Compliant Control Method, Device, Electronic Equipment, and Storage Medium Based on a Robot Arm

Abstract

The present disclosure provides a compliance control method, apparatus, electronic device, and storage medium based on a robotic arm. The method includes: determining parameters of the single-joint movement of the robotic arm, where the parameters of the single-joint movement of the robotic arm include the inertia coefficient during the single-joint movement of the robotic arm and the time response parameter during the single-joint movement of the robotic arm; determining at least two dynamic models including the dynamic model of the single-joint of the robotic arm and the dynamic model of the robotic arm to which the single-joint of the robotic arm belongs based on the parameters of the single-joint movement of the robotic arm, and each of the dynamic models corresponds to different movement stages of the robotic arm; and controlling the robotic arm based on the dynamic models.

Description

Technical Field

[0001] The present disclosure relates to the field of automation control technologies, and particularly to a compliant control method, apparatus, electronic device, and storage medium based on a robotic arm. Background Art

[0002] A robotic arm can effectively replace manual labor in performing repetitive, heavy, high-intensity, and high-risk operations. At the same time, an automated operation system is controlled by a computer and has higher and more consistent quality control (product quality control). Therefore, it has great application potential and value in intelligent manufacturing industries such as 3C electronics and automobiles. Among them, 3C electronic products are the abbreviations of three types of electronic products: computer, communication, and consumer electronics.

[0003] In traditional automated operation scenarios, sensors such as vision and encoders are usually used to guide the robotic arm to perform point-to-point rigid motion operations. However, with the diversification and complexity of operation scenarios, a more efficient, accurate, and low-cost control solution needs to be sought. Summary of the Invention

[0004] The present disclosure provides a compliant control method, apparatus, electronic device, and storage medium based on a robotic arm to at least solve the above technical problems existing in the prior art.

[0005] According to a first aspect of the present disclosure, there is provided a compliant control method based on a robotic arm, the method including: determining parameters of a single-joint motion of the robotic arm, where the parameters of the single-joint motion of the robotic arm include an inertia coefficient during the single-joint motion of the robotic arm and a time response parameter during the single-joint motion of the robotic arm; based on the parameters of the single-joint motion of the robotic arm, determining at least two dynamic models including a dynamic model of the single-joint of the robotic arm and a dynamic model of the robotic arm to which the single-joint of the robotic arm belongs, each of the dynamic models corresponding to a different motion stage of the robotic arm; and controlling the robotic arm based on the dynamic models.

[0006] In an implementable manner, the determining the parameters of the single-joint motion of the robotic arm includes: obtaining a plurality of control signals of the robotic arm; controlling the robotic arm to perform a single-joint motion based on the plurality of control signals to obtain a plurality of response signals in response to the plurality of control signals; and determining the parameters of the single-joint motion of the robotic arm based on the plurality of control signals and the plurality of response signals.

[0007] In an implementable embodiment, determining the single-joint motion parameters of the robotic arm based on the plurality of control signals and the plurality of response signals includes: simulating the motion characteristics of the single joint of the robotic arm using a low-order system; respectively using the plurality of control signals and the plurality of response signals as the input parameters and output parameters of the low-order system to determine the single-joint motion parameters of the robotic arm.

[0008] In an implementable embodiment, determining at least two dynamic models including the dynamic model of the single joint of the robotic arm and the dynamic model of the robotic arm to which the single joint of the robotic arm belongs based on the parameters of the single-joint motion of the robotic arm, where each of the dynamic models corresponds to different motion stages of the robotic arm, includes: determining the transfer function of the single-joint motion system of the robotic arm based on the parameters of the single-joint motion of the robotic arm to obtain the dynamic model of the single joint of the robotic arm; determining the product of the transfer functions of the single-joint motion systems of the plurality of participating robotic arms as the transfer function of the robotic arm motion system to obtain the dynamic model of the robotic arm.

[0009] In an implementable embodiment, the method further includes: determining that the motion stage from the initial pose of the robotic arm to the desired pose of the robotic arm is the first motion stage, where there is a spacing distance between the desired pose and the working pose of the robotic arm; determining that the motion stage from the desired pose to the working pose is the second motion stage; determining that the transition stage between the first stage and the second stage is the third motion stage.

[0010] In an implementable embodiment, controlling the robotic arm based on the dynamic model includes: when the motion process of the robotic arm belongs to the first motion stage, controlling the robotic arm based on a motion control system; when the motion process of the robotic arm belongs to the second motion stage, controlling the robotic arm based on the dynamic model of the single joint of the robotic arm; when the motion process of the robotic arm belongs to the third motion stage, controlling the robotic arm based on the dynamic model of the robotic arm.

[0011] In an implementable embodiment, when the motion process of the robotic arm belongs to the second motion stage, controlling the robotic arm based on the dynamic model of the single joint of the robotic arm includes: planning the motion path of the robotic arm based on the dynamic model of the single joint of the robotic arm to obtain the working pose in the second motion stage; using the working pose to perform pose control and contact force control on the robotic arm.

[0012] In an implementable embodiment, when the movement of the robotic arm belongs to the third movement stage, controlling the robotic arm based on the dynamic model of the robotic arm includes: determining the pose of the third stage based on the dynamic model of the robotic arm, and using the pose of the third stage to perform pose control and contact force control on the robotic arm.

[0013] According to a second aspect of the present disclosure, there is provided a compliant control device based on a robotic arm. The device includes: a parameter determination module configured to determine parameters of the single-joint movement of the robotic arm, where the parameters of the single-joint movement of the robotic arm include the inertia coefficient during the single-joint movement of the robotic arm and the time response parameter during the single-joint movement of the robotic arm; a model determination module configured to determine at least two dynamic models including the dynamic model of the single-joint of the robotic arm and the dynamic model of the robotic arm to which the single-joint of the robotic arm belongs, each of the dynamic models corresponding to different movement stages of the robotic arm; and a control module configured to control the robotic arm based on the dynamic model.

[0014] In an implementable embodiment, the parameter determination module includes: a control signal acquisition sub-module configured to acquire a plurality of control signals of the robotic arm; a response signal acquisition sub-module configured to control the robotic arm to perform single-joint movement based on the plurality of control signals and obtain a plurality of response signals in response to the plurality of control signals; and a single-joint movement parameter determination sub-module configured to determine the parameters of the single-joint movement of the robotic arm based on the plurality of control signals and the plurality of response signals.

[0015] In an implementable embodiment, the single-joint movement parameter determination sub-module is specifically configured to simulate the movement characteristics of the single-joint of the robotic arm using a low-order system; and respectively use the plurality of control signals and the plurality of response signals as the input parameter and the output parameter of the low-order system to determine the parameters of the single-joint movement of the robotic arm.

[0016] In an implementable embodiment, the model determination module is specifically configured to determine the transfer function of the single-joint movement system of the robotic arm based on the parameters of the single-joint movement of the robotic arm to obtain the dynamic model of the single-joint of the robotic arm; and determine the product of the transfer functions of a plurality of single-joint movement systems of the robotic arm participating in the movement as the transfer function of the robotic arm movement system to obtain the dynamic model of the robotic arm.

[0017] In one implementable manner, the compliant control device based on the robotic arm further includes: a motion stage determination module, configured to determine that the motion stage from the initial pose of the robotic arm to the desired pose of the robotic arm is the first motion stage, where there is a separation distance between the desired pose and the operation pose of the robotic arm; determine that the motion stage from the desired pose to the operation pose is the second motion stage; and determine that the transition stage between the first stage and the second stage is the third motion stage.

[0018] In one implementable manner, the control module is specifically configured to control the robotic arm based on the motion control system when the motion process of the robotic arm belongs to the first motion stage; control the robotic arm based on the dynamic model of the single joint of the robotic arm when the motion process of the robotic arm belongs to the second motion stage; and control the robotic arm based on the dynamic model of the robotic arm when the motion process of the robotic arm belongs to the third motion stage.

[0019] In one implementable manner, the control module is specifically configured to plan the motion path of the robotic arm based on the dynamic model of the single joint of the robotic arm to obtain the operation pose in the second motion stage; and perform pose control and contact force control on the robotic arm using the operation pose.

[0020] In one implementable manner, the control module is specifically configured to determine the pose in the third stage based on the dynamic model of the robotic arm, and perform pose control and contact force control on the robotic arm using the pose in the third stage.

[0021] According to a third aspect of the present disclosure, there is provided an electronic device, including:

[0022] At least one processor; and

[0023] A memory communicatively connected to the at least one processor; wherein,

[0024] The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the method described in the present disclosure.

[0025] According to a fourth aspect of the present disclosure, there is provided a non-transitory computer-readable storage medium storing computer instructions, where the computer instructions are used to cause a computer to execute the method described in the present disclosure.

[0026] The compliant control method, device, electronic device and storage medium based on a robotic arm of the present disclosure simplify the complexity of dynamic modeling. At the same time, without the need for expensive contact force sensors, compliant control of the robotic arm can be achieved based on the simplified model, which not only overcomes the defect of the large difficulty in establishing a dynamic model in the related art, but also saves the hardware cost of the solution implementation, and has a wide range of applications and flexible applications.

[0027] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present disclosure, nor is it used to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] By referring to the accompanying drawings and reading the following detailed description, the above and other objects, features and advantages of the exemplary embodiments of the present disclosure will become easily understood. In the drawings, several embodiments of the present disclosure are shown in an exemplary and non-limiting manner, wherein:

[0029] In the drawings, the same or corresponding reference numerals represent the same or corresponding parts.

[0030] Figure 1 FIG. shows a schematic processing flow diagram of a compliant control method based on a robotic arm according to an embodiment of the present disclosure;

[0031] Figure 2 FIG. shows a schematic processing flow diagram of determining parameters of a single joint movement of a robotic arm in a compliant control method based on a robotic arm according to an embodiment of the present disclosure;

[0032] Figure 3 FIG. shows a schematic processing flow diagram of determining the single joint movement parameters of a robotic arm in a compliant control method based on a robotic arm according to an embodiment of the present disclosure;

[0033] Figure 4 FIG. shows a schematic processing flow diagram of determining a corresponding dynamic model in a compliant control method based on a robotic arm according to an embodiment of the present disclosure;

[0034] Figure 5 FIG. shows a model schematic in a compliant control method based on a robotic arm according to an embodiment of the present disclosure Figure 1 ;

[0035] Figure 6 FIG. shows a model schematic in a compliant control method based on a robotic arm according to an embodiment of the present disclosure Figure 2 ;

[0036] Figure 7 FIG. shows a schematic processing flow diagram of controlling a robotic arm based on a dynamic model in a compliant control method based on a robotic arm according to an embodiment of the present disclosure;

[0037] Figure 8 It shows a schematic diagram of the control principle of the compliant control method based on the robotic arm according to an embodiment of the present disclosure;

[0038] Figure 9 It shows a schematic diagram of the composition structure of the compliant control device based on the robotic arm according to an embodiment of the present disclosure;

[0039] Figure 10 It shows a schematic diagram of the composition structure of an electronic device according to an embodiment of the present disclosure. Detailed implementation manners

[0040] To make the objectives, features, and advantages of the present disclosure more obvious and understandable, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present disclosure.

[0041] In the related art, since the rigid motion control based on pose can no longer meet the increasingly diversified and complex robotic arm operation scenarios, technicians introduce contact force as a new control dimension to improve the applicability of the robotic arm control method in operation scenarios. Therefore, the compliant control based on force control has become one of the core technologies of robotic arm motion control.

[0042] Traditional compliant control schemes are mainly divided into passive compliant control and active compliant control. Passive compliant control needs to be realized by means of mechanisms, and there is a contradictory relationship between high stiffness and high flexibility for robotic arms based on passive compliant control. At the same time, the devices required for passive compliance control have high requirements, poor adaptability, a small application range, and many limitations; The robotic arm based on active compliant control has the ability to sense and control contact force, and can be divided into force / position hybrid control strategies, impedance control strategies, admittance control strategies, etc. according to the control strategy.

[0043] The force / position control hybrid control strategy simultaneously controls the force and position of each joint in the robotic arm, but the computational complexity of this strategy is relatively high; the impedance control strategy and the admittance control strategy are the mainstream of the robotic arm active compliance control methods in related technologies, and the robotic arm is controlled by controlling the dynamic relationship between the pose and the contact force of the robotic arm. Among them, the impedance control strategy performs contact force control based on the measured pose. Although the pose can be measured relatively accurately through the encoder and the robotic arm dynamics model, the impedance control strategy relies on the robotic arm dynamics model. Whether using Newton-Euler mechanics or Lagrangian mechanics to establish the robotic arm dynamics model, the modeling difficulty is extremely high, and the established dynamics model is also of high complexity, causing many inconveniences in practical applications. The admittance control strategy performs pose control based on the measured contact force. Although it does not depend on the robotic arm dynamics model, it has a high dependence on the measurement accuracy of the contact force, and it is difficult to accurately measure the contact force, and the force sensors required for measurement are also expensive.

[0044] Therefore, the embodiments of the present disclosure propose a compliance control method based on a robotic arm, which simplifies the process of establishing the dynamics model, reduces the complexity of modeling, and at the same time uses the established dynamics model to replace the force sensor, saving the hardware cost of the scheme implementation.

[0045] Figure 1 FIG. shows a schematic processing flow of the compliance control method based on the robotic arm according to the embodiments of the present disclosure.

[0046] Refer to Figure 1 , a processing flow of the compliance control method based on the robotic arm according to the embodiments of the present disclosure includes at least the following steps:

[0047] Step S101, determine the parameters of the single-joint movement of the robotic arm.

[0048] Among them, the parameters of the single-joint movement of the robotic arm may include: the inertia coefficient during the single-joint movement of the robotic arm and the time response parameter during the single-joint movement of the robotic arm.

[0049] In some embodiments, the time response parameter may include: rise time, delay time, peak time, settling time, overshoot and other parameters.

[0050] In some embodiments, the single-joint movement of the robotic arm can be understood as that only one axis moves during a complete movement process of the robotic arm.

[0051] In some embodiments, a specific implementation process for determining the parameters of the single-joint movement of the robotic arm is as Figure 2 shown, and at least includes the following steps:

[0052] Step S101a, obtain multiple control signals of the robotic arm.

[0053] In some embodiments, the control signals for the robotic arm can be diverse. For example, current, voltage, and pose can all be used as control signals. Different control signals can be obtained according to different operating scenarios of the robotic arm. Here, pose represents position and orientation, and any rigid body in a spatial coordinate system can be accurately and uniquely represented by its position and orientation to indicate its position state.

[0054] Step S101b: Based on multiple control signals, control the robotic arm to perform single-joint motion to obtain multiple response signals in response to the multiple control signals.

[0055] In some embodiments, the robotic arm receives multiple control signals, performs single-joint motion under the action of the multiple control signals, and outputs multiple response signals in response to the multiple control signals. As an example, the robotic arm receives a pose signal, performs single-joint motion under the action of the pose signal, and outputs a pose in response to the pose signal.

[0056] Step S101c: Based on the multiple control signals and the multiple response signals, determine the single-joint motion parameters of the robotic arm.

[0057] In some embodiments, a specific implementation process for determining the single-joint motion parameters of the robotic arm based on the multiple control signals and the multiple response signals is as follows Figure 3 as shown, and at least includes the following steps:

[0058] Step S101b1: Use a low-order system to simulate the motion characteristics of the single joint of the robotic arm.

[0059] In some embodiments, according to classical control theory, the relationship between input parameters and output parameters during the single-joint motion of the robotic arm is described by parameters such as transfer functions and ordinary differential equations. In the embodiments of the present disclosure, a low-order system is mainly used to simulate the motion characteristics of the single joint of the robotic arm. Here, a low-order system refers to a first-order or second-order system, that is, a control system with a first-order differential equation or a second-order differential equation as the motion equation.

[0060] Step S101b2: Respectively use the multiple control signals and the multiple response signals as the input parameters and output parameters of the low-order system to determine the single-joint motion parameters of the robotic arm.

[0061] In some embodiments, the multiple control signals for controlling the single-joint motion of the robotic arm and the multiple response signals in response to the multiple control signals are respectively used as the input and output parameters of the low-order system, and the parameters in the process of the low-order system simulating the single-joint motion of the robotic arm are continuously adjusted. When the input and output parameters of the low-order system match the multiple control signals and the multiple response signals during the single-joint motion of the robotic arm, the continuously adjusted obtained parameters are determined as the single-joint motion parameters of the robotic arm.

[0062] Step S102: Based on the parameters of the movement of a single joint of the robotic arm, determine at least two dynamic models including the dynamic model of the single joint of the robotic arm and the dynamic model of the robotic arm to which the single joint of the robotic arm belongs.

[0063] Among them, each dynamic model corresponds to a different movement stage of the robotic arm.

[0064] In some embodiments, a specific implementation process of determining at least two dynamic models including the dynamic model of the single joint of the robotic arm and the dynamic model of the robotic arm to which the single joint of the robotic arm belongs based on the parameters of the movement of the single joint of the robotic arm is as follows Figure 4 shown, and at least includes the following steps:

[0065] Step S102a: Based on the parameters of the movement of the single joint of the robotic arm, determine the transfer function of the movement system of the single joint of the robotic arm, and obtain the dynamic model of the single joint of the robotic arm.

[0066] Step S102b: Determine the product of the transfer functions of multiple movement systems of the single joints of the robotic arm participating in the movement as the transfer function of the movement system of the robotic arm, and obtain the dynamic model of the robotic arm.

[0067] An exemplary description of steps S102a - S102b is as follows:

[0068] 1) Simulate the movement characteristics of the single joint of the robotic arm with a first - order system. The mathematical model T of the transfer function in the movement system of the single joint of the robotic arm s can be shown as the following formula:

[0069]

[0070] Among them, s0 is the system sensitivity; τ s is the system time function.

[0071] According to the foregoing method, continuously adjust the first - order system to determine the parameters of the movement of the single joint of the robotic arm, thereby obtaining the system sensitivity and the system time function, and further determining the transfer function of the movement system of the single joint of the robotic arm, and obtaining the first - order dynamic model of the single joint of the robotic arm.

[0072] In the process of multi - joint movement of the robotic arm, according to the classical control theory, the robotic arm can be regarded as composed of multiple single joints of the robotic arm participating in the movement in series.

[0073] Therefore, the first - order dynamic models of each single joint (axis) of the robotic arm can be established in sequence, and the product of the transfer functions of multiple movement systems of the single joints of the robotic arm participating in the movement is determined as the transfer function of the movement system of the robotic arm, and the dynamic model of the robotic arm is obtained.

[0074] Among them, the transfer function of the robotic arm motion system is shown as follows:

[0075]

[0076] Among them, s0 is the system sensitivity, and τ s is the system time function, and T s1 to T sn are respectively the first-order dynamics models of the single joints of the robotic arm participating in the motion, and T s is the dynamics model of the robotic arm during multi-joint motion.

[0077] 2) As Figure 5 shown, the motion characteristics of the single joint of the robotic arm are simulated by a second-order system, and the mathematical model T s of the transfer function in the single joint motion system of the robotic arm can be shown as follows:

[0078]

[0079] Among them, ω n is the undamped natural frequency of the system, ξ is the system damping coefficient, and s is the pole.

[0080] According to the foregoing method, the second-order system is continuously adjusted to determine the parameters of the single joint motion of the robotic arm, and thus parameters such as the system damping coefficient are obtained, and further the transfer function of the single joint motion system of the robotic arm is determined, and the second-order dynamics model of the single joint of the robotic arm is obtained.

[0081] Correspondingly, as Figure 6 shown, the dynamics model of the robotic arm can be obtained, and the transfer function of the robotic arm motion system is shown as follows:

[0082]

[0083] Among them, ω n is the undamped natural frequency of the system, ξ is the system damping coefficient, s is the pole, and T s1 to T sn are respectively the second-order dynamics models of the single joints of the robotic arm participating in the motion, and T s is the dynamics model of the robotic arm during multi-joint motion.

[0084] Figure 5 In Figure 6 , r(t) shown represents the input parameter of the model, which can be any control instruction; y(t) represents the output parameter of the model, which can be a response signal in response to any control instruction.

[0085] In some embodiments, the parameters of the single-joint movement of the robotic arm depend on the dynamic model used. For example, if a second-order system is used to simulate the movement characteristics of the single-joint of the robotic arm, the parameters of the single-joint movement of the robotic arm may further include the system damping coefficient ξ in addition to the aforementioned inertia coefficient and time response parameters.

[0086] In some embodiments, the lower the system order, the rougher the model and the lower the accuracy. For example, the accuracy of the model obtained by simulating the movement characteristics of the single-joint of the robotic arm with a second-order system is higher than that of the model obtained by simulating the movement characteristics of the single-joint of the robotic arm with a first-order system.

[0087] Step S103, controlling the robotic arm based on the dynamic model.

[0088] In some embodiments, the movement process of the robotic arm can be divided into different movement stages. Based on the application scenario of compliant control, the movement process of the robotic arm is divided into the following three different movement stages in the embodiments of the present disclosure:

[0089] Determine that the movement stage from the initial pose of the robotic arm to the desired pose is the first movement stage.

[0090] In some embodiments, in the first movement stage, the robotic arm performs multi-axis composite movement and quickly moves from the initial pose to the desired pose. Therefore, the first movement stage can also be called the rapid movement stage of large-range multi-axis composite. Among them, there is a distance between the desired pose and the operation pose of the robotic arm, and the desired pose can be understood as any pose near the operation pose.

[0091] Determine that the movement stage from the desired pose to the operation pose is the second movement stage.

[0092] In some embodiments, the second movement stage is the main stage of the compliant operation of the robotic arm. The robotic arm performs single-axis movement with a small adjustment amplitude. Therefore, the second movement stage can also be called the small-range single-axis fine-tuning movement stage.

[0093] Determine that the transition stage between the first stage and the second stage is the third movement stage.

[0094] In some embodiments, the third stage is the transition stage between the first stage and the second stage, and is the transition stage from rigid pose control to compliant force control.

[0095] In some embodiments, a specific implementation process of controlling the robotic arm based on the dynamic model, such as Figure 7 shown, at least includes the following steps:

[0096] Step S103a, when the movement process of the robotic arm belongs to the first movement stage, controlling the robotic arm based on the motion control system.

[0097] In some embodiments, the requirements for motion in the first motion stage are mainly speed and accurate pose. Since there is no contact with the environment, there is no requirement for contact force. Therefore, a rigid motion control algorithm is adopted for motion control in this stage, and it can be achieved through pose control.

[0098] Step S103b, when the motion process of the robotic arm belongs to the second motion stage, control the robotic arm based on the dynamic model of a single joint of the robotic arm.

[0099] In some embodiments, by planning the motion path of the robotic arm based on the dynamic model of a single joint of the robotic arm, the requirements for the operation pose can be achieved through single-axis motion, that is, the operation pose in the second motion stage is obtained; meanwhile, pose control and contact force control are performed on the robotic arm using the operation pose.

[0100] Step S103c, when the motion process of the robotic arm belongs to the third motion stage, control the robotic arm based on the dynamic model of the robotic arm.

[0101] In some embodiments, in the third motion stage, it is necessary to control the contact force, and at the same time, it is impossible to achieve pose control by kinematic planning of the single-joint motion of the robotic arm. Therefore, compliant control needs to be performed according to the dynamic model of the robotic arm.

[0102] In some embodiments, the pose in the third motion stage is determined based on the dynamic model of the robotic arm, and pose control and contact force control are performed on the robotic arm using the pose in the third motion stage.

[0103] Among them, although the accuracy of the dynamic model of the robotic arm is lower than that of the dynamic model of a single joint of the robotic arm, the transition stage has a short duration and low control requirements, and the dynamic model of the robotic arm can meet the usage requirements.

[0104] For the second motion stage (small-range single-axis fine-tuning motion stage) and the third motion stage (transition stage), the principle of the compliant control scheme adopted is as Figure 8 shown. A contact force control loop is added outside the pose control loop. The inner loop of the robotic arm control system is a pose closed-loop control based on pose measurement feedback such as an encoder, and the outer loop of the robotic arm control system is a contact force closed-loop control based on the dynamic model established in the embodiments of the present disclosure.

[0105] Among them, x ref represents the reference value required in the control process; x0 represents the intermediate variable in the control process; x m represents the value fed back by the robotic arm in the control process, which is the measured value (actual value).

[0106] In some embodiments, the inner loop and the outer loop of the robotic arm control system are nested and affect each other. The outer loop control affects the inner loop control, and the result of the inner loop control is also fed back to the outer loop, thereby affecting the effect of the outer loop control.

[0107] Compared with the impedance control method in the related art, the compliance control method proposed in the embodiments of the present disclosure does not require the establishment of a complex dynamic model, simplifies the complexity of dynamic modeling, and can achieve compliance control based on the simplified model; compared with the admittance control method in the related art, it does not require expensive contact force sensors, and can achieve compliance control of the contact force through pose control; it has a wide range of applications and is flexible in application. A force control loop can be added outside the pose control loop of the robotic arm using the rigid motion control method to achieve compliance control of the robotic arm.

[0108] Figure 9 The composition structure diagram of a compliance control device based on a robotic arm in an embodiment is shown.

[0109] Reference Figure 9 , a compliance control device based on a robotic arm in an embodiment, the compliance control device 90 based on a robotic arm includes: a parameter determination module 901, configured to determine the parameters of the single-joint motion of the robotic arm, and the parameters of the single-joint motion of the robotic arm include the inertia coefficient during the single-joint motion of the robotic arm and the time response parameter during the single-joint motion of the robotic arm; a model determination module 902, configured to determine at least two dynamic models including the dynamic model of the single-joint of the robotic arm and the dynamic model of the robotic arm to which the single-joint of the robotic arm belongs based on the parameters of the single-joint motion of the robotic arm, and each dynamic model corresponds to a different motion stage of the robotic arm; a control module 903, configured to control the robotic arm based on the dynamic model.

[0110] In some embodiments, the parameter determination module 901 includes: a control signal acquisition sub-module 9011, configured to acquire a plurality of control signals of the robotic arm; a response signal acquisition sub-module 9012, configured to control the robotic arm to perform single-joint motion based on the plurality of control signals to obtain a plurality of response signals in response to the plurality of control signals; a single-joint motion parameter determination sub-module 9013, configured to determine the single-joint motion parameters of the robotic arm based on the plurality of control signals and the plurality of response signals.

[0111] In some embodiments, the single-joint motion parameter determination sub-module 9013 is specifically configured to simulate the motion characteristics of the single-joint of the robotic arm using a low-order system; respectively use the plurality of control signals and the plurality of response signals as the input parameters and output parameters of the low-order system to determine the single-joint motion parameters of the robotic arm.

[0112] In some embodiments, the model determination module 902 is specifically configured to determine the transfer function of the robotic arm single-joint motion system based on the parameters of the robotic arm single-joint motion, so as to obtain the dynamic model of the robotic arm single-joint; determine the product of the transfer functions of multiple robotic arm single-joint motion systems participating in the motion as the transfer function of the robotic arm motion system, so as to obtain the dynamic model of the robotic arm.

[0113] In some embodiments, the compliance control device 90 of the robotic arm further includes: a motion stage determination module 904, configured to determine that the motion stage from the initial pose of the robotic arm to the desired pose of the robotic arm is the first motion stage, and there is an interval distance between the desired pose and the operation pose of the robotic arm; determine that the motion stage from the desired pose to the operation pose is the second motion stage; determine that the transition stage between the first stage and the second stage is the third motion stage.

[0114] In some embodiments, the control module 903 is specifically configured to control the robotic arm based on the motion control system when the motion process of the robotic arm belongs to the first motion stage; control the robotic arm based on the dynamic model of the robotic arm single-joint when the motion process of the robotic arm belongs to the second motion stage; control the robotic arm based on the dynamic model of the robotic arm when the motion process of the robotic arm belongs to the third motion stage.

[0115] In some embodiments, the control module 903 is specifically configured to plan the motion path of the robotic arm based on the dynamic model of the robotic arm single-joint to obtain the operation pose in the second motion stage; perform pose control and contact force control on the robotic arm using the operation pose.

[0116] In some embodiments, the control module 903 is specifically configured to determine the pose in the third stage based on the dynamic model of the robotic arm, and perform pose control and contact force control on the robotic arm using the pose in the third stage.

[0117] According to an embodiment of the present disclosure, the present disclosure also provides an electronic device and a readable storage medium.

[0118] Figure 10 The schematic block diagram of an exemplary electronic device 1000 that can be used to implement the embodiments of the present disclosure 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 processing, cellular phones, smart phones, wearable electronic devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are only examples and are not intended to limit the implementation of the present disclosure described and / or claimed herein.

[0119] As Figure 10 shown, the electronic device 1000 includes a computing unit 1001, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) 1002 or a computer program loaded from a storage unit 1008 into a random access memory (RAM) 1003. In the RAM 1003, various programs and data required for the operation of the electronic device 1000 can also be stored. The computing unit 1001, the ROM 1002, and the RAM 1003 are connected to each other via a bus 1004. An input / output (I / O) interface 1005 is also connected to the bus 1004.

[0120] Multiple components in the electronic device 1000 are connected to the I / O interface 1005, including: an input unit 1006, such as a keyboard, a mouse, etc.; an output unit 1007, such as various types of displays, speakers, etc.; a storage unit 1008, such as a magnetic disk, an optical disc, etc.; and a communication unit 1009, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 1009 allows the electronic device 1000 to exchange information / data with other electronic devices via a computer network such as the Internet and / or various telecommunication networks.

[0121] The computing unit 1001 can be various general and / or special processing components with processing and computing capabilities. Some examples of the computing unit 1001 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The computing unit 1001 executes the various methods and processes described above, such as the compliant control method based on a robotic arm. For example, in some embodiments, the compliant control method based on a robotic arm can be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as the storage unit 1008. In some embodiments, part or all of the computer program can be loaded and / or installed onto the electronic device 1000 via the ROM 1002 and / or the communication unit 1009. When the computer program is loaded into the RAM 1003 and executed by the computing unit 1001, one or more steps of the compliant control method based on a robotic arm described above can be executed. Alternatively, in other embodiments, the computing unit 1001 can be configured to execute the compliant control method based on a robotic arm in any other appropriate manner (e.g., by means of firmware).

[0122] The various embodiments of the systems and techniques described above in this document can be implemented in digital electronic circuitry, integrated circuit systems, field programmable gate arrays (FPGA), application specific integrated circuits (ASIC), application specific standard products (ASSP), systems on a chip (SOC), complex programmable logic devices (CPLD), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special-purpose or general-purpose programmable processor that receives data and instructions from a storage system, at least one input device, and at least one output device, and transmits the data and instructions to the storage system, the at least one input device, and the at least one output device.

[0123] The program code for implementing the methods of the present disclosure can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when the program codes are executed by the processor or controller, the functions / operations specified in the flowchart and / or block diagram are implemented. The program code can be executed entirely on the machine, partially on the machine, executed partially on the machine as an independent software package and partially on a remote machine, or executed entirely on a remote machine or server.

[0124] In the context of the present disclosure, a machine-readable medium can be a tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of a machine-readable storage medium would include electrical connections based on one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0125] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer 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 a pointing device (e.g., a mouse or a trackball) through which the user can provide input to the computer. Other kinds of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and the input received from the user can be in any form (including acoustic input, voice input, or tactile input).

[0126] The systems and techniques described herein can be implemented in a computing system including backend components (e.g., as a data server), or a computing system including middleware components (e.g., an application server), or a computing system including frontend components (e.g., a user computer having a graphical user interface or a web browser through which the user can interact with an implementation of the systems and techniques described herein), or a computing system including any combination of such backend components, middleware components, or frontend components. The components of the system can be interconnected to each other by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: local area network (LAN), wide area network (WAN), and the Internet.

[0127] A computer system can include a client and a server. The client and the server are generally far from each other and usually interact through a communication network. 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, or a server of a distributed system, or a server incorporating a blockchain.

[0128] It should be understood that various forms of the processes shown above can be used, with steps reordered, added, or deleted. For example, the steps recited in this disclosure can be executed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution disclosed in this disclosure can be achieved, and no limitation is imposed herein.

[0129] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In the description of this disclosure, "a plurality" means two or more unless otherwise specifically defined.

[0130] As described above, this is only a specific embodiment of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present disclosure can easily think of changes or substitutions, which should all be covered within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims described above.

Claims

1. A compliant control method based on a robotic arm, characterized in that, The method includes: Determining parameters of the single-joint movement of the robotic arm, where the parameters of the single-joint movement of the robotic arm include the inertia coefficient during the single-joint movement of the robotic arm and the time response parameter during the single-joint movement of the robotic arm; Based on the parameters of the single-joint movement of the robotic arm, determining at least two dynamic models including the dynamic model of the single-joint of the robotic arm and the dynamic model of the robotic arm to which the single-joint of the robotic arm belongs, and each of the dynamic models corresponds to a different movement stage of the robotic arm; Controlling the robotic arm based on the dynamic model; The method further includes: determining that the movement stage from the initial pose of the robotic arm to the desired pose of the robotic arm is the first movement stage, where there is a spacing distance between the desired pose and the working pose of the robotic arm; determining that the movement stage from the desired pose to the working pose is the second movement stage; determining that the transition stage between the first movement stage and the second movement stage is the third movement stage; The controlling the robotic arm based on the dynamic model includes: when the movement process of the robotic arm belongs to the first movement stage, controlling the robotic arm based on the motion control system; when the movement process of the robotic arm belongs to the second movement stage, controlling the robotic arm based on the dynamic model of the single-joint of the robotic arm; when the movement process of the robotic arm belongs to the third movement stage, controlling the robotic arm based on the dynamic model of the robotic arm.

2. The method according to claim 1, wherein The determining the parameters of the single-joint movement of the robotic arm includes: Obtaining a plurality of control signals of the robotic arm; Controlling the robotic arm to perform single-joint movement based on the plurality of control signals to obtain a plurality of response signals in response to the plurality of control signals; Based on the plurality of control signals and the plurality of response signals, determining the parameters of the single-joint movement of the robotic arm.

3. The method according to claim 2, characterized in that, The determining the parameters of the single-joint movement of the robotic arm based on the plurality of control signals and the plurality of response signals includes: Simulating the movement characteristics of the single-joint of the robotic arm using a low-order system; Respectively using the plurality of control signals and the plurality of response signals as the input parameter and the output parameter of the low-order system to determine the parameters of the single-joint movement of the robotic arm.

4. The method according to claim 1, characterized in that, The determining at least two dynamic models including the dynamic model of the single-joint of the robotic arm and the dynamic model of the robotic arm to which the single-joint of the robotic arm belongs based on the parameters of the single-joint movement of the robotic arm, and each of the dynamic models corresponds to a different movement stage of the robotic arm, includes: Determining the transfer function of the single-joint movement system of the robotic arm based on the parameters of the single-joint movement of the robotic arm to obtain the dynamic model of the single-joint of the robotic arm; Determining the product of the transfer functions of a plurality of participating single-joint movement systems of the robotic arm as the transfer function of the robotic arm movement system to obtain the dynamic model of the robotic arm.

5. The method according to claim 1, characterized in that, The controlling the robotic arm based on the dynamic model of the single-joint of the robotic arm when the movement process of the robotic arm belongs to the second movement stage includes: Plan the motion path of the robotic arm based on the dynamic model of a single joint of the robotic arm to obtain the working pose in the second motion stage; Use the working pose to perform pose control and contact force control on the robotic arm.

6. The method according to claim 1, characterized in that, When the motion of the robotic arm belongs to the third motion stage, controlling the robotic arm based on the dynamic model of the robotic arm includes: Determine the pose in the third motion stage based on the dynamic model of the robotic arm, and use the pose in the third motion stage to perform pose control and contact force control on the robotic arm.

7. A compliant control device based on a robotic arm, characterized in that, The device includes: A parameter determination module for determining parameters of the motion of a single joint of the robotic arm, where the parameters of the motion of a single joint of the robotic arm include the inertia coefficient during the motion of a single joint of the robotic arm and the time response parameter during the motion of a single joint of the robotic arm; A model determination module for determining at least two dynamic models including the dynamic model of a single joint of the robotic arm and the dynamic model of the robotic arm to which the single joint of the robotic arm belongs based on the parameters of the motion of a single joint of the robotic arm, and each of the dynamic models corresponds to a different motion stage of the robotic arm; A control module for controlling the robotic arm based on the dynamic model; The device further includes a motion stage determination module for determining that the motion stage from the initial pose of the robotic arm to the desired pose of the robotic arm is the first motion stage, and there is a spacing distance between the desired pose and the working pose of the robotic arm; determining that the motion stage from the desired pose to the working pose is the second motion stage; determining that the transition stage between the first motion stage and the second motion stage is the third motion stage; The control module is further configured to control the robotic arm based on a motion control system when the motion of the robotic arm belongs to the first motion stage; control the robotic arm based on the dynamic model of a single joint of the robotic arm when the motion of the robotic arm belongs to the second motion stage; control the robotic arm based on the dynamic model of the robotic arm when the motion of the robotic arm belongs to the third motion stage.

8. An electronic device, characterized in that, Includes: At least one processor; And A memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the compliant control method for a robotic arm according to any one of claims 1-6.

9. A non-transitory computer-readable storage medium storing computer instructions, characterized in that, The computer instructions are used to cause the computer to execute the compliant control method for a robotic arm according to any one of claims 1-6.

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