Torque control method and device for planetary reduction device of robot

Abstract

The present application relates to the technical field of planetary gear reduction device, especially to a torque control method and device of planetary reduction device for robot, the method comprises: collecting equipment state parameters; constructing temperature-stiffness attenuation model according to the collected equipment shell temperature to determine the stiffness factor; extracting angle characteristics, determining the compensation factor according to the angle characteristics and the stiffness factor, and updating the compensation factor according to the equipment vibration acceleration in the control period; determining the load state according to the equipment current in the control period, and determining the torque correction factor based on the load state; controlling the torque of the planetary reduction device according to the compensation factor and the torque correction factor; judging the equipment health state according to the angle characteristics, the load state of each control period in the management period and the lubricating oil temperature in the management period, and adjusting the torque control process of the next management period. The present application effectively improves the torque control efficiency of the planetary reduction device.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of planetary gear reduction device, and in particular to a torque control method and device of a planetary reduction device for robots. BACKGROUND

[0002] As the core transmission component of the industrial robot joint, the stability of the output torque of the planetary reduction device directly determines the motion accuracy and system life. The traditional torque control method often faces severe challenges: on the one hand, the stiffness characteristics of the gears and bearings inside the reducer significantly attenuate as the operating temperature rises, resulting in a decrease in transmission stiffness and an increase in backlash; on the other hand, the frequent start-stop and sudden load changes in robot operation cause impact torque, which can easily cause increased vibration and even structural damage.

[0003] Existing solutions rely on fixed parameter models or simple current feedback, which are difficult to dynamically adapt to the nonlinear changes in stiffness under variable temperature conditions, have a lag in response to sudden impacts, lack vibration suppression mechanisms, and lack closed-loop monitoring and protection strategies for the long-term health of the equipment. Especially in harsh scenarios of high temperature and high load, the above defects can easily cause control inaccuracies, precision degradation, and accelerated abnormal wear, and an intelligent torque control method that integrates multi-state sensing, adaptive compensation, and health management is urgently needed. SUMMARY

[0004] The purpose of the present application is to provide a torque control method and device of a planetary reduction device for robots to solve at least one of the problems in the prior art.

[0005] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0006] A torque control method for a planetary reduction device for robots, comprising:

[0007] Collecting device state parameters;

[0008] Constructing a temperature-stiffness attenuation model according to the collected device shell temperature to determine a stiffness factor;

[0009] Extracting an angle feature, determining a compensation factor according to the angle feature and the stiffness factor, and updating the compensation factor according to the device vibration acceleration in the control period;

[0010] Determining the load state according to the device current in the control period, and determining a torque correction factor based on the load state;

[0011] Controlling the torque of the planetary reduction device according to the compensation factor and the torque correction factor;

[0012] According to the angle feature, load state and oil temperature of the equipment in the control period, the health state of the equipment is judged, and the torque control process of the next management period is adjusted.

[0013] Optionally, a temperature-rigidity attenuation model is constructed according to the collected equipment shell temperature T, nominal rigidity K0 and rigidity attenuation coefficient α, and the rigidity factor Kt is determined, and the expression of the rigidity factor is: Kt=K0×exp[-α×(T-T0)]; wherein T0 is the reference temperature.

[0014] Optionally, the difference between the input shaft angle and the output shaft angle of the current control period is denoted as θ1, the difference between the input shaft angle and the output shaft angle of the previous control period adjacent to the current control period is denoted as θ2, and θ1-θ2 is taken as the angle feature of the current control period, and a compensation factor is constructed, and the expression of the compensation factor is:

[0015] Φ=Kt×θ1+β×(θ1-θ2) / Tk;

[0016] In the formula, φ is the compensation factor, β is the damping coefficient, and Tk is the time length of the control period.

[0017] Optionally, the vibration acceleration a1 in the control period is compared with the acceleration threshold a0, when a1 is greater than a0, it is determined that the vibration state in the current control period is abnormal, and the damping coefficient is updated to β1 to update the compensation factor, otherwise, it is determined that the vibration state in the current control period is normal, and the damping coefficient is not updated.

[0018] The expression of β1 is:

[0019] β1=β×(1+η×a1 / a0); η is a correction factor.

[0020] Optionally, the difference between the equipment current d1 of the current control period and the equipment current d2 of the adjacent previous control period is calculated and denoted as dm, and the equipment current change rate B is calculated, B=|dm / Tk|;

[0021] The equipment current change rate B is compared with the current change rate threshold b0, when B is less than or equal to b0, it is determined that the load state is normal, otherwise, it is determined that the load state is impact state.

[0022] Optionally, when the load state is impact state, the torque correction factor P is determined, and the expression is:

[0023] P=sgn(θ1-θ2)×min(Pmax,h×|d|×e -t / tc );

[0024] In the formula, h is a current-torque conversion coefficient, d is a real-time device current collected when the injected torque correction factor is collected, t is a time length of the injected torque correction factor, tc is a time constant, Pmax is a maximum allowable compensation torque, and e is a natural logarithm.

[0025] Optionally, when the load state is a normal state, the torque of the device is controlled as L1, and L1=L0+φ is set.

[0026] When the load state is an impact state, the torque of the device is controlled as L2, and L2=L0+γ1×φ+P is set.

[0027] Wherein, L0 is a basic torque, and γ1 is a correction factor.

[0028] Optionally, the number of control periods in which the absolute value of the angle feature is greater than an angle threshold value in a management period is m1, the number of control periods in which the load state is an impact state in the management period is m2, and the total number of control periods in the management period is M.

[0029] The average value of the lubricating oil temperature in the management period is calculated as Tj, and a temperature factor is constructed: when Tj is less than or equal to a temperature threshold value Ty, the temperature factor is set to 0, otherwise, the temperature factor is set to ln[(Tj-Ty) / (Ty+Tj)+1].

[0030] A health index is constructed based on m1, m2, M and the temperature factor, and the expression of the health index is:

[0031] G=(y1×m1+y2×m2) / M+tt×temperature factor.

[0032] In the formula, y1 is an angle weight, y2 is a load weight, y1+y2=1, and tt is a temperature weight.

[0033] When G is less than or equal to a health threshold value g1, it is determined that the health state of the device in the current management period is qualified, otherwise, it is determined that the health state of the device in the current management period is unqualified.

[0034] Optionally, when the health state of the device is unqualified, the maximum allowable compensation torque of the next management period is adjusted as u×Pmax, and u is an adjustment coefficient.

[0035] According to another aspect of the present application, a torque control device of a planetary reduction device for a robot is provided, comprising:

[0036] A collection unit is configured to collect device state parameters.

[0037] A decay analysis unit is configured to construct a temperature-stiffness decay model according to the collected device shell temperature to determine a stiffness factor.

[0038] A compensation factor determination unit is configured to extract an angle feature, determine a compensation factor according to the angle feature and a stiffness factor, and update the compensation factor according to the device vibration acceleration in a control period;

[0039] A torque correction determination unit is configured to determine a load state according to the device current in a control period, and determine a torque correction factor based on the load state;

[0040] A control unit is configured to control the torque of the planetary reduction device according to the compensation factor and the torque correction factor;

[0041] A management unit is configured to determine the device health state according to the angle feature and the load state in each control period in a management period, and the oil temperature of the lubricating oil in the management period, and adjust the torque control process in the next management period.

[0042] The present application has the following advantages: through multi-dimensional real-time state perception and intelligent algorithm fusion, high-precision and high-robustness torque output is realized. The core value lies in: dynamic compensation of variable temperature stiffness attenuation, real-time correction of stiffness factor by using temperature-stiffness model, significant improvement of torque transmission accuracy in temperature drift environment; intelligent suppression of vibration and impact, adaptive compensation factor based on angle feature and vibration feedback effectively absorbs elastic deformation and suppresses abnormal oscillation, combined with impact state identified by current change rate and transient torque injection with attenuation characteristics, greatly enhances the anti-interference ability and running stability of the system; health state driven preventive protection, through long-period running feature evaluation of device health degree, and dynamically adjusting the upper limit of control parameters according to the health degree, actively limiting the stress level when the state deteriorates, prolonging the service life of key components. The overall scheme realizes the whole cycle optimization from real-time response to long-term maintenance, and guarantees the reliable, accurate and durable operation of the robot in complex working conditions. BRIEF DESCRIPTION OF DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0044] Figure 1 The flowchart of the torque control method of the planetary reduction device for the robot in the present embodiment.

[0045] Figure 2 The flowchart of the determination method of the compensation factor in the present embodiment.

[0046] Figure 3 The flowchart of the device health state analysis method in the present embodiment.

[0047] Figure 4A schematic structural view of a torque control device of a planetary speed reduction device for a robot according to the embodiment. DETAILED DESCRIPTION

[0048] In order to more clearly illustrate the application, the application will be further described below with reference to the preferred embodiments and the accompanying drawings. Like reference numerals in the drawings denote like elements throughout. It should be understood by those skilled in the art that the specific description below is illustrative rather than restrictive and should not be construed as limiting the scope of the application.

[0049] It should be noted that the terms "first", "second", and the like in the description and claims of the application and the above drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the application described herein can be implemented. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily limit to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to the process, method, product or device.

[0050] Specifically, the present scheme is applied to an industrial robot joint driving system, solves the torque control misalignment problem caused by stiffness attenuation and vibration anomaly of the planetary speed reduction device under variable temperature conditions and load impact, and realizes high-precision and high-robustness torque stable output through temperature-stiffness dynamic compensation, vibration sensing damping adjustment and load state adaptive correction.

[0051] Referring to Figure 1 As shown in the figure, a flowchart of a torque control method of a planetary speed reduction device for a robot according to the embodiment includes:

[0052] Step S101, collecting device state parameters, including device current, device shell temperature, device lubricating oil temperature, device input shaft angle, device output shaft angle and device vibration acceleration, the device being a planetary speed reduction device.

[0053] For example, in the present embodiment, the device current can be collected by a Hall sensor built-in servo driver, a MEMS accelerometer can be installed at the output end bearing seat of the planetary reducer to collect vibration acceleration, a temperature sensor can be used to collect real-time device lubricating oil temperature and device shell temperature, and double absolute value encoders can be used to collect device input shaft angle and device output shaft angle. In the present embodiment, the above settings are not specifically limited, and those skilled in the art can freely set them according to the needs.

[0054] Please continue to refer to Figure 1 As shown in the figure, the torque control method of the planetary speed reduction device for the robot further includes:

[0055] In step S102, a temperature-stiffness attenuation model is constructed according to the collected device shell temperature, so as to determine the stiffness factor.

[0056] Specifically, the temperature-stiffness attenuation model is constructed according to the collected device shell temperature T, the nominal stiffness K0 and the stiffness attenuation coefficient a, and the stiffness factor is determined as Kt, and the expression of the stiffness factor is: Kt=K0×exp[-a×(T-T0)].

[0057] Wherein, T0 is the reference temperature.

[0058] For example, in the present embodiment, the nominal stiffness is the nominal stiffness at the reference temperature, which can be obtained by offline calibration, the reference temperature can be set to 25℃, and the stiffness attenuation coefficient can be set to 0.0015 / ℃, and the above settings are not specifically limited in the present embodiment, and can be freely set by the person skilled in the art according to the requirements.

[0059] Specifically, the law of the stiffness of the planetary reduction device changing with temperature is quantified, the temperature influence is converted into a calculable stiffness attenuation factor, an accurate stiffness reference is provided for subsequent torque compensation based on actual working conditions, and the error of the fixed stiffness model in the variable temperature environment is overcome.

[0060] Please continue to refer to Figure 1 As shown in the figure, the torque control method of the planetary reduction device for robots further comprises:

[0061] In step S103, the angle feature is extracted, the compensation factor is determined according to the angle feature and the stiffness factor, and the compensation factor is updated according to the device vibration acceleration in the control period.

[0062] Please refer to Figure 2 As shown in the figure, the determination method of the compensation factor comprises:

[0063] In step S201, the angle feature is extracted according to the input shaft angle and the output shaft angle in the control period, and the compensation factor is determined according to the angle feature and the stiffness factor.

[0064] Specifically, the difference between the input shaft angle and the output shaft angle in the current control period is denoted as θ1, the difference between the input shaft angle and the output shaft angle in the last control period adjacent to the current control period is denoted as θ2, θ1-θ2 is taken as the angle feature of the current control period, and the compensation factor is constructed, and the expression of the compensation factor is:

[0065] Φ=Kt×θ1+β×(θ1-θ2) / Tk;

[0066] In the formula, φ is the compensation factor, β is the damping coefficient, and Tk is the length of the control period.

[0067] Exemplarily, in the embodiment, the control period can be set as 0.5 ms, and the damping coefficient can be set as 0.8 N·m·s / rad. The above settings are not specifically limited in the embodiment, and can be set freely by those skilled in the art according to requirements.

[0068] Specifically, the real-time torsional deformation of the reducer and the change trend thereof are converted into a torque compensation amount, the compensation amount fuses the actual stiffness information at the current temperature, and the torque compensation amount can more accurately offset the torque transmission error caused by the flexibility of the reducer.

[0069] Please continue to refer to Figure 2 As shown, the determination method of the compensation factor further includes:

[0070] In step S202, the damping coefficient is updated according to the equipment vibration acceleration in the control period, so as to update the compensation factor.

[0071] Specifically, the vibration acceleration a1 in the control period is compared with the acceleration threshold a0. When a1 is greater than a0, it is determined that the vibration state in the current control period is abnormal, and the damping coefficient is updated to β1 to update the compensation factor. Otherwise, it is determined that the vibration state in the current control period is normal, and the damping coefficient is not updated.

[0072] The expression of β1 is:

[0073] β1=β×(1+η×a1 / a0); η is a correction factor.

[0074] Specifically, if there is no control period before the current control period, the angle feature of the current control period is not determined, and the angle feature is set to 0.

[0075] Exemplarily, in the embodiment, the acceleration threshold can be set as 15 m / s 2 The correction factor can be set as 0.2. The above settings are not specifically limited in the embodiment, and can be set freely by those skilled in the art according to requirements.

[0076] Specifically, by monitoring the vibration intensity, when abnormal vibration is detected, the damping term coefficient in the compensation factor is adaptively increased to enhance the oscillation suppression ability of the system, effectively improve the stability and anti-interference of the torque control, and prevent the system from being unstable due to over-compensation or resonance.

[0077] Please continue to refer to Figure 1 As shown, the torque control method of the planetary reducer device for robots further includes:

[0078] In step S104, the load state is determined according to the equipment current in the control period, and the torque correction factor is determined based on the load state.

[0079] Specifically, a difference between the device current d1 of the current control period and the device current d2 of the adjacent previous control period is calculated as dm, and a device current change rate B is calculated, B = |dm / Tk|; Tk represents a control period of the device current.

[0080] The device current change rate B is compared with a current change rate threshold b0, and when B is less than or equal to b0, it is determined that the load state is a normal state, otherwise, it is determined that the load state is an impact state.

[0081] When the load state is the impact state, a torque correction factor P is determined, and the expression is:

[0082] P = sgn (θ1-θ2) x min (Pmax, h x |d| x e -t / tc ).

[0083] In the formula, h is a current-torque conversion coefficient, d is a real-time device current collected when the torque correction factor is injected, t is a duration of the torque correction factor, tc is a time constant, Pmax is a maximum allowable compensation torque, and e is a natural logarithm.

[0084] Specifically, in the embodiment, the duration of the torque correction factor is a continuous duration of the torque correction factor, and is reset at the end of the torque correction factor.

[0085] Specifically, if there is no control period before the current control period, it is determined that the load state of the current control period is a normal state.

[0086] For example, in the embodiment, the current-torque conversion coefficient can be obtained through a motor parameter manual, the time constant can be set to 0.02 seconds, the maximum allowable compensation torque can be set to a rated torque x 0.2, and the current change threshold can be set to 500 A / s; the above settings are not specifically limited in the embodiment, and can be freely set by a person skilled in the art according to requirements.

[0087] Specifically, by analyzing the motor current change rate, it is intelligently identified whether the load is in a stable state or suffers from a sudden impact. In the impact state, an additional torque correction factor with a time decay characteristic is generated, which can quickly respond to current mutation, provide instantaneous additional torque to resist the impact, and avoid overshoot and continuous oscillation through a decay mechanism, thereby significantly improving the anti-impact ability of the system to respond to sudden loads.

[0088] Please continue to refer to Figure 1 As shown in the figure, the torque control method of the robot planetary reduction device further includes:

[0089] In step S105, the torque of the planetary reduction device is controlled according to the compensation factor and the torque correction factor.

[0090] Specifically, when the load state is a normal state, the torque of the device is controlled as L1, and L1 is set as L0 + φ;

[0091] When the load state is an impact state, the torque of the device is controlled as L2, and L2 is set as L0 + γ1 × φ + P.

[0092] Wherein, L0 is a basic torque, and γ1 is a correction factor.

[0093] Specifically, in the embodiment, when the torque of the device is greater than the torque threshold, the torque of the planetary reduction device is controlled as the torque threshold, which can be set as 1.2 times of the rated torque. The basic torque and the torque threshold can be collected by the robot controller, and the correction factor can be set as 0.3. In the embodiment, the above setting is not specifically limited, and a person skilled in the art can freely set according to the needs.

[0094] Specifically, the compensation factor and the torque correction factor generated in the foregoing steps are comprehensively applied to intelligently superimpose on the basic torque to form a final control torque instruction adapted to different working conditions. This step realizes fine and adaptive adjustment of torque output, ensures high-precision torque output and system stability under various operating conditions, and is provided with a safety upper limit protection mechanism.

[0095] Please continue to refer to Figure 1 As shown in the figure, the torque control method of the robot planetary reduction device further includes:

[0096] Step S106, judging the device health state according to the angle characteristics of each control period, the load state and the lubricating oil temperature in the management period, and adjusting the torque control process of the next management period.

[0097] Please refer to Figure 3 As shown in the figure, the device health state analysis method includes:

[0098] Step S301, judging the device health state according to the angle characteristics of each control period, the load state and the lubricating oil temperature in the management period.

[0099] Specifically, the number of control periods in which the absolute value of the angle characteristic is greater than the angle threshold in the management period is counted as m1, the number of control periods in which the load state is an impact state in the management period is counted as m2, and the total number of control periods in the management period is counted as M.

[0100] The average value of the lubricating oil temperature in the management period is calculated as Tj, and the temperature factor is constructed: when Tj is less than or equal to the temperature threshold Ty, the temperature factor is set as 0, otherwise, the temperature factor is set as ln[(Tj-Ty) / (Ty+Tj)+1];

[0101] The health index is constructed based on m1, m2, M and the temperature factor, and the expression of the health index is:

[0102] G = (y1xm1 + y2xm2) / M + ttxtemperature factor;

[0103] In the formula, y1 is an angle weight, y2 is a load weight, y1 + y2 = 1, and tt is a temperature weight.

[0104] When G is less than or equal to a health threshold g1, it is determined that the health status of the current management period device is qualified, otherwise, it is determined that the health status of the current management period device is unqualified.

[0105] For example, in the embodiment, the angle weight can be set to 0.4, the load weight can be set to 0.6, the temperature weight can be set to 0.1, and the health threshold can be set to 0.18; the above settings are not specifically limited in the embodiment, and a person skilled in the art can freely set them according to requirements.

[0106] For example, in the embodiment, the management period can be set to 1h, and the above setting is not specifically limited in the embodiment, and a person skilled in the art can freely set it according to requirements.

[0107] Specifically, by counting the frequency of occurrence of key abnormal events and combining the oil temperature factor reflecting the lubrication and wear condition, a comprehensive health index is constructed to objectively and quantitatively evaluate the current health condition and potential risk of the reducer, thereby providing a basis for maintenance decision.

[0108] Please continue to refer to Figure 3 As shown in the figure, the device health status analysis method further includes:

[0109] In step S302, the torque control process of the next management period is adjusted according to the device health status.

[0110] Specifically, when the device health status is unqualified, the maximum allowed compensation torque of the next management period is adjusted to uXPmax, and u is an adjustment coefficient.

[0111] For example, in the embodiment, the adjustment coefficient can be set to 0.8, and the above setting is not specifically limited in the embodiment, and a person skilled in the art can freely set it according to requirements.

[0112] Specifically, when it is detected that the health status is unqualified, the upper limit of the maximum compensation torque allowed in the next period is actively reduced, which aims to limit the stress level of the device when the device status is poor, reduce the risk of further damage, prolong the service life of the device, and reflect the intelligent and safety design of the control system.

[0113] Please refer to Figure 4As shown, the torque control device of the robot planetary reducer comprises:

[0114] The acquisition unit is configured to acquire the device state parameters.

[0115] The attenuation analysis unit is configured to construct a temperature-stiffness attenuation model according to the acquired device shell temperature to determine the stiffness factor.

[0116] The compensation factor determination unit is configured to extract the angle feature, determine the compensation factor according to the angle feature and the stiffness factor, and update the compensation factor according to the device vibration acceleration in the control period.

[0117] The torque correction determination unit is configured to determine the load state according to the device current in the control period, and determine the torque correction factor based on the load state.

[0118] The control unit is configured to control the torque of the planetary reducer according to the compensation factor and the torque correction factor.

[0119] The management unit is configured to determine the device health state according to the angle feature and the load state in each control period in the management period and the lubricating oil temperature in the management period, and adjust the torque control process in the next management period.

[0120] The torque control device of the robot planetary reducer provided by the embodiments of the present application can execute the torque control method of the robot planetary reducer provided by any embodiment of the present application, and has the corresponding function modules and beneficial effects of the execution method.

[0121] The present application also provides a computer readable storage medium, which is a tangible physical storage medium that can store the above computer program and various types of data used in the program; the physical storage medium includes but is not limited to random access memory, read-only memory, optical disc, hard disk, etc. existing physical storage medium or combination of media.

[0122] As will be appreciated by one of ordinary skill in the art, all or some of the steps, systems, and techniques disclosed herein can be embodied in software, firmware, hardware, or any suitable combination thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or as hardware, or as an integrated circuit, such as an application- specific integrated circuit. Such software can be distributed on computer readable media, which can comprise computer storage media (or non-transitory media), and communication media (or transitory media). As is well known to those of ordinary skill in the art, the term computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media include, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by a computer. Further, as is well known to those of ordinary skill in the art, communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media.

[0123] Obviously, the above-described embodiments of the present application are only examples for clearly illustrating the present application, and are not intended to limit the implementation of the present application. Based on the above description, other different forms of changes or variations can be made by those of ordinary skill in the art, and it is impossible to enumerate all the embodiments here. Any obvious changes or variations derived from the technical solutions of the present application are still within the protection scope of the present application.

Claims

1. A torque control method for a planetary reduction gear for a robot, characterized in that, include: Collect device status parameters; A temperature-stiffness decay model is constructed based on the collected equipment housing temperature to determine the stiffness factor; Extract angular features, determine compensation factors based on angular features and stiffness factors, and update compensation factors based on equipment vibration acceleration within the control cycle. The load status is determined based on the equipment current during the control cycle, and the torque correction factor is determined based on the load status. The torque of the planetary reduction gear is controlled based on the compensation factor and torque correction factor. The health status of the equipment is determined based on the angle characteristics, load status, and lubricating oil temperature of each control cycle within the management cycle, and the torque control process for the next management cycle is adjusted accordingly. A temperature-stiffness attenuation model is constructed based on the collected equipment housing temperature T, nominal stiffness K0, and stiffness attenuation coefficient α, and the stiffness factor is determined to be Kt. The expression for the stiffness factor is: Kt=K0×exp[-α×(T-T0)]; where T0 is the reference temperature. The difference between the input axis angle and the output axis angle in the current control cycle is denoted as θ1, and the difference between the input axis angle and the output axis angle in the previous control cycle adjacent to the current control cycle is denoted as θ2. θ1-θ2 is used as the angle characteristic of the current control cycle, and a compensation factor is constructed. The expression for the compensation factor is: Φ=Kt×θ1+β×(θ1-θ2) / Tk; In the formula, φ is the compensation factor, β is the damping coefficient, and Tk is the duration of the control cycle; The vibration acceleration a1 within the control cycle is compared with the acceleration threshold a0. If a1 is greater than a0, the vibration state within the current control cycle is determined to be abnormal, and the damping coefficient is updated to β1 to update the compensation factor. Otherwise, the vibration state within the current control cycle is determined to be normal, and the damping coefficient is not updated. The expression for β1 is: β1 = β × (1 + η × a1 / a0); η is the correction factor.

2. The torque control method for a planetary reduction gear for a robot according to claim 1, characterized in that, Calculate the difference between the equipment current d1 in the current control cycle and the equipment current d2 in the adjacent previous control cycle, denoted as dm, and calculate the equipment current change rate B, B=|dm / Tk|; The current change rate B of the equipment is compared with the current change rate threshold b0. When B is less than or equal to b0, the load state is determined to be normal; otherwise, the load state is determined to be impact state.

3. The torque control method for a planetary reducer for robots according to claim 2, characterized in that, When the load condition is an impact condition, the torque correction factor is determined to be P, and the expression is: P=sgn(θ1-θ2)×min(Pmax,h×|d|×e -t / tc ); In the formula, h is the current-torque conversion coefficient, d is the real-time equipment current collected when injecting the torque correction factor, t is the duration of injecting the torque correction factor, tc is the time constant, Pmax is the maximum allowable compensation torque, and e is the natural logarithm.

4. The torque control method for a planetary reducer for robots according to claim 3, characterized in that, When the load is under normal conditions, the torque of the equipment is controlled to L1, and L1 = L0 + φ is set. When the load condition is an impact condition, the torque of the equipment is controlled to L2, and L2 is set to L0 + γ1 × φ + P; Where L0 is the basic torque and γ1 is the correction factor.

5. The torque control method for a planetary reducer for a robot according to claim 4, characterized in that, The number of control cycles in which the absolute value of the angle characteristic is greater than the angle threshold within the statistical management cycle is m1, the number of control cycles in which the load state is in the impact state within the statistical management cycle is m2, and the total number of control cycles within the statistical management cycle is M. The average lubricating oil temperature during the management cycle is calculated as Tj, and a temperature factor is constructed: when Tj is less than or equal to the temperature threshold Ty, the temperature factor is set to 0; otherwise, the temperature factor is set to ln[(Tj-Ty) / (Ty+Tj)+1]. A health index is constructed based on m1, m2, M, and a temperature factor. The expression for the health index is: G = (y1 × m1 + y2 × m2) / M + tt × temperature factor; In the formula, y1 is the angle weight, y2 is the load weight, y1+y2=1, and tt is the temperature weight; When G is less than or equal to the health threshold g1, the health status of the equipment in the current management cycle is determined to be qualified; otherwise, the health status of the equipment in the current management cycle is determined to be unqualified.

6. The torque control method for a planetary reducer for a robot according to claim 5, characterized in that, When the equipment health status is unqualified, the maximum allowable compensation torque for the next management cycle will be adjusted to u×Pmax, where u is the adjustment coefficient.

7. A torque control device for a planetary reducer for a robot, applied to the torque control method for a planetary reducer for a robot as described in any one of claims 1-6, characterized in that, include: The data acquisition unit is used to collect device status parameters; The attenuation analysis unit is used to construct a temperature-stiffness attenuation model based on the collected equipment housing temperature in order to determine the stiffness factor. The compensation factor determination unit is used to extract angle features, determine the compensation factor based on the angle features and stiffness factor, and update the compensation factor based on the equipment vibration acceleration within the control cycle. The torque correction determination unit is used to determine the load state based on the equipment current during the control cycle, and to determine the torque correction factor based on the load state. The control unit is used to control the torque of the planetary reduction gear according to the compensation factor and the torque correction factor; The management unit is used to determine the health status of the equipment based on the angle characteristics of each control cycle, the load status, and the lubricating oil temperature during the management cycle, and to adjust the torque control process for the next management cycle.

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