Drag teaching speed limiting method, device, electronic equipment and medium for mechanical arm joints

Abstract

The present invention discloses a method for teaching and limiting speed of a mechanical arm joint, comprising: obtaining the actual dragging speed of the joint; when the actual dragging speed exceeds the preset safe dragging speed; calculating the adjustment torque of the joint motor through a dynamic model, the direction of the adjustment torque is opposite to the current movement direction of the joint; converting the adjustment torque into a motion control instruction of the joint motor, and sending it to the joint motor. The method for teaching and limiting speed of a mechanical arm joint proposed by the present invention, when the mechanical arm is dragged and taught, if the actual dragging speed of the joint exceeds the safe dragging speed, the joint motor will generate resistance in the opposite direction of the dragging to reduce the dragging speed of the mechanical arm joint, prevent the mechanical arm joint from being dragged too fast, and avoid safety risks caused by excessive speed. In addition, the present invention also discloses a device for teaching and limiting speed of a mechanical arm joint, an electronic device, and a medium.

Description

[0001] This case is a divisional application, the parent case application number is CN202110759410.4, the application date is 2021-07-06, and the case name is "Drag teaching speed limit method, device, electronic equipment and medium for robotic arm joints". Technical Field

[0002] The present invention relates to the field of mechanical arms, and in particular to a method, device, electronic equipment and medium for dragging, teaching and limiting speed of mechanical arm joints. Background Art

[0003] Drag teaching, also known as manual teaching, is a method in which the operator directly completes the teaching programming of the robot arm by manually dragging. The robot arm can then trigger instructions to repeat the teaching trajectory based on external signals.

[0004] When dragging and teaching the robot arm, you need to click the teach button first to put the robot arm into the drag teaching mode. After the robot arm enters the drag teaching mode, the operator drags the robot arm to the desired position. During the dragging process, the robot arm will record and save its motion posture or motion trajectory in real time, thus completing the drag teaching process for the robot arm.

[0005] In the prior art, the robot is in the torque loop control mode. In the drag teaching mode, the motion state of the robot joint is determined by the motor output torque and the external drag torque. When the external drag torque is too large, the robot joint will be at a safety risk due to the excessive speed. In addition, when the robot joint moves quickly due to being dragged, even if the external drag torque is stopped, the dynamic model of the robot joint will generate a force to maintain the current motion. Therefore, the robot joint will continue to move a certain distance at the current speed, and there will be safety risks in this process. Summary of the invention

[0006] The main purpose of the present invention is to propose a dragging teaching speed limiting method for a robot arm joint, aiming to solve the safety risk problem caused by excessive speed when the existing robot arm joint is dragging teaching.

[0007] To achieve the above object, the present invention proposes a drag teaching speed limiting method for a robot arm joint, comprising:

[0008] Get the actual drag speed of the joint;

[0009] When the actual dragging speed exceeds the preset safe dragging speed;

[0010] The adjustment torque of the joint motor is calculated through the dynamic model, and the direction of the adjustment torque is opposite to the current movement direction of the joint;

[0011] The adjustment torque is converted into motion control instructions for the joint motor and sent to the joint motor.

[0012] Among them, the drag teaching speed limit method of the robot arm joint also includes:

[0013] Set the velocity threshold of the joints when the robot arm is performing drag teaching;

[0014] The set velocity threshold is synthesized with the current movement direction of the joint to obtain the safe dragging speed of the joint.

[0015] Wherein, when the actual dragging speed is less than or equal to the safe dragging speed, the dragging teaching speed limiting method of the robot arm joint also includes:

[0016] Based on the dynamic model and the actual dragging speed of the joint, the theoretical torque of the joint is calculated;

[0017] Determine the torque constraint range of the joint according to the theoretical torque of the joint and its current velocity direction;

[0018] The output torque is saturated and adjusted according to the torque constraint range.

[0019] Among them, according to the theoretical torque of the joint and its current velocity direction, the torque constraint range of the joint is determined to include:

[0020] If the directions of the theoretical torque and the actual drag velocity are both positive, the torque constraint range of the joint is determined to be [0, T1];

[0021] If the directions of the theoretical torque and the actual drag speed are both negative, the torque constraint range of the joint is determined to be [-T1, 0];

[0022] If the direction of the theoretical torque is positive and the direction of the actual drag velocity is negative, the torque constraint range of the joint is determined to be [T1, T2];

[0023] If the direction of the theoretical torque is negative and the direction of the actual drag velocity is positive, the torque constraint range of the joint is determined to be [-T2, -T1];

[0024] T1 is the theoretical torque of the joint, T2 is the rated torque of the joint motor, T1 is less than T2 and both T1 and T2 are positive values, and the positive and negative directions of the torque and speed are referenced to the zero point of the joint.

[0025] Wherein, saturation adjustment of the output torque according to the torque constraint range includes:

[0026] When the torque constraint range of the joint is [0, T1] and the direction of the output torque is positive: if the output torque is greater than T1, the output torque is adjusted to T1; if the output torque is less than or equal to T1, there is no need to adjust the output torque;

[0027] When the torque constraint range of the joint is [-T1, 0] and the direction of the output torque is negative: if the output torque is greater than -T1, there is no need to adjust the output torque; if the output torque is less than or equal to -T1, adjust the output torque to -T1;

[0028] When the torque constraint range of the joint is [T1, T2] and the direction of the output torque is positive: if the output torque is greater than T1 and less than T2, there is no need to adjust the output torque; if the output torque is less than T1, adjust the output torque to T1; if the output torque is greater than T2, adjust the output torque to T2;

[0029] When the torque constraint range of the joint is [-T2, -T1] and the direction of the output torque is negative: if the output torque is greater than -T2 and less than -T1, there is no need to adjust the output torque; if the output torque is less than -T2, adjust the output torque to -T2; if the output torque is greater than -T1, adjust the output torque to -T1.

[0030] The present invention also provides a drag teaching speed limiting device for a mechanical arm joint, comprising:

[0031] The speed acquisition module is used to obtain the actual dragging speed of the joint;

[0032] The adjustment torque module is used to calculate the adjustment torque of the joint motor through the dynamic model when the actual dragging speed exceeds the preset safe dragging speed. The direction of the adjustment torque is opposite to the current movement direction of the joint;

[0033] The command generation module is used to convert the adjustment torque into the motion control command of the joint motor and send it to the joint motor.

[0034] Among them, the drag teaching speed limiting device of the robot arm joint also includes:

[0035] The rate setting module is used to set the rate threshold of the joints when the robot arm is performing drag teaching;

[0036] The speed synthesis module is used to synthesize the set rate threshold with the current movement direction of the joint to obtain the safe dragging speed of the joint.

[0037] Among them, the drag teaching speed limiting device of the robot arm joint also includes:

[0038] Theoretical torque module, used to calculate the theoretical torque of the joint based on the dynamic model and the actual drag speed of the joint;

[0039] The torque constraint module is used to determine the torque constraint range of the joint according to the theoretical torque of the joint and its current velocity direction;

[0040] The torque regulation module is used to perform saturation regulation on the output torque according to the torque constraint range.

[0041] The present invention also provides an electronic device, comprising:

[0042] Memory for storing computer programs;

[0043] The processor is used to implement the aforementioned dragging teaching speed limiting method of the mechanical arm joint when executing the computer program, and the dragging teaching speed limiting method of the mechanical arm joint at least comprises the following steps:

[0044] Get the actual drag speed of the joint;

[0045] When the actual dragging speed exceeds the preset safe dragging speed;

[0046] The adjustment torque of the joint motor is calculated through the dynamic model, and the direction of the adjustment torque is opposite to the current movement direction of the joint;

[0047] The adjustment torque is converted into motion control instructions for the joint motor and sent to the joint motor.

[0048] The present invention further provides a medium storing a computer program. When the computer program is executed by a processor, the aforementioned dragging teaching speed limiting method of a mechanical arm joint is implemented. The dragging teaching speed limiting method of a mechanical arm joint comprises at least the following steps:

[0049] Get the actual drag speed of the joint;

[0050] When the actual dragging speed exceeds the preset safe dragging speed;

[0051] The adjustment torque of the joint motor is calculated through the dynamic model, and the direction of the adjustment torque is opposite to the current movement direction of the joint;

[0052] The adjustment torque is converted into motion control instructions for the joint motor and sent to the joint motor.

[0053] Compared with the prior art, the beneficial technical effects of the embodiments of the present invention are:

[0054] When the robot arm is dragged and taught, first determine whether the actual drag speed of each joint of the robot arm exceeds its preset safe drag speed, wherein each robot arm joint corresponds to a preset safe drag speed. If it does not exceed the safe drag speed, there is no need to limit the speed of the robot arm joint. If it exceeds the safe drag speed, the adjustment torque of the joint motor of the robot arm joint is calculated through the dynamic model. The direction of the adjustment torque is opposite to the current movement direction (drag direction) of the joint. The reverse adjustment torque will cause the joint motor to generate resistance opposite to the drag direction, thereby reducing the drag speed of the robot arm joint, preventing the drag speed of the robot arm joint from being too fast, and avoiding safety risks caused by excessive speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 It is a schematic flow chart of a method for dragging and teaching speed limiting of a robot arm joint in one embodiment of the present invention;

[0056] Figure 2 Schematic diagram of joint speed limit in one embodiment of the present invention;

[0057] Figure 3 It is a schematic flow chart of a method for dragging and teaching speed limiting of a robot arm joint in one embodiment of the present invention;

[0058] Figure 4 It is a structural schematic diagram of a dragging teaching speed limiting device for a mechanical arm joint in one embodiment of the present invention;

[0059] Figure 5 It is a structural schematic diagram of a dragging teaching speed limiting device for a robot arm joint in one embodiment of the present invention. DETAILED DESCRIPTION

[0060] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but are not to be construed as limiting the present invention. All other embodiments obtained by ordinary technicians in the field without creative work based on the embodiments of the present invention are within the scope of protection of the present invention.

[0061] The dragging teaching speed limiting method of the mechanical arm joint proposed in the present invention is applicable to multi-joint robots, such as three-axis joint robots, four-axis joint robots, five-axis joint robots, six-axis joint robots and seven-axis joint robots. The multi-joint robot includes a main controller and a plurality of joints respectively connected to the main controller for communication. Each joint is provided with a joint controller, a joint motor and an encoder and other components. The encoder includes a code disk and a reader. The code disk is mounted on the motor shaft of the joint motor and rotates with the motor shaft. The reader is used to read the data on the code disk and send it to the joint controller or the main controller, so that the joint controller or the main controller can calculate the rotation speed and position of the joint according to the received data, that is, the rotation speed of the joint can be detected in real time through the encoder.

[0062] When a multi-joint robot is performing dragging teaching, safety risks may occur due to excessive dragging speed. For this reason, the present invention now proposes a dragging teaching speed limiting method for a robot arm joint, so that when the actual dragging speed of each joint exceeds the safe dragging speed, the joint motor of the joint generates an adjustment torque opposite to its dragging direction to limit the dragging speed of the joint, thereby preventing the dragging speed of the joint from being too fast, that is, it is equivalent to applying a resistance to the joint that is dragged at an overspeed.

[0063] See also Figure 1 , Figure 1 The flowchart of the dragging teaching speed limiting method of the robot arm joint in one embodiment of the present invention includes the following steps:

[0064] S10, obtaining the actual dragging speed of the joint;

[0065] In this embodiment, the dragging speed of the joint refers to its speed in the joint space, which is actually the rotation speed of the joint motor. The speed direction of the joint motor is based on its forward and reverse rotation. For example, forward rotation of the joint motor is the positive direction, and reverse rotation of the joint motor is the reverse direction.

[0066] The actual drag speed of a joint refers to the speed of the joint motor when it rotates. The actual drag speed of each joint of the robot arm is different. Take the six-axis robot arm as an example. Assuming that the actual drag speed of the first joint of the six-axis robot arm is 30° / s, the actual drag speed of the second joint may be 35° / s, the actual drag speed of the third joint may be 40° / s, the actual drag speed of the fourth joint may be 45° / s, the actual drag speed of the fifth joint may be 50° / s, and the actual drag speed of the sixth joint may be 60° / s.

[0067] When performing dragging teaching, the encoder of each joint first detects the rotation data of the joint motor, and then the joint controller of the corresponding joint processes the rotation data to calculate the rotation speed of the joint motor, that is, the actual drag speed of the joint, and then sends the calculated actual drag speed of the joint to the main controller of the robot. In addition, the rotation data detected by the encoder can also be directly sent to the main controller, so that the main controller can calculate the actual drag speed of the joint based on the rotation data.

[0068] S20, when the actual dragging speed exceeds the preset safe dragging speed, the adjustment torque of the joint motor is calculated through the dynamic model, and the direction of the adjustment torque is opposite to the current movement direction of the joint;

[0069] In some embodiments, after obtaining the actual dragging speed of the joint, it is determined whether the speed of the joint needs to be limited based on the actual dragging speed and the corresponding safe dragging speed. Specifically, if the actual dragging speed exceeds the preset safe dragging speed, the speed of the joint needs to be limited, and if the actual dragging speed does not exceed the preset safe dragging speed, the speed of the joint does not need to be limited.

[0070] Since the actual dragging speeds of each joint of the robotic arm are different, when teaching the robotic arm to drag, it is necessary to limit the speed of each joint separately so that the actual dragging speed of each joint is less than its respective safe dragging speed. If the actual dragging speed of any joint exceeds its preset safe dragging speed, the robotic arm will still have the safety risk issues mentioned above.

[0071] In addition, it should be noted that the safe dragging speeds of each joint are also different. Taking the six-axis robotic arm as an example, assuming that the safe dragging speed threshold of the first joint is 40° / s, the safe dragging speed threshold of the second joint may be 45° / s, the safe dragging speed threshold of the third joint is 50° / s, the safe dragging speed threshold of the fourth joint is 55° / s, the safe dragging speed threshold of the fifth joint is 60° / s, and the safe dragging speed threshold of the sixth joint is 70° / s.

[0072] See also Figure 2 , Figure 2 Schematic diagram of the speed limit of the robot arm joint in one embodiment of the present invention.

[0073] In this embodiment, when the actual dragging speed exceeds the safe dragging speed, the adjustment torque of the joint motor is calculated by the dynamic model, wherein the direction of the adjustment torque is opposite to the current movement direction (dragging direction) of the joint. Figure 2 The resultant force shown in is the resultant force of the drag torque and the adjustment torque.

[0074] S30, converting the adjustment torque into a motion control instruction of the joint motor and sending it to the joint motor.

[0075] The adjustment torque is converted into motion control instructions for the joint motor. According to the control instructions, the joint motor generates resistance in the opposite direction of the joint dragging direction, so as to reduce the actual dragging speed of the joint through the resistance, thereby achieving the purpose of speed limiting, thereby improving the safety of the robot arm during dragging teaching.

[0076] Specific application: Drag the robot arm to teach it to drag. During the dragging process, the encoder of each joint will detect the rotation data of the corresponding joint motor in real time, and then the joint controller or the main controller will process this rotation data to calculate the rotation speed of the joint motor, that is, the actual dragging speed of the joint. Assuming that the actual dragging speed of one of the joints is +45° / s, the corresponding safe dragging speed is +40° / s, + indicates that the joint motor of the joint is rotating forward (assuming that the forward rotation is the positive direction), that is, the rotation direction of the joint motor, and 45° / s indicates the rotation speed of the joint motor, that is, the joint motor rotates 45° per second. At this time, the actual dragging speed of the joint is +45° / s, which is greater than the safe dragging speed of the joint +40° / s. At this time, the adjustment torque of a joint motor is calculated by the dynamic model. The direction of the adjustment torque is opposite to the rotation direction of the joint motor. Assume that the calculated adjustment torque is -60N. After the adjustment torque is calculated, the adjustment torque is converted into a motion control instruction of the joint motor. The joint motor controls the rotation of the joint motor according to the motion control instruction, so that the speed of the joint motor is reduced under the action of the adjustment torque. Specifically, the rotation speed of the joint motor can be reduced to less than +40° / s, thereby preventing the dragging speed of the joint from being too fast, avoiding safety risks, and improving the safety of the robot arm during dragging teaching.

[0077] Furthermore, before limiting the speed of each joint of the robot arm, the safe dragging speed of each joint needs to be set first. The speed of the safe dragging speed is set according to the actual situation, and the speed direction of the safe dragging speed is the same as the current movement direction (dragging direction) of the joint.

[0078] For details, see Figure 3 , Figure 3 The flowchart of the dragging teaching speed limiting method of the robot arm joint in one embodiment of the present invention includes the following steps:

[0079] S1, sets the velocity threshold of the joint when the robot arm performs drag teaching;

[0080] S2, synthesize the set rate threshold with the current movement direction of the joint to obtain the safe dragging speed of the joint during drag teaching.

[0081] Each joint has a corresponding rate threshold, which is the maximum drag rate of the joint. After setting the rate threshold, the encoder is used to obtain the current movement direction (drag direction) of the joint, and then the rate threshold is combined with the movement direction of the joint to obtain the safe drag speed of the joint. The movement direction of the joint is based on the zero point of the joint. Assuming that the joint motor is rotating forward (clockwise) as the positive direction, the joint motor is rotating backward (counterclockwise) as the negative direction. The zero point here is equivalent to the origin of the two-dimensional rectangular coordinate system.

[0082] Example: Assume that the rate threshold of a joint of the robot arm is set to 50° / s. If the encoder detects that the current movement direction of the joint is positive, the synthesized safe dragging speed is +50° / s. If the encoder detects that the current movement direction of the joint is negative, the synthesized safe dragging speed is -50° / s.

[0083] Furthermore, the movement of the robot arm is generated by the combined action of the external drag torque and the output torque of the joint motor. When each joint of the robot arm moves, the dynamic model will calculate a theoretical torque to maintain the current movement of each joint, that is: external drag torque + output torque = theoretical torque. In order to ensure the controllability of the robot arm, the output torque of the joint motor cannot exceed the theoretical torque calculated by the dynamic model. If the output torque of the joint motor exceeds the theoretical torque, then when the drag stops (the external drag torque is zero), since the output torque of the joint motor is greater than the theoretical torque, the joint will still move under the combined force of the two and cannot stop when the hand is released, which is prone to safety risks.

[0084] To this end, the present invention constrains the output torque of the joint motor of each joint so that the output torque of the joint motor is smaller than the theoretical torque calculated by the dynamic model.

[0085] For details, see Figure 3 , Figure 3 This is a flow chart of a method for teaching speed limiting by dragging a robot arm in an embodiment of the present invention, comprising the following steps:

[0086] S40, calculating the theoretical torque of the joint based on the dynamic model and the actual dragging speed of the joint;

[0087] When the actual dragging speed of the joint is less than or equal to the safe dragging speed, the theoretical torque of the joint can be calculated based on the dynamic model and the actual dragging speed.

[0088] S50, determining a torque constraint range of the joint according to the theoretical torque of the joint and its current velocity direction;

[0089] After calculating the theoretical torque of the joint, the torque constraint range of the joint is determined based on the theoretical torque of the joint and the current speed direction. The theoretical torque and speed direction are based on the zero point calibration direction of the joint, which is specifically explained in the previous embodiment and will not be repeated here.

[0090] S60: saturation-regulate the output torque according to the torque constraint range.

[0091] After determining the torque constraint range, the output torque is saturated and adjusted according to the torque constraint range, so that the output torque of the joint motor is always smaller than the theoretical torque, thereby ensuring that the joints of the robot arm can stop moving after letting go.

[0092] Example: Assuming that the torque constraint range determined after steps S40 and S50 is [0, 100], if it is assumed that the output torque calculated next time is 80N, there is no need to adjust the output torque, and the output torque can be directly converted into the motion control instruction of the joint motor. If it is assumed that the output torque calculated next time is 110N, then the output torque needs to be adjusted to 100 N at this time, and then the adjusted output torque is converted into the motion control instruction of the joint.

[0093] Furthermore, the specific method for determining the torque constraint range proposed by the present invention is as follows:

[0094] If the directions of the theoretical torque and the actual drag velocity are both positive, the torque constraint range of the joint is determined to be [0, T1];

[0095] If the directions of the theoretical torque and the actual drag speed are both negative, the torque constraint range of the joint is determined to be [-T1, 0];

[0096] If the direction of the theoretical torque is positive and the direction of the actual drag velocity is negative, the torque constraint range of the joint is determined to be [T1, T2];

[0097] If the direction of the theoretical torque is negative and the direction of the actual drag velocity is positive, the torque constraint range of the joint is determined to be [-T2, -T1];

[0098] Wherein, T1 is the theoretical torque of the joint, T2 is the rated torque of the servo motor, T1 is less than T2 and both T1 and T2 are positive values, and the positive and negative directions of the torque and speed are referenced to the zero point of the joint.

[0099] Example: Assuming T1 is 100N, T2 is 150N, the actual drag speed is 50° / s, the joint motor forward rotation (clockwise rotation) is the positive direction, and the joint motor reverse rotation (counterclockwise rotation) is the reverse direction. First determine the direction of the theoretical torque and the actual drag speed, and then determine the torque constraint range of the joint according to the direction of the theoretical torque and the actual drag speed.

[0100] Specifically, if the theoretical torque is +100N and the actual drag speed is +50° / s, the torque constraint range of the joint is determined to be [0, 100]; if the theoretical torque is -100N and the actual drag speed is -50° / s, the torque constraint range of the joint is determined to be [-100, 0]; if the theoretical torque is +100N and the actual drag speed is -50° / s, the torque constraint range of the joint is determined to be [100, 150]; if the theoretical torque is -100N and the actual drag speed is +50° / s, the torque constraint range of the joint is determined to be [-150, -100].

[0101] Furthermore, the specific method for adjusting the output torque proposed by the present invention is as follows:

[0102] When the torque constraint range of the joint is [0, T1] and the output torque is positive: if the output torque is greater than T1, the output torque is adjusted to T1; if the output torque is less than or equal to T1, there is no need to adjust the output torque;

[0103] When the torque constraint range of the joint is [-T1, 0] and the output torque is negative: if the output torque is greater than -T1, there is no need to adjust the output torque; if the output torque is less than or equal to -T1, adjust the output torque to -T1;

[0104] When the torque constraint range of the joint is [T1, T2] and the output torque is positive: if the output torque is greater than T1 and less than T2, there is no need to adjust the output torque; if the output torque is less than T1, adjust the output torque to T1; if the output torque is greater than T2, adjust the output torque to T2;

[0105] When the torque constraint range of the joint is [-T2, -T1] and the output torque is negative: if the output torque is greater than -T2 and less than -T1, there is no need to adjust the output torque; if the output torque is less than -T2, adjust the output torque to -T2; if the output torque is greater than -T1, adjust the output torque to -T1.

[0106] Example: Assuming T1 is 100N, T2 is 150N, the actual drag speed is 50° / s, the joint motor forward rotation (clockwise rotation) is the positive direction, and the joint motor reverse rotation (counterclockwise rotation) is the reverse direction. First determine the direction of the theoretical torque and the actual drag speed, and then determine the torque constraint range of the joint according to the direction of the theoretical torque and the actual drag speed. Then adjust the output torque calculated next time according to the torque constraint range. Specifically:

[0107] When the torque constraint range of the joint is [0, 100] and the direction of the output torque is positive:

[0108] If the output torque calculated next time is +120N, then adjust the output torque to +100N. If the output torque calculated next time is +90N, then there is no need to adjust the output torque.

[0109] When the torque constraint range of the joint is [-100, 0] and the direction of the output torque is negative:

[0110] If the output torque calculated next time is -90N, there is no need to adjust the output torque. If the output torque calculated next time is -120N, adjust the output torque to -100.

[0111] When the torque constraint range of the joint is [100, 150] and the direction of the output torque is positive:

[0112] If the output torque calculated next time is +120N, there is no need to adjust the output torque. If the output torque calculated next time is 90N, adjust the output torque to 100N. If the output torque calculated next time is 160N, adjust the output torque to 150N.

[0113] When the torque constraint range of the joint is [-150, -100] and the direction of the output torque is negative:

[0114] If the output torque calculated next time is -120N, there is no need to adjust the output torque. If the output torque calculated next time is -90N, adjust the output torque to -100N. If the output torque calculated next time is -160N, adjust the output torque to -150N.

[0115] See also Figure 4 , Figure 4 The structure diagram of the dragging teaching speed limiting device of the robot arm joint in one embodiment of the present invention comprises:

[0116] The speed acquisition module 10 is used to acquire the actual dragging speed of the joint;

[0117] The adjustment torque module 20 is used to calculate the adjustment torque of the joint motor through the dynamic model when the actual dragging speed exceeds the preset safe dragging speed, and the direction of the adjustment torque is opposite to the current movement direction of the joint;

[0118] The instruction generation module 30 is used to convert the adjustment torque into a motion control instruction of the joint motor and send it to the joint motor.

[0119] Furthermore, the dragging teaching speed limiting device for the mechanical arm joint proposed by the present invention also includes:

[0120] The rate setting module is used to set the rate threshold of the joints when the robot arm is performing drag teaching;

[0121] The speed synthesis module is used to synthesize the set rate threshold with the current movement direction of the joint to obtain the safe dragging speed of the joint during drag teaching.

[0122] See also Figure 5 , Figure 5 The schematic diagram of the structure of the mechanical arm dragging teaching speed limiting device in one embodiment of the present invention also includes:

[0123] Theoretical torque module 40, used for calculating the theoretical torque of the joint based on the dynamic model and the actual dragging speed of the joint;

[0124] The torque constraint module 50 is used to determine the torque constraint range of the joint according to the theoretical torque of the joint and its current velocity direction;

[0125] The torque adjustment module 60 is used to perform saturation adjustment on the output torque according to the torque constraint range.

[0126] Based on the aforementioned dragging teaching speed limiting method for a mechanical arm joint, the present invention further proposes an electronic device, which includes:

[0127] Memory for storing computer programs;

[0128] The processor is used to implement the dragging teaching speed limiting method of the mechanical arm joint recorded in the above-mentioned embodiments when executing the computer program, and the dragging teaching speed limiting method of the mechanical arm joint at least comprises the following steps:

[0129] Step 1, obtain the actual dragging speed of the joint;

[0130] Step 2: when the actual dragging speed exceeds the preset safe dragging speed, the adjustment torque of the joint motor is calculated through the dynamic model, and the direction of the adjustment torque is opposite to the current movement direction of the joint;

[0131] Step 3, convert the adjustment torque into a motion control instruction of the joint motor and send it to the joint motor.

[0132] Based on the aforementioned dragging teaching speed limiting method for a mechanical arm joint, the present invention further proposes a medium storing a computer program. When the computer program is executed by a processor, the dragging teaching speed limiting method for a mechanical arm joint described in the aforementioned embodiments is implemented. The dragging teaching speed limiting method for a mechanical arm joint comprises at least the following steps:

[0133] Step 1, obtain the actual dragging speed of the joint;

[0134] Step 2: when the actual dragging speed exceeds the preset safe dragging speed, the adjustment torque of the joint motor is calculated through the dynamic model, and the direction of the adjustment torque is opposite to the current movement direction of the joint;

[0135] Step 3, convert the adjustment torque into a motion control instruction of the joint motor and send it to the joint motor.

[0136] In the several embodiments provided in the present application, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or modules, which can be electrical, mechanical or other forms.

[0137] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed on multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0138] In addition, each functional module in each embodiment of the present invention may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module. The above integrated modules may be implemented in the form of hardware or in the form of software functional modules.

[0139] If the integrated module is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for 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 method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0140] The above description is only a partial or preferred embodiment of the present invention. Neither the text nor the drawings can limit the scope of protection of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the overall concept of the present invention, or direct / indirect application in other related technical fields are included in the scope of protection of the present invention.

Claims

1. A drag teaching control method for a robot arm joint, characterized in that: include: Get the speed of the joint motor; When the rotation speed of the joint motor is less than or equal to the preset safe drag speed, the theoretical torque of the joint motor is calculated based on the dynamic model and the rotation speed of the joint motor; Determining a torque constraint range of the joint motor according to the theoretical torque of the joint motor and the current speed direction of the joint motor; Determining that the output torque of the joint motor exceeds the torque constraint range of the joint motor; Adjusting the output torque of the joint motor according to the torque constraint range of the joint motor; Determining the torque constraint range of the joint motor according to the theoretical torque of the joint motor and the current speed direction of the joint motor includes: If the theoretical torque of the joint motor and the speed direction of the joint motor are both positive, then the torque constraint range of the joint motor is determined to be [0, T1]; If the theoretical torque of the joint motor and the speed direction of the joint motor are both negative, then the torque constraint range of the joint motor is determined to be [-T1, 0]; If the direction of the theoretical torque of the joint motor is positive and the speed direction of the joint motor is negative, then the torque constraint range of the joint motor is determined to be [T1, T2]; If the direction of the theoretical torque of the joint motor is negative and the speed direction of the joint motor is positive, then the torque constraint range of the joint motor is determined to be [-T2, -T1]; Among them, T1 is the theoretical torque of the joint motor, T2 is the rated torque of the joint motor, T1 is less than T2 and both T1 and T2 are positive values, and the positive and negative directions of the theoretical torque, rated torque and speed of the joint motor are based on the zero point of the robotic arm joint.

2. The drag teaching control method of the robot arm joint according to claim 1 is characterized in that: The step of adjusting the output torque of the joint motor according to the torque constraint range of the joint motor includes: When the torque constraint range of the joint motor is [0, T1] and the direction of the output torque of the joint motor is positive: if the output torque of the joint motor is greater than T1, the output torque of the joint motor is adjusted to T1.

3. The drag teaching control method of the robot arm joint according to claim 1, characterized in that: The step of adjusting the output torque of the joint motor according to the torque constraint range of the joint motor includes: When the torque constraint range of the joint motor is [-T1, 0] and the direction of the output torque of the joint motor is negative: if the output torque of the joint motor is less than or equal to -T1, the output torque of the joint motor is adjusted to -T1.

4. The drag teaching control method of the robot arm joint according to claim 1, characterized in that: The step of adjusting the output torque of the joint motor according to the torque constraint range of the joint motor includes: When the torque constraint range of the joint motor is [T1, T2] and the direction of the output torque of the joint motor is positive: if the output torque of the joint motor is less than T1, the output torque of the joint motor is adjusted to T1; if the output torque of the joint motor is greater than T2, the output torque of the joint motor is adjusted to T2.

5. The drag teaching control method of the robot arm joint according to claim 1, characterized in that: The step of adjusting the output torque of the joint motor according to the torque constraint range of the joint motor includes: When the torque constraint range of the joint motor is [-T2, -T1] and the direction of the output torque is negative: if the output torque of the joint motor is less than -T2, the output torque of the joint motor is adjusted to -T2; if the output torque of the joint motor is greater than -T1, the output torque of the joint motor is adjusted to -T1.

6. A drag teaching control device for a robot arm joint, characterized in that: include: A memory for storing executable program instructions; A processor, wherein the processor executes the executable program instructions to perform the following steps: Get the speed of the joint motor; When the rotation speed of the joint motor is less than or equal to the preset safe drag speed, the theoretical torque of the joint motor is calculated based on the dynamic model and the rotation speed of the joint motor; Determining a torque constraint range of the joint motor according to the theoretical torque of the joint motor and the current speed direction of the joint motor; Determining that the output torque of the joint motor exceeds the torque constraint range of the joint motor; Adjusting the output torque of the joint motor according to the torque constraint range of the joint motor; Determining the torque constraint range of the joint motor according to the theoretical torque of the joint motor and the current speed direction of the joint motor includes: If the theoretical torque of the joint motor and the speed direction of the joint motor are both positive, then the torque constraint range of the joint motor is determined to be [0, T1]; If the theoretical torque of the joint motor and the speed direction of the joint motor are both negative, then the torque constraint range of the joint motor is determined to be [-T1, 0]; If the direction of the theoretical torque of the joint motor is positive and the speed direction of the joint motor is negative, then the torque constraint range of the joint motor is determined to be [T1, T2]; If the direction of the theoretical torque of the joint motor is negative and the speed direction of the joint motor is positive, then the torque constraint range of the joint motor is determined to be [-T2, -T1]; Among them, T1 is the theoretical torque of the joint motor, T2 is the rated torque of the joint motor, T1 is less than T2 and both T1 and T2 are positive values, and the positive and negative directions of the theoretical torque, rated torque and speed of the joint motor are based on the zero point of the robotic arm joint.

7. The drag teaching control device for the robot arm joint according to claim 6, characterized in that: When the processor executes the executable program instructions, the processor further performs the following steps: When the torque constraint range of the joint motor is [0, T1] and the direction of the output torque of the joint motor is positive: if the output torque of the joint motor is greater than T1, the output torque of the joint motor is adjusted to T1.

8. The dragging teaching control device for a robot arm joint according to claim 6, characterized in that: When the processor executes the executable program instructions, the processor further performs the following steps: When the torque constraint range of the joint motor is [-T1, 0] and the direction of the output torque of the joint motor is negative: if the output torque of the joint motor is less than or equal to -T1, the output torque of the joint motor is adjusted to -T1.

9. The dragging teaching control device for a robot arm joint according to claim 6, characterized in that: When the processor executes the executable program instructions, the processor further performs the following steps: When the torque constraint range of the joint motor is [T1, T2] and the direction of the output torque of the joint motor is positive: if the output torque of the joint motor is less than T1, the output torque of the joint motor is adjusted to T1; if the output torque of the joint motor is greater than T2, the output torque of the joint motor is adjusted to T2.

10. The dragging teaching control device for a robot arm joint according to claim 6, characterized in that: When the processor executes the executable program instructions, the processor further performs the following steps: When the torque constraint range of the joint motor is [-T2, -T1] and the direction of the output torque is negative: if the output torque of the joint motor is less than -T2, the output torque of the joint motor is adjusted to -T2; if the output torque of the joint motor is greater than -T1, the output torque of the joint motor is adjusted to -T1.

11. A readable storage medium, characterized in that: The readable storage medium stores executable program instructions, and when the executable program instructions are executed by the processor, the dragging teaching control method of the robot arm joint described in any one of claims 1-5 is implemented.

Images