Mobile double-arm robot self-adaptive cooperative anti-interference control method based on internal model

Abstract

The invention discloses a mobile double-arm robot self-adaptive cooperative anti-interference control method based on an internal model, and relates to the technical field of manipulators. The method comprises the following steps: 1, regarding the mobile double-arm robot as a whole, and establishing a kinematic model of the mobile double-arm robot by adopting a relative Jacobian matrix method; 2, aiming at the interference of unknown noise, designing to obtain a self-adaptive compensator for suppressing the noise; 3, based on the pose error of the self-adaptive compensator and the end effector of the mobile double-arm robot, obtaining a mobile double-arm robot self-adaptive collaborative anti-interference controller based on the internal model; step 4, in combination with the kinematic model of the mobile double-arm robot, transmitting a calculation result of the mobile double-arm robot adaptive cooperative anti-interference controller to a lower computer, and controlling the mobile double-arm robot; by means of the mobile double-arm robot self-adaptive cooperative anti-interference controller based on the internal model, unknown noise interference can be effectively dealt with, and the good cooperative capacity is kept.

Description

Technical Field

[0001] The present invention relates to the technical field of manipulators, and in particular to an internal model-based adaptive collaborative anti-disturbance control method for a mobile dual-arm robot. Background Art

[0002] With the advancement of robotics technology, mobile dual-arm robots are increasingly being used in a variety of fields, including manufacturing and service, thanks to their flexible maneuverability and powerful collaborative capabilities. When performing tasks, mobile dual-arm robots typically treat each arm and mobile platform as independent units and control them separately. While this approach simplifies the design and implementation of control methods, it also limits the coordination efficiency between these components, thereby affecting overall performance.

[0003] In actual operating environments, mobile dual-arm robots often face a variety of unpredictable noise interference, including but not limited to mechanical vibration, electromagnetic interference, temperature changes, and uneven ground conditions. These unknown noises not only affect the control accuracy of a single robotic arm or mobile platform, but may also disrupt the coordination between the various parts of the entire system, resulting in motion deviations, reduced execution efficiency, and even mission failure. Currently widely used control methods are often designed based on idealized models, usually assuming that the working environment is known and relatively stable. Therefore, they are not flexible enough when dealing with disturbances caused by external uncertainties, and it is difficult to effectively compensate for errors caused by unknown noise. This makes existing technologies have certain limitations when facing complex situations in the real world.

[0004] Therefore, the inability of mobile dual-arm robots to effectively cope with unknown noise interference and maintain good coordination capabilities has become a technical problem that needs to be solved urgently. Summary of the Invention

[0005] The present invention provides an adaptive collaborative anti-disturbance control method for a mobile dual-arm robot based on an internal model, which solves the technical problem of how to effectively cope with unknown noise interference and maintain good collaborative ability.

[0006] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0007] An adaptive cooperative anti-disturbance control method for a mobile dual-arm robot based on an internal model comprises the following steps:

[0008] Step 1: Consider the mobile dual-arm robot as a whole and use the relative Jacobian matrix method to establish the kinematic model of the mobile dual-arm machine;

[0009] Step 2: Design an adaptive compensator to suppress the unknown noise interference;

[0010] Step 3: Based on the pose error between the adaptive compensator and the end effector of the mobile dual-arm robot, an adaptive cooperative disturbance rejection controller for the mobile dual-arm robot based on the internal model is obtained;

[0011]

[0012] In formula 3, For J R The pseudo-inverse matrix, σ(t)=f(x dm )-r(t) is the pose error of the end effector of the mobile dual-arm robot, f(·) is the nonlinear mapping function; the control parameters must satisfy a>0, μ>0;

[0013] Step 4: Combined with the kinematic model of the mobile dual-arm machine, the calculation results of the adaptive cooperative anti-disturbance controller of the mobile dual-arm robot are transmitted to the lower computer to control the mobile dual-arm robot.

[0014] A further technical solution is: in step 1, the kinematic model of the mobile dual-arm robot is:

[0015]

[0016] In formula 1, J R (x dm (t)) is the relative Jacobian matrix of the mobile dual-arm robot, and the vector of the joint angle and wheel angle of the mobile dual-arm robot is represented by x dm (t)=[q1,...,q n ,w1,...w m ] T ,q n is the nth joint angle, w m is the mth wheel angle; is the vector of joint velocity and wheel velocity of the mobile dual-arm robot, is the angular velocity of the nth joint, is the angular velocity of the mth wheel, the arms of the mobile dual-arm robot contain n joints, and the mobile platform of the mobile dual-arm robot has m wheels; h(t) is the unknown noise, r(t) is the expected pose vector of the end effector of the mobile dual-arm robot, is the desired velocity vector of the end effector of the mobile dual-arm robot, obtained by taking the derivative of r(t) with respect to t, where t represents time.

[0017] A further technical solution is that: in step 2, the adaptive compensator is,

[0018]

[0019] In formula 2, By taking the derivative of h(t) with respect to t, we can get zj (t) is used to suppress h j (t) Interference signal, s j (t) by h j (t) Taking the derivative with respect to t, we can get By s j By taking the derivative of (t) with respect to t, we can obtain that the noise compensator parameters should satisfy k≥3.

[0020] A further technical solution is that: in step 2, the noise compensator parameter k=4, and the unknown noise is split into four harmonic noise signals.

[0021] A further technical solution is that in step 2, the adaptive compensator learns the characteristics of these harmonic noise signals in real time and generates corresponding compensation signals.

[0022] A further technical solution is that the mobile dual-arm robot includes a four-wheel mobile chassis, a first robotic arm and a second robotic arm, and the first robotic arm and the second robotic arm are both fixedly connected to the four-wheel mobile chassis.

[0023] A further technical solution is that operating tools are installed at the ends of the first robotic arm and the second robotic arm.

[0024] A further technical solution is that the first robotic arm and the second robotic arm are both three-axis robotic arms.

[0025] The beneficial effects of adopting the above technical solution are:

[0026] An internal model-based adaptive collaborative disturbance rejection control method for a mobile dual-arm robot includes the following steps: Step 1: Considering the mobile dual-arm robot as a whole, a relative Jacobian matrix method is used to establish a kinematic model of the mobile dual-arm robot; Step 2: Designing an adaptive compensator to suppress the noise in response to unknown noise interference; Step 3: Based on the pose error between the adaptive compensator and the end effector of the mobile dual-arm robot, an internal model-based adaptive collaborative disturbance rejection controller for the mobile dual-arm robot is obtained; Step 4: Based on the kinematic model of the mobile dual-arm robot, the calculation results of the mobile dual-arm robot adaptive collaborative disturbance rejection controller are transmitted to a lower computer to control the mobile dual-arm robot. This internal model-based adaptive collaborative disturbance rejection controller for the mobile dual-arm robot can effectively cope with unknown noise interference and maintain good collaborative capabilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural diagram of the mobile dual-arm robot in this application;

[0028] Figure 2 It is a flow chart of the control method in this application.

[0029] Among them: 1 four-wheel mobile chassis, 2 first robotic arm, 3 second robotic arm. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0031] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0032] like Figure 2 As shown, the present invention discloses an adaptive collaborative anti-disturbance control method for a mobile dual-arm robot based on an internal model, comprising the following steps.

[0033] Step 1: Consider the mobile dual-arm robot as a whole and use the relative Jacobian matrix method to establish the kinematic model of the mobile dual-arm machine.

[0034] like Figure 1 As shown, the robot mainly includes a four-wheel mobile chassis 1, two three-axis robotic arms and operating tools installed at the ends of the robotic arms. The two three-axis robotic arms are respectively a first robotic arm 2 and a second robotic arm 3.

[0035] The relative Jacobian matrix is ​​derived by performing coordinate transformation on the Jacobian matrices of the first robotic arm 2, the second robotic arm 3 and the four-wheeled mobile chassis 1, where the four-wheeled mobile chassis 1 is the mobile platform.

[0036] First, the joint coordinate system of each robotic arm is determined, and the DH parameters are obtained to represent the relationship between adjacent links. The relative Jacobian matrix method is used to calculate the transformation matrix from the base to the end effector to obtain the forward kinematic model of each robotic arm. For the mobile platform, the position and orientation of the contact points between its four wheels and the ground, as well as possible non-holonomic constraints, are considered. Finally, the models of the mobile platform and the two robotic arms are combined to form a comprehensive kinematic model of the entire system.

[0037] The kinematic model of the mobile dual-arm robot is designed taking into account the influence of noise:

[0038]

[0039] In formula 1, J R (x dm (t)) is the relative Jacobian matrix of the mobile dual-arm robot, and the vector of the joint angle and wheel angle of the mobile dual-arm robot is represented by x dm (t)=[q1,...,q n ,w1,...w m ] T ,q n is the nth joint angle, w m is the mth wheel angle; is the vector of joint velocity and wheel velocity of the mobile dual-arm robot, is the angular velocity of the nth joint, is the angular velocity of the mth wheel, the arms of the mobile dual-arm robot contain n joints, and the mobile platform of the mobile dual-arm robot has m wheels; h(t) is the unknown noise, r(t) is the expected pose vector of the end effector of the mobile dual-arm robot, is the desired velocity vector of the end effector of the mobile dual-arm robot, obtained by taking the derivative of r(t) with respect to t, where t represents time.

[0040] Step 2: Design an adaptive compensator to suppress the unknown noise interference.

[0041] In actual operation, the presence of various unknown noises in the environment will affect the control accuracy of the mobile dual-arm robot. Through Fourier transform, the unknown noise h(t) can be decomposed into multiple different harmonic signals. According to the internal model principle, the adaptive compensator for suppressing noise is designed as follows:

[0042]

[0043] In formula 2, By taking the derivative of h(t) with respect to t, we can get z j (t) is used to suppress h j (t) Interference signal, s j (t) by h j (t) Taking the derivative with respect to t, we can get By s j By taking the derivative of (t) with respect to t, we can obtain that the noise compensator parameters should satisfy k≥3.

[0044] In this embodiment, the noise compensator parameter k is set to 4, and the unknown noise is split into four different harmonic noise signals. To suppress the noise, the adaptive compensator learns the characteristics of these harmonic noise signals in real time and generates corresponding compensation signals.

[0045] The adaptive compensator for suppressing noise can adaptively simulate unknown noise without any noise information, thereby achieving the effect of suppressing noise.

[0046] Step 3: In order to meet the requirements of the mobile dual-arm robot in collaborative motion control, the adaptive compensator and the posture error of the mobile dual-arm robot end effector are introduced to obtain an adaptive collaborative anti-disturbance controller for the mobile dual-arm robot based on the internal model.

[0047] The adaptive cooperative disturbance rejection controller of the mobile dual-arm robot based on the internal model is designed as follows:

[0048]

[0049] In formula 3, For J R The pseudo-inverse matrix, σ(t)=f(x dm )-r(t) is the pose error of the end effector of the mobile dual-arm robot, f(·) is the nonlinear mapping function; the control parameters must satisfy a>0, μ>0.

[0050] In this embodiment, combined with the structure of the mobile dual-arm robot in the embodiment, an adaptive cooperative disturbance rejection controller for the mobile dual-arm robot based on an internal model is specifically designed as follows:

[0051]

[0052] The arms of the mobile dual-arm robot have six joints and its mobile platform has four wheels. The vectors of its joint velocities and wheel velocities are defined as The control parameters are set as a=1,μ=1. In the proposed adaptive cooperative disturbance rejection controller for mobile dual-arm robots based on internal model, the The dynamic equations of the mobile dual-arm robot are solved in real time to calculate the joint angles and wheel angles; other dynamic equations are calculated in real time. and ensure This suppresses noise interference.

[0053] In the kinematic model of the mobile dual-arm robot, the adaptive compensator and the posture error of its end effector are introduced, so that the proposed cooperative anti-disturbance controller can effectively suppress the interference of noise on the mobile dual-arm robot.

[0054] Step 4: Combined with the established kinematic model of the mobile dual-arm machine, the calculation results of the adaptive collaborative anti-disturbance controller of the mobile dual-arm robot are transmitted to the lower computer to control the mobile dual-arm robot to complete the desired collaborative control task.

[0055] The joint and wheel velocities of the mobile dual-arm robot are calculated using an internal model-based adaptive collaborative anti-disturbance control method. The results are transmitted to a slave controller. The slave controller configures the mobile dual-arm robot with an efficient drive algorithm and multiple joint and wheel drive modules. This drive algorithm converts the calculated results into detailed drive instructions to control each joint and wheel of the mobile dual-arm robot, ensuring that the robot can execute the intended collaborative control task despite interference from harmonic noise.

[0056] The lower-level controller is equipped with a set of drive control algorithms and several drive units. Its function is to convert the results of the collaborative motion control method into specific drive commands. In this way, the controller can precisely control the wheels and joints of the mobile dual-arm robot to achieve the control according to the established collaborative motion task.

[0057] Compared with the existing technical solutions, the technical solution of this application has the following advantages:

[0058] To address the problem of unknown noise interference affecting the control accuracy of a mobile dual-arm robot in collaborative motion, this application designs an adaptive noise compensator and integrates it and the posture error of the mobile dual-arm robot's end effector into the control scheme to eliminate noise.

[0059] This application effectively overcomes the shortcomings of existing methods by defining a mathematical model for the collaborative operation of mobile dual-arm robots. Based on the internal model principle and combined with an adaptive unknown noise compensator, this model can offset external noise interference in real time, improving the accuracy and reliability of mobile dual-arm robots when performing collaborative tasks in complex situations. This model provides strong support for widespread application in various fields, including manufacturing and services.

[0060] The collaborative anti-disturbance control method designed in this application has good real-time and robustness, and can ensure that the mobile dual-arm robot can efficiently and stably complete the desired collaborative control tasks in complex environments, showing high practical value.

[0061] Compared with the above embodiment, the first robotic arm and the second robotic arm can also be a four-axis robotic arm, a five-axis robotic arm or a six-axis robotic arm, which can be selected according to actual use needs and are all within the scope of protection of this application.

Claims

1. An adaptive cooperative disturbance rejection control method for a mobile dual-arm robot based on an internal model, characterized by: The following steps are included: Step 1: Consider the mobile dual-arm robot as a whole and use the relative Jacobian matrix method to establish the kinematic model of the mobile dual-arm machine; Step 2: Design an adaptive compensator to suppress the unknown noise interference; Step 3: Based on the pose error between the adaptive compensator and the end effector of the mobile dual-arm robot, an adaptive cooperative disturbance rejection controller for the mobile dual-arm robot based on the internal model is obtained; In formula 3, For J R The pseudo-inverse matrix, σ(t)=f(x dm )-r(t) is the pose error of the end effector of the mobile dual-arm robot, f(·) is the nonlinear mapping function; the control parameters must satisfy a>0, μ>0; Step 4: Combined with the kinematic model of the mobile dual-arm machine, the calculation results of the adaptive cooperative anti-disturbance controller of the mobile dual-arm robot are transmitted to the lower computer to control the mobile dual-arm robot.

2. The method for adaptive cooperative disturbance rejection control of a mobile dual-arm robot based on an internal model according to claim 1, characterized in that: In step 1, the kinematic model of the mobile dual-arm robot is: In formula 1, J R (x dm (t)) is the relative Jacobian matrix of the mobile dual-arm robot, and the vector of the joint angle and wheel angle of the mobile dual-arm robot is represented by x dm (t)=[q1,...,q n ,w1,...w m ] T ,q n is the nth joint angle, w m is the mth wheel angle; is the vector of joint velocity and wheel velocity of the mobile dual-arm robot, is the angular velocity of the nth joint, is the angular velocity of the mth wheel, the arms of the mobile dual-arm robot contain n joints, and the mobile platform of the mobile dual-arm robot has m wheels; h(t) is the unknown noise, r(t) is the expected pose vector of the end effector of the mobile dual-arm robot, is the desired velocity vector of the end effector of the mobile dual-arm robot, obtained by taking the derivative of r(t) with respect to t, where t represents time.

3. The method for adaptive cooperative disturbance rejection control of a mobile dual-arm robot based on an internal model according to claim 1, characterized in that: In step 2, the adaptive compensator is: In formula 2, By taking the derivative of h(t) with respect to t, we can get z j (t) is used to suppress h j (t) Interference signal, s j (t) by h j (t) Taking the derivative with respect to t, we can get By s j By taking the derivative of (t) with respect to t, we can obtain that the noise compensator parameters should satisfy k≥3.

4. The method for adaptive cooperative disturbance rejection control of a mobile dual-arm robot based on an internal model according to claim 3, characterized in that: In step 2, the noise compensator parameter k=4, which splits the unknown noise into four harmonic noise signals.

5. The method for adaptive cooperative disturbance rejection control of a mobile dual-arm robot based on an internal model according to claim 4, characterized in that: In step 2, the adaptive compensator learns the characteristics of these harmonic noise signals in real time and generates corresponding compensation signals.

6. The method for adaptive cooperative disturbance rejection control of a mobile dual-arm robot based on an internal model according to claim 1, characterized in that: The mobile dual-arm robot comprises a four-wheel mobile chassis (1), a first mechanical arm (2) and a second mechanical arm (3), wherein the first mechanical arm (2) and the second mechanical arm (3) are both fixedly connected to the four-wheel mobile chassis (1).

7. The method for adaptive cooperative disturbance rejection control of a mobile dual-arm robot based on an internal model according to claim 6, characterized in that: Operating tools are installed at the ends of the first robotic arm (2) and the second robotic arm (3).

8. The method for adaptive coordinated disturbance rejection control of a mobile dual-arm robot based on an internal model according to claim 6, characterized in that: The first robotic arm (2) and the second robotic arm (3) are both three-axis robotic arms.

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