Method, device and equipment for testing performance of robot precision reducer

Abstract

The application discloses a robot precision reducer performance test method, device and equipment, and relates to the technical field of robot detection. The method comprises the following steps: determining a target test joint of a 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 keeping mode based on the standard test configuration, and determining a gravity torque benchmark of the standard test configuration; based on the gravity torque benchmark, controlling an adjacent excitation joint of 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 action of the dynamic alternating torque load, calculating a net excitation torque, and then constructing a torque-rotation angle hysteresis curve; and calculating the backlash and torque stiffness of the precision reducer based on the torque-rotation angle hysteresis curve. The performance test of the reducer 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 method requires the reducer to be disassembled from the robot and installed on an independent test device, and data is collected through external driving devices. This testing method constitutes the mainstream technology of current performance evaluation and extends to humanoid robot joint testing scenarios.

[0004] However, the existing technical solution has 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, resulting in 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, making it 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:

[0008] 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;

[0009] 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;

[0010] 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;

[0011] 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 angle hysteresis curve;

[0012] calculating the back-lash and torque stiffness of the precision reducer based on the torque-rotation angle hysteresis curve.

[0013] In an embodiment, the step of obtaining a standard test configuration of the target test joint based on a dynamics model of the robot comprises:

[0014] obtaining a target test scenario, and determining key working poses of the robot based on a typical motion trajectory of the target test scenario;

[0015] calling a dynamics model of the robot, and calculating a force Jacobian matrix at the key working poses based on the dynamics model;

[0016] defining or generating a set of candidate test configurations based on load characteristics of the target test scenario in a target working area of the robot;

[0017] for each candidate test configuration, calculating a torque amplification coefficient of the target test joint in the current configuration through the force Jacobian matrix;

[0018] comparing the torque amplification coefficients corresponding to each candidate test configuration, and selecting a candidate test configuration with the largest torque amplification coefficient as the standard test configuration.

[0019] 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:

[0020] 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 torque output of each joint servo motor, wherein the position holding mode is a zero-speed closed-loop control mode;

[0021] The deviation between the actual position and the command position of each joint servo motor is continuously monitored, 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;

[0022] In the static stable state, the real-time output torque feedback value of each joint servo motor is synchronously read and recorded through a high-speed real-time industrial bus;

[0023] 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.

[0024] In an embodiment, before the step of controlling the excitation joints 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:

[0025] Based on the motion characteristics of the target test scenario, a selection criterion for the excitation joints is determined;

[0026] Based on the topological structure of the robot, all joints directly connected to the target test joint through a connecting rod are defined as a candidate excitation joint set;

[0027] Under the standard test configuration, the coupling influence factor of each joint in the candidate excitation joint set on the target test joint is calculated based on the force Jacobian matrix of the robot;

[0028] The equivalent motion inertia of each joint in the candidate excitation joint set under the standard test configuration is calculated;

[0029] Based on the coupling influence factor and the equivalent motion inertia, combined with the selection criterion for the excitation joints, the candidate excitation joint with the highest coupling influence factor above a preset coupling threshold and the lowest equivalent motion inertia is selected as the final excitation joint.

[0030] In an embodiment, the step of controlling the excitation joints 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:

[0031] Based on the load characteristics of the target test scenario and the dynamics model of the robot, an excitation parameter is determined, the excitation parameter at least 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;

[0032] superimposing a dynamic alternating angular displacement instruction defined by the excitation parameter on the static position instruction corresponding to the gravity torque reference of the excitation joint to synthesize a total position instruction;

[0033] injecting the total position instruction into a 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;

[0034] real-time monitoring of the instantaneous output torque of the target test joint and the excitation joint;

[0035] 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 a dynamics model;

[0036] 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 instruction.

[0037] In an embodiment, 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 hysteresis curve includes:

[0038] after the micro-amplitude high-frequency reciprocating motion enters a steady state, synchronously collecting the measured output torque time series of the target test joint, the angular displacement time series of the high-resolution absolute encoder feedback of the target test joint, and the actual position feedback value of the excitation joint;

[0039] point-by-point subtracting the measured output torque time series synchronously collected 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;

[0040] taking the actual position feedback value of the excitation joint as a reference benchmark, screening the net excitation torque data and angular displacement data containing a complete excitation period from the net excitation torque time series and the angular displacement time series;

[0041] 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 the dynamic torque-rotation hysteresis curve of the precision reducer.

[0042] In an embodiment, the step of calculating the back-lash of the precision reducer based on the torque-rotation hysteresis curve includes:

[0043] positioning the interval where the net excitation torque is zero on the torque-rotation hysteresis curve;

[0044] 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;

[0045] The absolute difference between the angular displacement values of the uplink path and the downlink path is used to obtain the back-lash of the precision reducer.

[0046] In an embodiment, the step of calculating the torque stiffness of the precision reducer based on the torque-angle hysteresis curve comprises:

[0047] The linear sections with the highest linearity in the uplink path and the downlink path on the torque-angle hysteresis curve are screened;

[0048] Linear regression analysis is performed on the screened linear sections of the uplink path and the downlink path, and the uplink path slope and the downlink path slope are calculated;

[0049] The arithmetic mean of the uplink path slope and the downlink path slope is used to obtain the torque stiffness of the precision reducer.

[0050] In addition, to achieve the above-mentioned purpose, the present application also proposes a robot precision reducer performance testing device, which comprises:

[0051] A test configuration planning module is configured to determine a target test joint of a precision reducer, and obtain a standard test configuration of the target test joint based on a dynamics model of a robot;

[0052] A gravity compensation reference module is configured to control a 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;

[0053] An excitation load generation module is configured to control 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;

[0054] A first data processing module is configured to 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 construct a torque-angle hysteresis curve;

[0055] A second data processing module is configured to calculate the back-lash and the torque stiffness of the precision reducer based on the torque-angle hysteresis curve.

[0056] In addition, to achieve the above object, the present application also 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.

[0057] In addition, to achieve the above object, the present application also 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.

[0058] In addition, to achieve the above object, the present application also 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.

[0059] The one or more technical solutions provided by the present application have at least the following technical effects:

[0060] The present application determines the target test joint of the precision reducer, obtains the standard test configuration of the target test joint based on the dynamics model of the robot, controls the servo motor of the robot to implement the position keeping mode based on the standard test configuration, determines the gravity torque reference of the standard test configuration, controls the adjacent excitation joint of the target test joint to perform the micro-amplitude high-frequency reciprocating motion under the standard test configuration based on the gravity torque reference, so that the target test joint generates dynamic alternating torque load, synchronously collects the torque feedback and angular displacement data of the target test joint under the action of the dynamic alternating torque load, calculates the net excitation torque, and constructs the torque-rotation angle hysteresis curve. The back-lash and torque stiffness of the precision reducer are calculated based on the torque-rotation angle hysteresis curve. The reducer performance testing under the real assembly boundary condition and load coupling environment is realized. BRIEF DESCRIPTION OF DRAWINGS

[0061] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present application and serve to explain the principles of the present application together with the specification.

[0062] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings.

[0063] Figure 1 The flowchart provided by the robot precision reducer performance testing method embodiment one of the present application is shown in the figure;

[0064] Figure 2 The flowchart provided for the second embodiment of the robot precision reducer performance test method of the application;

[0065] Figure 3 The flowchart provided for the third embodiment of the robot precision reducer performance test method of the application;

[0066] Figure 4 The flowchart provided for the fourth embodiment of the robot precision reducer performance test method of the application;

[0067] Figure 5 The module structure diagram of the robot precision reducer performance test device of the embodiment of the application;

[0068] Figure 6 The device structure diagram of the hardware operating environment involved in the robot precision reducer performance test method in the embodiment of the application.

[0069] The purpose implementation, functional features and advantages of the application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0070] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the application and do not limit the application.

[0071] In order to better understand the technical solutions of the application, the following will be described in detail in combination with the drawings of the specification and specific embodiments.

[0072] Because the special test bench in the prior art cannot meet the needs of off-line detection under large-scale production or periodic monitoring in service.

[0073] The 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 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 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 reducer performance test under the real assembly boundary condition and load coupling environment is realized.

[0074] Based on this, the embodiment of the application provides a robot precision reducer performance test method, which is described with reference to Figure 1 , Figure 1A flowchart of a first embodiment of a robot precision reducer performance test method of the present application.

[0075] In this embodiment, the robot precision reducer performance test method comprises steps S10-S50:

[0076] Step S10, determine the target test joint of the precision reducer, and obtain the standard test configuration of the target test joint based on the dynamics model of the robot;

[0077] It should be noted that in the embodiments of 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 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 calculates the transmission relationship of the external force mapping to the torque of each joint under different robot configurations by solving the force Jacobian matrix in the dynamics model, and selects a configuration that maximizes the torque amplification factor of the target test joint as the standard test configuration. The purpose is to generate the largest test torque on the target test joint with the smallest external excitation energy, improving the sensitivity and signal-to-noise ratio of the test.

[0078] Step S20, based on the standard test configuration, control the servo motor of the robot to implement position holding mode, and determine the gravity torque reference of the standard test configuration;

[0079] 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 which time the motor will be strictly locked at the given command position and output the necessary torque to resist external forces (such as gravity), which is usually achieved through zero speed closed loop control. The gravity torque reference refers to a set of steady state torque values under the standard test configuration, in which the robot body gravity acts on each joint and is output by the servo motor to balance this gravity torque. The effect of gravity on torque measurement is accurately measured and deducted to establish a pure torque measurement reference.

[0080] Step S30, based on the gravity torque reference, control the excitation joint adjacent to the target test joint to perform micro-amplitude high-frequency reciprocating motion under the standard test configuration, so as to generate a dynamic alternating torque load on the target test joint;

[0081] It should be noted that in the embodiments of the present application, the excitation joint refers to an adjacent joint that is actively controlled to generate excitation motion and is kinematically precisely coupled with the target test joint. The micro-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 that periodically changes in size and direction over time. The real load for testing is generated internally in the robot system without the aid of external equipment. The test system utilizes the force mapping relationship in robot dynamics to precisely control the excitation joint to perform micro-amplitude high-frequency reciprocating motion near the locked position that has been compensated for gravity. Through the transmission of the linkage mechanism, the motion excites a pure dynamic, calculable dynamic alternating torque load on the target test joint.

[0082] Optionally, the test system monitors the feedback torque of the target test joint and the excitation joint in real time. The system sets a safety threshold based on the dynamic model and the gravity torque benchmark, and stops the excitation motion immediately once it detects that the torque exceeds the threshold, preventing overload damage to the robot.

[0083] 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-angle hysteresis curve;

[0084] 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 servo driver of the target test joint. The angular displacement data refers to the feedback values of high-resolution encoders 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 benchmark from the total torque of the test. The torque-angle hysteresis curve is a closed curve drawn with angular displacement as the horizontal coordinate and net excitation torque as the vertical coordinate, representing the transmission stiffness, friction loss, and backlash of the reducer under forward and reverse loads.

[0085] Step S50, calculate the backlash and torque stiffness of the precision reducer based on the torque-angle hysteresis curve.

[0086] 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 gear meshing clearance and elastic deformation inside the reducer. The torque stiffness refers to a quantitative indicator of the resistance to torsional deformation of the reducer, which is the ratio of the change in torque to the corresponding change in angular displacement, i.e., the slope of the linear segment of the hysteresis curve.

[0087] The embodiment discards the traditional offline test paradigm relying on expensive special-purpose test bench, embeds the test function in the robot control system, generates accurate controllable dynamic test load in a real assembly boundary and load coupling environment by utilizing the robot's own dynamic characteristics, and realizes the evaluation of the performance parameters of the precision reducer based on high-precision data synchronous acquisition and processing, which significantly improves the reflection authenticity of the test results to the actual working conditions and greatly reduces the test cost and complexity.

[0088] Further, with reference to Figure 2 , the second embodiment of the robot precision reducer performance test method of the application provides a flowchart, which is based on the embodiment shown in 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:

[0089] Step A201, obtaining a target test scene, determining the key working pose of the robot based on the typical motion trajectory of the target test scene;

[0090] It should be noted that in the embodiments of the 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 impact 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.).

[0091] 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 postures as the key working poses of the test.

[0092] Step A202, calling the dynamic model of the robot, calculating the force Jacobian matrix under the key working pose based on the dynamic model;

[0093] 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 a device matrix of the Jacobian matrix describing the force / speed mapping relationship between the end effector space and the joint space of the robot, representing 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.

[0094] 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 based on the pre-calibrated D-H parameters and link inertia parameters, and 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.

[0095] Step A203, in the target working area of the robot, a set of candidate test configurations is defined or generated based on the load characteristics of the target test scene;

[0096] It should be noted that in the embodiments of the present application, the target working area refers to a specific motion range frequently used or with higher performance requirements in the actual work of the robot; the load characteristics refer to the size, direction and variation law of the load borne by the robot; the candidate test configuration refers to a set of joint angle combinations of the robot pre-selected for systematic test comparison. The test system generates a set of candidate test configurations by using a systematic sampling method (such as uniform grid method, random sampling method or sampling method based on task probability) based on the boundary conditions and the distribution law of the load characteristics of the target working area.

[0097] In a specific embodiment, for the test scene of the palletizing robot, the test system generates 200 different joint angle combinations in its maximum working space by using the uniform grid method, each combination ensures that the attitude 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.

[0098] Step A204, for each candidate test configuration, the torque amplification coefficient of the target test joint under the current configuration is calculated through the force Jacobian matrix;

[0099] 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 under 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.

[0100] 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 inverse of the norm as the torque amplification coefficient of joint 3 in the current configuration, i.e., the coefficient = 1 / ||J(3,:)||2, where J represents the force Jacobian matrix, (3,:) represents taking the third row of the matrix; ||...||2 is the 2-norm calculation of the vector. The larger the coefficient, the greater the torque response that can be generated on the target test joint by exciting the joint movement in this configuration.

[0101] Step A205, compare the torque amplification coefficients corresponding to each of the candidate test configurations, and select the candidate test configuration with the largest torque amplification coefficient as the standard test configuration.

[0102] It should be noted that in the embodiments of the present application, the standard test configuration refers to a specific robot pose 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 during the test process.

[0103] 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 process to ensure consistency and repeatability of the test conditions.

[0104] In a possible embodiment, the step of controlling the robot servo motor based on the standard test configuration to implement a position holding mode to determine the gravity torque reference of the standard test configuration comprises:

[0105] 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;

[0106] 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;

[0107] 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;

[0108] 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.

[0109] 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 mode the motor will strictly maintain a given position command and generate necessary resistance torque through closed-loop control to keep the position constant; the zero speed closed-loop control mode is a specific way to achieve position holding, and the control target is to maintain the motor speed at zero; the static steady state refers to a system state in which the deviation between the actual position of each joint of the robot and the command position is continuously within a very small range and remains stable; and the set of gravity torque reference values 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.

[0110] The embodiment switches all joint servo motors to the position holding mode to rigidly lock the robot as a whole, then determines whether the system reaches complete static equilibrium by continuously monitoring the position deviation, and after confirming that the stable state is reached, synchronously collects the torque data of each joint through a high-speed real-time industrial bus and stores the data as standardized gravity torque references.

[0111] In a 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 determinacy and time synchronization features 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.

[0112] In a specific implementation, the robot control system switches all joint servo drivers of a six-axis robot to the position holding mode and continuously monitors the position deviation of the six joints. When it is monitored that the position deviation of all joints is less than 0.0008 radian and remains stable for 1.2 seconds, it is determined that the system enters a static steady state. At this time, the real-time torque feedback values of the six servo drivers [15.2 Nm, -8.7 Nm, 22.3 Nm, 1.5 Nm, 0.8 Nm, 0.2 Nm] are synchronously read through the EtherCAT bus, and this set of values is stored as a set of gravity torque reference values under the current standard test configuration.

[0113] In a possible implementation, 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 to make the target test joint generate a dynamic alternating torque load based on the gravity torque reference, the method further includes:

[0114] determining a selection criterion for the excitation joint based on the motion characteristics of the target test scenario;

[0115] Based on the topology of the robot, all joints directly connected to the target test joint through a connecting rod are defined as a candidate excitation joint set;

[0116] Under the standard test configuration, the coupling influence factor of each joint in the candidate excitation joint set on the target test joint is calculated based on the force Jacobian matrix of the robot;

[0117] The equivalent motion inertia of each joint in the candidate excitation joint set under the standard test configuration is calculated;

[0118] 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 and the lowest equivalent motion inertia above the preset coupling threshold is selected as the final excitation joint.

[0119] It should be noted that in the present 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 strength of the 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 the excitation. The present 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 the control energy consumption and improves the system response speed.

[0120] Alternatively, 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 the specific test requirements or test scene, seeking the optimal balance between coupling strength and motion inertia. The preset coupling threshold can be set according to the specific application requirements, such as setting it to 60% of the maximum coupling influence factor.

[0121] Further, with reference to Figure 3 , the third embodiment of the robot precision reducer performance test method provided by the present application provides a flowchart, based on the above Figure 3The embodiment shown further refines the step of "controlling the 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" in step S30, including steps A301-A306:

[0122] Step A301, based on the load characteristics of the target test scene and the dynamics model of the robot, determine the excitation parameters, 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 slight range;

[0123] 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 of the robot in the actual working environment, including load size, direction, variation 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 pattern. The waveform type of the excitation motion refers to the function form describing the variation law of the angle of the excitation joint with time, such as sine wave, triangle wave or square wave; the excitation amplitude refers to the maximum angular displacement of the excitation joint around its balance position; the excitation frequency refers to the number of complete cycles of the excitation motion completed in unit time; the preset slight range refers to the angular variation interval set to ensure that the overall configuration of the robot does not change significantly during the test, usually less than ±1 degree. By establishing an excitation parameter system matching the target test scene, it is ensured that the generated dynamic load meets the test requirements and ensures system safety.

[0124] Step A302, by superimposing a dynamic alternating angular displacement instruction defined by the excitation parameters on the static position instruction corresponding to the gravity torque reference of the excitation joint, to synthesize the total position instruction;

[0125] It should be noted that in the embodiments of the present application, the static position instruction refers to the angle instruction value that makes the excitation joint stable at the balance position in the labeled test configuration; the dynamic alternating angular displacement instruction refers to the time-varying angular instruction component determined by the excitation parameters; the total position instruction refers to the linear superposition result of the static position instruction and the dynamic alternating angular displacement instruction.

[0126] Optionally, the static position instruction of the excitation joint after gravity compensation is θ0=1.2 radian, the dynamic alternating angular displacement instruction is θ1(t)=0.01sin(10πt) radian (corresponding to ±0.57 degrees, 5Hz sine motion), and the synthesized total position instruction is θ_cmd(t)=1.2+0.01sin(10πt) radian.

[0127] Step A303, injecting the total position instruction into the servo motor of the excitation joint to drive the excitation joint to perform a slight high-frequency reciprocating motion consistent with the load characteristics;

[0128] It should be noted that in the embodiments of the present application, the generated total position instruction is sent to the servo driver through the real-time communication bus. The periodic angular change of the micro-amplitude high-frequency reciprocating motion excitation joint according to the synthesized instruction trajectory matches the periodic angular change of the target test scene load characteristics. The periodic angular change of the micro-amplitude high-frequency reciprocating motion excitation joint according to the synthesized instruction trajectory. By accurately executing the preset excitation motion mode, a stable and reliable dynamic load source is provided for testing.

[0129] Step A304, real-time monitoring of the instantaneous output torque of the target test joint and the excitation joint;

[0130] It should be noted that in the embodiments of the present application, the instantaneous output torque refers to the current output torque instantaneous value of the servo driver in real time.

[0131] Step A305, comparing the instantaneous output torque with the preset safety threshold based on the target test scene, wherein the preset safety threshold is calculated by the gravity torque reference and the dynamics model;

[0132] It should be noted that in the embodiments of the present application, the preset safety threshold based on the target test scene refers to the torque safety upper limit value set according to the safety requirements of the specific test scene. 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.

[0133] Step A306, 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 instruction.

[0134] 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, a safety mechanism is triggered immediately to stop the sending of the excitation instruction, and all joints are switched to a safety state to prevent equipment damage.

[0135] The generation of dynamic load is transformed into a parameterized, predictable and reliable operation with inherent safety fault tolerance capability. Through parameter initialization based on the dynamic model, the scientificity and optimality of the excitation motion are ensured; through instruction synthesis and injection, the accurate generation of dynamic load and the stable maintenance of the overall configuration of the robot are realized; and the real-time torque monitoring and automatic safety termination 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 the real robot.

[0136] Further, with reference to Figure 4 , the fourth embodiment of the robot precision reducer performance test method of the application provides a flowchart, which is based on the above-mentioned Figure 4 embodiment, and further refines 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, calculating the net excitation torque, and then constructing the torque-angle hysteresis curve" in step S40, including steps A401-A404:

[0137] 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;

[0138] It should be noted that in the embodiment of the 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 that can directly read the mechanical position without accumulating pulses and has 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.

[0139] 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;

[0140] It should be noted that in the embodiment of the 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 the excitation motion, which has eliminated the interference of gravity.

[0141] Step A403, filtering the net exciting torque data and the angular displacement data containing a complete exciting period from the net exciting torque time series and the angular displacement time series, taking the actual position feedback value of the exciting joint as a reference benchmark;

[0142] It should be noted that in the embodiments of the present application, the complete exciting period refers to the data segment corresponding to one complete reciprocating motion of the exciting joint (such as one complete 2π phase change of a sine wave), excluding the interference of the start and stop transient or unstable period to ensure the accuracy of performance testing.

[0143] Step A404, drawing a scatter plot in the coordinate system with the filtered angular displacement data as the X-axis and the corresponding net exciting torque data as the Y-axis, and connecting in time sequence to form the dynamic torque-rotation angle hysteresis curve of the precision reducer.

[0144] It should be noted that in the embodiments of the present application, the dynamic torque-rotation angle hysteresis curve refers to a closed curve describing the nonlinear relationship between the output torque and the input rotation angle of the precision reducer under dynamic alternating load. This curve comprehensively reflects the characteristics of the reducer such as stiffness, friction and clearance, i.e. converts time series data into a characteristic graph that can intuitively and comprehensively represent the dynamic transmission performance of the reducer.

[0145] The present embodiment ensures the time consistency of the data through multi-channel synchronous acquisition, effectively eliminating the time shift error; the real dynamic response of the reducer is highlighted by calculating the net exciting torque, which strips away the gravity interference; the effectiveness and representativeness of the analysis data are guaranteed by the period filtering mechanism, excluding the interference of the transient process; finally, the complex dynamic transmission characteristics are converted into intuitive and quantifiable graphical representation through the construction of the hysteresis curve, significantly improving the accuracy and reliability of the test results.

[0146] In one possible implementation, the step of calculating the back-lash of the precision reducer based on the torque-rotation angle hysteresis curve includes:

[0147] Positioning the interval where the net exciting torque is zero on the torque-rotation angle hysteresis curve;

[0148] Within the interval where the net exciting torque is zero, 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-rotation angle hysteresis curve;

[0149] 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.

[0150] It should be noted that in the embodiments of the present application, the uplink path refers to the trajectory part in the hysteresis curve in which the torque changes from the negative value region to the positive value region; the downlink path refers to the trajectory part in the hysteresis curve in which the torque changes from the positive value region to the negative value region; and the hysteresis refers to the transmission dead space of the precision reducer due to internal gear meshing clearance, elastic deformation and other factors, which is quantified as the angular displacement difference on the positive and negative transmission paths near zero torque. The embodiments accurately position 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 hysteresis value by calculating the absolute difference value of the two, effectively avoiding the subjective error of traditional visual reading, and realizing the objectivity and standardization of the test results.

[0151] Optionally, the zero torque interval can be defined as a continuous section in which the torque value fluctuates in the range of [-ε, +ε], where ε is a small threshold value close to zero; and 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 by calculating the average angular displacement of the two paths in the interval.

[0152] In a possible implementation, the step of calculating the torque stiffness of the precision reducer based on the torque-angle hysteresis curve comprises:

[0153] screening the sections with the highest linearity in the uplink path and the downlink path on the torque-angle hysteresis curve;

[0154] performing linear regression analysis on the linear sections of the uplink path and the downlink path screened to obtain the uplink path slope and the downlink path slope;

[0155] obtaining the torque stiffness of the precision reducer based on the arithmetic mean of the uplink path slope and the downlink path slope.

[0156] It should be noted that in the embodiments of the present application, the section with the highest linearity refers to the continuous data interval in the uplink or downlink path of the torque-angle hysteresis curve, in which the data points are most close to a straight line and best reflect 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 the 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, effectively improving the accuracy and repeatability of the stiffness calculation.

[0157] Optionally, the linearity evaluation can be achieved by calculating the determination coefficient R² between each candidate segment data point and the fitted straight line, and selecting the segment with the R² closest to 1 as the segment with the highest linearity; the linear regression analysis can adopt the least square method to perform straight line fitting.

[0158] It should be noted that the above examples are only for understanding the present application and do not constitute a limitation on the robot precision reducer performance test method of the present application. Based on this technical concept, more forms of simple transformation are within the protection scope of the present application.

[0159] The present application also provides a robot precision reducer performance test device, please refer to Figure 5 , the robot precision reducer performance test device comprises:

[0160] A test configuration planning module 10 is 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.

[0161] A gravity compensation reference module 20 is configured to control a 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.

[0162] An excitation load generation module 30 is configured to control an 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 as to generate a dynamic alternating torque load of the target test joint.

[0163] A first data processing module 40 is configured to 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 construct a torque-angle hysteresis curve.

[0164] A 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.

[0165] The robot precision reducer performance test device provided by the present application adopts the robot precision reducer performance test method in the above embodiments, and can solve the technical problem that the 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 device provided by the present application has the same beneficial effects as the robot precision reducer performance test method provided by the above embodiments, and the other technical features in the robot precision reducer performance test device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0166] The application provides a robot precision reducer performance testing device, which comprises at least one processor and a memory connected 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 the embodiment I.

[0167] Reference will be made to the following drawings to make the above objects, features and advantages of the embodiments of the application clearer. Figure 6 which shows a structural diagram of a robot precision reducer performance testing device suitable for implementing the embodiments of the application. The robot precision reducer performance testing device in the embodiments of the 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 Media Player), 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 only an example, and should not bring any limitation to the functions and use range of the embodiments of the application.

[0168] As Figure 6As shown, the robot precision reducer performance test equipment can include a processing device 1001 (for example, a central processing unit, a graphics processing unit, etc.), which 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. In the random access memory 1004, various programs and data required for the operation of the robot precision reducer performance test equipment are also stored. 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: an input device 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; a 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 wired 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.

[0169] 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 a 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.

[0170] 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 the 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 repeated here.

[0171] 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 above embodiments, specific features, structures, materials or characteristics can be combined in any appropriate manner in any one or more embodiments or examples.

[0172] 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.

[0173] The application provides a computer readable storage medium having computer readable program instructions (i.e. computer programs) stored thereon, the computer readable program instructions being used to perform the robot precision reducer performance testing method in the above embodiments.

[0174] 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 appropriate 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 appropriate medium, including but not limited to an electric wire, an optical cable, an RF (Radio Frequency), etc., or any appropriate combination thereof.

[0175] The above computer readable storage medium can be contained in the robot precision reducer performance testing device; or can exist separately and not be assembled into the robot precision reducer performance testing device.

[0176] 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.

[0177] 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).

[0178] 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 combinations of hardware and software.

[0179] 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 name of the module does not constitute a limitation on the unit itself.

[0180] The readable storage medium provided by the present application is a computer readable storage medium, which stores computer readable program instructions (i.e. computer programs) for executing the above-mentioned robot precision reducer performance testing method, 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.

[0181] 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.

[0182] 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.

[0183] 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 where the precision reducer is located, and acquiring a standard test configuration of the target test joint based on a dynamics model of the robot; the step of acquiring the standard test configuration of the target test joint based on the dynamics model of the robot comprises: acquiring a target test scene, determining a key working pose of the robot based on a typical motion trajectory of the target test scene, calling the dynamics model of the robot, calculating a force Jacobian matrix under the key working pose based on the dynamics model, defining or generating a set of candidate test configurations in a target working area of the robot based on load characteristics of the target test scene, calculating a torque amplification coefficient of the target test joint under a current configuration through the force Jacobian matrix for each candidate test configuration, and comparing the torque amplification coefficients corresponding to each candidate test configuration to select a candidate test configuration with the largest torque amplification coefficient as the standard test configuration; controlling robot servo motors to implement a position holding mode based on the standard test configuration to determine a gravity torque reference of the standard test configuration; determining a selection criterion of an excitation joint based on motion characteristics of the target test scene, defining all joints directly connected to the target test joint through connecting rods as a candidate excitation joint set based on a 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, and screening a candidate excitation joint with the coupling influence factor higher than a preset coupling threshold and the equivalent motion inertia lowest as a final excitation joint based on the coupling influence factor and the equivalent motion inertia in combination with the selection criterion of the excitation joint; 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 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 angle hysteresis curve; calculating the backlash and torque stiffness of the precision reducer based on the torque-rotation angle hysteresis curve.

2. The robotic precision reducer performance testing method of claim 1, wherein, the step of controlling robot servo motors to implement a position holding mode based on the standard test configuration to determine 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 torque output by the servo motor of each joint, 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 stationary state, the real-time output torque feedback value of each joint servo motor is synchronously read and recorded 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.

3. The robotic precision reducer performance testing method of claim 1, wherein, 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 includes: Based on the load characteristics of the target test scenario 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 predetermined 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; Real-time monitoring of the instantaneous output torque of the target test joint and the excitation joint; Compare the instantaneous output torque with a preset safety threshold based on the target test scenario, wherein the preset safety threshold is calculated based on 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.

4. The robotic precision reducer performance testing method of claim 3, 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 hysteresis curve includes: 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 of the high-resolution absolute encoder feedback of the target test joint, and the actual position feedback value of the excitation joint are synchronously collected; The measured output torque time series collected synchronously is subtracted point by point 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 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 hysteresis curve of the precision reducer.

5. The robotic precision reducer performance testing method of claim 4, wherein, The step of calculating the back-lash of the precision reducer based on the torque-rotation hysteresis curve includes: Locating the interval where the net excitation torque is zero on the torque-rotation hysteresis curve; Within the interval where the net excitation torque is zero, the angular displacement values corresponding to the torque-rotation 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 are calculated. The absolute difference between the angle displacement values of the uplink path and the downlink path is used to obtain the back-lash of the precision reducer.

6. The robotic precision reducer performance testing method of claim 5, 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 in 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 used to obtain the torque stiffness of the precision reducer.

7. A robot precision reducer performance testing device, characterized by, The robot precision reducer performance testing device comprises: A test configuration planning module is 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. The test configuration planning module is further configured to obtain a target test scenario, determine a key working pose of the robot based on a typical motion trajectory of the target test scenario, call the dynamics model of the robot, calculate a force Jacobian matrix of the robot at the key working pose based on the dynamics model, define or generate a set of candidate test configurations in the target working area of the robot based on the load characteristics of the target test scenario, calculate a torque amplification coefficient of the target test joint in the current configuration through the force Jacobian matrix for each candidate test configuration, compare the torque amplification coefficients corresponding to each candidate test configuration, and select the candidate test configuration with the largest torque amplification coefficient as the standard test configuration. A gravity compensation reference module is 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. An excitation load generation module is configured to determine a selection criterion of an excitation joint based on the motion characteristics of the target test scenario, define 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, calculate 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 in the standard test configuration, calculate the equivalent motion inertia of each joint in the candidate excitation joint set in the standard test configuration, and screen a candidate excitation joint with a coupling influence factor higher than a preset coupling threshold and the lowest equivalent motion inertia as a final excitation joint based on the coupling influence factor and the equivalent motion inertia in combination with the selection criterion of the excitation joint. The excitation load generation module is further configured to control 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, so as to generate a dynamic alternating torque load on the target test joint. A first data processing module is configured to 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 construct a torque-angle hysteresis curve. A second data processing module is configured to calculate the back-lash and torque stiffness of the precision reducer based on the torque-angle hysteresis curve.

8. 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 test method according to any one of claims 1 to 6.

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