Harmonic reducer, method for determining life of harmonic reducer, and robot

Abstract

The application discloses a harmonic reducer and a life judging method and robot thereof, and solves the problem that the real and effective life of the reducer cannot be early warning detected in the prior art, so that the reducer is invalid, safety accidents and great economic losses are caused. The harmonic reducer comprises a rigid gear, a flexible gear, a wave generator and an early warning device, the flexible gear is sleeved on the outer periphery of the wave generator, the flexible gear is engaged with the rigid gear, and one of the flexible gear and the rigid gear constitutes a fixed component and the other constitutes an output component. The harmonic reducer and the life judging method and robot thereof can acquire the angle data signal of the harmonic reducer, analyze the transmission error characteristic frequency according to the angle data signal to acquire the amplitude of the double frequency, and compare the amplitude of the double frequency with a preset value. When the amplitude of the double frequency exceeds the preset value (that is, the performance of the harmonic reducer is distorted, and the service life of the whole machine is about to be invalid), the early warning device can perform life invalidation early warning, so that safety accidents and great economic losses caused by the invalidation of the reducer are avoided, and the working reliability of the harmonic reducer is ensured.

Description

Technical Field

[0001] This invention relates to the field of deceleration structure technology, and more specifically, to a harmonic reducer and its lifespan determination method, and a robot. Background Technology

[0002] Harmonic reducers are precision transmission devices widely used in the joint modules of industrial robots. These devices are developed based on the principle of wave deformation. A harmonic reducer typically consists of three main components: a flexible wheel, a rigid wheel, and a wave generator. The wave generator comprises a flexible bearing and a cam. During operation, the inner ring of the flexible bearing undergoes forced deformation under the action of the cam, without periodic deformation. The outer ring undergoes elastic deformation under the pressure of the rolling balls, and under external load, it undergoes periodic deformation as the wave generator rotates. Under the action of the wave generator, the elastic component, the flexible wheel, undergoes periodic elastic deformation. This deformation causes the flexible wheel teeth and the rigid wheel teeth to mesh, thereby achieving the transmission of motion and torque. In harmonic drives, the meshing of rigid gear teeth and flexible gear teeth achieves the function of reducing speed and increasing torque. The internal components of harmonic reducers are subjected to complex and variable forces, making them prone to failure. For example, while the flexible gear is deformed, it is constrained by multiple boundaries, and the cylinder wall is repeatedly deformed and bent under the support of the cam, bearing both bending moment and torque. Failure modes include tearing of the flexible gear teeth, breakage of the flexible bearing, and distortion of various performance indicators. Any failure mode poses a safety hazard. For example, if the internal reducer of industrial robots, humanoid robots, industrial machine tools, and new energy electric vehicles suddenly fails, it may cause motion control errors or even violent collisions, damage to other related systems, and safety accidents. This not only brings great trouble to maintenance or safety assurance but may also bring serious economic burdens.

[0003] Regarding the life warning monitoring of harmonic drives, researchers in this field have proposed different life warning monitoring schemes. Existing technology proposes a method for extracting degradation indicators and predicting life of reducers. By extracting and analyzing the current and vibration signals of the reducer, a degradation indicator curve is obtained for predicting the life of the harmonic reducer. However, due to the harsh working environment and complex and variable operating conditions of the reducer, and because this scheme monitors under the initial state, it cannot reflect the status of various indicators of the reducer in real time and thus cannot achieve a truly effective life warning monitoring effect. Summary of the Invention

[0004] This invention discloses a harmonic reducer that uses an early warning device to acquire angle data signals of the harmonic reducer to monitor its service life in real time and improve reliability, as well as a method for judging its service life and a robot. It solves the problem in the prior art that the reducer cannot be detected and warned of its true and effective service life, which leads to reducer failure, safety accidents and major economic losses.

[0005] This invention discloses a harmonic reducer, including a rigid wheel, a flexible wheel, a wave generator, and an early warning device. The flexible wheel is sleeved on the outer periphery of the wave generator and meshes with the rigid wheel. One of the flexible wheel and the rigid wheel constitutes a fixed component, and the other constitutes an output component. The early warning device is disposed on the fixed component and is capable of acquiring the angle data signal of the harmonic reducer and performing a life failure early warning based on the angle data signal.

[0006] The early warning device includes a first angle detection mechanism, a second angle detection mechanism, and a data analysis mechanism. The first angle detection mechanism can obtain a first relative rotation angle θ1 between the wave generator and the fixed component. The second angle detection mechanism can obtain a second relative rotation angle θ2 between the fixed component and the output component. The data analysis mechanism can obtain the first relative rotation angle θ1 and the second relative rotation angle θ2 and derive the angle data signal.

[0007] The first angle detection mechanism includes a first rotating part and a first photoelectric part. The first rotating part is disposed on the wave generator and can rotate with the wave generator. The first photoelectric part is disposed on the fixed component and can rotate relative to the first relative rotation angle θ1.

[0008] The second angle detection mechanism includes a second rotating part and a second photoelectric part. The second rotating part is disposed on the output component and can rotate with the output component. The second photoelectric part is disposed on the fixed component and can rotate relative to the second rotating part to obtain the second relative rotation angle θ2.

[0009] The harmonic reducer also includes a power supply device, which is disposed on the wave generator and / or the fixed component, and is electrically connected to the early warning device.

[0010] The power supply device includes a power generation mechanism, which is mounted on the wave generator and can convert the mechanical energy of the wave generator into electrical energy. The power generation mechanism is electrically connected to the early warning device.

[0011] The power supply device includes an energy storage mechanism, which is electrically connected to both the early warning device and the power generation mechanism.

[0012] The power supply device includes an energy storage mechanism that is electrically connected to the early warning device; and / or, the power supply device includes a power supply wire that is electrically connected to the early warning device at one end and located outside the harmonic reducer and electrically connected to an external power source at the other end.

[0013] The harmonic reducer is connected to the external power supply mechanism via a transmission, and the early warning device is electrically connected to the external power supply mechanism.

[0014] Another aspect of the present invention provides a method for determining the lifespan of the above-mentioned harmonic reducer, comprising:

[0015] Step S1: Obtain the angle data signals at the input and output ends of the harmonic reducer;

[0016] Step S2: Perform life failure early warning based on angle data signals.

[0017] The early warning device includes a first angle detection mechanism, a second angle detection mechanism, and a data analysis mechanism. The first angle detection mechanism is capable of acquiring a first relative rotation angle θ1 between the wave generator and the fixed component. The second angle detection mechanism is capable of acquiring a second relative rotation angle θ2 between the fixed component and the output component. The data analysis mechanism is capable of acquiring the first relative rotation angle θ1 and the second relative rotation angle θ2 and deriving the angle data signal. In step S1, the device further includes:

[0018] The first angle detection mechanism is controlled to obtain the first relative rotation angle θ1, and the second angle detection mechanism is controlled to obtain the second relative rotation angle θ2;

[0019] The data analysis agency obtains the first relative rotation angle θ1 and the second relative rotation angle θ2, and derives the angle data signal.

[0020] Step S2 also includes:

[0021] The angle data signal is sequentially subjected to discrete Fourier transform and penalty function processing to generate a transmission error frequency-amplitude curve.

[0022] In the frequency-amplitude curve of the transmission error, a frequency-doubled amplitude Q is proposed, and Q is made to be similar to a preset frequency-doubled amplitude K.

[0023] If Q ≥ 4.5K, then the harmonic reducer is about to fail.

[0024] Another aspect of the present invention provides a robot including the above-described harmonic reducer or a lifespan determination method using the above-described harmonic reducer.

[0025] The harmonic reducer and its lifespan determination method, robot, and early warning device of the present invention can acquire the angle data signal of the harmonic reducer and compare it with a preset value. Furthermore, the device performs transmission error characteristic frequency analysis based on the angle data signal to obtain the amplitude of twice the frequency and compares it with the preset value. The early warning device can provide a lifespan failure warning when the amplitude of twice the frequency exceeds the preset value (i.e., the harmonic reducer performance is distorted and the entire machine is about to fail), thus avoiding safety accidents and significant economic losses caused by reducer failure and ensuring the reliable operation of the harmonic reducer. Attached Figure Description

[0026] Figure 1 This is a cross-sectional view of a harmonic reducer according to an embodiment of the present invention;

[0027] Figure 2 yes Figure 1 A partial schematic diagram of point A;

[0028] Figure 3 yes Figure 1 A partial schematic diagram of point B;

[0029] Figure 4 yes Figure 1 A partial schematic diagram at point C;

[0030] Figure 5 This is a flowchart of the life determination method for a harmonic reducer according to an embodiment of the present invention;

[0031] Figure 6 This is a logic block diagram of the life monitoring of the harmonic reducer according to an embodiment of the present invention;

[0032] Figure 7 This is the frequency-amplitude curve of the harmonic reducer according to an embodiment of the present invention;

[0033] Figure 8 This is a graph showing the relationship between the lifespan and frequency amplitude of the harmonic reducer according to an embodiment of the present invention;

[0034] Legend: 1. Rigid wheel; 2. Flexible wheel; 3. Wave generator; 41. Flexible wheel flange; 42. Rigid wheel flange; 43. Cross roller bearing; 51. First angle detection mechanism; 52. Second angle detection mechanism; 6. Power generation mechanism; 7. Energy storage mechanism. Detailed Implementation

[0035] The present invention will be further described below with reference to embodiments, but is not limited to the contents of the specification.

[0036] Harmonic reducers, due to their unique flexible components and multi-tooth meshing characteristics, possess a certain degree of error balancing compensation, generally exhibiting higher transmission accuracy compared to other types of reducers. In harmonic transmission error spectrum analysis, the main error contribution manifests as high-frequency characteristics related to the rotational frequency of the rigid-flexible gear pair, characterized by a frequency of twice the normal frequency. The transmission error is the difference between the theoretically expected rotation angle and the actual rotation angle when the input shaft rotates in one direction during operation; i.e., the angle data signal. Therefore, this invention discloses a... Figures 1 to 8 The harmonic reducer shown includes a rigid wheel 1, a flexible wheel 2, a wave generator 3, and an early warning device. The flexible wheel 2 is sleeved on the outer periphery of the wave generator 3 and meshes with the rigid wheel 1. One of the flexible wheel 2 and the rigid wheel 1 constitutes a fixed component, and the other constitutes an output component. The early warning device is mounted on the fixed component and can acquire the angle data signal of the harmonic reducer and provide a lifespan failure warning based on the angle data signal. The early warning device can acquire the angle data signal of the harmonic reducer and compare it with a preset value. Furthermore, it performs transmission error characteristic frequency analysis based on the angle data signal to obtain the amplitude of twice the frequency and compares it with the preset value. The early warning device can provide a lifespan failure warning when the amplitude of twice the frequency exceeds the preset value (i.e., the harmonic reducer performance is distorted and the entire machine is about to fail), thus avoiding safety accidents and significant economic losses caused by reducer failure and ensuring the reliable operation of the harmonic reducer.

[0037] Taking a rigid wheel 1 as the output component and a flexible wheel 2 as the fixed component as an example, the harmonic reducer also includes a cross roller bearing 43, a flexible wheel flange 41, and a rigid wheel flange 42. The lower end face of the cross roller bearing mates with the upper end face of the flexible wheel flange 41 of the top-hat shaped flexible wheel 2. The lower end face of the flexible wheel flange 41 of the top-hat shaped flexible wheel 2 is connected to the flexible wheel flange 41 to form a fixed end. The upper end face of the cross roller bearing mates with the lower end face of the rigid wheel 1 as the load output end. The wave generator 3 is composed of a hollow shaft, a flexible bearing, and a rigid bearing assembly. The wave generator 3 is installed in the inner hole of the top-hat shaped flexible wheel 2, and the cylindrical surface of the wave generator 3 protrudes through the flexible wheel flange 41 to form a drive input end. The upper end face of the rigid wheel 1 is connected to the rigid wheel flange 42 as the load output end flange. The connection between the flexible wheel flange 41, the cross roller bearing 43, the rigid wheel 1, the rigid wheel flange 42, and the flexible wheel 2 is fastened with cylindrical head screws. The assembly of the harmonic reducer is thus completed.

[0038] The angle data signal is equal to the actual measured input angle divided by the transmission ratio and minus the output angle. To measure the input and output angles, the early warning device includes a first angle detection mechanism 51, a second angle detection mechanism 52, and a data analysis mechanism (monitoring module). The first angle detection mechanism 51 can acquire the first relative angle θ1 between the wave generator 3 and the fixed component; the second angle detection mechanism 52 can acquire the second relative angle θ2 between the fixed component and the output component; and the data analysis mechanism can acquire the first relative angle θ1 and the second relative angle θ2 and derive the angle data signal. When using a harmonic reducer, the drive mechanism is connected to the rotating shaft of the wave generator 3. At this time, the first relative rotation angle θ1 constitutes the input rotation angle of the harmonic reducer. During operation, due to the compression of the flexible wheel 2 by the wave generator 3, relative rotation occurs between the flexible wheel 2 and the rigid wheel 1. Whether the flexible wheel 2 or the rigid wheel 1 is the output component, relative rotation will occur between them. The second relative rotation angle θ2 then constitutes the output rotation angle of the harmonic reducer. The data analysis mechanism can, based on the first and second relative rotation angles θ1 and θ2, and the transmission ratio of the harmonic reducer, use the discrete Fourier transform principle to transform the discrete sampling points in the time domain into discrete points in the frequency domain, calculate the characteristic frequency of the transmission error, and then, through penalty function processing, delete abnormal characteristic frequency points. This generates a transmission error frequency-amplitude curve and extracts the twice-frequency amplitude Q. Figure 7 As shown; different models of reducers underwent life running-in, and the dynamic data of the second-order frequency amplitude and lifespan were monitored. The relationship between the prototype lifespan and frequency amplitude is as follows. Figure 8 As shown, the relationship between the prototype's lifespan and the amplitude of the second harmonic frequency is analyzed: the amplitude of the second harmonic frequency in the initial state is K, which is within the range of the amplitude of the second harmonic frequency of the theoretical transmission error, i.e., 2≤K≤6. The amplitude of the second harmonic frequency in the working state of the reducer is Q. As the amplitude of the second harmonic frequency Q increases, the slope of the curve relating lifespan and the amplitude of the second harmonic frequency increases, and the lifespan of the reducer decays faster. If Q≥4.5K, the transmission error of the harmonic reducer is abnormally large, the performance is distorted, and the lifespan is about to fail. Based on the aforementioned theory, the data analysis agency can provide a lifespan failure warning for the harmonic reducer to ensure its reliability.

[0039] In one embodiment, the first angle detection mechanism 51 includes a first rotating part and a first photoelectric part. The first rotating part is disposed on the wave generator 3 and can rotate with the wave generator 3. The first photoelectric part is disposed on the fixed component, and the first rotating part and the first photoelectric part can rotate relative to each other to obtain the first relative rotation angle θ1. Each time the wave generator 3 rotates one revolution, the first rotating part also rotates one revolution, and the signal of the first photoelectric part changes. The signal change is processed by the signal processing element into a numerical signal of the rotation angle, thus completing one acquisition of angle data, thereby obtaining the first relative rotation angle θ1. Preferably, the first angle detection mechanism 51 is a circular grating angle sensor or an angle encoder, that is, a high-precision circular grating angle sensor integrated at the input end.

[0040] The second angle detection mechanism 52 includes a second rotating part and a second photoelectric part. The second rotating part is disposed on the output component and can rotate with the output component. The second photoelectric part is disposed on the fixed component, and the second rotating part and the second photoelectric part can rotate relative to each other to obtain the second relative angle θ2. Each time the output component rotates one revolution, the second rotating part also rotates one revolution, and the second photoelectric part can collect angle data once to obtain the second relative angle θ2. Preferably, the second angle detection mechanism 52 is a circular grating angle sensor or an angle encoder, that is, a high-precision circular grating angle sensor integrated at the output end.

[0041] Since both the early warning devices (e.g., the first angle detection mechanism 51 and the second angle detection mechanism 52) require electrical energy during operation, the harmonic reducer also includes a power supply device. This power supply device is mounted on the wave generator 3 and / or the fixed component, and is electrically connected to the early warning device. The power supply device provides power to the early warning device to ensure its normal operation.

[0042] In one embodiment, the power supply device includes a power generation mechanism 6, which is mounted on the wave generator 3 and converts the mechanical energy of the wave generator 3 into electrical energy. The power generation mechanism 6 is electrically connected to the early warning device. The power generation mechanism 6 includes a rotor and coil windings. The rotation of the wave generator 3 drives the permanent magnet rotor inside the power generation mechanism 6 to rotate. The permanent magnet rotor continuously rotates within the annular coil windings, cutting the magnetic field and generating current, thus realizing the conversion of mechanical energy into electrical energy. The power supply device also includes an energy storage mechanism, which is electrically connected to both the early warning device and the power generation mechanism 6. The electrical energy generated by the power generation mechanism 6 can be stored in the energy storage mechanism and then transmitted to the early warning device via wires to power it.

[0043] Alternatively, the power supply device may only have an energy storage mechanism 7, which is electrically connected to the early warning device. The energy storage mechanism 7 may be a lead-acid battery, a nickel-based battery, a lithium battery, etc., and may be charged by connecting an external power source to the outside of the harmonic reducer.

[0044] Alternatively, the power supply device includes a power supply wire, one end of which is electrically connected to the warning device, and the other end is located outside the harmonic reducer and electrically connected to an external power source. In use, the harmonic reducer is fixed in a preset position, so the power supply wire can be threaded through the harmonic reducer to supply power to the warning device.

[0045] When using a harmonic reducer, the reducer is connected to an external power supply mechanism via a transmission, and the early warning device is electrically connected to the external power supply mechanism. When the early warning device determines that the angle data signal of the harmonic reducer exceeds a preset value, it indicates that the reducer is damaged. At this time, the early warning device controls the external power supply mechanism to stop or switches the transmission between the external power supply mechanism and the harmonic reducer, thereby preventing safety accidents and significant economic losses due to damage to the harmonic reducer.

[0046] Specifically, the early warning device also includes a monitoring module, a data receiving module, a data transmission module, and an energy line group. The power generation mechanism 6 is electrically connected to the energy storage mechanism 7, the monitoring module, the data receiving module, the data transmission module, and the first angle detection mechanism 51 and the second angle detection mechanism 52 via the energy line group. The data transmission module is installed on the first angle detection mechanism 51 and the second angle detection mechanism 52, and can transmit the first relative rotation angle θ1 and the second relative rotation angle θ2 detected by the first angle detection mechanism 51 and the second angle detection mechanism 52 to the data receiving module. The data receiving module then performs analysis and calculation, and based on the analysis and processing results, the monitoring and early warning module in the monitoring module issues an early warning.

[0047] Another aspect of the present invention provides a method for determining the lifespan of the above-mentioned harmonic reducer, comprising:

[0048] Step S1: Obtain the angle data signals at the input and output ends of the harmonic reducer;

[0049] Step S2: Perform life failure early warning based on angle data signals.

[0050] The early warning device includes a first angle detection mechanism 51, a second angle detection mechanism 52, and a data analysis mechanism. The first angle detection mechanism 51 can acquire the first relative rotation angle θ1 between the wave generator 3 and the fixed component. The second angle detection mechanism 52 can acquire the second relative rotation angle θ2 between the fixed component and the output component. The data analysis mechanism can acquire the first relative rotation angle θ1 and the second relative rotation angle θ2 and derive the angle data signal. In step S1, the device further includes:

[0051] The first angle detection mechanism 51 is controlled to obtain the first relative rotation angle θ1, and the second angle detection mechanism 52 is controlled to obtain the second relative rotation angle θ2;

[0052] The data analysis agency obtains the first relative rotation angle θ1 and the second relative rotation angle θ2, and derives the angle data signal.

[0053] Step S2 also includes:

[0054] The angle data signal is sequentially subjected to discrete Fourier transform and penalty function processing to generate a transmission error frequency-amplitude curve.

[0055] In the frequency-amplitude curve of the transmission error, a frequency-doubled amplitude Q is proposed, and Q is made to be similar to a preset frequency-doubled amplitude K.

[0056] If Q ≥ 4.5K, then the harmonic reducer is about to fail.

[0057] The data analysis unit has a built-in transmission error analysis program. The first relative rotation angle θ1 and the second relative rotation angle θ2 of the harmonic reducer, as well as the transmission ratio i of the harmonic reducer, are input into the program. Then, using the discrete Fourier transform principle, the discrete sampling points in the time domain are transformed into discrete points in the frequency domain to calculate the characteristic frequency of the transmission error. After processing with a penalty function, abnormal characteristic frequency points are deleted. A transmission error frequency-amplitude curve is calculated and the amplitude Q at twice the frequency is extracted. Figure 7 As shown.

[0058] Harmonic reducers, due to their unique flexible components and multi-tooth meshing characteristics, possess a certain degree of error balancing compensation, generally exhibiting higher transmission accuracy compared to other types of reducers. In harmonic transmission error spectrum analysis, the main error contribution manifests as high-frequency characteristics related to the rotational frequency of the rigid-flexible gear pair, characterized by a double frequency. Transmission error is the difference between the theoretically expected rotation angle and the actual rotation angle when the input shaft rotates in one direction during operation; this is the angle transmission error. The theoretical rotation angle equals the actual measured input rotation angle divided by the transmission ratio minus the output rotation angle. Transmission error is one of the performance indicators of harmonic reducers, and its magnitude is a crucial factor affecting the overall performance. Abnormally large transmission errors can lead to performance distortion of the harmonic reducer, indicating impending failure. Life running-in was performed on different models of reducers, monitoring the double frequency amplitude and life dynamic data. The relationship between prototype life and frequency amplitude is as follows: Figure 8 As shown, the relationship between the prototype's lifespan and the amplitude of the second harmonic frequency is analyzed: the amplitude of the second harmonic frequency in the initial state is K, which is within the range of the amplitude of the second harmonic frequency of the theoretical transmission error, i.e., 2≤K≤6. The amplitude of the second harmonic frequency in the working state of the reducer is Q. As the amplitude of the second harmonic frequency Q increases, the slope of the curve relating lifespan and the amplitude of the second harmonic frequency increases, and the lifespan of the reducer decays faster. If Q≥4.5K, the transmission error of the harmonic reducer is abnormally large, the performance is distorted, and the lifespan is about to fail. Based on the aforementioned theory, the data analysis agency can provide a lifespan failure warning for the harmonic reducer to ensure its reliability.

[0059] Another aspect of the present invention provides a robot including the above-described harmonic reducer or a lifespan determination method using the above-described harmonic reducer.

[0060] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is impossible to exhaustively list all embodiments here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A harmonic reducer, characterized in that, The device includes a rigid wheel (1), a flexible wheel (2), a wave generator (3), and an early warning device. The flexible wheel (2) is sleeved on the outer periphery of the wave generator (3). The flexible wheel (2) meshes with the rigid wheel (1). One of the flexible wheel (2) and the rigid wheel (1) constitutes a fixed component and the other constitutes an output component. The early warning device is installed on the fixed component. The early warning device can acquire the angle data signal of the harmonic reducer and perform life failure early warning based on the angle data signal. The early warning device includes a first angle detection mechanism (51), a second angle detection mechanism (52), and a data analysis mechanism. The first angle detection mechanism (51) can obtain the first relative rotation angle θ1 between the wave generator (3) and the fixed component. The second angle detection mechanism (52) can obtain the second relative rotation angle θ2 between the fixed component and the output component. The data analysis mechanism can obtain the first relative rotation angle θ1 and the second relative rotation angle θ2 and derive the angle data signal. The first angle detection mechanism (51) includes a first rotating part and a first photoelectric part. The first rotating part is disposed on the wave generator (3) and can rotate with the wave generator (3). The first photoelectric part is disposed on the fixed component and can rotate relative to the first relative angle θ1.

2. The harmonic reducer according to claim 1, characterized in that, The second angle detection mechanism (52) includes a second rotating part and a second photoelectric part. The second rotating part is disposed on the output component and can rotate with the output component. The second photoelectric part is disposed on the fixed component and can rotate relative to the second rotating part to obtain the second relative angle θ2.

3. The harmonic reducer according to claim 1, characterized in that, The harmonic reducer also includes a power supply device, which is disposed on the wave generator (3) and / or the fixed component, and the power supply device is electrically connected to the early warning device.

4. The harmonic reducer according to claim 3, characterized in that, The power supply device includes a power generation mechanism (6), which is mounted on the wave generator (3) and can convert the mechanical energy on the wave generator (3) into electrical energy. The power generation mechanism (6) is electrically connected to the early warning device.

5. The harmonic reducer according to claim 4, characterized in that, The power supply device includes an energy storage mechanism (7), which is electrically connected to both the early warning device and the power generation mechanism (6).

6. The harmonic reducer according to claim 3, characterized in that, The power supply device includes an energy storage mechanism (7), which is electrically connected to the early warning device; and / or, the power supply device includes a power supply wire, one end of which is electrically connected to the early warning device, and the other end is located outside the harmonic reducer and electrically connected to an external power source.

7. The harmonic reducer according to claim 1, characterized in that, The harmonic reducer is connected to the external power supply mechanism via a transmission, and the early warning device is electrically connected to the external power supply mechanism.

8. A method for determining the lifespan of a harmonic reducer according to any one of claims 1 to 7, characterized in that, include: Step S1: Obtain the angle data signals at the input and output ends of the harmonic reducer; Step S2: Perform life failure early warning based on angle data signals.

9. The method for determining the lifespan of a harmonic reducer according to claim 8, characterized in that, The early warning device includes a first angle detection mechanism (51), a second angle detection mechanism (52), and a data analysis mechanism. The first angle detection mechanism (51) can acquire the first relative rotation angle θ1 between the wave generator (3) and the fixed component. The second angle detection mechanism (52) can acquire the second relative rotation angle θ2 between the fixed component and the output component. The data analysis mechanism can acquire the first relative rotation angle θ1 and the second relative rotation angle θ2 and derive the angle data signal. In step S1, the device further includes: Control the first angle detection mechanism (51) to obtain the first relative rotation angle θ1, and control the second angle detection mechanism (52) to obtain the second relative rotation angle θ2; The data analysis agency obtains the first relative rotation angle θ1 and the second relative rotation angle θ2, and derives the angle data signal.

10. The method for determining the lifespan of a harmonic reducer according to claim 8, characterized in that, Step S2 also includes: The angle data signal is sequentially subjected to discrete Fourier transform and penalty function processing to generate a transmission error frequency-amplitude curve. In the frequency-amplitude curve of the transmission error, a frequency-doubled amplitude value Q is proposed, and Q is compared with a preset frequency-doubled amplitude value K. If Q ≥ 4.5K, then the harmonic reducer is about to fail.

11. A robot, characterized in that: Includes the harmonic reducer according to any one of claims 1 to 7 or the life determination method of the harmonic reducer according to any one of claims 8 to 10.

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