Transplanter and levelling method and device thereof based on sliding mode variable structure active disturbance rejection control

Abstract

A transplanting machine and a leveling method and device thereof based on a variable sliding surface active disturbance rejection control, the transplanting machine comprising a leveling device and adopting the following leveling method for lateral leveling; a three-dimensional model of the transplanting machine is established, a dynamic model of the transplanting machine is established in ADAMS according to the three-dimensional model of the transplanting machine; a mathematical model of a driving motor of the transplanting machine is established; an integral sliding surface is set based on a defined angle tracking error variable, the integral sliding surface is normalized by using a nonlinear function, and a control input is calculated according to a state of the integral sliding surface and an estimated value of an active disturbance rejection extended state observer; a total disturbance estimated value of a controlled system is realized by the nonlinear extended state observer in combination with a measured actual angle, and a variable sliding surface active disturbance rejection controller is obtained by combining a variable sliding surface output and a disturbance estimation. The variable sliding surface active disturbance rejection controller controls the extension and retraction of a servo cylinder to drive a leveling actuating mechanism to swing, thereby realizing the rapid leveling of the lateral angle of the transplanting machine.

Description

Technical Field

[0001] This invention relates to agricultural machinery and its leveling technology, particularly a transplanter and its lateral leveling method and apparatus based on variant synovial self-disturbance control. Background Technology

[0002] Vegetable cultivation mostly employs seedling transplanting. However, in complex terrains such as hilly areas, existing transplanters are inefficient, lack automation, and struggle to achieve stable operation and guarantee transplanting accuracy. Early leveling systems relied on mechanical or simple hydraulic control, lacking real-time posture detection capabilities and the ability to adjust planting posture according to terrain, leading to uneven transplanting depth or seedling damage. During operation, mechanical impacts from the planting and seedling-retrieving mechanisms affect the stability of the transplanter's lateral horizontal angle. For transplanters, leveling time, leveling accuracy, and anti-interference capability are three crucial indicators of the leveling system. Existing leveling control primarily uses PID algorithms, with fuzzy control and other methods introduced. However, these methods require high accuracy in system modeling and are limited in response speed and accuracy under nonlinear and time-varying disturbances. Furthermore, the coordination efficiency between the algorithm and the execution mechanism is low. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to address the above-mentioned deficiencies of the prior art by providing a transplanter and a leveling method and apparatus based on variant synovial self-disturbance control.

[0004] To achieve the above objectives, the present invention provides a leveling device for a transplanter based on variant synovial membrane self-disturbance control, comprising:

[0005] A leveling actuator is mounted on the body of the transplanter and connected to the rear wheels of the transplanter;

[0006] A servo electric cylinder is connected to the leveling actuator.

[0007] A variant slewing self-disruption controller is connected to the servo electric cylinder;

[0008] The variant sliding membrane self-disturbance controller controls the extension and retraction of the servo electric cylinder, which drives the leveling actuator to swing, thereby achieving rapid leveling of the transplanter's lateral angle.

[0009] The leveling device of the transplanter based on variant synovial anti-disturbance control mentioned above, wherein the servo electric cylinder includes a servo motor and a push rod, the servo motor is connected to the variant synovial anti-disturbance controller, and the two ends of the push rod are respectively connected to the servo motor and the leveling actuator.

[0010] The leveling device of the transplanter based on variant synovial self-disturbance control mentioned above, wherein the leveling actuator is in two sets, symmetrically arranged on both sides of the vehicle body and connected to the corresponding rear wheels respectively; a servo electric cylinder is provided for each set of leveling actuators.

[0011] To better achieve the above objectives, the present invention also provides a leveling method for a transplanter based on variant synovial membrane self-disturbance control, wherein the lateral leveling of the transplanter using the above-mentioned leveling device includes the following steps:

[0012] A three-dimensional model of the transplanter is established, and a dynamic model of the transplanter is established in ADAMS based on the three-dimensional model of the transplanter.

[0013] Establish a mathematical model for the drive motor of the transplanter;

[0014] The integral sliding surface is set based on the defined angle tracking error variable, and the integral sliding surface is normalized using a nonlinear function. The control input is calculated based on the state of the integral sliding surface and the estimated value of the active disturbance rejection extended state observer.

[0015] By using the nonlinear extended state observer and combining it with the measured actual angle, the total disturbance estimate of the controlled system is obtained, and the variant sliding diaphragm output is combined with the disturbance estimate to obtain the variant sliding diaphragm active disturbance rejection controller.

[0016] A control simulation module for the transplanter and servo motor was built by combining a variant synovial active disturbance rejection controller. By adjusting the parameters of the variant synovial active disturbance rejection controller, the lateral angle of the transplanter can be quickly leveled.

[0017] The aforementioned leveling method for transplanters based on variant synovial active disturbance rejection control, wherein the variant synovial active disturbance rejection controller is obtained in the following manner:

[0018] Define the angle error variable:

[0019]

[0020] Where θ e Let θ be the target angular velocity. a e1 is the actual angular velocity, e2 is the error between the target position and the actual position, and e2 is the derivative of the error between the target position and the actual position.

[0021] Based on the angle error variable, a proportional-integral-differential composite sliding surface is set to ensure that the sliding surface contains complete information about the error dynamics. An integral term is introduced to compensate for system uncertainties through error accumulation, thereby achieving complete suppression of matching disturbances. The integral sliding surface s is:

[0022]

[0023] Where λ, γ, and β are adjustment parameters;

[0024] To avoid high-frequency chattering of the control input caused by traditional symbolic functions, a continuous saturation function is used, and the sliding surface is normalized as follows:

[0025]

[0026] Where δ0, k, and α are adjustment parameters, δ(t) has dynamic decay characteristics. As time goes by, the exponential term approaches zero, and the function approaches the saturation characteristics of the boundary layer thickness α. While retaining sliding mode robustness, the steady-state error and chattering amplitude are balanced by adjusting α. The dynamic trade-off between chattering suppression and convergence accuracy is achieved through time-varying parameters. The continuity of the function ensures that the control law is differentiable.

[0027] The above-mentioned leveling method for transplanters based on variant synovial self-disturbance control uses Lyapunov's stability theorem to verify the stability of variant synovial control.

[0028] The aforementioned leveling method for transplanters based on variant synovial active disturbance rejection control, wherein the active disturbance rejection extended state observer is:

[0029]

[0030] In the formula, e is the difference between the estimated tilt angle and the actual angle, z1 is the estimated value of the actual angle, z2 is the estimated value of the tilt angular velocity, z3 is the estimated value of the total disturbance, β1, β2, and β3 are the error gains of each order of the nonlinear active disturbance rejection extended state observer, which are adjusted by the bandwidth method to make the parameters of the nonlinear active disturbance rejection extended state observer easy to adjust and the error converge, and ω0 is the observer bandwidth.

[0031] The aforementioned leveling method for transplanters based on variant synovial active disturbance rejection control further includes the step of establishing a dynamic model of the transplanter in ADAMS based on the three-dimensional model of the transplanter:

[0032] The transplanter was simplified, retaining only the key actuators, including the front wheels, rear wheels, vehicle body, front axle, rear axle, and leveling actuator. A three-dimensional model of the transplanter was obtained using SolidWorks.

[0033] The 3D model of the transplanter was imported into ADAMS and constraints were added to obtain the dynamic model of the transplanter.

[0034] The aforementioned leveling method for transplanters based on variant synovial active disturbance rejection control, wherein step 2, establishing the mathematical model of the transplanter's drive motor, further includes:

[0035] The transplanter's drive motor is a servo motor, and the motor model was built using MATLAB / Simulink.

[0036] To better achieve the above objectives, the present invention also provides a transplanter, which includes the above-mentioned leveling device based on variant synovial self-disturbance control, and uses the above-mentioned leveling method based on variant synovial self-disturbance control for lateral leveling.

[0037] The technical advantages of this invention are as follows:

[0038] This invention improves the leveling speed of transplanters and solves the problems of weak anti-interference ability of transplanters under nonlinear and time-varying disturbances, as well as the slow convergence speed and poor anti-interference ability of existing leveling controllers in application. The sliding surface is set as a composite structure containing proportional, integral and differential functions to ensure that the sliding surface contains complete information of error dynamics. An integral term is introduced to achieve compensation for system uncertainty through error accumulation, thereby forming complete suppression of matching disturbances.

[0039] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention. Attached Figure Description

[0040] Figure 1 This is a structural block diagram of a leveling device according to an embodiment of the present invention;

[0041] Figure 2 This is a schematic diagram illustrating the working principle of a variant of the sliding diaphragm active disturbance rejection controller according to an embodiment of the present invention.

[0042] Figure 3 This is a schematic diagram of a servo motor control principle according to an embodiment of the present invention;

[0043] Figure 4 This is a joint simulation model of ADAMS and MATLAB / Simulink according to an embodiment of the present invention;

[0044] Figure 5 This is a schematic diagram of a variant sliding membrane active disturbance rejection controller constructed according to an embodiment of the present invention;

[0045] Figure 6 This is a simulation result diagram of leveling according to an embodiment of the present invention;

[0046] Figure 7 This is a simplified structural diagram of a transplanter in SolidWorks according to an embodiment of the present invention;

[0047] Figure 8 This is a schematic diagram of the leveling principle of a transplanter according to an embodiment of the present invention.

[0048] Among them, the attached reference numerals

[0049] 1. Car body

[0050] 2 front wheels

[0051] 3 rear wheels

[0052] 4. Leveling device

[0053] 41 Mediation and Implementation Agencies

[0054] 42 servo electric cylinder

[0055] 421 servo motor

[0056] 422 Servo Actuator

[0057] 43 variant slug self-disturbance rejection controller

[0058] 5 rear axles

[0059] 6. Front axle attitude adjustment mechanism

[0060] 7 tilt sensors

[0061] 8 front axles

[0062] 100 transplanter Detailed Implementation

[0063] The structural and working principles of the present invention will be described in detail below with reference to the accompanying drawings:

[0064] The transplanter 100 of this invention, including its components, structure, relative positions, connections, and functions, are all relatively mature existing technologies. Its difference from existing technologies lies in the inclusion of a leveling device 4 based on variant synovial self-disturbance rejection control, and the use of a leveling method based on variant synovial self-disturbance rejection control for lateral leveling. This leveling device 4 and method based on variant synovial self-disturbance rejection control are used for leveling the transplanter 100 in hilly and mountainous areas. Based on variant synovial self-disturbance rejection control, it effectively solves the problems of weak anti-interference ability and slow leveling speed of the transplanter 100 when working in hilly and mountainous areas. Simultaneously, the use of a co-simulation method allows for better simulation of the leveling process, facilitating the analysis of the dynamic characteristics during the simulation process.

[0065] See Figure 1 , Figure 1This is a structural block diagram of a leveling device 4 according to an embodiment of the present invention. The leveling device 4 of the transplanter 100 based on variant synovial anti-disturbance control includes: a leveling actuator 41, mounted on the body 1 of the transplanter 100 and connected to the rear wheel 3 of the transplanter 100; a servo cylinder 42 connected to the leveling actuator 41; and a variant synovial anti-disturbance controller 43 connected to the servo cylinder 42. The variant synovial anti-disturbance controller 43 controls the extension and retraction of the servo cylinder 42, causing the leveling actuator 41 to swing, thereby achieving rapid leveling of the lateral angle of the transplanter 100. In this embodiment, the servo cylinder 42 includes a servo motor 421 and a push rod. The servo motor 421 is connected to the variant synovial anti-disturbance controller 43, and both ends of the push rod are connected to the servo motor 421 and the leveling actuator 41, respectively. Preferably, there are two sets of leveling actuators 41, which are symmetrically arranged on both sides of the vehicle body 1 and connected to the corresponding rear wheels 3 respectively; a servo electric cylinder 42 is provided for each set of leveling actuators 41.

[0066] See Figure 2 and Figure 3 , Figure 2 This is a schematic diagram illustrating the working principle of a variant sliding diaphragm active disturbance rejection controller 43 according to an embodiment of the present invention. Figure 3 This is a schematic diagram of the control principle of the servo motor 421 according to an embodiment of the present invention. The leveling method of the transplanter 100 based on variant slipform active disturbance rejection control of the present invention uses the aforementioned leveling device 4 to perform lateral leveling of the transplanter 100, and includes the following steps:

[0067] Step 1: Establish a 3D model of the transplanter 100. In ADAMS, establish a dynamic model of the transplanter 100 based on the 3D model of the transplanter 100; further including:

[0068] The transplanter 100 is simplified, retaining only the key execution components, including the vehicle body 1, front wheel 2, rear wheel 3, front axle 8, rear axle 5 and leveling execution mechanism 41. It may also include a front axle attitude adjustment mechanism 6 set on the front axle 8. The three-dimensional model of the transplanter 100 is obtained using SolidWorks.

[0069] Import the 3D model of the transplanter 100 into ADAMS and add constraints to obtain the dynamic model of the transplanter 100.

[0070] Step 2: Establish a mathematical model of the drive motor of the transplanter 100; the drive motor of the transplanter 100 is a servo motor 421, and the motor model is established using MATLAB / Simulink.

[0071] Step 3: Based on the defined angle tracking error variable, set the integral sliding surface. To prevent the sliding surface from being too large and causing excessive control output, a nonlinear function is used to normalize the integral sliding surface s. The control input is calculated based on the state of the integral sliding surface and the estimated value from the active disturbance rejection extended state observer. The active disturbance rejection extended state observer is:

[0072]

[0073] In the formula, e is the difference between the estimated tilt angle and the actual tilt angle, z1 is the estimated value of the actual angle, z2 is the estimated value of the tilt angular velocity, z3 is the estimated value of the total disturbance, β1, β2, and β3 are the error gains of the nonlinear active disturbance rejection extended state observers, which are adjusted using the bandwidth method to make the parameters of the nonlinear active disturbance rejection extended state observers easy to adjust and the error converges, and ω0 is the observer bandwidth.

[0074] Step 4: By using the nonlinear extended state observer and combining it with the measured actual angle, the total disturbance of the controlled system is estimated, and the variant sliding diaphragm output is combined with the disturbance estimate to obtain the variant sliding diaphragm active disturbance rejection controller 43; the output voltage of the variant sliding diaphragm active disturbance rejection controller 43 is input to the servo motor 421 to achieve target angle tracking control;

[0075] Step 5: Export the dynamic model of transplanter 100 in ADAMS to generate a MATLAB / Simulink submodule as the transplanter 100 module. Add the servo cylinder 42 model to MATLAB / Simulink and combine it with the set variant sliding membrane active disturbance rejection controller 43. Build a joint simulation model of ADAMS and MATLAB / Simulink in MATLAB / Simulink, combine the control module, servo motor 421 module and dynamics module, assign command signals to it, and achieve rapid leveling of transplanter 100 by adjusting the various parameters in the variant sliding membrane active disturbance rejection controller 43.

[0076] In this embodiment, the variant synovial active disturbance rejection controller 43 is obtained in the following manner:

[0077] Define the angle error variable:

[0078]

[0079] Where θ e Let θ be the target angular velocity. a e1 is the actual angular velocity, e2 is the error between the target position and the actual position, and e2 is the derivative of the error between the target position and the actual position.

[0080] Based on the angle error variable, a proportional-integral-differential composite sliding surface is set to ensure that the sliding surface contains complete information about the error dynamics. An integral term is introduced to compensate for system uncertainties through error accumulation, thereby achieving complete suppression of matching disturbances. The integral sliding surface s is:

[0081]

[0082] Where λ, γ, and β are adjustment parameters;

[0083] To avoid high-frequency chattering of the control input caused by traditional symbolic functions, a continuous saturation function is used, and the sliding surface is normalized as follows:

[0084]

[0085] Where δ0, k, and α are adjustment parameters, δ(t) has dynamic decay characteristics. As time goes by, the exponential term approaches zero, and the function approaches the saturation characteristics of the boundary layer thickness α. While retaining sliding mode robustness, the steady-state error and chattering amplitude are balanced by adjusting α. The dynamic trade-off between chattering suppression and convergence accuracy is achieved through time-varying parameters. The continuity of the function ensures that the control law is differentiable.

[0086] In this embodiment, to verify the stability of the variant synovial controller, Lyapunov's stability theorem is used to prove the stability of the variant synovial controller.

[0087] In one embodiment of the present invention, the lateral leveling method of the transplanter 100 based on variant synovial self-disturbance control includes:

[0088] Step 1: Establish a 3D model of the transplanter 100. Based on the 3D model of the transplanter 100, establish a dynamic model of the transplanter 100. The transplanter 100 is then appropriately simplified, such as... Figure 7 and Figure 8 As shown, the vehicle includes wheels, body 1, front axle, rear axle, leveling actuator 41, and servo cylinder 42. The drawing is done using SolidWorks. Points A and G are fixed points of body 1, B and F are movable hinge points, CE is the rear axle, D and H are the wheel centers of rear wheel 3, and BCD and FEH are fixed connecting rods with an angle of 90°. Leveling is achieved by extending AB and retracting GF, or by retracting AB and extending GF to drive the leveling actuator 41 to rotate, thus achieving the vehicle's levelness in the x-axis direction.

[0089] The three-dimensional model of the leveling part includes servo electric cylinder 42, leveling actuator 41 and vehicle body 1, and the rest of the structure is appropriately simplified; the leveling method is to achieve the lateral horizontal adjustment of vehicle body 1 by having two servo electric cylinders 42 corresponding to the rear wheel 3 work together to extend one and retract the other.

[0090] Import the 3D model into ADAMS and add constraints: the electric cylinder and the vehicle body 1, the electric cylinder and the actuator are all connected by a revolute joint, the inner push rod and the outer push rod are connected by a prismatic joint, the wheels are in contact with the ground, and the ground is set with an initial slope of 10°.

[0091] Step 2: In this embodiment, two servo motors 421 are set up on the left and right sides. A dynamic model is established for each servo cylinder 42. The rotation of the servo motor 421 provides power to drive the extension and retraction of the push rod. The servo cylinder 42 is a mechanical structural connection combination of the push rod and the servo motor 421. The servo cylinder 42 consists of the servo motor 421 and the push rod. The variant sliding membrane anti-interference controller 43 in the built hardware circuit adopts the single-chip microcomputer STM32F103ZET6. The single-chip microcomputer outputs motor control signals, which drive the servo push rod 422 to move, thereby driving the leveling actuator 41 to move and realize the lateral leveling of the vehicle body 1. The tilt sensor 7 of the vehicle body 1 detects the lateral angle of the vehicle body 1 in real time. The lateral angle signal is input to the single-chip microcomputer, which stores the control program of the variant sliding membrane anti-interference. Figure 3 As shown, a servo motor 421 model was built using MATLAB / Simulink, with identical models for the left and right motors.

[0092] Step 3, based on the servo motor 421 model, set the variant sliding diaphragm active disturbance rejection controller 43, such as... Figure 2 As shown, the steps are as follows:

[0093] For the servo motor 421 model, considering it as a system, its dynamic model is as follows:

[0094]

[0095] Where y represents angular displacement. Indicates angular velocity, Let represent angular acceleration, m be the inertial load, K be the torque constant, u be the control input, and B be the coefficient of friction. This represents other modeled disturbances and other unmodeled dynamics, where t represents time;

[0096] Define the angle error variable:

[0097]

[0098] Where θ e Let θ be the target angular velocity. a e1 is the actual angular velocity, e2 is the error between the target position and the actual position, and e2 is the derivative of the error between the target position and the actual position.

[0099] Based on the angle error variable, a proportional-integral-differential composite sliding surface is set to ensure that the sliding surface contains complete information about the error dynamics. An integral term is introduced to compensate for system uncertainties through error accumulation, thus achieving complete suppression of matching disturbances. Its integral sliding surface s is:

[0100]

[0101] Where λ, γ, and β are adjustment parameters;

[0102] To avoid high-frequency chattering of the control input caused by traditional sign functions, a continuous saturation function is used, and the sliding surface is normalized:

[0103]

[0104] In the formula, δ0, k, and α are adjustment parameters. δ(t) has dynamic decay characteristics. As time goes by, the exponential term approaches zero. At this time, the function approaches the saturation characteristics of the boundary layer thickness α. While retaining the sliding mode robustness, the steady-state error and chattering amplitude are balanced by adjusting α. The dynamic trade-off between chattering suppression and convergence accuracy is achieved through time-varying parameters. The continuity of the function can ensure that the control law is differentiable.

[0105] The servo motor equation 421 can be written in state-space form as follows:

[0106]

[0107] To verify the stability of the variant slug controller, Lyapunov's stability theorem is used to prove its stability.

[0108] From equation (4), we can see that:

[0109]

[0110] From equation (5), we can obtain:

[0111]

[0112] Combining equations (4), (5), and (6), we get:

[0113]

[0114] Differentiate the selected s-plane surface:

[0115]

[0116] Combining equations (7) and (8), we get:

[0117]

[0118] For the gliding surface to converge, the output u of the gliding control needs to satisfy the gliding surface... The stability condition is based on the perturbation estimation of the extended state observer. Assuming that the perturbation compensation is bounded, i.e., |d(x,t)|≤D, according to equation (4), the control input u is:

[0119]

[0120] In the formula, K is the control gain, and K > D;

[0121] Substituting equation (10) into equation (9), we get:

[0122]

[0123] Choose the Lyapunov function:

[0124]

[0125] Its derivative is:

[0126]

[0127] From equation (3), we get:

[0128]

[0129] And |d(x,t)|≤D, therefore we have:

[0130]

[0131] When |s|≠0

[0132]

[0133] Since K>D and Therefore:

[0134] V≤|s|(-K+D)<0;

[0135] Therefore, V is a non-increasing function, and s approaches 0.

[0136] The error, the derivative of the error, and the total disturbance of the system are estimated by the nonlinear extended state observer in active disturbance rejection control. The nonlinear extended state observer is as follows:

[0137]

[0138] In the formula, e is the difference between the estimated tilt angle and the actual angle, z1 is the estimated value of the actual angle, z2 is the estimated value of the tilt angular velocity, z3 is the estimated value of the total disturbance, β1, β2, and β3 are the error gains of the nonlinear extended state observer at each order. In order to make the parameters of the nonlinear extended state observer easy to adjust and the error converge, the bandwidth method is used to adjust it, where the parameter ω0 is the observer bandwidth.

[0139] Step 4: Export the dynamic model of the transplanter 100 from ADAMS to generate a MATLAB / Simulink submodule, which serves as the vehicle module of the transplanter 100. Add the servo electric cylinder 42 model to MATLAB / Simulink and combine it with the configured variant sliding diaphragm active disturbance rejection controller 43, such as... Figure 4 As shown, data from the tilt sensor 7 is fed back to the controller, processed by the control algorithm, and then output to the servo cylinder 42 model to achieve higher precision lateral horizontal adjustment of the transplanter 100. The simulation structure of the variant sliding film self-disruption controller 43 is shown below. Figure 5 As shown.

[0140] The transplanter 100 of this invention was drawn using SolidWorks, and its components were simplified, retaining only the basic parts. The bare weight of the transplanter is 250kg, the stroke of the servo electric cylinder 42 is 0-100mm, the front wheel 2 is the driven wheel, which passively follows the contours of the slope, and the rear wheel 3 is the drive wheel with a wheelbase of 900mm. The ground environment is a contour line operation, that is, the longitudinal slope angle is 0° and the initial transverse slope angle is 10°.

[0141] The output of the variant sliding diaphragm active disturbance rejection controller 43 is sent to the servo motor 421. The servo motor 421 drives the servo push rod 422 to move, which in turn drives the leveling mechanism to achieve the lateral leveling of the vehicle body 1. The vehicle body 1's own sensors detect the lateral angle of the vehicle body 1 in real time. The real-time lateral angle is used as feedback input to the variant sliding diaphragm active disturbance rejection controller 43 to form a complete closed-loop control.

[0142] Based on the above modeling method, the system was simulated, and the simulation results are as follows. Figure 6 As shown, the results are analyzed as follows: the lateral angle of the transplanter 100 reaches a stable state in 5.16s, with a steady-state error of ±0.1°. The variant sliding film active disturbance rejection controller 43 is essentially a combination of variant sliding film control and active disturbance rejection control. The variant sliding film control enables the system output to converge quickly, while the active disturbance rejection control aims to improve the system's anti-interference capability. The combination of these two advantages overcomes the problems of slow leveling speed and weak anti-interference capability. For example... Figure 6The simulation curve shown is the curve of the transplanter 100 adjusting from a tilt angle of 10° to 0° after the simulation is started. The lateral angle of the transplanter 100 is within 0.2° in about 3 seconds, and reaches a stable state in about 5 seconds, almost close to 0°, and then remains stable.

[0143] This invention first establishes a dynamic model of the transplanter 100 based on a three-dimensional model of the transplanter 100; establishes a mathematical model for each leveling servo motor 421; then sets up a variant sliding membrane active disturbance rejection controller 43; exports the transplanter 100 model to generate a MATLAB / Simulink submodule as the transplanter 100 module; adds the servo motor 421 model to MATLAB / Simulink and combines it with the set variant sliding membrane active disturbance rejection controller 43 module to build a control simulation module for the transplanter 100 and servo motor 421; provides a target angle signal; and achieves rapid leveling of the transplanter 100 by adjusting various parameters in the control module, effectively overcoming problems such as slow leveling speed, poor accuracy, and weak anti-interference ability.

[0144] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the appended claims.

Claims

1. A leveling method for a transplanter based on variant synovial self-disturbance control, characterized in that, Includes the following steps: A three-dimensional model of the transplanter is established, and a dynamic model of the transplanter is established in ADAMS based on the three-dimensional model of the transplanter. Establish a mathematical model for the drive motor of the transplanter; The integral sliding surface is set based on the defined angle tracking error variable, and the integral sliding surface is normalized using a nonlinear function. The control input is calculated based on the state of the integral sliding surface and the estimated value of the active disturbance rejection extended state observer. By using the nonlinear extended state observer and combining it with the measured actual angle, the total disturbance of the controlled system can be estimated, and the variant sliding diaphragm output and the disturbance estimate can be combined to obtain the variant sliding diaphragm active disturbance rejection controller. A control simulation module for the transplanter and servo motor was built by combining a variant synovial active disturbance rejection controller. By adjusting the parameters of the variant synovial active disturbance rejection controller, the lateral angle of the transplanter can be quickly leveled.

2. The leveling method for a transplanter based on variant synovial self-disturbance control according to claim 1, characterized in that, The variant synovial active disturbance rejection controller is obtained in the following manner: Define the angle error variable: ； Where θ e Let θ be the target angular velocity. a e1 is the actual angular velocity, e2 is the error between the target position and the actual position, and e2 is the derivative of the error between the target position and the actual position. Based on the angle error variable, a proportional-integral-differential composite sliding surface is set to ensure that the sliding surface contains complete information about the error dynamics. An integral term is introduced to compensate for system uncertainties through error accumulation, thereby achieving complete suppression of matching disturbances. The integral sliding surface s is: ； Where λ, γ, and β are adjustment parameters; To avoid high-frequency chattering of the control input caused by traditional symbolic functions, a continuous saturation function is used, and the sliding surface is normalized as follows: ； Where δ0, k, and α are adjustment parameters, δ(t) has dynamic decay characteristics. As time goes by, the exponential term approaches zero, and the function approaches the saturation characteristics of the boundary layer thickness α. While retaining sliding mode robustness, the steady-state error and chattering amplitude are balanced by adjusting α. The dynamic trade-off between chattering suppression and convergence accuracy is achieved through time-varying parameters. The continuity of the function ensures that the control law is differentiable.

3. The leveling method for a transplanter based on variant synovial self-disturbance control according to claim 2, characterized in that, The stability of the variant synovial control was verified using Lyapunov's stability theorem.

4. The leveling method for a transplanter based on variant synovial membrane self-disturbance control according to claim 1, characterized in that, The active disturbance rejection extended state observer is: ； In the formula, e is the difference between the estimated tilt angle and the actual angle, z1 is the estimated value of the actual angle, z2 is the estimated value of the tilt angular velocity, z3 is the estimated value of the total disturbance, β1, β2, and β3 are the error gains of each order of the nonlinear active disturbance rejection extended state observer, which are adjusted by the bandwidth method to make the parameters of the nonlinear active disturbance rejection extended state observer easy to adjust and the error converge, and ω0 is the observer bandwidth.

5. The leveling method for a transplanter based on variant synovial membrane self-disturbance control according to claim 1, characterized in that, The steps for establishing a dynamic model of a transplanter based on a 3D model of the transplanter in ADAMS further include: The transplanter was simplified, retaining only the key actuators, including the front wheels, rear wheels, vehicle body, front axle, rear axle, and leveling actuator. A three-dimensional model of the transplanter was obtained using SolidWorks. The 3D model of the transplanter was imported into ADAMS and constraints were added to obtain the dynamic model of the transplanter.

6. The leveling method for a transplanter based on variant synovial self-disturbance control according to claim 1, characterized in that, The establishment of a mathematical model for the transplanter's drive motor further includes: The transplanter's drive motor is a servo motor, and the motor model was built using MATLAB / Simulink.

7. A leveling device for a transplanter based on variant synovial membrane self-disturbance control, characterized in that, A leveling method based on variant synovial self-disturbance control for implementing the transplanter according to any one of claims 1-6 includes: A leveling actuator is mounted on the body of the transplanter and connected to the rear wheels of the transplanter; A servo electric cylinder is connected to the leveling actuator. A variant slewing self-disruption controller is connected to the servo electric cylinder; The variant slurry self-disturbance controller controls the extension and retraction of the servo electric cylinder, which drives the leveling actuator to swing, thereby achieving rapid leveling of the transplanter's lateral angle.

8. The leveling device for a transplanter based on variant synovial self-disturbance control as described in claim 7, characterized in that, The servo electric cylinder includes a servo motor and a push rod. The servo motor is connected to the variant sliding diaphragm anti-disturbance controller, and the two ends of the push rod are respectively connected to the servo motor and the leveling actuator.

9. The leveling device for a transplanter based on variant synovial membrane self-disturbance control as described in claim 7 or 8, characterized in that, The leveling actuator consists of two sets, which are symmetrically arranged on both sides of the vehicle body and connected to the corresponding rear wheels; a servo electric cylinder is provided for each set of the leveling actuator.

10. A transplanter, characterized in that, The device includes the leveling apparatus based on variant synovial self-disturbance control as described in any one of claims 7-9, and the leveling method based on variant synovial self-disturbance control as described in any one of claims 1-6 is used for lateral leveling.

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