A vibration reduction control method, system and device for a wheel-legged multi-modal unmanned platform

Abstract

The present invention discloses a vibration reduction control method, system and equipment for a wheel-leg multi-modal unmanned platform, which relates to the field of vibration reduction control. The method includes taking the passive suspension vibration reduction system of the whole vehicle as an ideal reference model, building an ideal virtual equivalent vibration reduction system; constructing an objective function with spring stiffness and damping coefficient as variables to be optimized according to the ideal virtual equivalent vibration reduction system, task requirements and key responses; determining the optimal spring stiffness and optimal damping coefficient according to the objective function; constructing a wheel-leg mechanism kinematic model; and determining the foot-end motion expression according to the wheel-leg mechanism kinematic model; determining the motion Jacobian matrix according to the foot-end motion expression; constructing an equivalent passive spring-damping vibration reduction system according to the optimal spring stiffness, the optimal damping coefficient, the foot-end motion expression and the motion Jacobian matrix; and performing response tracking according to the equivalent passive spring-damping vibration reduction system. The present invention can improve the transportation efficiency and driving stability of the wheel-leg multi-modal unmanned platform.

Description

Technical Field

[0001] The present invention relates to the field of vibration reduction control, and in particular to a vibration reduction control method, system and equipment for a wheel-legged multi-modal unmanned platform. Background Art

[0002] The wheel-legged multi-modal unmanned platform is an unmanned mobile platform that combines wheeled motion mode and legged motion mode. The platform switches between different motion modes such as wheeled and legged according to different environments. On relatively flat roads, it uses wheeled mode to travel quickly; on complex or irregular terrain, it uses legged mode to travel. Compared with traditional leg-footed unmanned platforms, wheel-legged multi-modal unmanned platforms have higher speed and mobility, higher motion efficiency, greater flexibility and greater carrying capacity, and will be an important development direction for unmanned mobile platforms in the future.

[0003] Although the wheel-legged multi-modal unmanned platform has significant advantages in movement speed and stability, when the wheel-legged multi-modal unmanned platform is driving quickly over bumps, potholes or uneven roads in a wheeled state, its overall movement state and driving performance are still easily affected by vibration. The effects of these vibrations (such as higher sprung acceleration and changes in vehicle posture) will not only reduce the efficiency of the unmanned platform's driving, but also cause damage to the unmanned platform's moving parts, sensors and other precision components.

[0004] For the joint torque control of wheel-leg multimodal unmanned platform, the most widely used method at present is to install hydraulic and other actuating elements at the wheel-leg joints, generate hydraulic pressure by controlling the actuating mechanism, and multiply it by the joint lever arm to generate torque, thereby completing the torque control of the wheel-leg joint. However, this method requires the installation of hydraulic actuating elements at the thigh and calf, which increases the mass of the leg parts. At the same time, when the wheel-leg joint moves due to road excitation, the actuating force of the actuator at the joint changes due to the joint lever arm, resulting in a non-linear change in torque, which is not conducive to the precise control of the torque. In order to solve the problems of the change of the actuating force lever arm and the slow response of the hydraulic motor, the present invention directly controls the torque at the wheel-leg joint by directly installing the actuating element at the joint.

[0005] For the vibration reduction control of the wheel-legged multi-modal unmanned platform in the wheeled state, the existing method is usually to install passive damping and spring elements at the joints or equivalent positions to attenuate the suspension vibration through springs and damping. This method increases the leg mass and reduces the movement flexibility and rapidity of the wheel-legged unmanned platform in the footed state. The present invention designs a set of ideal model reference wheel-legged multi-modal unmanned platform vibration reduction control algorithms, which directly complete the virtual spring and virtual damping equivalence by controlling the joint motor torque, thereby completing the vibration reduction control of the wheel-legged multi-modal unmanned platform.

[0006] The design problem of spring stiffness and damping coefficient in vibration reduction control of wheel-legged multi-modal unmanned platform is addressed. In order to meet the requirements of motion range and flexibility, the existing wheel-legged unmanned platform usually sets the passive spring stiffness and damping coefficient to a fixed value. This method cannot meet the vibration reduction requirements of wheel-legged unmanned platform under different driving conditions. Summary of the invention

[0007] The purpose of the present invention is to provide a vibration reduction control method, system and equipment for a wheel-legged multi-modal unmanned platform, which can improve the transportation efficiency and driving stability of the wheel-legged multi-modal unmanned platform.

[0008] To achieve the above object, the present invention provides the following solutions:

[0009] A vibration reduction control method for a wheel-legged multi-modal unmanned platform, comprising:

[0010] The driving module is arranged at the wheel-leg joint of the wheel-leg multi-modal unmanned platform; the driving module is used to control the torque output at the wheel-leg joint to achieve direct control of the hip joint movement and knee joint movement of the wheel-leg multi-modal unmanned platform;

[0011] Taking the whole vehicle passive suspension vibration reduction system as an ideal reference model, an ideal virtual equivalent vibration reduction system of the wheel-legged multi-modal unmanned platform is constructed; the whole vehicle passive suspension vibration reduction system has the same size parameters, tire parameters, whole vehicle mass and tire mass as the wheel-legged multi-modal unmanned platform; the whole vehicle passive suspension vibration reduction system includes: spring stiffness and damping coefficient;

[0012] According to the ideal virtual equivalent vibration reduction system, task requirements and corresponding key responses, an objective function is constructed with spring stiffness and damping coefficient as variables to be optimized; and the optimal spring stiffness and optimal damping coefficient are determined according to the objective function;

[0013] Construct the kinematic model of the wheel-leg mechanism of the wheel-leg multimodal unmanned platform; and determine the foot end motion expression based on the kinematic model of the wheel-leg mechanism;

[0014] Determine the motion Jacobian matrix based on the foot end motion expression;

[0015] An equivalent passive spring-damper vibration reduction system is constructed based on the optimal spring stiffness, optimal damping coefficient, foot end motion expression and motion Jacobian matrix;

[0016] Response tracking based on an equivalent passive spring-damper vibration reduction system.

[0017] Optionally, the objective function is constructed based on the ideal virtual equivalent vibration reduction system, task requirements and corresponding key responses, with spring stiffness and damping coefficient as variables to be optimized, specifically including:

[0018]

[0019] Among them, f(X)=λ1·f1+λ2·f2+...+λ n ·f n ,f1,f2,...,f n are different key responses, λ1,λ2,...,λ n is the weight value, which is determined according to the task requirements. X is the variable to be optimized. k and c represent the spring stiffness and damping coefficient of the front, rear, left and right wheels respectively. Subscripts 1, 2, 3 and 4 represent the left front wheel, right front wheel, left rear wheel and right rear wheel respectively. f(X) is the objective function. g(X) and h(X) are the equality constraints and inequality constraints respectively. Subscripts j and k represent the serial numbers of the actual constraint inequalities respectively.

[0020] Optionally, the step of constructing a kinematic model of a wheel-leg mechanism of the wheel-leg multimodal unmanned platform; and determining a foot-end motion expression according to the kinematic model of the wheel-leg mechanism, specifically includes:

[0021] According to the wheel-legged multimodal unmanned platform, the Denavit-Hartenberg convention method is used to establish the reference coordinate system of each joint;

[0022] According to the reference coordinate system of each joint, the forward and inverse kinematics analysis of the two-link mechanism of the wheel-leg configuration of the wheel-leg multimodal unmanned platform is performed to obtain the foot end motion expression.

[0023] Optionally, the foot end motion expression is:

[0024]

[0025]

[0026] Where x, y are the foot end positions, is the foot velocity, a1 and a2 represent the thigh and calf lengths respectively, θ1 and θ2 represent the rotation angles of the hip joint in the coordinate system X0-Y0 and the knee joint in the coordinate system X1-Y1 respectively, and X0-Y0 and X1-Y1 represent the hip joint coordinate system and the knee joint coordinate system respectively.

[0027] Optionally, determining the motion Jacobian matrix according to the foot end motion expression specifically includes:

[0028]

[0029] Where J is the motion Jacobian matrix.

[0030] Optionally, constructing an equivalent passive spring-damper vibration reduction system according to the optimal spring stiffness, the optimal damping coefficient, the foot end motion expression and the motion Jacobian matrix specifically includes:

[0031] [τ1,τ2]=J T (F x +F y );

[0032] Among them, J T is the transpose of the Jacobian matrix, F x =F k,x +F c,x is the longitudinal force at the foot end, is the longitudinal spring force, is the vertical spring force, are the optimal longitudinal spring stiffness and vertical spring stiffness, respectively. Δx and Δy are the longitudinal wheel-leg displacement and vertical wheel-leg displacement, respectively. y =F k,y +F c,y is the vertical force at the foot end, is the longitudinal damping force, is the vertical damping force, c x and c y are the longitudinal spring stiffness and the vertical spring stiffness, and are the longitudinal wheel-leg speed and the vertical wheel-leg speed, τ1 and τ2 are the calculated joint torques.

[0033] A wheel-legged multi-modal unmanned platform vibration reduction control system, comprising:

[0034] A drive position determination unit is used to set a drive module at the wheel-leg joint of the wheel-leg multimodal unmanned platform; the drive module is used to control the torque output at the wheel-leg joint to achieve direct control of the hip joint movement and knee joint movement of the wheel-leg multimodal unmanned platform;

[0035] An ideal virtual equivalent vibration reduction system building unit is used to build an ideal virtual equivalent vibration reduction system for a wheel-legged multi-modal unmanned platform by taking the whole vehicle passive suspension vibration reduction system as an ideal reference model; the whole vehicle passive suspension vibration reduction system has the same size parameters, tire parameters, whole vehicle mass and tire mass as the wheel-legged multi-modal unmanned platform; the whole vehicle passive suspension vibration reduction system includes: spring stiffness and damping coefficient;

[0036] An objective function construction unit is used to construct an objective function based on an ideal virtual equivalent vibration reduction system, task requirements and corresponding key responses, with spring stiffness and damping coefficient as variables to be optimized; and determine an optimal spring stiffness and an optimal damping coefficient based on the objective function;

[0037] The foot end motion expression determination unit is used to construct a wheel-leg mechanism kinematic model of the wheel-leg multimodal unmanned platform; and determine the foot end motion expression according to the wheel-leg mechanism kinematic model;

[0038] A motion Jacobian matrix determining unit, used for determining the motion Jacobian matrix according to the foot end motion expression;

[0039] An equivalent passive spring-damper vibration reduction system construction unit is used to construct an equivalent passive spring-damper vibration reduction system according to an optimal spring stiffness, an optimal damping coefficient, a foot end motion expression, and a motion Jacobian matrix;

[0040] The response tracking unit is used to perform response tracking according to an equivalent passive spring-damper vibration reduction system.

[0041] A vibration reduction control device for a wheel-legged multi-modal unmanned platform comprises: at least one processor, at least one memory and computer program instructions stored in the memory, and the method described is implemented when the computer program instructions are executed by the processor.

[0042] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0043] The present invention provides a wheel-leg multi-modal unmanned platform vibration reduction control method, system and equipment. According to the ideal virtual equivalent vibration reduction system, task requirements and corresponding key responses, the objective function is constructed with spring stiffness and damping coefficient as variables to be optimized; and the optimal spring stiffness and optimal damping coefficient are determined according to the objective function; that is, the whole vehicle response optimization objective function is designed according to different actual needs (such as mainly reducing the vibration acceleration of the fuselage on uneven roads such as grass, and mainly reducing the pitch and roll angle when passing through bumps or pits), and the virtual spring stiffness and virtual damping coefficient of each wheel are used as optimization variables for optimization design, so as to achieve the real-time control output of the optimal damping / spring force of the wheel-leg multi-modal unmanned platform. The present invention can make the wheel-leg multi-modal unmanned platform track the response of the ideal vehicle suspension model vibration reduction system by applying control force / torque when it is continuously excited by uneven road surface, so that the wheel-leg multi-modal unmanned platform has the vibration reduction characteristics of the passive spring-damping system, thereby suppressing the negative effects caused by vehicle body vibration, and improving the transportation efficiency and driving stability of the wheel-leg multi-modal unmanned platform. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 A schematic diagram of a wheel-legged multi-modal unmanned platform configuration provided by the present invention;

[0046] Figure 2 A schematic flow chart of a vibration reduction control method for a wheel-legged multi-modal unmanned platform provided by the present invention;

[0047] Figure 3 A schematic diagram of the principle of a vibration reduction control method for a wheel-legged multi-modal unmanned platform provided by the present invention;

[0048] Figure 4 A design diagram of a vibration reduction control method for a wheel-legged multi-modal unmanned platform provided by the present invention;

[0049] Figure 5 It is a schematic diagram of the actuation mode of a wheel-legged multi-modal unmanned platform;

[0050] Figure 6 This is a schematic diagram of the passive vibration reduction system of the whole vehicle;

[0051] Figure 7 It is a schematic diagram of the kinematic model of the wheel-leg mechanism;

[0052] Figure 8 Schematic diagram of the equivalent passive spring-damper vibration reduction system. DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] The purpose of the present invention is to provide a vibration reduction control method, system and equipment for a wheel-legged multi-modal unmanned platform, which can improve the transportation efficiency and driving stability of the wheel-legged multi-modal unmanned platform.

[0055] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0056] like Figure 1 As shown in the figure, the wheel-legged multi-modal unmanned platform has two motion modes: legged motion and wheeled motion. When the vehicle brakes, the wheel-legged multi-modal unmanned platform can complete bionic motion behaviors such as walking and climbing stairs. When the unmanned platform moves in a wheeled state, when driving through potholes, bumps or uneven roads, it is necessary to design a vibration reduction control method to reduce the vibration of the unmanned platform body and improve the unmanned platform's travel efficiency. Figure 3 and Figure 4 As shown, the present invention consists of three parts: drive module construction, ideal model construction and vibration reduction control design.

[0057] Driving module construction. According to the mechanical layout structure of the wheel-legged multi-modal unmanned platform, the driving mode is selected in combination with actual needs. When the required actuating torque is large, hydraulic transmission and other methods are used to apply the control torque. When the required torque is small but the response accuracy requirement is high, a motor and other methods are used to apply the actuating torque. In terms of selecting the driving position, the present invention adopts the method of arranging the torque actuating element at the joint to complete the direct control of the joint torque of the wheel-legged unmanned platform.

[0058] Ideal model optimization. In order to realize the virtual passive vibration reduction design of the wheel-leg unmanned platform, it is necessary to determine the parameters of the referenced ideal vibration model. The present invention takes the whole vehicle suspension vibration reduction system as the ideal model, based on the actual physical parameters of the wheel-leg unmanned platform system (mass and inertia of each part), according to the task requirements (control platform posture control, vibration acceleration, longitudinal acceleration, etc.), builds the objective function, takes the spring stiffness and damping coefficient in the ideal model as the optimization variables, and adopts the optimization design method to obtain the optimal ideal spring stiffness and damping coefficient, and completes the establishment of the ideal wheel-leg vehicle vibration reduction reference model.

[0059] Vibration reduction control design. The vibration reduction control of the wheel-leg unmanned platform takes the ideal passive spring-damper system as the reference model. By controlling the joint driving torque, the ideal model response tracking is completed, thereby realizing the virtual spring-damper vibration reduction design of the entire unmanned platform in the wheeled state. The first is kinematic analysis. The kinematic modeling of the unmanned platform is completed according to the wheel-leg structure. The forward and inverse kinematic calculations are completed according to the wheel-leg movement mode to obtain the Jacobian matrix of the wheel-leg unmanned platform system. Then there is the dynamic analysis. According to the Jacobian matrix obtained by the kinematic analysis, combined with the static / dynamic characteristics of the wheel-leg system, the required control torque is distributed to the joint torque output element, completing the equivalent construction of the wheel-leg system to the ideal reference model, and realizing the design of the whole vehicle virtual spring-damper vibration reduction system of the wheel-leg system.

[0060] like Figure 2 As shown, the present invention provides a vibration reduction control method for a wheel-legged multi-modal unmanned platform, comprising:

[0061] S101, setting a driving module at the wheel-leg joint of the wheel-leg multimodal unmanned platform; the driving module is used to control the torque output at the wheel-leg joint to achieve direct control of the hip joint movement and knee joint movement of the wheel-leg multimodal unmanned platform.

[0062] The hydraulic actuator has a large output force (torque) range, but a slow response. The motor actuator has a smaller output force (torque), but a faster response. The wheel-legged multi-modal unmanned platform selected in this example has a lighter overall mass and requires less control force. Therefore, in order to ensure the control accuracy and operating efficiency of the joint torque, the motor actuator is selected as the driving mechanism to control the torque output. The present invention uses a permanent magnet synchronous motor to control the joint torque. The motor comprises a stator and a rotor. After the torque command is issued by the upper controller, the output torque of the rotor is controlled by controlling the size and on-off of the three winding voltages on the stator.

[0063] In order to ensure the accuracy of the control torque, the present invention directly arranges the motor at the wheel-leg joint, and directly controls the hip joint movement and knee joint movement of the unmanned platform by directly outputting torque at the wheel-leg joint. Figure 5 shown.

[0064] S102, taking the whole vehicle passive suspension vibration reduction system as an ideal reference model, constructing an ideal virtual equivalent vibration reduction system for the wheel-legged multi-modal unmanned platform; the whole vehicle passive suspension vibration reduction system has the same size parameters, tire parameters, whole vehicle mass and tire mass as the wheel-legged multi-modal unmanned platform; the whole vehicle passive suspension vibration reduction system includes: spring stiffness and damping coefficient. Figure 6 As shown in the figure, for the passive suspension system of the whole vehicle, the size parameters and tire parameters are consistent with the parameters of the actual wheel-legged multi-modal unmanned platform. The other main parameters are the vehicle mass M0, tire mass m0, spring stiffness k0 and damping coefficient c0, among which the ideal vehicle mass M0 and tire mass m0 are equal to the actual platform mass M and wheel-leg mass m of the wheel-legged multi-modal unmanned platform, B is the body width, and a and b are the lengths of the front and rear axles.

[0065] The spring stiffness k0 and damping coefficient c0 of each suspension system need to be estimated based on the natural frequency f0 and damping ratio ζ, where:

[0066]

[0067] To ensure the smoothness of the wheel-leg system during driving, the natural frequency should be 1-1.6 Hz and the damping ratio should be 0.1-0.4. The natural frequency and damping ratio are selected within the recommended range according to the actual system, so as to obtain the range of values ​​of the reference spring stiffness k0 and damping coefficient c0 of the ideal reference model.

[0068] S103, constructing an objective function with spring stiffness and damping coefficient as variables to be optimized according to the ideal virtual equivalent vibration reduction system, task requirements and corresponding key responses; and determining the optimal spring stiffness k according to the objective function * and the optimal damping coefficient c * .

[0069] The wheeled multi-modal unmanned platform mainly performs tasks such as fast, long-distance and stable transportation of goods and search for targets in the wheeled state. In this mission scenario, the unmanned platform needs to pass through complex environments such as ruins, roads and fields. According to the mission requirements, when the unmanned platform passes through random roads such as grass, in order to ensure the safety performance of the precision components carried on the platform, the vibration reduction system should focus on reducing the vertical vibration of the vehicle body, and the main indicator is the vertical acceleration of the vehicle body; when the unmanned platform passes through medium and large obstacles such as pits and steps, in order to ensure the stability of the platform loading goods and overall driving, the vibration reduction system should focus on maintaining the body movement posture, and the main indicators are the body pitch angle and roll angle. According to the actual mission requirements, the optimization objective function is constructed with key responses such as body vibration acceleration, pitch angle and roll angle.

[0070] The suspension spring stiffness k and damping coefficient c of the passive vibration reduction system of the whole vehicle are the variables to be optimized. Under given step excitation or random road excitation conditions, the optimization design method is used to obtain the optimal ideal spring stiffness and damping coefficient of each wheel leg, thereby completing the establishment of the ideal reference model.

[0071] S103 specifically includes:

[0072]

[0073] Among them, f(X)=λ1·f1+λ2·f2+...+λ n ·f n ,f1,f2,...,f n are different key responses, λ1,λ2,...,λ n is the weight value, which is determined according to the task requirements. X is the variable to be optimized. k and c represent the spring stiffness and damping coefficient of the front, rear, left and right wheels respectively. Subscripts 1, 2, 3 and 4 represent the left front wheel, right front wheel, left rear wheel and right rear wheel respectively. f(X) is the objective function, which is a weighted combination of optimization objectives, such as sprung mass acceleration and body posture. g(X) and h(X) are equality constraints and inequality constraints, such as wheel-leg motion range and torque change rate limit. Subscripts j and k represent the serial numbers of the actual constraint inequalities respectively.

[0074] S104, constructing a kinematic model of the wheel-leg mechanism of the wheel-leg multimodal unmanned platform; and determining a foot-end motion expression based on the kinematic model of the wheel-leg mechanism.

[0075] S104 specifically includes:

[0076] According to the wheel-legged multimodal unmanned platform, the Denavit-Hartenberg convention method is used to establish the reference coordinate system of each joint, such as Figure 5 shown.

[0077] According to the reference coordinate system of each joint, the forward and inverse kinematics analysis of the two-link mechanism of the wheel-leg configuration of the wheel-leg multimodal unmanned platform is performed to obtain the foot end motion expression.

[0078] The foot end motion expression is:

[0079]

[0080]

[0081] Where x, y are the foot end positions, is the foot end velocity, a1 and a2 represent the thigh and calf lengths respectively, θ1 and θ2 represent the rotation angles of the hip joint in the coordinate system X0-Y0 and the knee joint in the coordinate system X1-Y1 respectively, and X0-Y0, X1-Y1 and X2-Y2 represent the hip joint coordinate system, the knee joint coordinate system and the local wheel coordinate system respectively.

[0082] S105, determining the motion Jacobian matrix according to the foot end motion expression.

[0083] S105 specifically includes:

[0084]

[0085] Where J is the motion Jacobian matrix.

[0086] Let F = (F x ,F y ,F z ,n x ,n y ,n z ) T Let F denote the force and torque vector at the foot end, and let τ denote the torque vector at the corresponding joint. Then the relationship between F and τ is as follows:

[0087] τ=J T F.

[0088] Among them, J T The transpose of the Jacobian matrix is ​​obtained for kinematic analysis. This expression can be used to construct an equivalent linear force required at the foot end and the torque generated by the joint.

[0089] S106, construct an equivalent passive spring-damper vibration reduction system based on the optimal spring stiffness, the optimal damping coefficient, the foot end motion expression and the motion Jacobian matrix.

[0090] S107, performing response tracking according to an equivalent passive spring-damper vibration reduction system.

[0091] S107 specifically includes:

[0092] [τ1,τ2]=JT (F x +F y ).

[0093] Among them, J T is the transpose of the Jacobian matrix, F x =F k,x +F c,x is the longitudinal force at the foot end, is the longitudinal spring force, is the vertical spring force, are the optimal longitudinal spring stiffness and vertical spring stiffness, respectively. Δx and Δy are the longitudinal wheel-leg displacement and vertical wheel-leg displacement, respectively. y =F k,y +F c,y is the vertical force at the foot end, is the longitudinal damping force, is the vertical damping force, c x and c y are the longitudinal spring stiffness and the vertical spring stiffness, and are the longitudinal wheel-leg speed and the vertical wheel-leg speed, τ1 and τ2 are the calculated joint torques.

[0094] By allocating the required joint torques τ1 and τ2 to the joint motor outputs, an equivalent passive spring-damper vibration reduction system can be constructed to complete the response tracking of the ideal vehicle passive suspension model, thereby realizing the design of the vehicle vibration reduction control system for the wheel-legged unmanned platform. Figure 8 shown.

[0095] As another specific embodiment, the present invention provides a wheel-legged multi-modal unmanned platform vibration reduction control system, comprising:

[0096] The drive position determination unit is used to set the drive module at the wheel-leg joint of the wheel-leg multimodal unmanned platform; the drive module is used to control the torque output at the wheel-leg joint to complete the direct control of the hip joint movement and knee joint movement of the wheel-leg multimodal unmanned platform.

[0097] An ideal virtual equivalent vibration reduction system building unit is used to build an ideal virtual equivalent vibration reduction system for a wheel-legged multimodal unmanned platform by taking the passive suspension vibration reduction system of the whole vehicle as an ideal reference model; the passive suspension vibration reduction system of the whole vehicle has the same size parameters, tire parameters, whole vehicle mass and tire mass as the wheel-legged multimodal unmanned platform; the passive suspension vibration reduction system of the whole vehicle includes: spring stiffness and damping coefficient.

[0098] The objective function construction unit is used to construct the objective function based on the ideal virtual equivalent vibration reduction system, task requirements and corresponding key responses, with the spring stiffness and damping coefficient as the variables to be optimized; and determine the optimal spring stiffness and optimal damping coefficient based on the objective function.

[0099] The foot-end motion expression determination unit is used to construct a wheel-leg mechanism kinematic model of the wheel-leg multimodal unmanned platform; and determine the foot-end motion expression based on the wheel-leg mechanism kinematic model.

[0100] The motion Jacobian matrix determination unit is used to determine the motion Jacobian matrix according to the foot end motion expression.

[0101] The equivalent passive spring-damper vibration reduction system construction unit is used to construct an equivalent passive spring-damper vibration reduction system according to the optimal spring stiffness, the optimal damping coefficient, the foot end motion expression and the motion Jacobian matrix.

[0102] The response tracking unit is used to perform response tracking according to an equivalent passive spring-damper vibration reduction system.

[0103] In order to execute the methods corresponding to the above embodiments to achieve the corresponding functions and technical effects, the present invention also provides a wheel-legged multi-modal unmanned platform vibration reduction control device, characterized in that it includes: at least one processor, at least one memory and computer program instructions stored in the memory, and when the computer program instructions are executed by the processor, the described method is implemented.

[0104] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0105] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A vibration reduction control method for a wheel-legged multi-modal unmanned platform, characterized in that: include: The driving module is arranged at the wheel-leg joint of the wheel-leg multi-modal unmanned platform; the driving module is used to control the torque output at the wheel-leg joint to achieve direct control of the hip joint movement and knee joint movement of the wheel-leg multi-modal unmanned platform; Taking the passive suspension vibration reduction system of the whole vehicle as an ideal reference model, an ideal virtual equivalent vibration reduction system of the wheel-legged multi-modal unmanned platform is constructed; the whole vehicle passive suspension vibration reduction system has the same size parameters, tire parameters, whole vehicle mass and tire mass as the wheel-legged multi-modal unmanned platform; The vehicle passive suspension vibration reduction system includes: spring stiffness and damping coefficient; According to the ideal virtual equivalent vibration reduction system, task requirements and corresponding key responses, an objective function is constructed with spring stiffness and damping coefficient as variables to be optimized; and the optimal spring stiffness and optimal damping coefficient are determined according to the objective function; Construct the kinematic model of the wheel-leg mechanism of the wheel-leg multimodal unmanned platform; and determine the foot end motion expression based on the kinematic model of the wheel-leg mechanism; Determine the motion Jacobian matrix based on the foot end motion expression; An equivalent passive spring-damper vibration reduction system is constructed based on the optimal spring stiffness, optimal damping coefficient, foot end motion expression and motion Jacobian matrix; Response tracking based on an equivalent passive spring-damper vibration reduction system; The equivalent passive spring-damper vibration reduction system is constructed according to the optimal spring stiffness, the optimal damping coefficient, the foot end motion expression and the motion Jacobian matrix, specifically including: [τ1,τ2]=J T (F x +F y ); Among them, J T is the transpose of the Jacobian matrix, F x =F k,x +F c,x is the longitudinal force at the foot end, is the longitudinal spring force, is the vertical spring force, are the optimal longitudinal spring stiffness and vertical spring stiffness, respectively. Δx and Δy are the longitudinal wheel-leg displacement and vertical wheel-leg displacement, respectively. y =F k,y +F c,y is the vertical force at the foot end, is the longitudinal damping force, is the vertical damping force, c x and c y are the longitudinal spring stiffness and the vertical spring stiffness, and is the longitudinal wheel-leg speed and vertical wheel-leg speed, τ1 and τ2 are the calculated joint torques; The joint torque τ1 and joint torque τ2 are distributed to the joint motor output, and an equivalent passive spring-damper vibration reduction system is constructed to complete the response tracking of the ideal whole vehicle passive suspension model, thereby realizing the design of the whole vehicle vibration reduction control system of the wheel-legged unmanned platform.

2. The vibration reduction control method for a wheel-legged multi-modal unmanned platform according to claim 1 is characterized in that: According to the ideal virtual equivalent vibration reduction system, task requirements and corresponding key responses, the objective function is constructed with spring stiffness and damping coefficient as variables to be optimized, specifically including: Among them, f(X)=λ1·f1+λ2·f2+...+λ n ·f n ,f1,f2,...,f n are different key responses, λ1,λ2,...,λ n is the weight value, which is determined according to the task requirements. X is the variable to be optimized. k and c represent the spring stiffness and damping coefficient of the front, rear, left and right wheels respectively. Subscripts 1, 2, 3 and 4 represent the left front wheel, right front wheel, left rear wheel and right rear wheel respectively. f(X) is the objective function. g(X) and h(X) are the equality constraints and inequality constraints respectively. Subscripts j and k represent the serial numbers of the actual constraint inequalities respectively.

3. The vibration reduction control method for a wheel-legged multi-modal unmanned platform according to claim 2 is characterized in that: The construction of the wheel-leg mechanism kinematic model of the wheel-leg multimodal unmanned platform; and determining the foot end motion expression according to the wheel-leg mechanism kinematic model specifically includes: According to the wheel-legged multimodal unmanned platform, the Denavit-Hartenberg convention method is used to establish the reference coordinate system of each joint; According to the reference coordinate system of each joint, the forward and inverse kinematics analysis of the two-link mechanism of the wheel-leg configuration of the wheel-leg multimodal unmanned platform is performed to obtain the foot end motion expression.

4. The vibration reduction control method for a wheel-legged multi-modal unmanned platform according to claim 3 is characterized in that: The foot end motion expression is: Where x, y are the foot end positions, is the foot velocity, a1 and a2 represent the thigh and calf lengths respectively, θ1 and θ2 represent the rotation angles of the hip joint in the coordinate system X0-Y0 and the knee joint in the coordinate system X1-Y1 respectively, and X0-Y0 and X1-Y1 represent the hip joint coordinate system and the knee joint coordinate system respectively.

5. The vibration reduction control method for a wheel-legged multi-modal unmanned platform according to claim 4 is characterized in that: Determining the motion Jacobian matrix according to the foot end motion expression specifically includes: Where J is the motion Jacobian matrix.

6. A wheel-legged multi-modal unmanned platform vibration reduction control system, which implements the wheel-legged multi-modal unmanned platform vibration reduction control method as described in any one of claims 1 to 5, characterized in that: include: A drive position determination unit is used to set a drive module at the wheel-leg joint of the wheel-leg multimodal unmanned platform; the drive module is used to control the torque output at the wheel-leg joint to achieve direct control of the hip joint movement and knee joint movement of the wheel-leg multimodal unmanned platform; An ideal virtual equivalent vibration reduction system building unit is used to build an ideal virtual equivalent vibration reduction system for a wheel-legged multi-modal unmanned platform by taking the whole vehicle passive suspension vibration reduction system as an ideal reference model; the whole vehicle passive suspension vibration reduction system has the same size parameters, tire parameters, whole vehicle mass and tire mass as the wheel-legged multi-modal unmanned platform; The vehicle passive suspension vibration reduction system includes: spring stiffness and damping coefficient; An objective function construction unit is used to construct an objective function based on an ideal virtual equivalent vibration reduction system, task requirements and corresponding key responses, with spring stiffness and damping coefficient as variables to be optimized; and determine an optimal spring stiffness and an optimal damping coefficient based on the objective function; The foot end motion expression determination unit is used to construct a wheel-leg mechanism kinematic model of the wheel-leg multimodal unmanned platform; and determine the foot end motion expression according to the wheel-leg mechanism kinematic model; A motion Jacobian matrix determining unit, used for determining the motion Jacobian matrix according to the foot end motion expression; An equivalent passive spring-damper vibration reduction system construction unit is used to construct an equivalent passive spring-damper vibration reduction system according to an optimal spring stiffness, an optimal damping coefficient, a foot end motion expression, and a motion Jacobian matrix; The response tracking unit is used to perform response tracking according to an equivalent passive spring-damper vibration reduction system.

7. A wheel-legged multi-modal unmanned platform vibration reduction control device, characterized in that: include: At least one processor, at least one memory and computer program instructions stored in the memory, when the computer program instructions are executed by the processor, implement the vibration reduction control method of the wheel-legged multi-modal unmanned platform as described in any one of claims 1-5.

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