In the device of the present invention, the path information P includes: the width W of the initial docking path path , the length of the initial docking path L path , Width of landing gear W gear , the length of the landing gear is L gear ; and the path information P satisfies: the width of the initial docking path should be less than the width of the landing gear minus the safety margin:

[0111] W path <W gear -W safe ;

[0112] The length of the initial docking path should be less than the length of the landing gear plus a safety margin:

[0113] L path <L gear -L safe ;

[0114] Among them, W safe Indicates the width safety margin of the initial docking path, L safe Indicates the length safety margin of the initial docking path.

[0115] In the device of the present invention, the active module partially corrects the initial docking path, specifically: the control system uses longitudinal error control and lateral error control to perform local precision planning of the initial docking trajectory. The active module approaches the passive module along the precise docking path, specifically: the cockpit module approaches the flight module in the parked state along the precise docking path under the drive of the control system.

[0116] In the device of the present invention, the longitudinal error control adopts a dual proportional integral differential control method, including the following steps:

[0117] Step A1: Obtain the actual position p of the chassis module on the initial docking path s (t), and according to the planned position p of the chassis module on the initial docking path c (t), and obtain the position deviation e of the chassis module on the initial docking path p (t) = p c (t)-p s (t), and the position deviation e p (t) Perform the following outer loop PID control to obtain the speed difference compensation h v (t):

[0118]

[0119] Among them, K p1 is the position proportional coefficient, K i1 is the position integral coefficient, K d1 is the position differential coefficient; t is the time.

[0120] Step A2: Obtain the actual longitudinal speed v of the chassis module on the initial docking path s (t), and according to the planned longitudinal speed v of the chassis module on the initial docking path c (t) and the speed difference compensation h obtained in step A1 v (t), and obtain the speed deviation e of the chassis module on the initial docking path v (t) = v c (t)+h v (t)-v s (t), and the speed deviation e v (t) Perform the following inner loop PID control to obtain the acceleration difference compensation h a (t):

[0121]

[0122] Among them, K p2 is the speed proportional coefficient, K i2 is the speed integral coefficient, K d2 is the velocity differential coefficient.

[0123] Step A3: According to the planned acceleration a of the chassis module on the initial docking path c (t), the acceleration difference compensation h obtained in step A2 a (t), and obtain the actual acceleration a of the chassis module on the initial docking path s (t) = a c (t)+h a (t).

[0124] Step A4: the actual acceleration a obtained in step A3 s (t), perform torque control of the chassis module to obtain the driving torque or braking torque of the chassis module.

[0125] In the device of the present invention, the lateral error control adopts a model predictive control method, which includes the following steps:

[0126] Step B1: construct a nonlinear kinematic discretization state space model for the chassis module, as follows:

[0127]

[0128] Among them, the state variable matrix y(k) is the lateral position of the chassis module at time k, is the derivative of the lateral position of the chassis module at time k, is the yaw angle of the chassis module at time k, is the derivative of the yaw angle of the chassis module at time k, T represents the matrix transpose; the control increment at time k Δu(k)=u(k)-u(k-1); ω(k) represents the disturbance; k is an integer; the state variable augmentation coefficient Control variable augmentation coefficient Interference enhancement factor They are as follows:

[0129]

[0130] Here, A represents the conventional coefficient of state variables, B represents the conventional coefficient of control variables, and C represents the conventional coefficient of interference; I represents the 1 matrix, The "0" in represents the 0 matrix; and,

[0131]

[0132] Among them, the initial coefficient of state variable A0, the initial coefficient of control variable B0, and the initial coefficient of interference C0 are as follows:

[0133]

[0134] Where m represents the total mass of the chassis module and the cockpit module, I z represents the moment of inertia of the chassis module, a represents the distance from the front axle of the chassis module to the center of mass, b represents the distance from the rear axle of the chassis module to the center of mass, C f is the sum of the front wheel cornering stiffness of the chassis module, C r is the sum of the stiffness of the rear wheel side panels of the chassis module; δ represents the sampling time.

[0135] Step B2: According to the state variable matrix prediction value obtained in step B1, the following objective function J(k) is established:

[0136]

[0137] Among them, X ref (k) represents the reference value of the state variable matrix at time k, N c represents the control time domain, N p represents the prediction time domain, Q represents the weight matrix of the state variable error, R represents the weight matrix of the control increment, ρ represents the relaxation factor weight, ε represents the relaxation factor; ||·|| represents the modulus; j is a natural number, and j=1,2,…,,; l is a non-negative integer, and l=0,1,2,…,N c -1.

[0138] Step B3: According to the objective function J(k), the optimal control quantity sequence in the prediction time domain is obtained through rolling optimization solution. And return the first element in the sequence to step B1.

[0139] Step B4: sending Δu(k)+u(k-1) as a wheel angle command to the electric power steering system of the chassis module. The electric power steering system executes the angle command to achieve lateral control of the chassis module.

[0140] In the device of the present invention, the steering angle increment Δu as the control increment is constrained to satisfy: Δu min ≤Δu(k+l)≤Δu max ; where Δu(k) is the discretization of Δu(t); Δu max , Δu min are the maximum and minimum values ​​of the steering angle increment respectively.

[0141] In the device of the present invention, the side slip angle β of the center of mass of the chassis module satisfies: in, β are the maximum and minimum values ​​of the center of mass side slip angle of the chassis module, μ r is the road adhesion coefficient of the chassis module, g is the acceleration of gravity;

[0142] In the device of the present invention, the yaw angular velocity γ of the chassis module satisfies: in, γ are the maximum and minimum values ​​of the yaw angular velocity, respectively.

[0143] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An experimental method for docking test of a split flying car, characterized in that: The experimental method comprises the following steps: Step 1: At the beginning of the docking test, the split flying car first completes the system calibration of the whole vehicle to ensure its normal operation; Step 2: The split flying car sends its own position information and attitude information to the cockpit module and chassis module as active modules according to the received docking command. Step 3: The active module uses its own camera and laser radar to obtain surrounding environment information; Step 4: The chassis module plans an initial docking path according to the docking conditions allowed by the environment, the position information of the active module, and the attitude information of the active module; then, it enters the precise docking area within the landing gear range where the passive module is located along the initial docking path; Step 5: In the precise docking area, the active module uses its own camera to identify the identification image at the bottom of the passive module to obtain the current position error and attitude error of the active module relative to the passive module, and the active module performs a partial correction on the initial docking path to obtain a precise docking path; Step 6: When the active module approaches the passive module along the precise docking path, the chassis module or the cockpit module adjusts its own position or posture, and the cockpit module is lifted by the chassis module so that the docking points of the cockpit module and the flight module overlap and lock, thus completing the docking process precisely.

2. The experimental method for docking test of a split flying car according to claim 1, characterized in that: In step 3, the environment allows docking conditions to be specifically: Environment allows docking = (W <W max )∧(V>V min )∧(S>S min )∧O∧P; Where W represents wind speed, W max represents the maximum permissible wind speed; V represents visibility, V min represents the minimum required visibility; S represents the landing gear size, S min Indicates the minimum allowable landing gear size; O indicates obstacle information; P indicates path information.

3. The experimental method for docking test of a split flying car according to claim 2, characterized in that: The obstacle information O is the horizontal distance d between the ith obstacle and the split flying car. i ; The absence of obstacles on the initial docking path is represented by: d i >d safe ; Among them, d safe Represents the safety distance, i is a natural number; The path information P includes: the width W of the initial docking path path , the length of the initial docking path L path , Width of landing gear W gear , the length of the landing gear is L gear ; and the path information P satisfies: the width of the initial docking path should be less than the width of the landing gear minus the safety margin: IN path <W gear -IN safe The length of the initial docking path should be less than the length of the landing gear plus a safety margin: L path <L gear -L safe Among them, W safe Indicates the width safety margin of the initial docking path, L safe Indicates the length safety margin of the initial docking path.

4. The experimental method for docking test of a split flying car according to claim 1 or 3, characterized in that: In step 5, the active module performs local correction on the initial docking path, specifically: the chassis module uses longitudinal error control and lateral error control to perform local precise planning on the initial docking trajectory; In step 6, the active module approaches the passive module along the precise docking path. Specifically, the cockpit module approaches the flight module in the parked state along the precise docking path under the drive of the chassis module.

5. The experimental method for docking test of a split flying car according to claim 4 is characterized in that: The longitudinal error control adopts a dual PID control method, and the dual PID control method includes the following steps: Step A1: Obtain the actual position p of the chassis module on the initial docking path s (t), and according to the planned position p of the chassis module on the initial docking path c (t), and obtain the position deviation e of the chassis module on the initial docking path p (t) = p c (t)-p s (t), and the position deviation e p (t) Perform the following outer loop PID control to obtain the speed difference compensation h v (t): Among them, K p1 is the position proportional coefficient, K i1 is the position integral coefficient, K d1 is the position differential coefficient; t is the time; Step A2: Obtain the actual longitudinal speed v of the chassis module on the initial docking path s (t), and according to the planned longitudinal speed v of the chassis module on the initial docking path c (t) and the speed difference compensation h obtained in step A1 v (t), and obtain the speed deviation e of the chassis module on the initial docking path v (t) = v c (t)+h v (t)-v d (t), and the speed deviation e v (t) Perform the following inner loop PID control to obtain the acceleration difference compensation h a (t): Among them, K p2 is the speed proportional coefficient, K i2 is the speed integral coefficient, K d2 is the velocity differential coefficient; Step A3: According to the planned acceleration a of the chassis module on the initial docking path c (t), the acceleration difference compensation h obtained in step A2 a (t), and obtain the actual acceleration a of the chassis module on the initial docking path s (t) = a c (t)+h a (t); Step A4: the actual acceleration a obtained in step A3 s (k) Perform torque control on the chassis module to obtain the driving torque or braking torque of the chassis module.

6. The experimental method for docking test of a split flying car according to claim 5, characterized in that: The lateral error control adopts an MPC control method, and the MPC control method specifically includes the following steps: Step B1: construct a nonlinear kinematic discretization state space model for the chassis module, as follows: Among them, the state variable matrix y(k) is the lateral position of the chassis module at time k, is the derivative of the lateral position of the chassis module at time k, is the yaw angle of the chassis module at time k, is the derivative of the yaw angle of the chassis module at time k, T represents the matrix transpose; the control increment at time k Δu(k)=u(k)-u(k-1); ω(k) represents the disturbance; k is an integer; the state variable augmentation coefficient Control variable augmentation coefficient Interference enhancement factor They are as follows: Here, A represents the conventional coefficient of state variables, B represents the conventional coefficient of control variables, and C represents the conventional coefficient of interference; I represents the 1 matrix, The "0" in represents the 0 matrix; and, Among them, the initial coefficient of state variable A0, the initial coefficient of control variable B0, and the initial coefficient of interference C0 are as follows: Where m represents the total mass of the chassis module and the cockpit module, I z represents the moment of inertia of the chassis module, a represents the distance from the front axle of the chassis module to the center of mass, b represents the distance from the rear axle of the chassis module to the center of mass, C f is the sum of the front wheel cornering stiffness of the chassis module, C r is the sum of the stiffness of the rear wheel side panels of the chassis module; δ represents the sampling time; Step B2: According to the state variable matrix prediction value obtained in step B1, the following objective function J(k) is established: Among them, X ref (k) represents the reference value of the state variable matrix at time k, N c represents the control time domain, N p represents the prediction time domain, Q represents the weight matrix of the state variable error, R represents the weight matrix of the control increment, ρ represents the relaxation factor weight, ε represents the relaxation factor; ||·|| represents the modulus; j is a natural number, and j=1,2,…,,; l is a non-negative integer, and l=0,1,2,…,N c -1; Step B3: According to the objective function J(k), the optimal control quantity sequence in the prediction time domain is obtained through rolling optimization solution. And return the first element in the sequence to step B1; Step B4: sending Δu(k)+u(k-1) as a wheel angle command to the electric power steering system of the chassis module. The electric power steering system executes the angle command to achieve lateral control of the chassis module.

7. The experimental method for docking test of a split flying car according to claim 6, characterized in that: The steering angle increment Δu as the control increment is constrained to satisfy: Δu min ≤Δu(k+l)≤Δu max ; where Δu(k) is the discretization of Δu(t); Δu max , Δu min are the maximum and minimum values ​​of the steering angle increment respectively; The sideslip angle β of the center of mass of the chassis module satisfies: in, β are the maximum and minimum values ​​of the sideslip angle of the center of mass of the chassis module, μ r is the road adhesion coefficient of the chassis module, g is the acceleration of gravity; The yaw rate γ of the chassis module satisfies: in, γ are the maximum and minimum values ​​of the yaw angular velocity, respectively.

8. The experimental method for docking test of a split flying car according to claim 1 or 6, characterized in that: The experimental method also includes the following steps: Step 7: Objectively evaluate the precise docking between the cockpit module and the flight module.

9. The experimental method for docking test of a split flying car according to claim 8, characterized in that: In step 7, the objective evaluation includes: docking success rate, chassis module positioning success rate, chassis module positioning success time, number of rubbing times, cockpit module and flight module docking time, cockpit module and flight module docking average speed, chassis module lifting cockpit module speed, chassis module lifting cockpit module time, as follows: Connection success rate Among them, m1 represents the number of successful dockings between the cockpit module and the flight module, and n1 represents the number of docking commands issued; Chassis module positioning success rate Among them, m2 represents the number of successful positioning of the chassis module, and n2 represents the total number of positioning times; The number of times of rubbing the warehouse is the number of times the chassis module switches from forward gear to reverse gear or from reverse gear to forward gear when the cockpit module and the flight module are docked; Time required for chassis module to be successfully positioned t d =t2-t d1 ; Among them, t2 represents the time when the docking instruction is issued, t d1 The moment when the chassis module is successfully positioned; The time taken for the cockpit module to dock with the flight module q =t2-t q1 ; where t q1 Indicates the moment when the cockpit module and the flight module are docked; Average docking speed of cockpit module and flight module Where θ represents the number of docking speed samples from the time the docking command is issued to the time the cockpit module and the flight module are docked, v r represents the docking speed of the rth sampling point; θ is a positive integer, r is a non-negative integer, and r = 0, 1, ..., θ; The time taken for the chassis module to lift the cockpit module is t j =t j2 -t j1 ; where t j2 Indicates the moment when the chassis module starts to lift, t j1 Indicates the moment when the cockpit module and the flight module are docked.

10. An experimental device for split-type flying car docking test, characterized in that: The experimental device includes: a test bench for carrying landing gear, flight module, cockpit module, and camera, a landing gear for parking the flight module, an integrated navigation system, 4 cameras, 5 sets of laser equipment, a controller, and a test system; wherein each set of laser equipment includes a laser rangefinder and a reflector; the integrated navigation system includes: a global navigation satellite system and an inertial measurement unit; the controller is installed on the chassis module; The integrated navigation system is used to obtain the three-dimensional acceleration, three-dimensional velocity, three-dimensional angular acceleration, three-dimensional angular velocity, accuracy, and latitude of the cockpit module or chassis module, and record the docking motion trajectory of the cockpit module and the flight module; and send the docking motion trajectory to the test system; The camera is used to capture video images of the precise docking process between the cockpit module and the flight module, determine the position, direction and motion trajectory of the chassis module, and send the chassis motion trajectory to the test system; A laser rangefinder is used to emit a laser beam to a corresponding reflector and receive a laser beam emitted back by the corresponding reflector; and to determine the distance between the edge of the chassis module corresponding to the same side of the laser rangefinder on the chassis module and the landing gear on the same side according to the emission time and the reception time of the laser beam; A reflector, used for reflecting the laser beam sent by the laser rangefinder back to the laser rangefinder; A control system is used for vehicle system verification; according to the received docking instruction, the position information and attitude information of the flight module sent by the flight module are received; the surrounding environment information is obtained, and the initial docking path is planned according to the docking conditions allowed by the environment, the position information and attitude information of the chassis module or the cockpit module; the chassis module is controlled to carry the cockpit module along the initial docking path to enter the precise docking area within the landing gear range where the flight module is located; in the precise docking area, the identification image at the bottom of the flight module is identified to obtain the current position error and attitude error of the flight module relative to the chassis module, and the initial docking path is partially corrected to obtain the precise docking path, and the precise docking path is sent to the test system; when the active module is controlled to approach the passive module along the precise docking path, the chassis module or the cockpit module adjusts its own position or attitude, and the chassis module is controlled to lift the cockpit module so that the docking points of the cockpit module and the flight module overlap and lock the docking points, and the docking process is completed accurately; The test system is used to collect and store the position and posture of the chassis module and the cockpit module, the precise docking path of the chassis module, the chassis motion trajectory, and the docking motion trajectory, and to analyze and replay the precise docking path, chassis motion trajectory, and docking motion trajectory of the active module; Guardrails are installed at intervals around the edges of the test bench, and the landing gear is installed on the test bench; the integrated navigation system is installed at the geometric center of the chassis module; the four cameras are respectively installed at the front, rear and two wings of the cockpit module, the camera lens installed at the front is parallel to the vertical plane of the front, the camera lens installed at the rear is parallel to the vertical plane of the rear, and the cameras symmetrically installed on the two wings are located between the corresponding front wheels and rear wheels; two laser rangefinders are installed on one wing of the chassis module, and are respectively located above the front wheel and the rear wheel on that side; two laser rangefinders are installed on the other wing of the chassis module, and are respectively located above the front wheel and the rear wheel on that side; one laser rangefinder is installed at the rear of the chassis module, and is located between the two rear wheels; five reflectors are installed on the landing gear, and correspond one to one to the above-mentioned five laser rangefinders.

11. The experimental device for split-type flying car docking test according to claim 10, characterized in that: The environment allows docking conditions to be specifically as follows: Environment allows docking = (W <W max )∧(V>V min )∧(S>S min )∧O∧P; where W represents the wind speed, W max represents the maximum permissible wind speed; C represents visibility, V represents min represents the minimum required visibility; S represents the landing gear size, S min Indicates the minimum allowable landing gear size; O indicates obstacle information; P indicates path information.

12. The experimental device for docking test of a split flying car according to claim 11, characterized in that: The obstacle information O is the horizontal distance d between the ith obstacle and the split flying car. i ; The absence of obstacles on the initial docking path is represented by: d i >d safe ; Among them, d safe Represents the safety distance, i is a natural number; The path information P includes: the width W of the initial docking path path , the length of the initial docking path L path , Width of landing gear W gear , the length of the landing gear is L gear ; and the path information P satisfies: the width of the initial docking path should be less than the width of the landing gear minus the safety margin: IN path <W gear -IN safe The length of the initial docking path should be less than the length of the landing gear plus a safety margin: L path <L gear -L safe Among them, W safe Indicates the width safety margin of the initial docking path, L safe Indicates the length safety margin of the initial docking path.

13. The experimental device for split-type flying car docking test according to claim 10 or 12, characterized in that: The active module performs local correction on the initial docking path, specifically: the control system uses longitudinal error control and lateral error control to perform local precise planning on the initial docking trajectory; The active module approaches the passive module along the precise docking path. Specifically, the cockpit module approaches the flight module in the parked state along the precise docking path under the drive of the control system.

14. The experimental device for split-type flying car docking test according to claim 13, characterized in that: The longitudinal error control adopts a dual PID control method, including the following steps: Step A1: Obtain the actual position p of the chassis module on the initial docking path s (t), and according to the planned position p of the chassis module on the initial docking path c (t), and obtain the position deviation e of the chassis module on the initial docking path p (t) = p c (t)-p s (t), and the position deviation e p (t) Perform the following outer loop PID control to obtain the speed difference compensation h v (t): Among them, K p1 is the position proportional coefficient, K i1 is the position integral coefficient, K d1 is the position differential coefficient; t is the time; Step A2: Obtain the actual longitudinal speed v of the chassis module on the initial docking path s (t), and according to the planned longitudinal speed v of the chassis module on the initial docking path c (t) and the speed difference compensation h obtained in step A1 v (t), and obtain the speed deviation e of the chassis module on the initial docking path v (t) = v c (t)+h v (t)-v s (t), and the speed deviation e v (t) Perform the following inner loop PID control to obtain the acceleration difference compensation h a (t): Among them, K p2 is the speed proportional coefficient, K i2 is the speed integral coefficient, K d2 is the velocity differential coefficient; Step A3: According to the planned acceleration a of the chassis module on the initial docking path c (t), the acceleration difference compensation h obtained in step A2 a (t), and obtain the actual acceleration a of the chassis module on the initial docking path s (t) = a c (t)+h a (t); Step A4: the actual acceleration a obtained in step A3 s (t), perform torque control of the chassis module to obtain the driving torque or braking torque of the chassis module.

15. The experimental device for split-type flying car docking test according to claim 14, characterized in that: The lateral error control adopts the MPC control method, including the following steps: Step B1: construct a nonlinear kinematic discretization state space model for the chassis module, as follows: Among them, the state variable matrix y(k) is the lateral position of the chassis module at time k, is the derivative of the lateral position of the chassis module at time k, is the yaw angle of the chassis module at time k, is the derivative of the yaw angle of the chassis module at time k, T represents the matrix transpose; the control increment at time k Δu(k)=u(k)-u(k-1); ω(k) represents the disturbance; k is an integer; the state variable augmentation coefficient Control variable augmentation coefficient Interference enhancement factor They are as follows: Here, A represents the conventional coefficient of state variables, B represents the conventional coefficient of control variables, and C represents the conventional coefficient of interference; I represents the 1 matrix, The "0" in represents the 0 matrix; and, Among them, the initial coefficient of state variable A0, the initial coefficient of control variable B0, and the initial coefficient of interference C0 are as follows: Where m represents the total mass of the chassis module and the cockpit module, I z represents the moment of inertia of the chassis module, a represents the distance from the front axle of the chassis module to the center of mass, b represents the distance from the rear axle of the chassis module to the center of mass, C f is the sum of the front wheel cornering stiffness of the chassis module, C r is the sum of the stiffness of the rear wheel side panels of the chassis module; δ represents the sampling time; Step B2: According to the state variable matrix prediction value obtained in step B1, the following objective function J(k) is established: Among them, X ref (k) represents the reference value of the state variable matrix at time k, N c represents the control time domain, N p represents the prediction time domain, Q represents the weight matrix of the state variable error, R represents the weight matrix of the control increment, ρ represents the relaxation factor weight, ε represents the relaxation factor; ||·|| represents the modulus; j is a natural number, and j=1,2,…,,; l is a non-negative integer, and l=0,1,2,…,N c -1; Step B3: According to the objective function J(k), the optimal control quantity sequence in the prediction time domain is obtained through rolling optimization solution. And return the first element in the sequence to step B1; Step B4: sending Δu(k)+u(k-1) as a wheel angle command to the electric power steering system of the chassis module. The electric power steering system executes the angle command to achieve lateral control of the chassis module.

16. The experimental device for split-type flying car docking test according to claim 15, characterized in that: The steering angle increment Δu as the control increment is constrained to satisfy: Δu min ≤Δu(k+l)≤Δu max ; where Δu(k) is the discretization of Δu(t); Δu max , Δu min are the maximum and minimum values ​​of the steering angle increment respectively; The sideslip angle β of the center of mass of the chassis module satisfies: in, β are the maximum and minimum values ​​of the sideslip angle of the center of mass of the chassis module, μ r is the road adhesion coefficient of the chassis module, g is the acceleration of gravity; The yaw rate γ of the chassis module satisfies: in, γ are the maximum and minimum values ​​of the yaw angular velocity, respectively.

17. The experimental device for split-type flying car docking test according to claim 10 or 16, characterized in that: The test system is also used to objectively evaluate the precise docking of the cockpit module and the flight module during the analysis and playback process.

18. The experimental device for split-type flying car docking test according to claim 17, characterized in that: The objective evaluation includes: docking success rate, chassis module positioning success rate, chassis module positioning success time, number of rubbing times, cockpit module and flight module docking time, cockpit module and flight module docking average speed, chassis module lifting cockpit module speed, chassis module lifting cockpit module time, as follows: Connection success rate Among them, m1 represents the number of successful dockings between the cockpit module and the flight module, and n1 represents the number of docking commands issued; Chassis module positioning success rate Among them, m2 represents the number of successful positioning of the chassis module, and n2 represents the total number of positioning times; The number of times of rubbing the warehouse is the number of times the chassis module switches from forward gear to reverse gear or from reverse gear to forward gear when the cockpit module and the flight module are docked; Time required for chassis module to be successfully positioned t d =t2-t d1 ; Among them, t2 represents the time when the docking instruction is issued, t d1 The moment when the chassis module is successfully positioned; The time taken for the cockpit module to dock with the flight module q =t2-t q1 ; where t q1 Indicates the moment when the cockpit module and the flight module are docked; Average docking speed of cockpit module and flight module Where θ represents the number of docking speed samples from the time the docking command is issued to the time the cockpit module and the flight module are docked, v r represents the docking speed of the rth sampling point; θ is a positive integer, r is a non-negative integer, and r = 0, 1, ..., θ; The time taken for the chassis module to lift the cockpit module is t j =t j2 -t j1 ; where t j2 Indicates the moment when the chassis module starts to lift, t j1 Indicates the moment when the cockpit module and the flight module are docked.

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