Compliant control method and device of robot and electronic equipment

Abstract

The application discloses a kind of robot compliant control method, device and electronic equipment, it is related to robot compliant control technical field, comprising: obtaining Cartesian planning position, joint angle feedback position and Cartesian feedback position;Utilize target compliant controller, Cartesian planning position and Cartesian feedback position and joint angle feedback position are handled, and joint output torque is obtained;Utilize joint output torque to control robot movement;Target compliant controller is to robot for dynamics modeling and second-order system dynamic characteristic modeling to obtain original compliant controller, and original compliant controller is simplified to obtain;According to the virtual wall numerical value of preestablished and Cartesian feedback position, and preestablished parameter, adjust the stiffness parameter and damping parameter of second-order system in target compliant controller.The influence of the accuracy of external torque on the control accuracy of robot movement can be eliminated.The influence of robot singularity on motion control can be avoided.The virtual wall function can be easily realized.

Description

Technical Field

[0001] This invention relates to the field of robot compliance control technology, and more particularly to a robot compliance control method, apparatus, and electronic device. Background Technology

[0002] With technological advancements and the diversification of working environments, the demand for robots is becoming increasingly widespread. Compliant control of robots has also garnered significant attention. Compliant control is a technique that controls the relationship between force and position, enabling robots to adapt to changes in the forces acting on their work environment.

[0003] In compliant control techniques, force sensors are typically used to acquire the external torque acting on the robot, and this external torque is then used to determine the joint output torque. This joint output torque is used to control the robot's movement. The control process is generally affected by robot singularities.

[0004] However, in the above methods, the force sensor is susceptible to the influence of ambient temperature, which means that the accuracy of the obtained external torque needs to be further improved, thus affecting the motion control precision of the robot. Moreover, the existence of robot singularities can easily affect the reliability of robot control. Summary of the Invention

[0005] This invention provides a compliant control method, device, and electronic device for robots to address the problems in related technologies where force sensors are easily affected by ambient temperature, resulting in the need to further improve the accuracy of the external torque obtained, which in turn requires further improvement in the motion control precision of the robot; and the existence of robot singularities can easily affect the reliability of robot control.

[0006] According to one aspect of the present invention, a compliant control method for a robot is provided, comprising:

[0007] Obtain the Cartesian planning position obtained from trajectory planning, and use the position sensor to obtain the joint angle feedback position and Cartesian feedback position;

[0008] Using a target compliance controller, the Cartesian planned position, the Cartesian feedback position, and the joint angle feedback position are processed to obtain the joint output torque;

[0009] The robot's movement is controlled by the torque output from the joints.

[0010] The target compliant controller is obtained by performing dynamic modeling and second-order system dynamic characteristic modeling on the robot to obtain the original compliant controller, and then simplifying the original compliant controller; according to the preset virtual wall value, the Cartesian feedback position, and preset parameters, the stiffness parameters and damping parameters of the second-order system in the target compliant controller are adjusted.

[0011] According to another aspect of the present invention, a compliant control device for a robot is provided, comprising:

[0012] The acquisition unit is used to acquire the Cartesian planning position obtained from trajectory planning, and to acquire the joint angle feedback position and Cartesian feedback position using the position sensor;

[0013] A compliance control unit is used to process the Cartesian planned position, the Cartesian feedback position, and the joint angle feedback position using a target compliance controller to obtain the joint output torque;

[0014] The compliant control unit is also used to control the robot's movement by utilizing the joint output torque;

[0015] The target compliant controller is obtained by performing dynamic modeling and second-order system dynamic characteristic modeling on the robot to obtain the original compliant controller, and then simplifying the original compliant controller; according to the preset virtual wall value, the Cartesian feedback position, and preset parameters, the stiffness parameters and damping parameters of the second-order system in the target compliant controller are adjusted.

[0016] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0017] At least one processor; and

[0018] A memory communicatively connected to the at least one processor; wherein,

[0019] The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the compliant control method for a robot according to any embodiment of the present invention.

[0020] According to another aspect of the present invention, a computer-readable storage medium is provided, the computer-readable storage medium storing computer instructions for causing a processor to execute and implement the compliant control method of a robot according to any embodiment of the present invention.

[0021] The technical solution of this invention simplifies the original compliant controller to obtain a target compliant controller, which is then used to control the robot's motion. This eliminates the influence of the accuracy of external torque on the robot's motion control accuracy and enhances the reliability of robot control. Furthermore, the stiffness and damping parameters of the second-order system in the target compliant controller can be adjusted according to preset virtual wall values, Cartesian feedback positions, and preset parameters, thus easily implementing the robot's virtual wall function.

[0022] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a flowchart of a compliant control method for a robot according to Embodiment 1 of the present invention;

[0025] Figure 2 This is a flowchart of a compliant control method for a robot according to Embodiment 2 of the present invention;

[0026] Figure 3 This is a demonstration diagram of the dynamic characteristics of a second-order robot system according to Embodiment 2 of the present invention;

[0027] Figure 4 This is a demonstration diagram of a robot virtual wall function provided according to Embodiment 2 of the present invention;

[0028] Figure 5 This is a schematic diagram of a compliant control principle for a robot according to Embodiment 2 of the present invention;

[0029] Figure 6 This is a schematic diagram of the structure of a compliant control device for a robot according to Embodiment 3 of the present invention;

[0030] Figure 7 This is a schematic diagram of the structure of an electronic device that implements the compliant control method for a robot according to an embodiment of the present invention. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0032] It should be noted that the terms "target," "original," etc., used in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0033] Example 1

[0034] Figure 1 This is a flowchart of a compliant control method for a robot according to Embodiment 1 of the present invention. This embodiment is applicable to compliant control of robots, wherein the robot can be an industrial robot (e.g., a six-axis robot) or a collaborative robot. The method can be executed by an electronic device that can be configured within the robot. Figure 1 As shown, the method includes:

[0035] Step 101: Obtain the Cartesian planning position obtained from trajectory planning, and use the position sensor to obtain the joint angle feedback position and Cartesian feedback position.

[0036] Among them, the Cartesian planning position refers to the position of the robot in the Cartesian coordinate system obtained by trajectory planning.

[0037] The joint angle feedback position refers to the position of each joint of the robot obtained using position sensors. The joint angle feedback position can be calculated using forward kinematics to obtain the feedback position of the robot's end effector in the Cartesian coordinate system, i.e., the Cartesian feedback position.

[0038] Specifically, trajectory planning can be used to obtain the Cartesian program position. Then, the Cartesian program position obtained from the trajectory planning can be retrieved.

[0039] Specifically, the joint angle feedback position can be obtained using a position sensor. The Cartesian feedback position can then be calculated from this joint angle feedback position.

[0040] Step 102: Using the target compliant controller, the Cartesian planning position, Cartesian feedback position, and joint angle feedback position are processed to obtain the joint output torque. The target compliant controller is obtained by performing dynamic modeling and second-order system dynamic characteristic modeling on the robot to obtain the original compliant controller, and then simplifying the original compliant controller. According to the preset virtual wall values, Cartesian feedback positions, and preset parameters, the stiffness parameters and damping parameters of the second-order system in the target compliant controller are adjusted.

[0041] Specifically, dynamic modeling and second-order system dynamic characteristic modeling of the robot can be performed to obtain the original compliant controller. Then, the original compliant controller can be simplified to obtain the target compliant controller. This target compliant controller is then used to perform compliant control of the robot, eliminating the influence of the accuracy of external torques on the robot's motion control accuracy and enhancing the reliability of robot control.

[0042] In one possible implementation, the target compliant controller is specifically obtained by simplifying it by removing the external torque term and the inverse of the Jacobian matrix from the original compliant controller.

[0043] Specifically, removing the external torque term eliminates the need for force sensors to collect external torque, thus removing the impact of the accuracy of the external torque on the accuracy of robot motion control. Removing the inverse of the Jacobian matrix avoids the influence of robot singularities on motion control, thereby enhancing the reliability of robot control.

[0044] The preset virtual wall values ​​are pre-set according to actual needs. These preset virtual wall values ​​can represent a three-dimensional space.

[0045] Among them, the preset parameters are parameters that are set in advance according to the actual situation.

[0046] Specifically, the positional relationship between the Cartesian feedback position and the three-dimensional space represented by the preset virtual wall value can be determined first (whether the Cartesian feedback position is inside or outside the three-dimensional space represented by the preset virtual wall value). Then, based on this positional relationship and the preset parameters, the stiffness target value and damping target value can be determined. Then, the stiffness parameter of the second-order system in the target compliance controller is adjusted to the stiffness target value, and the damping parameter of the second-order system in the target compliance controller is adjusted to the damping target value.

[0047] Specifically, the stiffness and damping parameters of the second-order system in the target compliant controller can be adjusted according to the preset virtual wall values, Cartesian feedback position, and preset parameters to achieve the robot's virtual wall function in a simple way.

[0048] Then, the obtained Cartesian planning position, Cartesian feedback position, and joint angle feedback position can be input into the target compliance controller, which outputs the joint output torque.

[0049] Step 103: Control the robot's movement using the joint output torque.

[0050] Specifically, an output torque command can be generated based on the joint output torque. This output torque command is then transmitted to the driver via a torque interface, and the driver uses this output torque command to control the robot's movement.

[0051] Specifically, the technical solution provided in this embodiment simplifies the original compliant controller to obtain a target compliant controller, which is then used to control the robot's motion. This eliminates the influence of the accuracy of external torque on the robot's motion control accuracy and enhances the reliability of robot control. Furthermore, the stiffness and damping parameters of the second-order system in the target compliant controller can be adjusted according to preset virtual wall values, Cartesian feedback positions, and preset parameters to easily implement the robot's virtual wall function.

[0052] Example 2

[0053] Figure 2 This is a flowchart of a robot compliant control method according to Embodiment 2 of the present invention. This embodiment refines the setting of the stiffness parameters of the second-order system in the target compliant controller in Embodiment 1 above, so as to further realize the robot's follow-up control or floating control. Figure 2 As shown, the method includes:

[0054] Step 201: Obtain the Cartesian planning position obtained from trajectory planning, and use the position sensor to obtain the joint angle feedback position and Cartesian feedback position.

[0055] Specifically, the principles and implementation methods of step 201 are similar to those of step 101, and will not be repeated here.

[0056] Step 202: Based on the preset virtual wall values, Cartesian feedback position, and preset parameters, adjust the stiffness and damping parameters of the second-order system in the target compliant controller. The target compliant controller is obtained by simplifying the original compliant controller, which is derived from dynamic modeling of the robot and dynamic characteristic modeling of the second-order system. The preset parameters include one or more combinations of the following: the maximum value of the preset second-order system stiffness parameter, the maximum value of the preset second-order system damping parameter, the preset second-order system stiffness parameter value, or the preset second-order system damping parameter value; wherein the preset second-order system stiffness parameter value is less than the maximum value of the preset second-order system stiffness parameter; and the preset second-order system damping parameter value is less than the maximum value of the preset second-order system damping parameter.

[0057] The preset virtual wall values ​​are pre-set according to actual needs. These preset virtual wall values ​​can represent a three-dimensional space.

[0058] Among them, the preset parameters are parameters that are set in advance according to the actual situation.

[0059] Specifically, the positional relationship between the Cartesian feedback position and the three-dimensional space represented by the preset virtual wall value can be determined first (whether the Cartesian feedback position is inside or outside the three-dimensional space represented by the preset virtual wall value). Then, based on this positional relationship and the preset parameters, the target stiffness value and the target damping value can be determined.

[0060] The maximum value of the preset stiffness parameter of the second-order system is the value of the stiffness parameter preset according to the actual situation, and the value of the preset stiffness parameter of the second-order system is less than the maximum value of the preset stiffness parameter of the second-order system.

[0061] The maximum value of the preset damping parameter of the second-order system is the value of the damping parameter preset according to the actual situation, and the preset damping parameter value of the second-order system is less than the maximum value of the preset damping parameter of the second-order system.

[0062] Specifically, taking a six-axis robot as an example, the target values ​​for stiffness and damping can be determined using the following formulas.

[0063]

[0064]

[0065] Where K represents the target stiffness value; K set K represents the preset stiffness parameter value of the second-order system. max B represents the maximum value of the preset stiffness parameter of the second-order system; B represents the target damping value; B set B represents the preset damping parameter value of the second-order system; max This represents the maximum value of the preset damping parameter of the second-order system; t represents time; C is a parameter value preset according to actual conditions; x fb Indicates the Cartesian feedback position; x wall Indicates the preset virtual wall value; x fb >x wall This indicates that the Cartesian feedback location is outside the three-dimensional space represented by the preset virtual wall values; x fb <x wallThis indicates that the Cartesian feedback position is within the three-dimensional space represented by the preset virtual wall value.

[0066] Then, the stiffness parameters of the second-order system in the target compliant controller can be adjusted to the target stiffness value, and the damping parameters of the second-order system in the target compliant controller can be adjusted to the target damping value. Then, by using the parameter-adjusted target compliant controller to perform compliant control of the robot, a virtual wall function can be achieved. That is, when the Cartesian feedback position is within the three-dimensional space represented by the preset virtual wall value, the robot is subjected to compliant control; when the Cartesian feedback position is outside the three-dimensional space represented by the preset virtual wall value, the robot is subjected to non-compliant control (such as pure position control). In this way, flexible control of the robot can be achieved while protecting user safety.

[0067] In one possible implementation, in response to a user's servo mode switching operation, the stiffness parameter of the second-order system in the target compliant controller is adjusted to zero to achieve servo control of the robot.

[0068] Among them, follow-up control refers to the ability of a robot to move under the action of external forces, and to remain stable in its current position without moving when the external forces are lost.

[0069] Specifically, a follow-up mode conversion button can also be set. This button can be installed on the robot. When the Cartesian feedback position is within the three-dimensional space represented by the preset virtual wall value, the user can press the follow-up mode conversion button to achieve follow-up control of the robot as needed. Specifically, the electronic device can respond to the user's press of the follow-up mode conversion button and adjust the stiffness parameter of the second-order system in the target compliant controller to zero to achieve follow-up control of the robot.

[0070] Furthermore, servo control can be further developed into a drag-and-drop teaching process.

[0071] In one possible implementation, in response to a user's floating mode switching operation, the stiffness parameters of the second-order system in the target compliant controller are adjusted to a preset floating value for floating control of the robot.

[0072] The preset floating value is a pre-set value that can be obtained through experimental debugging.

[0073] Among them, floating control refers to the ability of a robot to move under the action of external forces and return to the position before the external force was applied when the external force is lost.

[0074] Specifically, a floating mode conversion button can be set. This button can be installed on the robot. When the Cartesian feedback position is within the three-dimensional space represented by the preset virtual wall value, the user can press the floating mode conversion button to control the robot's floating operation as needed. Specifically, the electronic device can respond to the user's press of the floating mode conversion button and adjust the stiffness parameters of the second-order system in the target compliant controller to the preset floating value to achieve floating control of the robot.

[0075] Furthermore, float control can be further developed for processes such as soft float, grinding, or polishing. This increases the versatility of the compliance control method.

[0076] Specifically, the solution provided in this embodiment can easily achieve servo control or floating control of the robot by adjusting the stiffness parameters of the second-order system in the target compliant controller.

[0077] Step 203: Using the target compliance controller, process the Cartesian planned position, Cartesian feedback position, and joint angle feedback position to obtain the joint output torque.

[0078] Specifically, the obtained Cartesian planning position, Cartesian feedback position, and joint angle feedback position can be input into the target compliance controller, which then outputs the joint output torque.

[0079] Step 204: Control the robot's movement using the joint output torque.

[0080] Specifically, the principle and implementation of step 204 are similar to those of step 103, and will not be repeated here.

[0081] Specifically, taking the compliant control of a six-axis robot as an example, this embodiment will elaborate on the compliant control method provided.

[0082] First, a dynamic model of the robot needs to be established. By performing a force analysis on the robot and applying the Newton-Euler equations, the dynamic model can be obtained, as shown in the following formula:

[0083]

[0084] in, q represents the joint angle feedback acceleration, joint angle feedback velocity, and joint angle feedback position, respectively. Represents inertial force; Represents the Coriolis force; g(q) is the gravity term; τ m This is the joint output torque. If we consider the internal frictional force τ of the robot... fric The external force (i.e., the external torque term) F acting on the robot extIf flexible joints are not considered, the complete dynamic model can be represented as follows:

[0085]

[0086] Where J represents the Jacobian matrix; J T This represents the transpose of J.

[0087] Then, a second-order system dynamic characteristic modeling analysis is performed on the robot. Specifically, based on the impedance control principle, a second-order system dynamic characteristic model is performed on the robot's end effector, as shown in the following equation:

[0088]

[0089] Where M is the inertial parameter of the second-order system; B is the damping parameter of the second-order system; and K is the stiffness parameter of the second-order system. These represent the Cartesian programming velocity and Cartesian programming acceleration obtained through trajectory planning, respectively. These represent the Cartesian feedback velocity and Cartesian feedback acceleration of the robot obtained through the position sensor, respectively; x d x fb These represent the Cartesian planned position obtained through trajectory planning, and the Cartesian feedback position of the robot obtained through the position sensor, respectively. Specifically, a demonstration diagram of the robot's second-order system dynamic characteristics is shown below. Figure 3 As shown.

[0090] Based on the above analysis, the original compliant controller in Cartesian coordinates can be designed as follows:

[0091]

[0092] Where, τ m Indicates the output torque of the joint; q represents the joint angle feedback acceleration, joint angle feedback velocity, and joint angle feedback position, respectively; H(q) represents the inertia matrix; J represents the Jacobian matrix; J -1 denoted by ; M is the inverse of the Jacobian matrix; B is the damping parameter of the second-order system; K is the stiffness parameter of the second-order system. These represent the Cartesian programming velocity and Cartesian programming acceleration obtained through trajectory planning, respectively. These represent the Cartesian feedback velocity and Cartesian feedback acceleration of the robot obtained through the position sensor, respectively; x d x fb F represents the Cartesian planned position obtained through trajectory planning, and the Cartesian feedback position of the robot obtained through the position sensor, respectively; extThis represents the external force acting on the robot (i.e., the external torque term); Represents the Coriolis force; g(q) is the gravity term; τ fric This represents the internal friction force of the robot.

[0093] The original compliant controller has the following drawbacks: (1) It requires online solution of the inverse of the Jacobian matrix, which is affected by the robot's singularity during operation; (2) It requires accurate measurement of the external force at the end of the robot actuator, which is generally obtained through a force sensor. The force sensor is easily affected by the ambient temperature, which makes the accuracy of the obtained external torque need to be further improved, thus affecting the motion control accuracy of the robot. Moreover, the force sensor is relatively expensive, with a large equipment investment and low cost-effectiveness. In view of the above drawbacks, the original compliant controller is simplified to obtain the target compliant controller:

[0094]

[0095] Where, τ m Indicates the output torque of the joint; q represents the joint angle feedback velocity and the joint angle feedback position, respectively; J represents the Jacobian matrix; J T Let J represent the transpose of J; B is the damping parameter of the second-order system; K is the stiffness parameter of the second-order system. This represents the Cartesian feedback velocity of the robot obtained through the position sensor; x d x fb These represent the Cartesian planned position obtained through trajectory planning and the Cartesian feedback position of the robot obtained through the position sensor, respectively. Represents the Coriolis force; g(q) is the gravity term; τ fric This represents the internal friction force of the robot. The Cartesian planned position can be obtained through trajectory planning; the joint angle feedback position can be obtained using position sensors; and the joint angle feedback velocity, Cartesian feedback position, and Cartesian feedback velocity can be calculated from the joint angle feedback position. The joint angle feedback velocity refers to the velocity of each joint of the robot; the Cartesian feedback velocity refers to the velocity of the robot's end effector in the Cartesian coordinate system.

[0096] The target compliance controller has the following advantages: (1) It simplifies the tedious differential calculation, avoids the influence of high-frequency interference differential, and is simple to design. The compliance control can be adjusted by simply adjusting the stiffness parameter and the damping parameter; (2) It does not require online solving of the inverse matrix of the Jacobian matrix and is not affected by the robot singularity; (3) It eliminates the external force part, improves the cost performance, and does not require the use of force sensors to collect external torque, thus eliminating the influence of the accuracy of external torque on the accuracy of robot motion control.

[0097] Furthermore, the target compliance controller can be further refined, as shown below:

[0098] (1) The rotational motion attitude difference requires special handling. Here, quaternions are used to calculate the attitude difference between the command and the feedback:

[0099] q e =q fb -1 q d

[0100] Where, q fb For attitude feedback quaternions; q d q is the attitude command quaternion; e It is a quaternion for attitude difference.

[0101] (2) The output of the target compliance controller needs to be specially processed. Based on the rated torque of the motor and the joint reduction ratio, the output of the target compliance controller needs to be subject to saturation limit processing:

[0102]

[0103] Where, τ m Indicates the output torque of the joint; q represents the joint angle feedback velocity and the joint angle feedback position, respectively; J represents the Jacobian matrix; J T Let J represent the transpose of J; B is the damping parameter of the second-order system; K is the stiffness parameter of the second-order system. This represents the Cartesian feedback velocity of the robot obtained through the position sensor; x d x fb These represent the Cartesian planned position obtained through trajectory planning and the Cartesian feedback position of the robot obtained through the position sensor, respectively. Represents the Coriolis force; g(q) is the gravity term; τ fric τ represents the internal friction of the robot. max This indicates the maximum joint output torque.

[0104] Finally, the design of the virtual wall, as well as the servo control and floating control strategies, essentially involves setting constraint functions to adjust the magnitudes of stiffness and damping parameters. This patent describes the specific implementation methods for both constraint objectives, using a combination of two constraint functions.

[0105] Objective 1: To provide a simple virtual wall function

[0106] like Figure 4The diagram shown illustrates the robot's virtual wall function. The purpose of establishing the virtual wall is to protect the user's safety. As the robot approaches the virtual wall, the damping and stiffness parameters continuously increase to prevent further movement. Conversely, as the robot moves away from the virtual wall, the damping and stiffness parameters continuously decrease. The constraint parameters can be set as follows:

[0107]

[0108]

[0109] Where K represents the target stiffness value; K set K represents the preset stiffness parameter value of the second-order system. max B represents the maximum value of the preset stiffness parameter of the second-order system; B represents the target damping value; B set B represents the preset damping parameter value of the second-order system; max This represents the maximum value of the preset damping parameter of the second-order system; t represents time; C is a parameter value preset according to actual conditions; x fb Indicates the Cartesian feedback position; x wall Indicates the preset virtual wall value; x fb >x wall This indicates that the Cartesian feedback location is outside the three-dimensional space represented by the preset virtual wall values; x fb <x wall This indicates that the Cartesian feedback position is within the three-dimensional space represented by the preset virtual wall value.

[0110] Objective 2: To achieve both compliant control methods of following and floating.

[0111] Follow-up means that a robot can move under the action of an external force, and after the external force is removed, it can remain stable in its current position without moving. Liberation also allows a robot to move under the action of an external force, but after the external force is removed, it will return to its position before the external force was applied. These two types of compliant control can be easily implemented by setting stiffness parameters. The simplest constraint function is:

[0112]

[0113] Among them, K set This represents the preset stiffness parameter values ​​for the second-order system. Users can switch between floating and follow-up modes through the process interface, and the stiffness parameters will change accordingly.

[0114] like Figure 5 The diagram shown illustrates the principle of compliant control for a robot. Joint angle feedback position (q) and Cartesian feedback position (x) can be obtained from position sensors. fb ), and obtain the Cartesian program position (x) obtained from trajectory planning. dWhen the robot is subjected to external forces, a target compliant controller can be used to plan the position (x) according to the Cartesian algorithm. d ) and Cartesian feedback position (x fb The joint output torque (τ) is obtained by processing the joint angle feedback position (q) and other parameters. m ); utilizing the joint output torque (τ) m This allows for the control of the robot's movement. Furthermore, it can utilize Cartesian feedback to determine the position (x)... fb User operations (including user floating mode switching operations or follow-up mode switching operations) adjust the damping parameters and / or stiffness parameters of the second-order system in the target compliant controller to achieve virtual wall function, or floating control, or follow-up control.

[0115] Example 3

[0116] Figure 6 This is a structural schematic diagram of a robot compliant control device according to Embodiment 3 of the present invention. Figure 6 As shown, the device 600 includes:

[0117] The acquisition unit 610 is used to acquire the Cartesian planning position obtained from trajectory planning, and to acquire the joint angle feedback position and Cartesian feedback position using the position sensor;

[0118] The compliant control unit 620 is used to process the Cartesian planned position, Cartesian feedback position, and joint angle feedback position using the target compliant controller to obtain the joint output torque;

[0119] The compliant control unit 620 is also used to control the robot's movement using joint output torque;

[0120] The target compliant controller is obtained by performing dynamic modeling of the robot and dynamic characteristic modeling of the second-order system to obtain the original compliant controller, and then simplifying the original compliant controller; according to the preset virtual wall value, Cartesian feedback position, and preset parameters, the stiffness parameters and damping parameters of the second-order system in the target compliant controller are adjusted.

[0121] The preset parameters include one or more combinations of the following:

[0122] The maximum value of the preset stiffness parameter of the second-order system, the maximum value of the preset damping parameter of the second-order system, the preset stiffness parameter value of the second-order system, or the preset damping parameter value of the second-order system.

[0123] Among them, the preset stiffness parameter value of the second-order system is less than the preset maximum value of the stiffness parameter of the second-order system; the preset damping parameter value of the second-order system is less than the preset maximum value of the damping parameter of the second-order system.

[0124] The compliance control unit 620 is also used for:

[0125] In response to the user's servo mode switching operation, the stiffness parameter of the second-order system in the target compliant controller is adjusted to zero to achieve servo control of the robot.

[0126] The compliance control unit 620 is also used for:

[0127] In response to the user's floating mode switching operation, the stiffness parameters of the second-order system in the target compliant controller are adjusted to preset floating values ​​for floating control of the robot.

[0128] The robot compliant control device provided in this embodiment of the invention can execute any robot compliant control method provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0129] Specifically, the target compliance controller is obtained by simplifying the original compliance controller by removing the external torque term and the inverse of the Jacobian matrix.

[0130] Example 4

[0131] Figure 7 A schematic diagram of an electronic device 10 that can be used to implement embodiments of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0132] like Figure 7 As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the ROM 12 or loaded from storage unit 18 into the RAM 13. The RAM 13 may also store various programs and data required for the operation of the electronic device 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0133] Multiple components in electronic device 10 are connected to I / O interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of displays, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows electronic device 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0134] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as the compliant control methods of any of the robots described above.

[0135] In some embodiments, the compliant control method for any of the above-described robots can be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed on electronic device 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the compliant control method for any of the robots described above can be performed. Alternatively, in other embodiments, processor 11 can be configured to perform the compliant control method for any of the above-described robots by any other suitable means (e.g., by means of firmware).

[0136] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0137] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0138] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0139] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0140] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0141] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0142] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0143] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A compliant control method for a robot, characterized in that, include: Obtain the Cartesian planning position obtained from trajectory planning, and use the position sensor to obtain the joint angle feedback position and Cartesian feedback position; Using a target compliance controller, the Cartesian planned position, the Cartesian feedback position, and the joint angle feedback position are processed to obtain the joint output torque; The robot's movement is controlled by the torque output from the joints. The target compliant controller is obtained by performing dynamic modeling and second-order system dynamic characteristic modeling on the robot to obtain the original compliant controller, and then simplifying the original compliant controller; according to the preset virtual wall value, the Cartesian feedback position, and preset parameters, the stiffness parameters and damping parameters of the second-order system in the target compliant controller are adjusted; specifically, the target compliant controller is obtained by simplifying it by removing the external torque term and the inverse matrix of the Jacobian matrix from the original compliant controller; The method further includes: In response to the user's servo mode switching operation, the stiffness parameter of the second-order system in the target compliant controller is adjusted to zero to achieve servo control of the robot. The method further includes: In response to the user's floating mode switching operation, the stiffness parameters of the second-order system in the target compliant controller are adjusted to preset floating values ​​for floating control of the robot.

2. The method according to claim 1, characterized in that, The preset parameters include one or more combinations of the following: The maximum value of the preset stiffness parameter of the second-order system, the maximum value of the preset damping parameter of the second-order system, the preset stiffness parameter value of the second-order system, or the preset damping parameter value of the second-order system. Wherein, the preset stiffness parameter value of the second-order system is less than the maximum value of the preset stiffness parameter of the second-order system; the preset damping parameter value of the second-order system is less than the maximum value of the preset damping parameter of the second-order system.

3. A compliant control device for a robot, characterized in that, include: The acquisition unit is used to acquire the Cartesian planning position obtained from trajectory planning, and to acquire the joint angle feedback position and Cartesian feedback position using the position sensor; A compliance control unit is used to process the Cartesian planned position, the Cartesian feedback position, and the joint angle feedback position using a target compliance controller to obtain the joint output torque; The compliant control unit is also used to control the robot's movement by utilizing the joint output torque; The target compliant controller is obtained by performing dynamic modeling and second-order system dynamic characteristic modeling on the robot to obtain the original compliant controller, and then simplifying the original compliant controller. Based on preset virtual wall values, the Cartesian feedback position, and preset parameters, the stiffness and damping parameters of the second-order system in the target compliant controller are adjusted. Specifically, the target compliant controller is obtained by simplifying the original compliant controller by removing the external torque term and the inverse of the Jacobian matrix. The compliance control unit is also used for: In response to the user's servo mode switching operation, the stiffness parameter of the second-order system in the target compliant controller is adjusted to zero to achieve servo control of the robot. The compliance control unit is also used for: In response to the user's floating mode switching operation, the stiffness parameters of the second-order system in the target compliant controller are adjusted to preset floating values ​​for floating control of the robot.

4. An electronic device, characterized in that, The electronic device includes: At least one processor; and A memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the compliant control method of the robot according to any one of claims 1-2.

5. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed by a processor, implement the compliant control method of the robot according to any one of claims 1-2.

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