Robot precision speed reducer performance test method, device and equipment

Abstract

The invention discloses a robot precision reducer performance test method, device and equipment, and relates to the technical field of robot detection, and the method comprises the steps: determining a target test joint of a precision reducer, and obtaining a standard test configuration of the target test joint based on a kinetic model of a robot; controlling a robot servo motor to implement a position keeping mode based on the standard test configuration, and determining a gravity torque reference of the standard test configuration; based on the gravity torque reference, an excitation joint adjacent to the target test joint is controlled to execute micro-amplitude high-frequency reciprocating motion under the standard test configuration, so that the target test joint generates a dynamic alternating torque load; torque feedback and angular displacement data of the target test joint under the action of the dynamic alternating torque load are synchronously collected, and a torque-rotation angle hysteretic curve is constructed after net excitation torque is calculated; and calculating the return difference and the torque rigidity of the precise speed reducer based on the torque-rotation angle hysteretic curve. And the speed reducer performance test under the real assembly boundary condition and the load coupling environment is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of robot detection, in particular to a robot precision reducer performance testing method, device and equipment. BACKGROUND

[0002] With the rapid development of high-end equipment manufacturing industry such as industrial robots, collaborative robots and humanoid robots, the performance of precision reducers as the core transmission components directly affects the positioning accuracy, motion stability and service life of the whole machine. Therefore, accurate testing of the comprehensive performance (such as torsional stiffness and backlash) of the precision reducer has become a key link to ensure the quality and reliability of various robots.

[0003] At present, the performance testing of precision reducers in the industry mainly relies on special offline test benches. This kind of method needs to disassemble the reducer from the robot and install it on an independent test equipment, and then load and collect data through external driving devices. This testing method constitutes the mainstream technical means of current performance evaluation and extends to humanoid robot joint testing scenarios.

[0004] However, the existing technical solutions have inherent limitations. First, the boundary conditions such as installation stiffness and coaxiality on the test bench are significantly different from the actual assembly state of the reducer on the robot body, which leads to a mismatch between the dynamic performance test results (such as vibration and noise) and the actual performance under real working conditions, and the testing accuracy is difficult to guarantee. Second, offline testing cannot reproduce the dynamic coupling effects between the motor, coupling, bearing and other components during robot operation, and the test environment is too idealized to reflect the real performance of the reducer in complex system interactions, which is particularly prominent in the complex working conditions of multiple joint collaborative motion of humanoid robots. In addition, special test benches are expensive, and usually only one sample can be tested at a time, with low test throughput, which is difficult to meet the needs of large-scale production line testing or in-service regular monitoring, especially in the demand for parallel testing of multiple joints of humanoid robots and in-service regular monitoring. There are obvious deficiencies in testing efficiency and economy.

[0005] The above content is only used to assist in understanding the technical solutions of the present application, and does not represent the acknowledgement of the above content as prior art. SUMMARY

[0006] The main purpose of the present application is to provide a robot precision reducer performance testing method, device and equipment, which aims to solve the technical problem that special test benches cannot meet the needs of large-scale production line testing or in-service regular monitoring.

[0007] To achieve the above purpose, the present application provides a robot precision reducer performance testing method, which comprises: determining a target test joint of the precision reducer, obtaining a standard test configuration of the target test joint based on a dynamic model of the robot; controlling servo motors of the robot to implement a position holding mode based on the standard test configuration, and determining a gravity torque reference of the standard test configuration; controlling an excitation joint adjacent to the target test joint to perform a micro-amplitude high-frequency reciprocating motion in the standard test configuration based on the gravity torque reference, so as to generate a dynamic alternating torque load on the target test joint; synchronously collecting torque feedback and angular displacement data of the target test joint under the dynamic alternating torque load, calculating a net excitation torque, and constructing a torque-rotation hysteresis curve; calculating the back-lash and torque stiffness of the precision reducer based on the torque-rotation hysteresis curve.

[0008] In an embodiment, the step of obtaining the standard test configuration of the target test joint based on the dynamic model of the robot comprises: obtaining a target test scenario, determining key working poses of the robot based on a typical motion trajectory of the target test scenario; calling the dynamic model of the robot, and calculating a force Jacobian matrix at the key working poses based on the dynamic model; defining or generating a group of candidate test configurations based on load characteristics of the target test scenario within a target working area of the robot; for each candidate test configuration, calculating a torque amplification coefficient of the target test joint in the current configuration through the force Jacobian matrix; comparing the torque amplification coefficients corresponding to each candidate test configuration, and selecting the candidate test configuration with the largest torque amplification coefficient as the standard test configuration.

[0009] In an embodiment, the step of controlling servo motors of the robot to implement a position holding mode based on the standard test configuration, and determining a gravity torque reference of the standard test configuration comprises: switching the control mode of the servo motor of each joint of the robot to a position holding mode, and locking the robot in the standard test configuration through the output torque of each joint servo motor, wherein the position holding mode is a zero-speed closed-loop control mode; continuously monitoring the deviation between the actual position and the command position of each joint servo motor, and if the position deviation of each joint is less than a preset stability threshold and is maintained for more than a preset stability time, it is determined that the system enters a static stable state; in the static stable state, synchronously reading and recording the real-time output torque feedback value of each joint servo motor through a high-speed real-time industrial bus; The real-time output torque feedback value of each joint servo motor is stored as a corresponding gravity torque reference value set under the current standard test configuration.

[0010] In an embodiment, before the step of controlling the excitation joint adjacent to the target test joint to perform a micro-amplitude high-frequency reciprocating motion under the standard test configuration based on the gravity torque reference, the method further comprises: determining a selection criterion of the excitation joint based on the motion characteristics of the target test scenario; defining all joints directly connected to the target test joint through a connecting rod as a candidate excitation joint set based on the topological structure of the robot; calculating a coupling influence factor of each joint in the candidate excitation joint set on the target test joint based on the force Jacobian matrix of the robot under the standard test configuration; calculating an equivalent motion inertia of each joint in the candidate excitation joint set under the standard test configuration; screening the candidate excitation joint with the highest coupling influence factor and the lowest equivalent motion inertia as the final excitation joint based on the coupling influence factor and the equivalent motion inertia, and combining the selection criterion of the excitation joint.

[0011] In an embodiment, the step of controlling the excitation joint adjacent to the target test joint to perform a micro-amplitude high-frequency reciprocating motion under the standard test configuration based on the gravity torque reference comprises: determining an excitation parameter based on the load characteristics of the target test scenario and the dynamics model of the robot, the excitation parameter including one or more of the selected excitation joint, the waveform type of the excitation motion, the excitation amplitude, and the excitation frequency; wherein the excitation amplitude is within a preset micro-amplitude range; combining a total position command by superimposing a dynamic alternating angular displacement command defined by the excitation parameter on the static position command corresponding to the gravity torque reference of the excitation joint; injecting the total position command into the servo motor of the excitation joint to drive the excitation joint to perform a micro-amplitude high-frequency reciprocating motion in accordance with the load characteristics; monitoring the instantaneous output torque of the target test joint and the excitation joint in real time; comparing the instantaneous output torque with a preset safety threshold based on the target test scenario, wherein the preset safety threshold is calculated by the gravity torque reference and the dynamics model; if the instantaneous output torque of any joint continuously exceeds the preset safety threshold, triggering a safety mechanism to stop the injection of the total position command.

[0012] In an embodiment, the step of constructing the torque-angle hysteresis curve after synchronously collecting the torque feedback and the angular displacement data of the target test joint under the dynamic alternating torque load, and calculating the net excitation torque comprises: After the micro-amplitude high-frequency reciprocating motion enters a stable state, synchronously collecting a measured output torque time sequence of the target test joint, an angular displacement time sequence fed back by a high-resolution absolute encoder of the target test joint, and an actual position feedback value of the excitation joint; Subtracting the measured output torque time sequence synchronously collected from the pre-stored gravity torque reference value point by point to obtain a net excitation torque time sequence generated by the micro-amplitude high-frequency reciprocating motion; Taking the actual position feedback value of the excitation joint as a reference benchmark, screening the net excitation torque data and the angular displacement data containing a complete excitation cycle from the net excitation torque time sequence and the angular displacement time sequence; Taking the screened angular displacement data as the X-axis and the corresponding net excitation torque data as the Y-axis, a scatter plot is drawn in the coordinate system and connected in time sequence to form a dynamic torque-angle hysteresis curve of the precision reducer.

[0013] In an embodiment, the step of calculating the back-lash of the precision reducer based on the torque-angle hysteresis curve comprises: Positioning an interval where the net excitation torque is zero on the torque-angle hysteresis curve; In the interval where the net excitation torque is zero, calculating the angular displacement values corresponding to the torque-angle hysteresis curve on the uplink path where the torque changes from negative to positive and the downlink path where the torque changes from positive to negative; Based on the absolute difference between the angular displacement values of the uplink path and the downlink path, the back-lash of the precision reducer is obtained.

[0014] In an embodiment, the step of calculating the torque stiffness of the precision reducer based on the torque-angle hysteresis curve comprises: Screening the linear sections with the highest linearity in the uplink path and the downlink path on the torque-angle hysteresis curve; Performing linear regression analysis on the screened linear sections of the uplink path and the downlink path to calculate the uplink path slope and the downlink path slope; Based on the arithmetic mean of the uplink path slope and the downlink path slope, the torque stiffness of the precision reducer is obtained.

[0015] In addition, to achieve the above-mentioned purpose, the present application also provides a robot precision reducer performance testing device, which comprises: a test configuration planning module configured to determine a target test joint of the precision reducer, and obtain a standard test configuration of the target test joint based on a dynamic model of the robot; a gravity compensation reference module configured to control a servo motor of the robot to implement a position holding mode based on the standard test configuration, and determine a gravity torque reference of the standard test configuration; an excitation load generation module configured to control an excitation joint adjacent to the target test joint to perform a micro high-frequency reciprocating motion in the standard test configuration based on the gravity torque reference, so as to generate a dynamic alternating torque load on the target test joint; a first data processing module configured to synchronously collect torque feedback and angular displacement data of the target test joint under the dynamic alternating torque load, and construct a torque-rotation hysteresis curve after calculating a net excitation torque; a second data processing module configured to calculate the back-lash and torque stiffness of the precision reducer based on the torque-rotation hysteresis curve.

[0016] In addition, to achieve the above object, the present application further provides a robot precision reducer performance testing device, which comprises a memory, a processor and a computer program stored in the memory and executable on the processor, and the computer program is configured to implement the steps of the robot precision reducer performance testing method as described above.

[0017] In addition, to achieve the above object, the present application further provides a storage medium, which is a computer readable storage medium, and the storage medium stores a computer program, and the computer program is executed by a processor to implement the steps of the robot precision reducer performance testing method as described above.

[0018] In addition, to achieve the above object, the present application further provides a computer program product, which comprises a computer program, and the computer program is executed by a processor to implement the steps of the robot precision reducer performance testing method as described above.

[0019] The one or more technical solutions provided by the present application have at least the following technical effects: The application determines a target test joint of the precision reducer, obtains a standard test configuration of the target test joint based on a dynamic model of the robot, controls a servo motor of the robot to implement a position holding mode based on the standard test configuration, determines a gravity torque reference of the standard test configuration, controls an adjacent excitation joint of the target test joint to perform a micro-amplitude high-frequency reciprocating motion under the standard test configuration based on the gravity torque reference, so that the target test joint generates a dynamic alternating torque load, synchronously collects torque feedback and angular displacement data of the target test joint under the dynamic alternating torque load, calculates a net excitation torque, and constructs a torque-angle hysteresis curve. The back-lash and torque stiffness of the precision reducer are calculated based on the torque-angle hysteresis curve. The performance test of the reducer under real assembly boundary conditions and load coupling environment is realized. BRIEF DESCRIPTION OF DRAWINGS

[0020] The drawings incorporated in and forming a part of the specification, illustrate preferred embodiments of the present application and, together with the description, serve to explain the principles of the present application.

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without any creative effort.

[0022] Figure 1 A flowchart provided for the robot precision reducer performance test method embodiment one of the present application; Figure 2 A flowchart provided for the robot precision reducer performance test method embodiment two of the present application; Figure 3 A flowchart provided for the robot precision reducer performance test method embodiment three of the present application; Figure 4 A flowchart provided for the robot precision reducer performance test method embodiment four of the present application; Figure 5 A module structure diagram of the robot precision reducer performance test device of the embodiment of the present application; Figure 6 A device structure diagram of the hardware running environment involved in the robot precision reducer performance test method in the embodiment of the present application.

[0023] The object implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the drawings. DETAILED DESCRIPTION

[0024] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application, and are not used to limit the present application.

[0025] For better understanding of the technical solutions of the present application, the following will be described in detail in conjunction with the drawings of the specification and specific embodiments.

[0026] Because the special test bench in the prior art cannot meet the needs of off-line detection under mass production or periodic monitoring in service.

[0027] The present application provides a solution, by determining the target test joint of the precision reducer, obtaining the standard test configuration of the target test joint based on the dynamics model of the robot; based on the standard test configuration, controlling the robot servo motor to implement the position keeping mode, determining the gravity torque reference of the standard test configuration; based on the gravity torque reference, controlling the adjacent excitation joint of the target test joint to perform the micro-amplitude high-frequency reciprocating motion under the standard test configuration, so as to make the target test joint generate dynamic alternating torque load; synchronously collecting the torque feedback and angular displacement data of the target test joint under the action of the dynamic alternating torque load, calculating the net excitation torque, and then constructing the torque-rotation angle hysteresis curve; based on the torque-rotation angle hysteresis curve, calculating the back-lash and torque stiffness of the precision reducer. The performance test of the reducer under the real assembly boundary condition and load coupling environment is realized.

[0028] Based on this, the present application provides a robot precision reducer performance test method, which is described with reference to Figure 1 , Figure 1 The flowchart of the first embodiment of the robot precision reducer performance test method of the present application is shown.

[0029] In this embodiment, the robot precision reducer performance test method comprises steps S10-S50: Step S10, determining the target test joint of the precision reducer, and obtaining the standard test configuration of the target test joint based on the dynamics model of the robot; It should be noted that in the present application, the target test joint refers to a specific joint in the robot where the precision reducer to be tested is installed. The standard test configuration refers to the overall posture selected for testing, in which each joint of the robot is at a specific angle value. The dynamics model of the robot refers to a mathematical model containing the kinematic parameters (such as link length, joint axis length) and inertia parameters (such as mass, center of mass, inertia tensor) of the robot. The test system proves by solving the force Jacobian matrix in the dynamics model, calculates the transmission relationship of the external force to the torque of each joint under different robot configurations, and selects a configuration that maximizes the torque amplification coefficient of the target test joint as the standard test configuration, the purpose is to produce the largest test torque on the target test joint with the smallest external excitation energy, and to improve the sensitivity and signal-to-noise ratio of the test.

[0030] Step S20, based on the standard test configuration, control the robot servo motor to implement a position holding mode, and determine a gravity torque reference of the standard test configuration; It should be noted that in the embodiments of the present application, the position holding mode refers to a control mode of the servo driver, at this time the motor will be strictly locked at the given command position, and output the necessary torque to resist external force (such as gravity), which is usually realized by zero speed closed loop control. The gravity torque reference refers to a set of steady state torque values output by the servo motor to balance the gravity of the robot body acting on each joint in the standard test configuration, which accurately measures and deducts the influence of gravity on torque measurement, and establishes a pure torque measurement reference.

[0031] Step S30, based on the gravity torque reference, control the excitation joint adjacent to the target test joint to perform a small amplitude high frequency reciprocating motion in the standard test configuration, so as to generate a dynamic alternating torque load on the target test joint; It should be noted that in the embodiments of the present application, the excitation joint refers to the adjacent joint which is kinematically precisely coupled with the target test joint and is actively controlled to generate excitation motion. The small amplitude high frequency reciprocating motion refers to a periodic angular change with an amplitude less than 1 degree and a frequency in the range of 1-10 Hz, for example, a sine wave motion. The dynamic alternating torque load refers to a torque which periodically changes in size and direction over time. Without the aid of external equipment, a real load for testing is generated inside the robot system. The test system utilizes the force mapping relationship in robot dynamics to accurately control the excitation joint to perform a small amplitude high frequency reciprocating motion near the locked position which has been compensated for gravity. Through the transmission of the linkage mechanism, the motion excites a pure dynamic and calculable dynamic alternating torque load on the target test joint.

[0032] Optionally, the test system will monitor the feedback torque of the target test joint and the excitation joint in real time. The system presets a safety threshold based on the dynamics model and the gravity torque reference, and once the torque is detected to be out of limit, the excitation motion is immediately stopped to prevent overload damage to the robot.

[0033] Step S40, synchronously collect torque feedback and angular displacement data of the target test joint under the action of the dynamic alternating torque load, calculate the net excitation torque, and construct a torque-rotation hysteresis curve; It should be noted that in the embodiments of the present application, the torque feedback comes from the real-time torque output value of the target test joint servo driver. The angular displacement data refers to the high-resolution encoder feedback value installed on the motor side and the load side of the target test joint. The net excitation torque refers to the dynamic torque component generated by the excitation motion after deducting the gravity torque reference from the total torque of the test. The torque-angle hysteresis curve is a closed curve representing the comprehensive characteristics of the reducer under positive and negative loads, such as transmission stiffness, friction loss, and backlash, plotted with angular displacement as the horizontal coordinate and net excitation torque as the vertical coordinate.

[0034] In step S50, the backlash and torque stiffness of the precision reducer are calculated based on the torque-angle hysteresis curve.

[0035] It should be noted that in the embodiments of the present application, the backlash value refers to the maximum difference in angular displacement corresponding to the hysteresis curve in the positive and negative torque directions near zero torque, reflecting the transmission idle travel caused by factors such as internal gear meshing clearance and elastic deformation of the reducer. The torque stiffness refers to a quantitative indicator of the reducer's resistance to torsional deformation, which is the ratio of the torque change to the corresponding angular displacement change, i.e., the slope of the linear segment of the hysteresis curve.

[0036] The embodiments abandon the traditional offline testing paradigm that relies on expensive special-purpose benches, and embed the testing function in the robot control system. By utilizing the robot's own dynamic characteristics, accurate and controllable dynamic test loads are generated in real assembly boundary and load coupling environment. Based on high-precision data synchronous acquisition and processing, the performance parameters of the precision reducer are evaluated, significantly improving the realism of the test results to the actual working conditions, and greatly reducing the test cost and complexity.

[0037] Further, with reference to Figure 2 The second embodiment of the robot precision reducer performance testing method provides a flowchart, based on the above Figure 2 The step of "obtaining the standard test configuration of the target test joint based on the dynamic model of the robot" in step S10 is further refined, including steps A201-A205: Step A201, obtain the target test scene, and determine the key working poses of the robot based on the typical motion trajectory of the target test scene; It should be noted that in the embodiments of the present application, the target test scene refers to a specific working condition environment of the robot in actual application, including but not limited to walking on flat ground, going up and down stairs, load carrying and other specific work tasks; the typical motion trajectory refers to the standard motion path most commonly executed by each joint of the humanoid robot in the target test scene, especially the motion law of the lower limb joints in the gait cycle; the key working pose refers to the robot configuration state that has the greatest influence on the dynamic characteristics of the robot and is the most representative in the typical motion trajectory. The test system extracts the typical motion trajectory by analyzing the gait planning data or actual motion record of the humanoid robot, and determines the key working pose that needs to be tested in depth based on the characteristic phase in the gait cycle (such as the single-foot support middle period, the double-foot support conversion period, etc.).

[0038] In a specific embodiment, for the dynamic walking test scene of the humanoid robot, the test system analyzes the gait cycle thereof, selects the posture when the right leg single-foot support middle period and the knee joint flexion angle reach the maximum value, and the posture when the ground reaction force reaches the peak value in the process of converting from single-foot support to double-foot support, and determines the two typical poses as the key working poses of the test.

[0039] Step A202, calling a dynamic model of the robot, and calculating a force Jacobian matrix at the key working pose based on the dynamic model; It should be noted that in the embodiments of the present application, the dynamic model of the robot refers to a complete mathematical model containing all kinematic parameters (such as link length, joint bias) and dynamic parameters (such as mass, inertia tensor, center of mass position) of the robot; the force Jacobian matrix refers to the device matrix of the Jacobian matrix describing the force / speed mapping relationship between the space of the end effector of the robot and the joint space, which represents the linear transformation relationship between the generalized force acting on the end effector and the required output torque of each joint under the condition of static balance.

[0040] Optionally, the dynamic model can be directly established based on the CAD model parameters; the calculation of the force Jacobian matrix can be realized by using the differential transformation method or the vector product method in standard robotics. Specifically, the test system calculates the 6x6 force Jacobian matrix at a certain key working pose by using the vector product method based on the pre-calibrated D-H parameters and link inertia parameters. Each element J_ij of the matrix accurately reflects the contribution degree of the jth operating space force / torque component to the ith joint torque.

[0041] Step A203, defining or generating a set of candidate test configurations in the target working area of the robot based on the load characteristics of the target test scene; It should be noted that in the embodiments of the present application, the target working area refers to a specific motion range frequently used in actual work of the robot or having higher performance requirements; the load characteristic refers to the size, direction and variation law of the load borne by the robot; and the candidate test configuration refers to a group of joint angle combinations of the robot preselected for systematic test comparison. The test system generates a group of candidate test configurations based on the boundary conditions of the target working area and the distribution law of the load characteristic, using a systematic sampling method such as a uniform grid method, a random sampling method or a sampling method based on task probability.

[0042] In a specific embodiment, for the test scene of the palletizing robot, the test system generates 200 different joint angle combinations in the maximum working space thereof using the uniform grid method, each combination ensuring that the posture of the robot is stable and the torque of each joint is within the rated range, and these combinations constitute the candidate test configuration set.

[0043] Step A204, for each candidate test configuration, calculating the torque amplification coefficient of the target test joint in the current configuration through the force Jacobian matrix; It should be noted that in the embodiments of the present application, the torque amplification coefficient refers to an index for quantitatively evaluating the excitation efficiency in a specific configuration, which is specifically defined as: when a unit generalized force is applied at the end of the robot, the equivalent torque that can be generated on the target test joint. This coefficient is usually obtained by calculating the norm of the row vector corresponding to the target test joint in the force Jacobian matrix.

[0044] In a specific embodiment, if the target test joint is joint 3, the system calculates the 2-norm of the third row vector of the force Jacobian matrix J for each candidate configuration, and then takes the reciprocal of the norm as the torque amplification coefficient of joint 3 in the current configuration, that is, the coefficient = 1 / ||J(3, :)||2, wherein J represents the force Jacobian matrix, (3, :) represents taking the third row of the matrix; and ||...||2 is the 2-norm calculation of the vector. The larger the coefficient is, the greater the torque response that the motion of the excitation joint can generate on the target test joint in this configuration.

[0045] Step A205, comparing the torque amplification coefficients corresponding to each candidate test configuration, and selecting the candidate test configuration with the largest torque amplification coefficient as the standard test configuration.

[0046] It should be noted that in the embodiments of the present application, the standard test configuration refers to a specific robot posture determined after systematic comparison and optimization, which makes the torque amplification coefficient of the target test joint reach a global or local maximum value, ensuring the highest excitation efficiency and test sensitivity in the test process.

[0047] Optionally, the test system records all joint angle coordinates of the standard test configuration and sets them as the fixed initial state of the test procedure to ensure consistency and repeatability of the test conditions.

[0048] In one possible implementation, the step of determining the gravity torque reference of the standard test configuration based on the standard test configuration includes: switching the control mode of each joint servo motor of the robot to a position holding mode, and locking the robot in the standard test configuration by outputting torque through each joint servo motor, wherein the position holding mode is a zero speed closed loop control mode; continuously monitoring the deviation of the actual position from the command position of each joint servo motor, and determining that the system enters a static stable state if the position deviation of each joint is less than a preset stability threshold and is maintained for more than a preset stability time; in the static stable state, synchronously reading and recording the real-time output torque feedback value of each joint servo motor through a high-speed real-time industrial bus; storing the real-time output torque feedback value of each joint servo motor as a corresponding gravity torque reference value set under the current standard test configuration.

[0049] It should be noted that in the embodiments of the present application, the position holding mode refers to a control mode of a servo driver, in which the motor strictly maintains a given position command and generates necessary resistance torque through closed loop control to keep the position constant; the zero speed closed loop control mode is a specific way to realize position holding, and the control target is to maintain the motor speed at zero; the static stable state refers to a system state in which the deviation of the actual position from the command position of each joint of the robot is continuously within an extremely small range and is stable; and the gravity torque reference value set refers to a complete set of steady state torque values output by each joint servo motor to balance the gravity of the robot body under a specific configuration.

[0050] The embodiments switch all joint servo motors to the position holding mode to rigidly lock the robot as a whole, then determine whether the system reaches complete static balance by continuously monitoring the position deviation, and after confirming that the stable state is reached, synchronously collect the torque data of each joint through a high-speed real-time industrial bus and store them as standardized gravity torque references.

[0051] In one possible implementation, the high-speed real-time industrial bus can use an industrial Ethernet protocol such as EtherCAT, PROFINET IRT or SERCOS III that has the characteristics of determinacy and time synchronization to ensure the synchronization accuracy of data collection. The stability threshold can be set to within 0.001 radian according to the accuracy requirement of the robot, and the stability time can be set to 0.5-2 seconds according to the response characteristics of the system.

[0052] In a specific embodiment, the robot control system switches all joint servo drives of the six-axis robot to position holding mode, and continuously monitors the position deviation of all six joints. When the position deviation of all joints is less than 0.0008 rad and remains stable for 1.2 seconds, the system is determined to be in a static stable state. At this time, the real-time torque feedback values of the six servo drives [15.2 Nm, -8.7 Nm, 22.3 Nm, 1.5 Nm, 0.8 Nm, 0.2 Nm] are read synchronously through the EtherCAT bus, and this set of values is stored as the gravity torque reference value set under the current standard test configuration.

[0053] In a possible embodiment, before the step of controlling the excitation joints adjacent to the target test joint to perform a small-amplitude high-frequency reciprocating motion under the standard test configuration based on the gravity torque reference, so as to make the target test joint generate a dynamic alternating torque load, the method further comprises: determining a selection criterion for the excitation joints based on the motion characteristics of the target test scenario; defining all joints directly connected to the target test joint through a connecting rod as a candidate excitation joint set based on the topological structure of the robot; calculating a coupling influence factor of each joint in the candidate excitation joint set on the target test joint under the standard test configuration based on the force Jacobian matrix of the robot; calculating the equivalent motion inertia of each joint in the candidate excitation joint set under the standard test configuration; based on the coupling influence factor and the equivalent motion inertia, combining the selection criterion of the excitation joints, and screening the candidate excitation joint with the highest coupling influence factor higher than a preset coupling threshold and the lowest equivalent motion inertia as the final excitation joint.

[0054] It should be noted that in the embodiment, the motion characteristics of the target test scene refer to the motion mode characteristics in the actual working environment of the robot, including motion speed, acceleration range, trajectory complexity, and dynamic response requirements; the selection criteria of the excitation joint refer to the joint optimization criteria formulated according to the test requirements, mainly considering the dynamic coupling efficiency and motion control accuracy; the coupling influence factor is used to represent the degree of influence of the candidate joint motion on the torque of the target test joint. The equivalent motion inertia refers to the equivalent motion inertia of the robot system mapped to the candidate joint axis under the standard test configuration. The preset coupling threshold refers to the minimum value of the coupling influence factor set to ensure the effectiveness of excitation. The embodiment determines the optimal excitation joint from all possible adjacent joints through quantitative analysis of the system, ensuring that the test process can efficiently generate dynamic alternating torque load with sufficient amplitude on the target test joint, and maximally reduces control energy consumption and improves system response speed.

[0055] Optionally, the coupling influence factor can be quantified by calculating the size of the reaction torque on the target test joint when the candidate joint generates a unit angular velocity; the equivalent motion inertia can be calculated by the mass matrix in the dynamics model of the robot. The selection criteria of the excitation joint can set different weight coefficients according to specific test requirements or test scenes to seek the optimal balance between coupling strength and motion inertia. The preset coupling threshold can be set according to specific application requirements, such as 60% of the maximum coupling influence factor.

[0056] Further, with reference to Figure 3 , the third embodiment of the robot precision reducer performance test method of the application provides a flowchart, based on the above Figure 3 embodiment, the step of "controlling the excitation joint adjacent to the target test joint to perform micro-amplitude high-frequency reciprocating motion under the standard test configuration based on the gravity torque reference" in step S30 is further refined, including steps A301-A306: Step A301, determining excitation parameters based on the load characteristics of the target test scene and the dynamics model of the robot, the excitation parameters including one or more of the selected excitation joint, the waveform type of excitation motion, the excitation amplitude, and the excitation frequency; wherein the excitation amplitude is within a preset micro-amplitude range; It should be noted that in the embodiments of the present application, the load characteristics of the target test scene refer to the load characteristics borne by the robot in the actual working environment, including load size, direction, change law and dynamic response requirement; the excitation parameters refer to a set of configurable variables required to control the excitation joint to generate a specific motion mode; the waveform type of the excitation motion refers to a function form describing the change law of the angle of the excitation joint with time, such as a sine wave, a triangular wave or a square wave; the excitation amplitude refers to the maximum angular displacement of the excitation joint reciprocating around its balance position; the excitation frequency refers to the number of complete cycles of the excitation motion completed in a unit of time; and the preset micro-amplitude range refers to an angle change interval set to ensure that the overall configuration of the robot does not change significantly during the test, which is usually less than ±1 degree. By establishing an excitation parameter system matched with the target test scene, it is ensured that the generated dynamic load meets the test requirements and guarantees system safety.

[0057] In step A302, a total position command is synthesized by superimposing a dynamic alternating angular displacement command defined by the excitation parameters on a static position command corresponding to the gravity torque reference of the excitation joint. It should be noted that in the embodiments of the present application, the static position command refers to an angle command value that causes the excitation joint to stabilize at the balance position under the labeled test configuration; the dynamic alternating unique command refers to a time-varying angle command component determined by the excitation parameters; and the total position command refers to the linear superposition result of the static position command and the dynamic alternating angular displacement command.

[0058] Optionally, the static position command of the excitation joint after gravity compensation is θ0=1.2 radian, the dynamic alternating angular displacement command is θ1(t)=0.01sin(10πt) radian (corresponding to ±0.57 degrees, 5Hz sine motion), and the synthesized total position command is θ_cmd(t)=1.2+0.01sin(10πt) radian.

[0059] In step A303, the total position command is injected into the servo motor of the excitation joint to drive the excitation joint to perform a micro-amplitude high-frequency reciprocating motion meeting the load characteristics. It should be noted that in the embodiments of the present application, the generated total position command is sent to the servo driver through a real-time communication bus. The micro-amplitude high-frequency reciprocating motion meeting the load characteristics refers to the periodic angular change of the excitation joint according to the synthesized command trajectory, which matches the load characteristics of the target test scene. The micro-amplitude high-frequency reciprocating motion refers to the periodic angular change of the excitation joint according to the synthesized command trajectory. By accurately executing the preset excitation motion mode, a stable and reliable dynamic load source is provided for the test.

[0060] In step A304, the instantaneous output torque of the target test joint and the excitation joint is monitored in real time. It should be noted that in the embodiments of the present application, the instantaneous output torque refers to the current output torque instantaneous value fed back by the servo driver in real time.

[0061] Step A305, comparing the instantaneous output torque with a preset safety threshold based on the target test scenario, wherein the preset safety threshold is calculated by the gravity torque reference and the dynamics model; It should be noted that in the embodiments of the present application, the preset safety threshold based on the target test scenario refers to the torque safety upper limit value set according to the safety requirements of the specific test scenario. The test system calculates the safety working threshold of each joint based on the gravity torque reference value and the possible torque fluctuation range predicted by the dynamics model, and continuously compares the real-time monitored instantaneous output torque with the threshold. For example, for the target test joint, the preset safety threshold is set to 150% of its gravity torque reference value, and for the excitation joint, the preset safety threshold is set to 120% of its gravity torque reference value.

[0062] Step A306, if the instantaneous output torque of any joint continuously exceeds the preset safety threshold, triggering a safety mechanism to stop the injection of the total position command.

[0063] It should be noted that in the embodiments of the present application, when the monitoring system detects that the instantaneous output torque of any joint exceeds its corresponding preset safety threshold and the duration exceeds a set value, the safety mechanism is triggered immediately, the sending of the excitation command is stopped, and all joints are switched to a safe state to prevent equipment damage.

[0064] The embodiment converts the generation of dynamic load into a reliable operation with parameterization, predictability and inherent safety fault tolerance. Through parameter initialization based on the dynamics model, the scientificity and optimality of the excitation motion are ensured; through command synthesis and injection, accurate generation of dynamic load and stable maintenance of the overall configuration of the robot are realized; and real-time torque monitoring and automatic safety stop mechanism build an active protection system, effectively avoiding the risk of overload and ensuring the safety of the equipment and the reliability of the process during dynamic testing on real robots.

[0065] Further, with reference to Figure 4 The fourth embodiment of the robot precision reducer performance test method of the present application provides a flowchart, which is based on the above-mentioned Figure 4 The step of "synchronously collecting torque feedback and angular displacement data of the target test joint under the action of the dynamic alternating torque load, and constructing a torque-rotation hysteresis curve after calculating the net excitation torque" in step S40 is further refined, including steps A401-A404. Step A401, after the micro-amplitude high-frequency reciprocating motion enters a stable state, synchronously collecting a measured output torque time sequence of the target test joint, an angular displacement time sequence fed back by a high-resolution absolute encoder of the target test joint, and an actual position feedback value of the excitation joint; It should be noted that in the embodiments of the present application, the measured output torque time sequence refers to time sequence data composed of a group of instantaneous torque values continuously fed back by the servo driver of the target test joint at fixed time intervals; the high-resolution absolute encoder is a precise angle sensor capable of directly reading mechanical position without accumulating pulses and having subdivision capability; the angular displacement time sequence refers to time sequence data composed of a group of instantaneous angle values continuously fed back by the high-resolution absolute encoder at fixed time intervals; and the actual position feedback value refers to the actual angular position of the rotor of the excitation joint servo system in real time. The test system starts the synchronous collection of multiple sensor channels through a unified hardware synchronous trigger signal, ensures that all time sequence data have strictly consistent time stamps, and eliminates the problem of asynchronous data caused by sampling time deviation.

[0066] Step A402, point-by-point subtracting the measured output torque time sequence synchronously collected from the pre-stored gravity torque reference value to obtain a net excitation torque time sequence generated by the micro-amplitude high-frequency reciprocating motion; It should be noted that in the embodiments of the present application, point-by-point subtraction refers to performing subtraction operation on each data point in the time sequence and the corresponding gravity torque reference value; and the net excitation torque time sequence refers to time sequence data composed of only dynamic torque components generated by excitation motion, which has eliminated the interference of gravity.

[0067] Step A403, taking the actual position feedback value of the excitation joint as a reference datum, screening the net excitation torque data and angular displacement data containing a complete excitation period from the net excitation torque time sequence and the angular displacement time sequence; It should be noted that in the embodiments of the present application, the complete excitation period refers to a data segment corresponding to one complete reciprocating motion (such as one complete 2π phase change of a sine wave) of the excitation joint, which excludes the interference of starting, stopping transient or unstable period, and ensures the accuracy of performance test.

[0068] Step A404, taking the screened angular displacement data as the X-axis and the corresponding net excitation torque data as the Y-axis, drawing a scatter plot in the coordinate system and connecting in time sequence to form a dynamic torque-rotation angle hysteresis curve of the precision reducer.

[0069] It should be noted that in the embodiments of the present application, the dynamic torque-angle hysteresis curve refers to a closed curve describing the non-linear relationship between the output torque and the input angle of the precision reducer under dynamic alternating load, which comprehensively reflects the stiffness, friction and clearance characteristics of the reducer, i.e. the time series data is converted into a characteristic graph that can intuitively and comprehensively characterize the dynamic transmission performance of the reducer.

[0070] The embodiments ensure the time consistency of the data through multi-channel synchronous acquisition, effectively eliminate the time shift error; the real dynamic response of the reducer is highlighted by calculating the net excitation torque; the effectiveness and representativeness of the analysis data are ensured through the periodic screening mechanism, and the interference of the transient process is excluded; finally, the complex dynamic transmission characteristics are converted into intuitive and quantifiable graphical representation, which significantly improves the accuracy and reliability of the test results.

[0071] In a possible implementation, the step of calculating the back-lash of the precision reducer based on the torque-angle hysteresis curve comprises: locating an interval where the net excitation torque is zero on the torque-angle hysteresis curve; calculating the angular displacement values corresponding to the uplink path where the torque changes from negative to positive and the downlink path where the torque changes from positive to negative on the torque-angle hysteresis curve in the interval where the net excitation torque is zero; obtaining the back-lash of the precision reducer based on the absolute difference between the angular displacement values of the uplink path and the downlink path.

[0072] It should be noted that in the embodiments of the present application, the uplink path refers to the trajectory part of the hysteresis curve where the torque changes from the negative value area to the positive value area; the downlink path refers to the trajectory part of the hysteresis curve where the torque changes from the positive value area to the negative value area; the back-lash refers to the transmission idle travel of the precision reducer due to internal gear meshing clearance, elastic deformation and other factors, which is quantified as the angular displacement difference value on the positive and negative transmission paths near zero torque. The embodiments accurately locate the zero torque interval on the hysteresis curve, then identify the corresponding angular displacement feature points of the uplink and downlink paths in the interval, and finally obtain the back-lash value by calculating the absolute difference between the two, effectively avoiding the subjective error of traditional visual reading, and realizing the objectivity and standardization of the test results.

[0073] Optionally, the zero torque interval can be defined as a continuous section where the torque value fluctuates in the range of [-ε, +ε], where ε is a small threshold close to zero; the angular displacement values corresponding to the uplink path and the downlink path can be determined by finding the intersection points of the two paths with the zero torque line in the interval, or calculating the average angular displacement of the two paths in the interval.

[0074] In a possible implementation, the step of calculating the torque stiffness of the precision reducer based on the torque-angle hysteresis curve comprises: selecting a section with the highest linearity in the uplink path and downlink path on the torque-angle hysteresis curve; performing linear regression analysis on the linear section of the uplink path and downlink path selected to obtain an uplink path slope and a downlink path slope; obtaining the torque stiffness of the precision reducer based on the arithmetic mean of the uplink path slope and the downlink path slope.

[0075] It should be noted that, in the embodiments of the present application, the section with the highest linearity refers to a continuous data interval in the uplink or downlink path of the torque-angle hysteresis curve, which has the closest data point distribution to a straight line and best reflects the linear elastic deformation characteristics of the reducer; the linear regression analysis refers to a statistical process of determining the slope and intercept of the best fitting straight line by linear fitting of data points through mathematical methods such as least squares method; the uplink path slope refers to the slope of the fitting straight line of the section in which the torque increases with the increase of the angle in the hysteresis curve; and the downlink path slope refers to the slope of the fitting straight line of the section in which the torque decreases with the decrease of the angle in the hysteresis curve. The embodiments automatically identify the section in the curve that best represents the linear stiffness characteristics, and use mathematical regression analysis to eliminate random errors, and finally obtain a more representative stiffness value through the average processing of the slopes of the two-way paths, thereby effectively improving the accuracy and repeatability of the stiffness calculation.

[0076] Optionally, the evaluation of the linearity can be achieved by calculating the coefficient of determination R² between the data points of each candidate section and the fitting straight line, and selecting the section with the R² closest to 1 as the section with the highest linearity; and the linear regression analysis can use the least squares method for linear fitting.

[0077] It should be noted that the above examples are only used for understanding the present application and do not constitute a limitation on the robot precision reducer performance test method of the present application, and more forms of simple transformation based on this technical concept are within the protection scope of the present application.

[0078] The present application also provides a robot precision reducer performance test device, which is described in detail in Figure 5 The robot precision reducer performance test device comprises: a test configuration planning module 10 configured to determine a target test joint of the precision reducer and obtain a standard test configuration of the target test joint based on a dynamics model of the robot; a gravity compensation reference module 20 configured to control the robot servo motor to implement a position holding mode based on the standard test configuration and determine a gravity torque reference of the standard test configuration; The excitation load generation module 30 is configured to control an excitation joint adjacent to the target test joint to perform a slight high-frequency reciprocating motion in the standard test configuration based on the gravity torque reference, so as to generate a dynamic alternating torque load on the target test joint. The first data processing module 40 is configured to synchronously collect torque feedback and angular displacement data of the target test joint under the dynamic alternating torque load, and to calculate a net excitation torque and construct a torque-angle hysteresis curve. The second data processing module 50 is configured to calculate the back-lash and torque stiffness of the precision reducer based on the torque-angle hysteresis curve.

[0079] The robot precision reducer performance testing device provided in the present application adopts the robot precision reducer performance testing method in the above embodiments, and can solve the technical problem that a special test bench cannot meet the needs of off-line detection in large-scale production or periodic monitoring in service. Compared with the prior art, the robot precision reducer performance testing device provided in the present application has the same beneficial effects as the robot precision reducer performance testing method provided in the above embodiments, and other technical features in the robot precision reducer performance testing device are the same as the features disclosed in the above embodiments, which will not be described here.

[0080] The present application provides a robot precision reducer performance testing device, which comprises at least one processor and a memory in communication connection with the at least one processor. The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the robot precision reducer performance testing method in Embodiment I.

[0081] Reference will now be made to the following description Figure 6 which shows a structural schematic diagram of a robot precision reducer performance testing device suitable for implementing the embodiments of the present application. The robot precision reducer performance testing device in the embodiments of the present application can include, but is not limited to, mobile terminals such as mobile phones, notebook computers, digital broadcast receivers, PDAs (Personal Digital Assistant), PADs (Portable Application Description), PMPs (Portable Multimedia Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), and the like, and fixed terminals such as digital TVs, desktop computers, and the like. Figure 6 The robot precision reducer performance testing device shown is merely an example, and should not impose any limitation on the functions and use range of the embodiments of the present application.

[0082] AsFigure 6 As shown, the robot precision reducer performance test equipment can include a processing device 1001 (e.g., a central processing unit, a graphics processing unit, etc.) that can perform various appropriate actions and processes according to programs stored in a read-only memory 1002 or programs loaded from a storage device 1003 into a random access memory 1004. Various programs and data required for the operation of the robot precision reducer performance test equipment are also stored in the random access memory 1004. The processing device 1001, the read-only memory 1002, and the random access memory 1004 are connected to each other through a bus 1005. An input / output interface 1006 is also connected to the bus. Generally, the following systems can be connected to the input / output interface 1006: input devices 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; the storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the robot precision reducer performance test equipment to communicate with other devices wirelessly or by wire to exchange data. Although the robot precision reducer performance test equipment with various systems is shown in the figure, it should be understood that all the systems shown are not required to be implemented or possessed. More or fewer systems can be alternatively implemented or possessed.

[0083] In particular, according to the embodiments disclosed in the present application, the processes described above with reference to the flowcharts can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product comprising a computer program carried on a computer readable medium, the computer program containing program codes for executing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network through the communication device, or installed from the storage device 1003, or installed from the read-only memory 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the methods of the embodiments disclosed in the present application are performed.

[0084] The robot precision reducer performance test equipment provided in the present application adopts the robot precision reducer performance test method in the above-mentioned embodiments, and can solve the technical problem that a special test bench cannot meet the needs of off-line detection under large-scale production or periodic monitoring in service. Compared with the prior art, the robot precision reducer performance test equipment provided in the present application has the same beneficial effects as the robot precision reducer performance test method provided in the above-mentioned embodiments, and other technical features in the robot precision reducer performance test equipment are the same as the features disclosed in the previous embodiment method, which will not be described here.

[0085] It should be understood that various aspects of the disclosure can be implemented in hardware, software, firmware, or a combination thereof. In the description of the embodiments above, specific features, structures, materials or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0086] The above description is merely illustrative of the application and is not intended to limit the scope of the application. Any variations and modifications that can be made by any person skilled in the art within the spirit and scope of the application are intended to be encompassed by the application. The scope of the application is defined by the appended claims.

[0087] The application provides a computer readable storage medium having stored thereon computer readable program instructions (i.e., a computer program) for performing the robot precision reducer performance testing method in the above-described embodiments.

[0088] The computer readable storage medium provided by the application may, for example, be a U disk, but is not limited to an electric, magnetic, optical, electromagnetic, infrared, or semiconductor system or device, or any combination thereof. More specific examples of the computer readable storage medium can include, but are not limited to, an electric connection having one or more conductive wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present embodiment, the computer readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system or device. The program code contained on the computer readable storage medium can be transmitted by any suitable medium, including but not limited to an electric wire, an optical cable, an RF (Radio Frequency), etc., or any suitable combination thereof.

[0089] The above-described computer readable storage medium can be contained in a robot precision reducer performance testing device; or can exist separately and not be assembled into a robot precision reducer performance testing device.

[0090] The computer readable storage medium described above carries one or more programs, when the one or more programs are executed by the robot precision reducer performance testing device, the robot precision reducer performance testing device is caused to: determine a target test joint of the precision reducer, obtain a standard test configuration of the target test joint based on a dynamics model of the robot; control the robot servo motor to implement a position holding mode based on the standard test configuration, determine a gravity torque benchmark of the standard test configuration; based on the gravity torque benchmark, control an excitation joint adjacent to the target test joint to perform a slight high-frequency reciprocating motion under the standard test configuration, so that the target test joint generates a dynamic alternating torque load; synchronously collect torque feedback and angular displacement data of the target test joint under the action of the dynamic alternating torque load, calculate a net excitation torque, and then construct a torque-angle hysteresis curve; and calculate the back-lash and torque stiffness of the precision reducer based on the torque-angle hysteresis curve.

[0091] Computer program code for carrying out operations of the present application can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0092] The flowcharts and block diagrams in the drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present application. In this regard, each block in the flowcharts or block diagrams can represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions noted in the blocks can occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently or the blocks can sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and / or flowchart illustrations, and combinations thereof, can be implemented by a dedicated hardware-based system that performs the specified functions or operations, or can be implemented by a combination of dedicated hardware and computer instructions.

[0093] The modules involved in the embodiments of the present application can be implemented in the form of software or in the form of hardware. In some cases, the names of the modules do not constitute a limitation on the modules themselves.

[0094] The readable storage medium provided by the present application is a computer readable storage medium, which stores computer readable program instructions (i.e., a computer program) for executing the robot precision reducer performance testing method described above, and can solve the technical problem that a special test bench cannot meet the needs of off-line detection in large-scale production or periodic monitoring in service. Compared with the prior art, the computer readable storage medium provided by the present application has the same beneficial effects as the robot precision reducer performance testing method provided by the above-mentioned embodiments, and will not be described here.

[0095] The present application also provides a computer program product comprising a computer program, which, when executed by a processor, implements the steps of the robot precision reducer performance testing method as described above.

[0096] The computer program product provided by the present application can solve the technical problem that a special test bench cannot meet the needs of off-line detection in large-scale production or periodic monitoring in service. Compared with the prior art, the computer program product provided by the present application has the same beneficial effects as the robot precision reducer performance testing method provided by the above-mentioned embodiments, and will not be described here.

[0097] The above only describes some embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent structural transformation made by using the content of the present application specification and drawings, or direct / indirect application in other related technical fields is included in the patent protection scope of the present application.

Claims

1. A method of testing performance of a robot precision reducer, characterized by, The robot precision reducer performance test method comprises: determining a target test joint of the precision reducer, obtaining a standard test configuration of the target test joint based on a dynamics model of the robot; controlling a servo motor of the robot to implement a position holding mode based on the standard test configuration, and determining a gravity torque reference of the standard test configuration; based on the gravity torque reference, controlling an excitation joint adjacent to the target test joint to perform a micro-amplitude high-frequency reciprocating motion under the standard test configuration, so that the target test joint generates a dynamic alternating torque load; synchronously collecting torque feedback and angular displacement data of the target test joint under the dynamic alternating torque load, calculating a net excitation torque, and constructing a torque-angle hysteresis curve; calculating the hysteresis and torque stiffness of the precision reducer based on the torque-angle hysteresis curve.

2. The robotic precision reducer performance testing method of claim 1, wherein, The step of obtaining the standard test configuration of the target test joint based on the dynamics model of the robot comprises: obtaining a target test scene, determining key working poses of the robot based on typical motion trajectories of the target test scene; calling the dynamics model of the robot, and calculating a force Jacobian matrix under the key working poses based on the dynamics model; defining or generating a set of candidate test configurations in the target working area of the robot based on the load characteristics of the target test scene; for each candidate test configuration, calculating a torque amplification coefficient of the target test joint under the current configuration through the force Jacobian matrix; comparing the torque amplification coefficients corresponding to each candidate test configuration, and selecting the candidate test configuration with the largest torque amplification coefficient as the standard test configuration.

3. The robotic precision reducer performance testing method of claim 2, wherein, The step of controlling the servo motor of the robot to implement the position holding mode based on the standard test configuration, and determining the gravity torque reference of the standard test configuration comprises: switching the control mode of the servo motor of each joint of the robot to the position holding mode, and locking the robot in the standard test configuration through the torque output of each joint servo motor, wherein the position holding mode is a zero-speed closed-loop control mode; continuously monitoring the deviation between the actual position and the command position of each joint servo motor, and if the position deviation of each joint is less than a preset stability threshold and is maintained for more than a preset stability time, it is determined that the system enters a static steady state; in the static steady state, synchronously reading and recording the real-time output torque feedback value of each joint servo motor through a high-speed real-time industrial bus; storing the real-time output torque feedback value of each joint servo motor as a set of gravity torque reference values corresponding to the current standard test configuration.

4. The robotic precision reducer performance testing method of claim 3, wherein, Before the step of controlling the excitation joint adjacent to the target test joint to perform a micro-amplitude high-frequency reciprocating motion under the standard test configuration based on the gravity torque reference, so that the target test joint generates a dynamic alternating torque load, the method further comprises: determining the selection criteria of the excitation joint based on the motion characteristics of the target test scene; based on the topological structure of the robot, defining all joints directly connected to the target test joint through connecting rods as a set of candidate excitation joints; In the standard test configuration, a coupling influence factor of each joint in the candidate excitation joint set on the target test joint is calculated based on a force Jacobian matrix of the robot; An equivalent motion inertia of each joint in the candidate excitation joint set in the standard test configuration is calculated; Based on the coupling influence factor and the equivalent motion inertia, combined with the selection criteria of the excitation joint, the candidate excitation joint with the highest coupling influence factor higher than a preset coupling threshold and the lowest equivalent motion inertia is selected as the final excitation joint.

5. The robotic precision reducer performance testing method of claim 4, wherein, The step of controlling the excitation joint adjacent to the target test joint to perform a micro-amplitude high-frequency reciprocating motion in the standard test configuration based on the gravity torque reference comprises: Based on the load characteristics of the target test scene and the dynamic model of the robot, determine the excitation parameters, which at least include one or more of the selected excitation joint, the waveform type of the excitation motion, the excitation amplitude and the excitation frequency; wherein the excitation amplitude is within a preset micro-amplitude range; By superimposing a dynamic alternating angular displacement command defined by the excitation parameters on the static position command corresponding to the gravity torque reference of the excitation joint, a total position command is synthesized; The total position command is injected into the servo motor of the excitation joint to drive the excitation joint to perform a micro-amplitude high-frequency reciprocating motion consistent with the load characteristics; The instantaneous output torque of the target test joint and the excitation joint is monitored in real time; The instantaneous output torque is compared with a preset safety threshold based on the target test scene, wherein the preset safety threshold is calculated by the gravity torque reference and the dynamic model; If the instantaneous output torque of any joint continuously exceeds the preset safety threshold, a safety mechanism is triggered to stop the injection of the total position command.

6. The robotic precision reducer performance testing method of claim 5, wherein, The step of synchronously collecting the torque feedback and angular displacement data of the target test joint under the action of the dynamic alternating torque load, calculating the net excitation torque, and constructing the torque-rotation angle hysteresis curve comprises: After the micro-amplitude high-frequency reciprocating motion enters a stable state, the measured output torque time series of the target test joint, the angular displacement time series fed back by the high-resolution absolute encoder of the target test joint, and the actual position feedback value of the excitation joint are synchronously collected; The measured output torque time series synchronously collected is point-by-point subtracted from the pre-stored gravity torque reference value to obtain a net excitation torque time series generated by the micro-amplitude high-frequency reciprocating motion; Taking the actual position feedback value of the excitation joint as a reference benchmark, the net excitation torque data and angular displacement data containing a complete excitation period are screened from the net excitation torque time series and the angular displacement time series; Taking the screened angular displacement data as the X-axis and the corresponding net excitation torque data as the Y-axis, a scatter plot is drawn in the coordinate system and connected in time sequence to form the dynamic torque-rotation angle hysteresis curve of the precision reducer.

7. The robotic precision reducer performance testing method of claim 6, wherein, The step of calculating the back-lash of the precision reducer based on the torque-rotation angle hysteresis curve comprises: Locating the interval where the net excitation torque is zero on the torque-rotation angle hysteresis curve; In the interval where the net excitation torque is zero, the angular displacement values corresponding to the uplink path where the torque changes from negative to positive and the downlink path where the torque changes from positive to negative on the torque-angle hysteresis curve are calculated; The absolute difference between the angular displacement values of the uplink path and the downlink path is obtained to obtain the back-lash of the precision reducer.

8. The robotic precision reducer performance testing method of claim 7, wherein, The step of calculating the torque stiffness of the precision reducer based on the torque-angle hysteresis curve comprises: Filtering the section with the highest linearity on the uplink path and the downlink path on the torque-angle hysteresis curve; Performing linear regression analysis on the linear section of the uplink path and the downlink path filtered to obtain the uplink path slope and the downlink path slope; The arithmetic mean of the uplink path slope and the downlink path slope is obtained to obtain the torque stiffness of the precision reducer.

9. A robot precision reducer performance testing device, characterized by, The robot precision reducer performance testing device comprises: A test configuration planning module for determining a target test joint of the precision reducer and obtaining a standard test configuration of the target test joint based on a dynamics model of the robot; A gravity compensation reference module for controlling the robot servo motor to implement a position holding mode based on the standard test configuration and determining a gravity torque reference of the standard test configuration; An excitation load generation module for controlling an excitation joint adjacent to the target test joint to perform a micro-amplitude high-frequency reciprocating motion in the standard test configuration based on the gravity torque reference, so as to generate a dynamic alternating torque load on the target test joint; A first data processing module for synchronously collecting torque feedback and angular displacement data of the target test joint under the action of the dynamic alternating torque load, calculating a net excitation torque, and constructing a torque-angle hysteresis curve; A second data processing module for calculating the back-lash and the torque stiffness of the precision reducer based on the torque-angle hysteresis curve.

10. A robotic precision reducer performance testing device apparatus, characterized by, The device comprises a memory, a processor, and a computer program stored on the memory and executable on the processor, and the computer program is configured to implement the steps of the robot precision reducer performance testing method according to any one of claims 1 to 8.

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