Constant force control method and device of robot and electronic equipment

Abstract

The embodiment of the invention provides a constant force control method and device of a robot and electronic equipment, and relates to the technical field of robots. The method comprises the steps that in the process that a robot works on a target object, external force borne by the tail end of the robot when the tail end of the robot is in the current first pose is obtained, and according to preset target constant force, the target position adjusting direction and the external force, the target position adjusting amount is obtained through calculation; obtaining a target angle adjustment amount in a preset posture adjustment control direction corresponding to the external force moment applied to the tail end of the robot at the first posture, wherein the target angle adjustment amount is used for enabling a tool at the tail end of the adjusted robot to be attached to the surface of the target object; adjusting the first pose according to the target position adjustment amount and the target adjustment angle to obtain a second pose at the next moment; and controlling the robot to move according to the second pose. Therefore, constant force control of the robot can be achieved, and the contact area between the robot tail end tool and the surface of the target object is increased.

Description

Technical Field

[0001] The present application relates to the field of robotics technology, and in particular to a method, device and electronic equipment for controlling a constant force of a robot. Background Art

[0002] As an important part of artificial intelligence, robots have been widely infiltrated into various fields and have become an important force in promoting scientific and technological progress. Especially in industrial production, collaborative robots have gradually replaced traditional industrial robots with their high safety and low power consumption, becoming the preferred solution in many scenarios. Collaborative robots can not only effectively avoid safety hazards in human-machine collaboration, but also provide higher flexibility and efficiency in some tasks, meeting the needs of modern production for intelligence and efficiency.

[0003] Usually, workers need robots to complete repetitive and intensive work. Common application scenarios for collaborative robots include welding workpieces, workpiece grinding, human massage, and shaft hole assembly. Depending on the type of work, tools need to be installed at the end of the robot flange. Moreover, during the operation, it is usually necessary to maintain a constant force between the end tool and the target object.

[0004] The commonly used constant force control method currently generally achieves constant force contact by position adjustment. However, due to various reasons, the end tool may not fit well with the surface of the target object, resulting in poor working results. For example, in the application scenario of robot grinding, it is necessary to ensure that the end of the robot fits well with the workpiece. If the fit is not good, the grinding effect will be affected (for example, it is not polished cleanly). Summary of the invention

[0005] The embodiments of the present application provide a constant force control method, device, electronic device and readable storage medium for a robot, which can increase the contact area between the robot's end tool and the surface of the target object by adjusting the robot's end posture under the premise of achieving constant force control of the robot, so as to avoid poor working results due to small contact area.

[0006] The embodiments of the present application can be implemented as follows:

[0007] In a first aspect, an embodiment of the present application provides a constant force control method of a robot, the method comprising:

[0008] During the robot operation on the target object, the external force on the robot end when the robot end is in the current first posture is obtained, and the target position adjustment amount is calculated according to the preset target constant force, the target position adjustment direction and the external force, wherein the first position in the first posture is the position currently moved to based on the preset operation trajectory;

[0009] Obtaining a target angle adjustment amount in a preset posture adjustment control direction corresponding to the external force torque applied to the robot end in the first posture, wherein the target angle adjustment amount is used to make the tool of the robot end after adjustment fit with the surface of the target object, and a target angle adjustment amount in a posture adjustment control direction is used to indicate a rotation angle adjustment amount in a rotation direction;

[0010] Adjusting the first posture according to the target position adjustment amount and the target angle adjustment amount to obtain a second posture at a next moment;

[0011] The robot is controlled to move according to the second posture.

[0012] In a second aspect, an embodiment of the present application provides a constant force control device for a robot, the device comprising:

[0013] A first calculation module is used to obtain the external force on the end of the robot when the end of the robot is in the current first posture during the robot's operation on the target object, and calculate the target position adjustment amount according to the preset target constant force, the target position adjustment direction and the external force, wherein the first position in the first posture is the position currently moved to based on the preset operation trajectory;

[0014] A second calculation module is used to obtain a target angle adjustment amount in a preset posture adjustment control direction corresponding to the external force torque applied to the robot end in the first posture, wherein the target angle adjustment amount is used to make the tool of the robot end after adjustment fit with the surface of the target object, and a target angle adjustment amount in a posture adjustment control direction is used to indicate a rotation angle adjustment amount in a rotation direction;

[0015] A processing module, used for adjusting the first posture according to the target position adjustment amount and the target angle adjustment amount to obtain a second posture at a next moment;

[0016] A control module is used to control the movement of the robot according to the second posture.

[0017] In a third aspect, an embodiment of the present application provides an electronic device, comprising a processor and a memory, wherein the memory stores machine executable instructions that can be executed by the processor, and the processor can execute the machine executable instructions to implement the constant force control method of the robot described in the aforementioned embodiment.

[0018] In a fourth aspect, an embodiment of the present application provides a readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the constant force control method of the robot as described in the aforementioned embodiment is implemented.

[0019] The constant force control method, device, electronic device and readable storage medium of the robot provided by the embodiment of the present application, in the process of the robot operating on the target object, the external force received by the robot end when the robot end is in the current first posture is obtained, and the target position adjustment amount is calculated according to the preset target constant force, the target position adjustment direction and the external force, and the target angle adjustment amount in the preset posture adjustment control direction corresponding to the external force torque received by the robot end when it is in the first posture is obtained, the first position in the above-mentioned first posture is the position currently moved to based on the preset operation trajectory, the target angle adjustment amount is used to make the tool of the robot end after adjustment fit with the surface of the target object, and the target angle adjustment amount of a posture adjustment control direction is used to indicate the rotation angle adjustment amount in a rotation direction; then, according to the target position adjustment amount and the target angle adjustment amount, the first posture is adjusted to obtain the second posture at the next moment, and then the robot movement is controlled according to the second posture. In this way, under the premise of realizing the constant force control of the robot, by adjusting the posture of the robot end, the contact area between the tool at the robot end and the surface of the target object can be increased to avoid the situation where the operation effect is poor due to the small contact area. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 A block diagram of an electronic device provided in an embodiment of the present application;

[0022] Figure 2 One of the flow charts of the constant force control method of the robot provided in the embodiment of the present application;

[0023] Figure 3 A second flow chart of the constant force control method of a robot provided in an embodiment of the present application;

[0024] Figure 4 A schematic diagram of a constant force control application scenario provided in an embodiment of the present application;

[0025] Figure 5 A schematic diagram of robot posture adjustment based on a six-dimensional sensor provided in an embodiment of the present application;

[0026] Figure 6 for Figure 2 One of the flowchart diagrams of the sub-steps included in step S120;

[0027] Figure 7 for Figure 2 2 is a flow chart of the sub-steps included in step S120;

[0028] Figure 8 A schematic diagram of the distribution of ultrasonic sensors provided in an embodiment of the present application at the end of a robot;

[0029] Fig. 9 The third flowchart of the constant force control method of the robot provided in the embodiment of the present application;

[0030] Fig.10 A fourth flow chart of the constant force control method of a robot provided in an embodiment of the present application;

[0031] Fig.11 A fifth flow chart of the constant force control method of a robot provided in an embodiment of the present application;

[0032] Fig.12 One of the block diagrams of the constant force control device of the robot provided in the embodiment of the present application;

[0033] Fig.13 The second block diagram of the constant force control device of the robot provided in the embodiment of the present application;

[0034] Fig.14 The third block diagram of the constant force control device of the robot provided in the embodiment of the present application.

[0035] Icon: 100 - electronic device; 110 - memory; 120 - processor; 130 - communication unit; 200 - constant force control device of robot; 201 - planning module; 210 - first calculation module; 220 - second calculation module; 230 - processing module; 240 - control module; 250 - analysis module. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0037] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0038] It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0039] Constant force control requires the help of force sensors. Currently, before performing constant force control operations, the six-axis force sensor is generally calibrated to zero. After that, the constant desired force and control parameters are set according to the operation conditions. When the end of the robot contacts an object in the environment, the object will generate an interaction force on the end of the robot, causing the force detected by the six-axis force sensor to deviate from the desired force (that is, the constant desired force set previously). At this time, the position will be adjusted according to the difference between the actual force and the desired force to achieve constant force control operations.

[0040] In some application scenarios of constant force control, due to the influence of various factors, the end tool under the above-mentioned constant force control method may not fit well with the surface of the object, which may lead to poor robot operation. For example, when using a robot to massage the human body, because the surface of the human body is uneven and has a certain degree of flexibility, when using the existing constant force control method for massage, the end tool of the robot often fails to fit completely with the human skin, which greatly affects the user experience and limits the promotion and use of constant force control systems. For example, in the application scenario of robot grinding, it is also necessary to ensure that the end of the robot fits the workpiece. If the fit is not good, the grinding effect will be affected, such as not being polished clean.

[0041] In response to the above situation, the embodiments of the present application provide a constant force control method, device, electronic device and readable storage medium for a robot, which can increase the contact area between the robot's end tool and the surface of the target object by adjusting the robot's end posture while achieving constant force control of the robot, so as to avoid poor operating results due to small contact area.

[0042] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0043] Please refer to Figure 1 , Figure 1 A block diagram of an electronic device 100 provided in an embodiment of the present application. The electronic device 100 may be, but is not limited to, a robot, a control device of a robot (such as a computer, etc.), etc. The electronic device 100 may include a memory 110, a processor 120, and a communication unit 130. The memory 110, the processor 120, and the communication unit 130 are electrically connected to each other directly or indirectly to achieve data transmission or interaction. For example, these components can be electrically connected to each other via one or more communication buses or signal lines.

[0044] The memory 110 is used to store programs or data. The memory 110 may be, but is not limited to, a random access memory (RAM), a read only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), etc.

[0045] The processor 120 is used to read / write data or programs stored in the memory 110 and perform corresponding functions. For example, the memory 110 stores a constant force control device 200 of a robot, and the constant force control device 200 of the robot includes at least one software function module that can be stored in the memory 110 in the form of software or firmware. The processor 120 executes various functional applications and data processing by running software programs and modules stored in the memory 110, such as the constant force control device 200 of the robot in the embodiment of the present application, that is, realizing the constant force control method of the robot in the embodiment of the present application.

[0046] The communication unit 130 is used to establish a communication connection between the electronic device 100 and other communication terminals through a network, and to send and receive data through the network.

[0047] It should be understood that Figure 1 The structure shown is only a schematic diagram of the structure of the electronic device 100. The electronic device 100 may also include Figure 1 More or fewer components as shown, or with Figure 1 Different configurations shown. Figure 1 Each component shown in the figure can be implemented by hardware, software or a combination thereof.

[0048] Please refer to Figure 2 , Figure 2 One of the flow diagrams of the constant force control method of the robot provided in the embodiment of the present application. The method is applied to the above-mentioned electronic device. The specific process of the constant force control method of the robot is described in detail below. In this embodiment, the method may include steps S110 to S140.

[0049] Step S110, during the robot's operation on the target object, the external force applied to the robot end when the robot end is in the current first posture is obtained, and the target position adjustment amount is calculated based on the preset target constant force, the target position adjustment direction and the external force.

[0050] Step S120, obtaining a target angle adjustment amount in a preset posture adjustment control direction corresponding to the external force torque applied to the robot terminal when the robot terminal is in the first posture.

[0051] In this embodiment, during the robot's operation on the target object, when the robot reaches a position according to a preset operation trajectory, the target position adjustment amount in the preset target position adjustment direction and the target angle adjustment amount in the preset posture adjustment control direction corresponding to the current posture of the robot can be analyzed. The current posture is the first posture mentioned above, and the first position in the first posture is the current position moved to based on the preset operation trajectory. Among them, the target position adjustment amount and the target angle adjustment amount can be obtained in sequence, or they can be obtained at the same time, and the specific execution order can be determined in combination with actual needs. The above-mentioned robot can be an industrial robot or a collaborative robot; when it is a collaborative robot, it can be a six-degree-of-freedom collaborative robot or a collaborative robot with other degrees of freedom.

[0052] The preset target constant force includes the size and direction of the desired constant force. The preset target position adjustment direction is used to indicate the adjustment direction when the position adjustment is expected to achieve constant force. It can be set in advance in combination with actual needs, for example, it can be pre-designated as the Z axis of the robot end. A force sensor can be set at the end of the robot, and then the force detected by the force sensor is used as the external force received by the robot end in the current posture. Thereafter, the target position adjustment amount in the target adjustment direction is calculated based on the external force, the target constant force, and the target adjustment direction. The target position adjustment amount may be a positive number, a negative number, or 0, which is specifically determined by the actual situation. It can be understood that, in general, when the robot end is located at a position after the first position is adjusted based on the target position adjustment amount, the force detected by the force sensor indicates that the external force received by the robot end at this time is the target constant force or close to the target constant force.

[0053] The preset attitude adjustment control direction is used to indicate the rotation direction. The specific number and specific direction can be set in advance according to actual needs. For example, the attitude adjustment control direction is pre-specified as the rotation direction around the X-axis of the robot end and the rotation direction around the Y-axis of the robot end. The robot end will also be subjected to the external force torque corresponding to the external force in the current posture. The target angle adjustment amount in each attitude adjustment control direction corresponding to the external force torque can be calculated in any way. The target angle adjustment amount may be a positive number, a negative number, or 0, which is determined by the actual situation. It can be understood that, in general, when the posture of the robot end is in the posture after the first posture in the first posture is adjusted based on the angle adjustment amount, the tool of the robot end is more in line with the surface of the target object; that is, the target angle adjustment amount is used to make the tool of the robot end after adjustment fit with the surface of the target object, and the target angle adjustment amount of a posture adjustment control direction is used to indicate the rotation angle adjustment amount in a rotation direction.

[0054] Step S130, adjusting the first posture according to the target position adjustment amount and the target angle adjustment amount to obtain a second posture at the next moment.

[0055] Step S140: controlling the movement of the robot according to the second posture.

[0056] When the target position adjustment amount of the target position adjustment direction and the target angle adjustment amount of each posture adjustment control direction are obtained, the first posture can be adjusted based on the target position adjustment amount of the target position adjustment direction and the target angle adjustment amount of each posture adjustment control direction, and the adjusted first posture can be used as the second posture at the next moment, and then the robot movement can be controlled according to the second posture so that the robot end is in the second posture at the next moment.

[0057] In this way, by adjusting the end position of the robot, constant force can be achieved, and the contact area between the robot end tool and the surface of the target object can be increased to avoid poor working results due to small contact area.

[0058] Optionally, the preset operation trajectory can be obtained by teaching or by other means, which can be determined in combination with actual needs. When the operation trajectory is obtained by teaching, the trajectory recording can be completed by dragging teaching or jogging to obtain the operation trajectory.

[0059] However, the teaching method can only be applied to working scenarios where the working object is stationary relative to the robot. If the working object needs to change frequently or is in a complex environment, then teaching is required before each operation. It is not easy to achieve by dragging teaching or inching and other methods to record points, such as cumbersome. For example, if the robot is required to massage a person, when massaging different users, it is necessary to teach before massaging the current user each time, otherwise the operation cannot be performed. For constant force control, robots are often used for repetitive operations, and the scenes are roughly fixed. The relative posture between different working objects and the robot may change slightly. In this case, it can be achieved through Figure 3 In step S101, the operation trajectory is obtained.

[0060] Please refer to Figure 3 , Figure 3 The second flow chart of the constant force control method of the robot provided in the embodiment of the present application. In this embodiment, before step S110, the method may further include step S101.

[0061] Step S101, before operating the target object, an image of the target object is obtained by a visual sensor, and the operating trajectory is obtained based on the obtained image analysis.

[0062] In this embodiment, before operating on the target object, an image of the target object is obtained through a visual sensor, and then the operating trajectory corresponding to the target object is analyzed and determined in combination with the operating requirements and the obtained image. The operating trajectory is the trajectory along which the robot moves during the operation on the target object.

[0063] For example, Figure 4 As shown in FIG. 1 , a six-dimensional force sensor and a massage head are installed at the end of the collaborative robot, and the use of the six-dimensional force sensor and the massage head for human body massage or other operations is the most common application of collaborative robots. A camera can be provided to obtain an image of the user as the target object. Figure 4 In the scene shown, the positions of the robot, camera, and bed remain unchanged, and the user's body shape and height are the only variables. With the traditional drag-to-teach method, each user needs to be taught at each point when performing massage. If the operating area is large, the drag-to-teach operation is large and the overall process is cumbersome.

[0064] In this embodiment, a visual sensor is used instead of dragging teaching. Before the customer performs the massage, the visual sensor takes a picture of the human body and automatically obtains the points that need massage by analyzing the obtained three-dimensional image. Then, according to the relative position relationship between the camera and the robot in the world coordinate system, the massage points are converted to the robot coordinate system, and the massage operation can be directly performed.

[0065] Among them, in the method of using visual sensors for massage operations, the relative position of the visual sensor and the robot, the relative position of the visual sensor and the bed, etc. are configured when the environment is first set up, so that each time the point is determined based on the image, the point can be converted to the robot coordinate system. In this way, only the user needs to be changed to achieve repeated massage operations, which can improve work efficiency. The above scenarios can be expanded to other similar scenarios, such as polishing workpieces, force control assembly, etc.

[0066] After obtaining the preset operation trajectory, the robot can be controlled to move according to the operation trajectory to operate on the target object of this time. Optionally, in order to increase flexibility, an option of whether to turn on constant force control can be set. When constant force control is not turned on, the robot can be controlled to only execute the operation trajectory without constant force effect. When constant force control is turned on, the position can be adjusted to produce a constant force effect during the operation of the robot based on the operation trajectory according to the set target constant force, constant force control parameters, etc. Among them, the target constant force may include the magnitude and direction of the force, etc.; the constant force control parameters may include the parameters used when calculating the position adjustment amount. For example, when using the PID algorithm to calculate the position adjustment amount, the constant force control parameters may include the third parameter of PID, and the constant force control parameters may also include the adjustment speed, etc.

[0067] As a possible implementation, Figure 5 In this method, the robot end is provided with a six-dimensional force sensor, and the actual data currently obtained by the six-dimensional force sensor can be low-pass filtered to obtain the external force F currently received by the robot end. s And external force moment M s ,Right now Figure 5 F s represents the actual force information obtained based on the six-dimensional force sensor, M s Represents the actual torque information obtained based on the six-dimensional force sensor.

[0068] When external force F is obtained s In the case of d , Target position adjustment direction and external force F s The force tracker can be used to calculate the target position adjustment amount in the target position adjustment direction based on the above information (i.e. Figure 5 The position correction x in 1 ).in, Figure 5 S1 in the figure is used to indicate the position adjustment direction of the constant force control, that is, to indicate the target position adjustment direction; d Indicates the preset operation track.

[0069] Optionally, the target position adjustment amount can be obtained by a PID control algorithm. That is, the Z direction of the robot end is the target position adjustment direction; the external force F s With the target constant force F d The force difference ΔF is obtained by differential calculation, and then the incremental PID method (i.e. Figure 5 The force tracking controller in the robot is output as shown in formula (1), and the distance adjustment of the robot's current end position in the Z direction of the robot end (i.e., the target position adjustment) is output. The position is adjusted according to the target position adjustment to reduce the force difference and achieve constant force control. Wherein, formula (1) is:

[0070] Δu=k p (e i -e i-1 )+k i e i +k d (e t -2e i-1 +e i-2 ) (1)

[0071] Among them, k p Indicates the proportional coefficient in PID parameters, k i Indicates the integral coefficient in the PID parameters, k d Indicates the differential coefficient in PID parameters; e i Represents the error at the current moment, e i-1 represents the error at the previous moment, e i-2 Represents the error between the first two moments.

[0072] It is understandable that the target position adjustment direction may also be set to other directions, which may be determined based on actual needs.

[0073] Optionally, to increase flexibility, an option of whether to turn on posture adjustment can be set. When constant force control and posture adjustment are not turned on, only the position of the robot can be corrected; when posture adjustment is turned on, the posture can be adjusted to increase the contact area between the tool and the target object.

[0074] As a possible implementation method, the robot end is provided with a six-dimensional force sensor, which can be Figure 6 The method shown is based on the six-axis force sensor to obtain the target angle adjustment amount. In this method, if the target position adjustment amount is also obtained based on the six-axis force sensor, then Figure 5 The process shown adjusts the current posture. Figure 6 , Figure 6 for Figure 2One of the flowchart diagrams of the sub-steps included in step S120. In this embodiment, step S120 may include sub-steps S121 to S122.

[0075] Sub-step S121, obtaining the external force torque obtained by the six-dimensional force sensor.

[0076] Sub-step S122, calculating a first angle adjustment amount as the target angle adjustment amount according to the admittance control equation, each posture adjustment control direction and the external force torque.

[0077] You can get the preset control direction of each posture adjustment. Figure 5 S2 in the constant force control is used to indicate the position adjustment direction, that is, to indicate the target position adjustment direction. For example, That is, the control direction of the posture adjustment is the rotation direction around the X-axis of the robot end and the rotation direction around the Y-axis of the robot end.

[0078] The target angle adjustment amount calculated in each attitude adjustment control direction is the attitude adjustment amount (also called attitude correction amount). The transformation relationship between torque and attitude angle can be established by the admittance control method. The relationship is shown in formula (2). The first angle adjustment amount is calculated as the attitude adjustment amount, that is, Figure 5 The attitude compliance controller in the example obtains the target angle adjustment value (i.e. Figure 5 The attitude correction x in 2 ). Wherein, formula (2) is as follows:

[0079]

[0080] Where M represents the inertia matrix; B represents the damping matrix; K represents the stiffness matrix; F e (t) represents the external force and torque sensed by the sensor at the current moment; x e (t) represents the position increment of the robot end at the current moment; x e (t-1) represents the position increment of the robot end at the previous moment; Indicates the speed of the robot end at the last moment; Indicates the current speed of the robot end; It represents the acceleration generated by the external force and torque at the current moment; ΔT represents the time interval.

[0081] Taking the scenario of using a robot to massage the human body as an example, since the surface of the human body is uneven and the friction is large, the torque changes when performing constant force massage. Then, using the admittance control algorithm, in the example shown in S2 above, the corresponding posture adjustment angle θ when the torque changes under the unknown surface can be obtained. x and θy , that is, the target angle adjustment amount in the rotation direction around the X-axis of the robot end is θ x The target angle adjustment amount in the rotation direction around the X-axis at the Y end of the machine is θ y . Substituting the external force and torque into the above formula (2), we get x e (t) includes the increments of position and attitude angle, that is, the position increment generated by admittance control based on the external force and torque detected by the force sensor is [xyzrxryrz]. The increment of the attitude angle corresponding to the rotation direction around the X-axis of the robot end can be taken as θ x , the increment corresponding to the rotation direction around the X axis of the Y end of the machine is taken as θ y , that is, taking rx as θ x , let ry be θ y .

[0082] When the target position adjustment amount in the target position adjustment direction and the target angle adjustment amount in the posture adjustment control direction are obtained, the transformation information can be determined, and the current first posture can be adjusted based on the transformation information to obtain the second posture at the next moment, and the robot movement can be controlled according to the second posture.

[0083] For example, as in the above example, we can obtain θ x ,θ y After Δu, the homogeneous transformation matrix T can be constructed. Δ , where θ x ,θ y ,θ z =0 indicates T Δ The rotation matrix in T Δ The translation in the Z direction in the translation matrix, T Δ The translation in the X and Y directions of the translation matrix in is 0. Δ The homogeneous transformation matrix T corresponding to the current posture of the robot end t Multiplying them together, we can get the homogeneous transformation matrix T of the robot end at the next moment. t+1 :T t+1 =T t T Δ . Homogeneous transformation matrix T t The first position of the robot end is included in T. t+1 By performing the inverse solution, we can obtain the position (i.e. angle) of each joint of the robot at the next moment, and the robot moves according to this position.

[0084] As another possible implementation, the robot end is provided with a plurality of distance sensors, and the distance sensors are used to obtain the distance to the surface of the target object. When the robot end is in a horizontal state, the distances measured by the plurality of distance sensors are the same. Figure 7 The method shown is based on the distance sensor to obtain the target angle adjustment. Figure 7 , Figure 7 for Figure 2 FIG. 2 is a flow chart of sub-steps included in step S120. In this embodiment, step S120 may include sub-steps S124 to S125.

[0085] Sub-step S124, obtaining the distances measured by each of the plurality of distance sensors.

[0086] Sub-step S125, adjusting the control direction according to the obtained multiple angles and each posture, and calculating a second angle adjustment amount as the target angle adjustment amount.

[0087] In this embodiment, for each determined posture adjustment control direction, the distance corresponding to the posture adjustment control direction can be determined from the distances currently measured by multiple distance sensors, and then based on the distance corresponding to the posture adjustment control direction, the second angle adjustment amount corresponding to the posture adjustment control direction can be calculated, and the second angle adjustment amount can be used as the target angle adjustment amount. Afterwards, the first posture can be adjusted according to the target angle adjustment amount and the target position adjustment amount to obtain the second posture, and the robot can be motion controlled according to the second posture.

[0088] The following combines the above How to obtain the target angle adjustment amount θ of the rotation direction around the X-axis of the robot end x , and the target angle adjustment amount in the rotation direction around the Y-axis of the robot end are used as an example.

[0089] The distance sensor may be an ultrasonic sensor. Figure 8 As shown, four ultrasonic sensors are installed at the end of the robot, usually located at the four corners of the end, which is equivalent to dividing the XY plane of the end into four quadrants. One ultrasonic sensor is set in each quadrant. Figure 4 The upper right part of the end shown by the large circle in the middle) is provided with an ultrasonic sensor ②, and the second quadrant (i.e. Figure 4 An ultrasonic sensor ① is arranged in the upper left part of the end indicated by the large circle in the middle. Figure 4 The lower left part of the end indicated by the large circle in the middle) is provided with an ultrasonic sensor ③, and the fourth quadrant (i.e. Figure 4Ultrasonic sensor ④ is set in the lower right part of the end shown by the large circle in the middle. The distance between ultrasonic sensors ① and ③ and the distance between ultrasonic sensors ② and ④ are both L, and the distance between ultrasonic sensors ① and ② and the distance between ultrasonic sensors ③ and ④ are both W. Assume that the measurement distances of ultrasonic sensors ①, ②, ③, and ④ are: d 1 d 2 d 3 d 4 The distance difference provided by the up and down sensors (the up sensors are ① and ②, and the down sensors are ③ and ④) is used to calculate the pitch angle θ pitch The distance difference provided by the left and right sensors (the left sensors are ① and ③, and the right sensors are ② and ④) is used to calculate the roll angle θ roll . Pitch angle θ pitch , roll angle θ roll This is the second angle adjustment amount mentioned above.

[0090] If all ultrasonic sensors are installed at the same height and horizontally (without tilt), ideally, if the end of the robot is placed horizontally, the distances measured by the four ultrasonic sensors should be equal, that is: d 1 =d 2 =d 3 =d 4 If the end of the robot is tilted, the measurement distances of different ultrasonic sensors will be different.

[0091] The pitch angle θ can be calculated according to the following formula: pitch : The roll angle θ is calculated according to the following formula: roll :

[0092] The pitch angle θ can be calculated based on the distance difference of the ultrasonic sensor pitch and roll angle θ roll Determine the attitude error matrix T off The attitude error matrix T off As shown in the following formulas (3) and (4):

[0093] R off =R z (0)R y (θ pitch )R x (θ roll ) (3)

[0094]

[0095] Among them, 0 1 =

[000] T , 0 2 =

[000] ,

[0096]

[0097] When β = 0,

[0098] According to the homogeneous transformation matrix T corresponding to the first pose of the current end of the robot t And the pose error matrix T o ' ff Calculate the homogeneous transformation matrix T of the robot end at the next moment t+1 :T t+1 =T t T o ' ff Among them, the pose error matrix T o ' ff The attitude error matrix T off And the position error matrix, which includes the calculated target position adjustment amount, for example, the Δu corresponding to the Z direction in the above example indicates the translation in the Z direction in the position error matrix, and the translation in the X and Y directions in the position error matrix is ​​0. After that, the inverse kinematics can be used to solve the joint angle of the robot at the next moment. In this way, by changing the joint angle, the distance between the end of the robot and the surface of the human body can be made consistent.

[0099] As a possible implementation method, the robot movement can be controlled in the following manner: first, the end of the robot is moved to a preset position according to a preset operation trajectory, and then the posture is adjusted, and the end of the robot is moved to the adjusted posture; then, the robot is moved to a preset posture specified by the operation trajectory again, and the posture is adjusted again, and the end of the robot is moved to the adjusted posture, and the above operations are repeated until the operation is completed. For example, the preset working trajectory includes preset positions 0-3, then at time 1, the robot end is moved to the preset position 1, and the target position adjustment amount and the target angle adjustment amount are calculated according to the force condition of the robot end at the preset position 1, and then the posture at time 1 is adjusted according to the target position adjustment amount and the target angle adjustment amount, and the posture of the robot end at time 2 is the posture after the posture adjustment at time 1; at time 3, the robot end is moved to the preset position 2, and the target position adjustment amount and the target angle adjustment amount are calculated according to the force condition of the robot end at the preset position 2, and then the posture of the robot end at time 2 is adjusted according to the target position adjustment amount and the target angle adjustment amount, and the posture of the robot end at time 3 is the posture after the posture adjustment at time 3; and so on.

[0100] The current constant force control method generally does not perform abnormal detection, which can easily lead to danger. For example, when the six-dimensional force sensor fails, it cannot be detected in time, resulting in failure to handle it in time (for example, stopping the system operation in time), which can easily lead to danger.

[0101] In this embodiment, multiple types of sensors can be used to verify each other, so that safety can be guaranteed while the robot performs constant force control and ensures that the end of the robot is in contact with the object.

[0102] As a possible implementation, abnormality detection can be performed in the following manner. The robot end is provided with a six-dimensional force sensor and a plurality of distance sensors for obtaining the distance to the surface of the target object. When the robot end is in a horizontal state, the distances measured by the plurality of distance sensors are the same. Fig. 9 , Fig. 9 The third flow chart of the constant force control method of the robot provided in the embodiment of the present application. In this embodiment, the method may further include steps S151 to S153.

[0103] Step S151, obtaining a first angle adjustment amount calculated based on data of the six-dimensional force sensor.

[0104] Step S152: obtaining a second angle adjustment amount calculated based on the distances measured by the multiple distance sensors.

[0105] Step S153: determining whether the constant force control process is abnormal according to the first angle adjustment amount and the second angle adjustment amount.

[0106] In this embodiment, at the current moment, the first angle adjustment amount in each posture adjustment control direction calculated based on the torque data of the six-dimensional force sensor can be obtained, and the second angle adjustment amount in each posture adjustment control direction calculated based on the distance measured by the distance sensor can be obtained. When the target angle adjustment amount is calculated based on the data of the six-dimensional force sensor, the first angle adjustment amount is the target angle adjustment amount; when the target angle adjustment amount is calculated based on the distances measured by the multiple distance sensors, the second angle adjustment amount is the target angle adjustment amount. The specific method for obtaining the first angle adjustment amount and the second angle adjustment amount can be referred to the above description, and will not be repeated here.

[0107] According to the specific judgment method set, whether the constant force control process is abnormal can be judged based on the first angle adjustment amount and the second angle adjustment amount, that is, whether the constant force control system is abnormal can be judged.

[0108] Optionally, for each posture adjustment control direction, it can be determined whether the positive and negative signs of the first angle adjustment amount and the second angle adjustment amount of the posture adjustment control direction are the same. If the positive and negative signs of the first angle adjustment amount and the second angle adjustment amount of each posture adjustment control direction are the same, it is determined that it is not possible to determine whether the constant force control system is abnormal based on the positive and negative signs of the angle adjustment amount, or it is directly determined that the constant force control system is normal. If the positive and negative signs of the first angle adjustment amount and the second angle adjustment amount of at least one posture adjustment control direction are different, it can be determined that the constant force control system is abnormal.

[0109] Optionally, for each posture adjustment control direction, it can be determined whether the angle difference between the first angle adjustment amount and the second angle adjustment amount of the posture adjustment control direction is greater than a preset angle difference. The preset angle difference can be set in combination with the measurement noise of the six-dimensional force sensor and the distance sensor. If the angle difference of each posture adjustment control direction is not greater than the preset angle difference, it is determined that it is not possible to determine whether the constant force control system is abnormal based on the angle difference, or it is directly determined that the constant force control system is normal. If the angle difference of at least one posture adjustment control direction is greater than the preset angle difference, it can be determined that the constant force control system is abnormal.

[0110] Optionally, the above two methods may be combined. If one of the methods determines that there is an abnormality, then it is determined that the constant force control system is abnormal.

[0111] The following example illustrates how to determine whether the constant force control system is abnormal based on the first angle adjustment amount and the second angle adjustment amount. In the following example, the first angle adjustment amount includes θ x ,θ y The second angle adjustment includes the pitch angle θ pitch and roll angle θ roll The angle difference can be calculated according to formula (5).

[0112]

[0113] The positive and negative values ​​of the first angle adjustment value and the second angle adjustment value are judged. roll )≠sign(θ x ) or sign(θ pitch )≠sign(θ y ), it is determined that the constant force control system is abnormal.

[0114] To judge the two angle differences, if θ 1 >ε 1 Or θ 2 >ε 2 , that is, there is an angle difference greater than the preset angle difference, then it is determined that the constant force control system is abnormal.

[0115] As another possible implementation, the robot end is further provided with a plurality of distance sensors for obtaining the distance to the surface of the target object. When the robot end is in a horizontal state, the distances measured by the plurality of distance sensors are the same. When the target angle adjustment amount is calculated based on the data of the six-dimensional force sensor, the distance adjustment amount can be obtained by Fig.10 Anomaly detection is performed in the manner shown. Fig.10 , Fig.10 The fourth flowchart of the constant force control method of the robot provided in the embodiment of the present application. In this embodiment, after step S140, the method may further include steps S161 to S162.

[0116] Step S161, determining whether the multiple distances obtained by the multiple distance sensors after controlling the movement of the robot according to the second posture are all greater than a preset distance.

[0117] Step S162: If the distance obtained by at least one distance sensor is not greater than the preset distance, it is determined that the six-dimensional force sensor is abnormal.

[0118] After controlling the movement of the robot according to the second posture, the distances measured by the multiple distance sensors at this time can be obtained, and then it is determined whether the multiple distances are all greater than the preset distance. The preset distance can be determined based on the safe distance between the robot end and the surface of the target object. If at least one of the measured distances is not greater than the preset distance, it can be determined that the constant force control system is abnormal, and it can also be determined that the six-dimensional force sensor is abnormal.

[0119] As another possible implementation, you can also use Fig.11 Anomaly detection is performed in the manner shown. Fig.11 , Fig.11 The fifth flowchart of the constant force control method of the robot provided in the embodiment of the present application. In this embodiment, the method may further include steps S171 to S172.

[0120] Step S171, based on the image data obtained multiple times by the visual sensor, determine whether the robot end surface gradually becomes parallel to the target object surface or remains parallel to the target object surface before and after adjustment based on the target angle adjustment amount.

[0121] Step S172: If not, it is determined that the constant force control process is abnormal.

[0122] Under normal circumstances, after adjustment based on the target angle adjustment amount, the angle between the surface of the robot end and the surface of the target object (not greater than 90 degrees) becomes smaller than before the adjustment, or remains parallel. A visual sensor can be used to obtain images before and after the real posture of the robot end is adjusted based on the target angle adjustment amount, that is, to obtain images before and after step S140, and then judge based on the image whether the surface of the robot end gradually becomes parallel to the surface of the target object or remains parallel to the surface of the target object before and after the adjustment of the target angle adjustment amount. If the surface of the robot end gradually becomes parallel to the surface of the target object or remains parallel to the surface of the target object before and after the adjustment of the target angle adjustment amount, it can be determined that the constant force control system is normal. If the surface of the robot end does not gradually become parallel to the surface of the target object or remain parallel to the surface of the target object before and after the adjustment of the target angle adjustment amount, it is determined that the constant force control system is abnormal.

[0123] In the event of an abnormality, the robot can be directly controlled to stop running, thus ensuring safety.

[0124] In this embodiment, the adjustment amount of the terminal posture can be calculated based on the data information of the six-dimensional force sensor and the change in force and torque to ensure that there is no torque change and constant force during operations such as grinding. Among them, when calculating the adjustment amount corresponding to the posture, the torque change is converted into a posture adjustment angle based on the torque information of the six-dimensional force sensor with the help of the admittance control algorithm, and constant force control of the surface of the target object is jointly achieved. Posture adjustment can also be performed based on the distance sensor. In this way, a posture adjustment relationship between the distance sensor and the end of the robot can be established, and the angle adjustment amount can be calculated based on the distance sensor, and then the posture of the robot end at the next moment is obtained to achieve fit with the surface of the target object. In addition, a data verification function for multiple types of sensors is also designed. During the operation of the constant force control system, the terminal posture adjustment angle is calculated in real time based on the six-dimensional force sensor and the distance sensor. If the adjustment angles calculated by the two methods are in opposite directions or the difference is large, the constant force control system is considered abnormal and stops running. At the same time, a visual sensor can be introduced to take pictures to obtain images of the robot terminal before and after adjustment based on the calculated target angle adjustment amount, and judge whether the control is abnormal based on the image. When the constant force control system is abnormal, pictures can also be taken to obtain the current position of the robot, determine the angle required for the terminal posture adjustment at this time, and analyze the angles generated by the above two methods. If the posture adjustment angle of one of the methods is close, the constant force system operation is restored. If the posture adjustment angles of the two methods have a large difference, it is considered a system failure, and the cause of the failure is generated, which is convenient for the operator to check.

[0125] In order to execute the corresponding steps in the above embodiments and various possible methods, a method for implementing a constant force control device 200 of a robot is provided below. Optionally, the constant force control device 200 of the robot can adopt the above Figure 1 The device structure of the electronic device 100 is shown. Fig.12 , Fig.12 One of the block diagrams of the constant force control device 200 of the robot provided in the embodiment of the present application. It should be noted that the basic principle and technical effect of the constant force control device 200 of the robot provided in this embodiment are the same as those of the above-mentioned embodiments. For the sake of brief description, for the parts not mentioned in this embodiment, reference can be made to the corresponding contents in the above-mentioned embodiments. In this embodiment, the constant force control device 200 of the robot may include: a first calculation module 210, a second calculation module 220, a processing module 230 and a control module 240.

[0126] The first calculation module 210 is used to obtain the external force on the robot end when the robot end is in the current first posture during the robot operation on the target object, and calculate the target position adjustment amount according to the preset target constant force, the target position adjustment direction and the external force. The first position in the first posture is the current position moved to based on the preset operation trajectory.

[0127] The second calculation module 220 is used to obtain a target angle adjustment amount in a preset posture adjustment control direction corresponding to the external force torque applied to the robot end in the first posture. The target angle adjustment amount is used to make the tool of the robot end after adjustment fit the surface of the target object, and a target angle adjustment amount in a posture adjustment control direction is used to indicate a rotation angle adjustment amount in a rotation direction.

[0128] The processing module 230 is used to adjust the first posture according to the target position adjustment amount and the target angle adjustment amount to obtain a second posture at a next moment.

[0129] The control module 240 is used to control the movement of the robot according to the second posture.

[0130] Please refer to Fig.13 , Fig.13 The second block diagram of the constant force control device 200 of the robot provided in the embodiment of the present application. In this embodiment, the constant force control device 200 of the robot may further include a planning module 201. The planning module 201 is used to obtain an image of the target object through a visual sensor before operating the target object, and obtain the operation trajectory based on the obtained image analysis.

[0131] Please refer to Fig.14 , Fig.14 The third block diagram of the constant force control device 200 of the robot provided in the embodiment of the present application. In this embodiment, the constant force control device 200 of the robot may also include an analysis module 250. The analysis module 250 is used to determine whether the constant force control system is abnormal. The specific manner in which the analysis module 250 determines whether the constant force control system is abnormal can refer to the description of the abnormality judgment process in the previous text, which will not be repeated here. The control module 240 is also used to control the robot to stop running when it is determined that an abnormality has occurred.

[0132] Optionally, the above modules can be stored in the form of software or firmware. Figure 1 The memory 110 shown in the figure may be fixed in the operating system (OS) of the electronic device 100 and may be Figure 1 Meanwhile, the data and program codes required for executing the above modules may be stored in the memory 110.

[0133] An embodiment of the present application also provides a readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the constant force control method of the robot is implemented.

[0134] In summary, the embodiment of the present application provides a constant force control method, device, electronic device and readable storage medium of a robot. During the operation of the robot on the target object, the external force received by the robot end when the robot end is in the current first posture is obtained, and the target position adjustment amount is calculated according to the preset target constant force, the target position adjustment direction and the external force, and the target angle adjustment amount in the preset posture adjustment control direction corresponding to the external force torque received by the robot end when the robot end is in the first posture is obtained. The first position in the above-mentioned first posture is the position currently moved to based on the preset operation trajectory. The target angle adjustment amount is used to make the tool of the adjusted robot end fit with the surface of the target object. The target angle adjustment amount of a posture adjustment control direction is used to indicate the rotation angle adjustment amount in a rotation direction; then, according to the target position adjustment amount and the target angle adjustment amount, the first posture is adjusted to obtain the second posture at the next moment, and then the robot movement is controlled according to the second posture. In this way, under the premise of realizing the constant force control of the robot, the contact area between the tool at the end of the robot and the surface of the target object can be increased by adjusting the posture of the end of the robot to avoid the situation where the operation effect is poor due to the small contact area.

[0135] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0136] In addition, the functional modules in the various embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.

[0137] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0138] The above description is only an optional embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A constant force control method for a robot, characterized in that: The method comprises: During the robot operation on the target object, the external force on the robot end when the robot end is in the current first posture is obtained, and the target position adjustment amount is calculated according to the preset target constant force, the target position adjustment direction and the external force, wherein the first position in the first posture is the position currently moved to based on the preset operation trajectory; Obtaining a target angle adjustment amount in a preset posture adjustment control direction corresponding to the external force torque applied to the robot end in the first posture, wherein the target angle adjustment amount is used to make the tool of the robot end after adjustment fit with the surface of the target object, and a target angle adjustment amount in a posture adjustment control direction is used to indicate a rotation angle adjustment amount in a rotation direction; Adjusting the first posture according to the target position adjustment amount and the target angle adjustment amount to obtain a second posture at a next moment; The robot is controlled to move according to the second posture.

2. The method according to claim 1, characterized in that The robot end is provided with a six-dimensional force sensor, and the obtaining of a target angle adjustment amount in a preset posture adjustment control direction corresponding to the external force torque received by the robot end in the first posture includes: Obtaining an external force torque obtained by the six-dimensional force sensor; According to the admittance control equation, each posture adjustment control direction and the external force torque, a first angle adjustment amount is calculated as the target angle adjustment amount.

3. The method according to claim 2, characterized in that The robot end is also provided with a plurality of distance sensors for obtaining the distance to the surface of the target object. When the robot end is in a horizontal state, the distances measured by the plurality of distance sensors are the same. The method further comprises: Determining whether a plurality of distances obtained by the plurality of distance sensors after controlling the movement of the robot according to the second posture are all greater than a preset distance; If the distance obtained by at least one distance sensor is not greater than the preset distance, it is determined that the six-dimensional force sensor is abnormal.

4. The method according to claim 1, characterized in that: The robot end is provided with a plurality of distance sensors for obtaining the distance to the surface of the target object. When the robot end is in a horizontal state, the distances measured by the plurality of distance sensors are the same. The obtaining of the target angle adjustment amount in the preset posture adjustment control direction corresponding to the external force torque applied to the robot end in the first posture includes: Obtaining distances measured by each of the plurality of distance sensors; According to the obtained multiple distances and each posture adjustment control direction, a second angle adjustment amount is calculated to be used as the target angle adjustment amount.

5. The method according to any one of claims 1 to 4, characterized in that: The robot end is provided with a six-dimensional force sensor and a plurality of distance sensors for obtaining the distance to the surface of the target object. When the robot end is in a horizontal state, the distances measured by the plurality of distance sensors are the same. The method further comprises: Obtaining a first angle adjustment amount calculated based on the data of the six-axis force sensor, wherein when the target angle adjustment amount is calculated based on the data of the six-axis force sensor, the first angle adjustment amount is the target angle adjustment amount; Obtaining a second angle adjustment amount calculated based on the distances measured by the multiple distance sensors, wherein when the target angle adjustment amount is calculated based on the distances measured by the multiple distance sensors, the second angle adjustment amount is the target angle adjustment amount; Whether the constant force control process is abnormal is determined according to the first angle adjustment amount and the second angle adjustment amount.

6. The method according to claim 5, characterized in that The determining whether the constant force control process is abnormal according to the first angle adjustment amount and the second angle adjustment amount includes: When the positive and negative signs of the first angle adjustment amount and the second angle adjustment amount corresponding to the same posture adjustment control direction are different, it is determined that the constant force control process is abnormal; and / or, When the angle difference between the first angle adjustment amount and the second angle adjustment amount corresponding to the same posture adjustment control direction is greater than the preset angle difference, it is determined that the constant force control process is abnormal.

7. The method according to any one of claims 1 to 4, characterized in that: The method further comprises: Based on image data obtained multiple times by the visual sensor, determining whether the surface of the robot end gradually becomes parallel to the surface of the target object or remains parallel to the surface of the target object before and after adjustment based on the target angle adjustment amount; If not, it is determined that the constant force control process is abnormal.

8. The method according to any one of claims 1 to 4, characterized in that: The method further comprises: Before operating the target object, an image of the target object is obtained by a visual sensor, and the operation trajectory is obtained based on the obtained image analysis; and / or, When it is determined that an abnormality occurs, the robot is controlled to stop running.

9. A constant force control device for a robot, characterized in that: The device comprises: A first calculation module is used to obtain the external force on the end of the robot when the end of the robot is in the current first posture during the robot's operation on the target object, and calculate the target position adjustment amount according to the preset target constant force, the target position adjustment direction and the external force, wherein the first position in the first posture is the position currently moved to based on the preset operation trajectory; A second calculation module is used to obtain a target angle adjustment amount in a preset posture adjustment control direction corresponding to the external force torque applied to the robot end in the first posture, wherein the target angle adjustment amount is used to make the tool of the robot end after adjustment fit with the surface of the target object, and a target angle adjustment amount in a posture adjustment control direction is used to indicate a rotation angle adjustment amount in a rotation direction; A processing module, used for adjusting the first posture according to the target position adjustment amount and the target angle adjustment amount to obtain a second posture at a next moment; A control module is used to control the movement of the robot according to the second posture.

10. An electronic device, characterized in that: It comprises a processor and a memory, wherein the memory stores machine executable instructions that can be executed by the processor, and the processor can execute the machine executable instructions to implement the constant force control method of the robot as described in any one of claims 1-8.

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