WO2024027172A1 - Robot joint, encoding method, and robot - Google Patents

Abstract

A robot joint, an encoding method, and a robot. The robot joint comprises: a joint body (10); a driving module (20), disposed in the joint body (10) to drive the joint body (10) to move, wherein the driving module (20) comprises a motor mechanism and a speed reduction mechanism (3) connected to the motor mechanism; and a detection mechanism (30), connected to the driving module (20), wherein the detection mechanism (30) comprises an absolute encoder (301) disposed on the output side of the motor mechanism and a semi-absolute encoder (302) disposed on the output side of the speed reduction mechanism (3), the semi-absolute encoder (302) has a plurality of zero points when the semi-absolute encoder rotates one circle, the speed ratio m of the speed reduction mechanism (3) and the period n of the semi-absolute encoder (302) differ by one or are coprime, and m and n are both positive integers; the absolute encoder (301) is suitable for detecting first position information of the output side of the motor mechanism, and the semi-absolute encoder (302) is suitable for detecting second position information of the output side of the speed reduction mechanism (3). The robot joint reduces production and manufacturing costs while ensuring the measurement accuracy of the absolute angle of a low-speed end rotor of the speed reduction mechanism (3).

Description

Robot joints, coding methods and robots

This disclosure claims priority from the following patent applications:

A Chinese patent application was submitted to the China Patent Office on August 4, 2022, with the application number 202210931492.0, and the invention name being "Robot Joints, Coding Methods and Robots";

A Chinese patent application was submitted to the China Patent Office on August 4, 2022, with the application number 202222051589.0 and the invention name "Robot Joints, Coding Methods and Robots".

Technical field

The invention belongs to the field of robot technology, and specifically relates to a robot joint, a coding method and a robot.

Background technique

Robots have strong environmental adaptability and extremely high movement flexibility, and have wide application prospects in services, medical, education, entertainment and other industries as well as special operating situations. Large robots are relatively large in size and weight, and have higher requirements for stability and driving capabilities when walking.

Among them, the joints of the robot are generally equipped with drive modules, and the drive modules drive joint motion to realize the motion of the robot. The drive module includes a drive mechanism and a reduction mechanism. The reduction mechanism amplifies the torque of the driving force of the drive mechanism and reduces the rotation speed before outputting it. At this time, it is usually necessary to determine the absolute angle of the low-speed end rotor of the reduction mechanism.

In the existing technology, the methods for determining the absolute angle of the rotor at the low-speed end of the reduction mechanism include: 1) installing an absolute encoder at the low-speed end; 2) using a high-speed encoder and adding a battery so that the encoder does not lose power; 3 ), adding a brake mechanism to the integrated joint to keep the joint stationary in the event of power failure. However, the first solution requires high accuracy of the absolute encoder and the cost is difficult to reduce; while the second solution requires the installation of additional batteries and regular replacement; the third solution requires the addition of additional mechanisms and increases the structure. complexity, and added weight and cost.

Contents of the invention

Therefore, the technical problem to be solved by the present invention is how to reduce the manufacturing cost while ensuring the absolute angle measurement accuracy of the low-speed end rotor of the reduction mechanism.

In order to solve the above technical problems, the present invention provides a robot joint, including:

joint body;

A driving module is installed in the joint body to drive the movement of the joint body; the driving module includes a motor mechanism and a deceleration mechanism connected to the motor mechanism, and the deceleration mechanism is adapted to reduce the motor to the movement of the joint body. The driving force of the mechanism is decelerated and then output; and

A detection mechanism, connected to the drive module, is suitable for detecting the position information of at least part of the moving parts of the drive module; the detection mechanism includes an absolute encoder arranged on the output side of the motor mechanism, and an absolute encoder arranged on the deceleration A semi-absolute encoder on the output side of the mechanism. The semi-absolute encoder has multiple zero points when rotating in a full circle. The speed ratio m of the reduction mechanism and the period n of the semi-absolute encoder differ by one or are mutually prime. , m and n are both positive integers;

The absolute encoder is suitable for detecting the first position information on the output side of the motor mechanism, and the semi-absolute encoder is suitable for detecting the second position information on the output side of the reduction mechanism.

Optionally, in the above-mentioned robot joint, the motor mechanism includes a motor body and an output end connected to the motor body;

The absolute encoder is installed in the motor body or connected to the output end.

Optionally, in the above-mentioned robot joint, the absolute encoder is provided in the motor body;

The motor body includes a motor housing, a motor stator, a motor rotor and a motor drive plate arranged in the motor housing. The motor stator is fixedly connected to the motor housing, and the motor rotor can be relative to the motor housing. The motor housing rotates; the motor rotor serves as the moving component, and the absolute encoder is disposed between the motor rotor and the motor stator;

The motor drive board is connected to the absolute encoder and the semi-absolute encoder, and is adapted to receive the detection information of the absolute encoder and the semi-absolute encoder, and decode according to the detection information to obtain the The absolute angle of the output side of the reduction mechanism.

Optionally, in the above robot joint, the deceleration mechanism includes a first deceleration part and a second deceleration part connected to the first deceleration part, and the rotation speed of the first deceleration part is greater than that of the second deceleration part. rotation speed;

Wherein, the second deceleration part serves as the moving component, and the semi-absolute encoder is connected to the second deceleration part and is located on a side of the second deceleration part away from the first deceleration part.

Optionally, in the above-mentioned robot joint, the first deceleration member is a wave generator, and the second deceleration member is a flexspline connected to the wave generator;

or

The first reduction component is a first reduction gear, the second reduction component is a second reduction gear, and the first reduction gear meshes with the second reduction gear.

Optionally, the above-mentioned robot joint further includes an output mechanism, and the output mechanism is fixedly connected to the second reduction member.

Optionally, in the above robot joint, the output mechanism includes an output flange.

Optionally, in the above-mentioned robot joint, the output end is fixedly connected to the first reduction member, and is suitable for transmitting the driving force of the motor body to the first reduction member.

Optionally, in the above-mentioned robot joint, the absolute encoder and the semi-absolute encoder are any one of a magnetic encoder, an optical encoder and a capacitive encoder.

The invention also provides a robot, including:

organism;

Robot joints, connected to the body;

Wherein, the robot joint is a robot joint as described above.

The present invention also provides a coding method for a robot joint, which is used for the robot joint as mentioned above. The method includes the following steps:

Utilize a detection mechanism to obtain position information of at least some moving parts of the drive module;

Based on the position information, the absolute position information of the driving module is obtained through a vernier caliper calculation method.

Optionally, in the above method, the driving module includes a motor mechanism and a reduction mechanism connected to the motor mechanism;

The position information includes first position information on the output side of the motor mechanism and second position information on the output side of the reduction mechanism;

The detection mechanism includes an absolute encoder provided on the output side of the motor mechanism and a semi-absolute encoder provided on the output side of the deceleration mechanism. The semi-absolute encoder has multiple zero points during a full rotation, so The absolute encoder is suitable for detecting the first position information on the output side of the motor mechanism, and the semi-absolute encoder is suitable for detecting the second position information on the output side of the reduction mechanism.

Optionally, in the above method, the absolute position information of the output side of the driving module is obtained through a vernier caliper calculation method based on the position information, including:

Driving the speed ratio M of the reduction mechanism and the period N of the semi-absolute encoder;

When the difference between the numbers m and n is one, the absolute position information of the output side of the reduction mechanism is:
θ=α-β;

Or, when m and n are prime numbers to each other, the absolute position information of the output side of the reduction mechanism is:
θ=aα-bβ;

Among them, θ is the absolute position of the output side of the reduction mechanism, ɑ and β are the degrees of the absolute encoder and semi-absolute encoder respectively, and a and b are positive integers.

The technical solution provided by the present invention has the following advantages: by providing a detection mechanism in the robot joint, the detection mechanism is suitable for detecting the position information of at least part of the moving parts in the drive module, so that the drive plate of the drive module is based on the position. The information calculates the absolute position information of at least part of the moving parts of the drive module without adding additional devices to ensure the compactness of the overall structure of the robot joint and does not increase the weight of the robot joint; and, the detection mechanism includes a detection mechanism provided on the motor An absolute encoder on the output side of the mechanism, and a semi-absolute encoder arranged on the output side of the reduction mechanism. The absolute encoder is suitable for detecting the first information on the output side of the motor mechanism, and the semi-absolute encoder is suitable for detecting the second information on the output side of the reduction mechanism. information, so that the absolute position information of at least some moving parts can be obtained through the cooperation of the two. Semi-absolute encoders and absolute encoders are both universal, and there is no need to use a specific encoder to increase costs.

Description of the drawings

In order to more clearly explain the specific embodiments of the present invention or the technical solutions in the prior art, the drawings that need to be used in the description of the specific embodiments or the prior art will be briefly introduced below. It is obvious that the drawings in the following description These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting creative efforts.

Figure 1 is a module block diagram of the robot joint of the present invention;

Figure 2 is a block diagram of the connection module of the driving module and detection mechanism of the present invention;

Figure 3 is a flow chart of the coding method of robot joints of the present invention.

Explanation of reference symbols:
10-joint body; 20-drive module; 30-detection mechanism; 301-absolute encoder; 302-semi-absolute encoder;
1-Motor body; 11-Motor stator; 12-Motor rotor; 2-Output end; 3-Reduction mechanism; 31-First reduction part; 32-Second reduction part; 4-Output mechanism.

Detailed ways

The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some, not all, of the embodiments of the present invention. The present invention will be described in detail below with reference to the accompanying drawings and embodiments. It should be noted that, to the extent that there is no conflict, the embodiments of the present invention and the specific features in the embodiments are Characteristics can be combined with each other.

It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

In the present invention, unless otherwise specified, the directional words used such as "up, down, top, bottom" usually refer to the direction shown in the drawings, or refer to the vertical or vertical position of the component itself. Vertically or in the direction of gravity; similarly, for ease of understanding and description, "inside and outside" refers to the inside and outside relative to the outline of each component itself, but the above directional terms are not used to limit the present invention.

Example 1

Please refer to Figure 1 and Figure 2. This embodiment provides a robot joint, which can be: when the robot is a humanoid robot, the joint is a power structure at the driving legs and driving arms; when the robot is a quadruped robot, the joint The joint is the dynamic structure that drives the leg. Taking the driving leg as an example, the power structure is provided with a driving module 20. The driving module 20 can enable the driving leg to perform actions such as opening, rotating, and knee bending.

Specifically, the robot joint includes a joint body 10 and a drive module 20 installed in the joint body 10. The drive module 20 drives the joint body 10 to move. The drive module 20 includes a motor mechanism and a reduction mechanism 3 connected to the motor mechanism. The reduction mechanism 3 is suitable for reducing the speed of the driving force of the motor mechanism and increasing the torque for output.

The motor mechanism includes a motor body 1 and an output end 2 connected to the motor body 1 . The output end 2 is connected to the reduction mechanism 3 to transmit the driving force of the motor body 1 to the reduction mechanism 3 . Specifically, the motor body 1 includes a motor casing, a motor stator 11 disposed in the motor casing, a motor rotor 12 and a motor drive board. The motor drive board is electrically connected to the motor stator 11 and the motor rotor 12 respectively. Among them, the motor stator 11 is fixedly arranged in the motor casing and is fixedly connected to the motor casing. The motor rotor 12 is arranged in the motor casing and can rotate relative to the motor casing. The motor rotor 12 is connected to the output end 2, suitable for To drive the output end 2 to rotate and thereby output torque.

The deceleration mechanism 3 includes a first deceleration part 31 and a second deceleration part 32 connected to the first deceleration part 31 . The rotation speed of the first deceleration part 31 is greater than the rotation speed of the second deceleration part 32 . By providing the first reduction member 31 and the second reduction member 32 and causing the rotational speeds of the first reduction member 31 and the second reduction member 32 to form a rotational difference, the driving speed of the motor mechanism is reduced.

As can be seen from the above, the motor body 1 is connected to the reduction mechanism 3 through the output end 2 to transmit the driving force of the motor body 1 to the reduction mechanism 3. Therefore, the output end 2 is fixedly connected to the first reduction member 31, which is suitable for the motor body. The driving force of 1 is transmitted to the first reduction member 31.

In one embodiment, the first deceleration member 31 is a wave generator, and the second deceleration member 32 is a flexspline connected to the wave generator. At this time, the reduction mechanism 3 also includes a rigid wheel meshed with a flexspline, and the reduction mechanism 3 is a harmonic reducer. Ganglun Fixedly connected to the joint body 10.

Specifically, the wave generator is installed in the flexspline, and the first teeth are provided on the outer surface of the flexspline. The rigid spline is sleeved on the flex spline, and the inner surface of the rigid spline facing the outer surface of the flex spline is provided with second teeth meshing with the first teeth.

The wave generator causes radial deformation of the flexspline. When the wave generator is installed into the flexspline, it forces the cross-section of the flexspline to change from the original circle to an elliptical shape. The first teeth near both ends of the long axis of the flexspline are fully meshed with the second teeth of the rigid spline, and The first teeth near both ends of the short axis of the flexspline are completely separated from the second teeth of the rigid spline. The first teeth of other sections on the circumference of the flexspline are in a transitional state of engagement and disengagement. When the wave generator continues to rotate, the deformation of the flexspline continues to change, so that the meshing state of the flexspline and the rigid spline also continuously changes, from meshing in, meshing, meshing out, disengaging, meshing again..., and it proceeds over and over again. This enables the flexspline to rotate slowly relative to the rigid spline.

In another embodiment, the first reduction component 31 is a first reduction gear, the second reduction component 32 is a second reduction gear, and the first reduction gear meshes with the second reduction gear. That is, in this embodiment, the reduction mechanism 3 is a gear reduction box. The above-mentioned first reduction gear and the second reduction gear may be a gear set or an integrated gear, for example, two gears with different diameters are fixedly connected up and down or integrally formed up and down. The gear reduction box has a conventional structure and will not be described in detail here.

The robot joint also includes an output mechanism 4, which is fixedly connected to the second deceleration member 32. The second deceleration member 32 is adapted to transmit the decelerated driving force to the output mechanism 4, thereby driving the joint body 10 to move. In this embodiment, the output mechanism 4 includes an output flange.

Among them, the motor mechanism in the robot joint is output after the torque is amplified by the reduction mechanism 3 and the rotation speed is reduced. It is usually necessary to determine the absolute angle of the low-speed end rotor. As can be seen from the foregoing, the motor mechanism decelerates after passing through the reduction mechanism 3 , so the low-speed end rotor is the output side of the reduction mechanism 3 .

In the prior art, in order to measure the absolute angle of the rotor at the low speed end, an absolute encoder 301 is generally installed at the low speed end. However, the installed absolute encoder 301 has high accuracy requirements and the cost is difficult to reduce. Or, use a high-speed encoder and a power supply battery. The power supply battery supplies power to the high-speed encoder so that the high-speed encoder does not lose power. However, such a setup requires additional batteries and regular battery replacement. Alternatively, a brake mechanism can be added to the robot joints to keep the robot joints stationary in the event of power failure. However, this requires adding additional structures, which increases the complexity of the overall structure of the robot joint, and also increases the overall weight and cost of the robot joint.

In order to solve the above technical problems and reduce costs while ensuring the accuracy of the absolute angle measurement results of the low-speed rotor, the robot joint in this embodiment also includes a detection mechanism 30, and the detection mechanism 30 is connected to the drive module 20. It is suitable for detecting the position information of at least part of the moving parts of the driving module 20 .

Specifically, the detection mechanism 30 includes an absolute encoder 301 disposed on the output side of the motor mechanism, and an absolute encoder 301 disposed on the deceleration Semi-absolute encoder 302 on the output side of mechanism 3. Among them, the semi-absolute encoder 302 has N periodic signals, and evenly distributes a circle of 360°. When the semi-absolute encoder 302 rotates a circle (360°), there are multiple zero points; the absolute encoder 301 is: In the same cycle, the output signal and the angle information are in one-to-one correspondence, and the absolute encoder 301 has only one zero point for one revolution (360°). In this embodiment, the absolute encoder 301 is suitable for detecting the first position information on the output side of the motor mechanism, and the semi-absolute encoder 302 is suitable for detecting the second position information on the output side of the reduction mechanism 3 .

Furthermore, in this embodiment, the absolute encoder 301 and the semi-absolute encoder 302 are any of a magnetic encoder, an optical encoder, and a capacitive encoder. It can be seen that in this embodiment, by providing a conventional absolute encoder 301 on the output side of the motor mechanism and a conventional semi-absolute encoder 302 on the output side of the reduction mechanism 3, it is possible to ensure that the detected low-speed end rotor is While achieving absolute angle accuracy, it can also reduce production costs.

As can be seen from the foregoing, the absolute encoder 301 is disposed on the output side of the motor mechanism to detect the first position information on the output side of the motor mechanism. Therefore, the absolute encoder 301 is disposed in the motor body 1 or connected to the output end 2 . In this embodiment, the absolute encoder 301 is provided in the motor body 1 . The output side of the motor body 1 is the motor rotor 12 . At this time, the motor rotor 12 serves as a moving component, and the absolute encoder 301 is disposed between the motor rotor 12 and the motor stator 11 .

Correspondingly, the semi-absolute encoder 302 is disposed on the output side of the reduction mechanism 3 to detect the second position information of the semi-absolute encoder 302 . In this embodiment, the second reduction member 32 serves as a moving component, and the semi-absolute encoder 302 is connected to the second reduction member 32 and is located on the side of the second reduction member 32 away from the first reduction member 31 . Among them, the deceleration mechanism 3 also includes a deceleration housing connected to the joint body 10. The first deceleration part 31 and the second deceleration part 32 are both disposed in the deceleration housing. The semi-absolute encoder 302 is disposed between the second deceleration part 32 and the deceleration part 32. between shells.

In this embodiment, the speed ratio of the reduction mechanism 3 is m, so that when the second reduction member 32 rotates for one cycle, the absolute encoder 301 provided in the motor body 1 will generate m periodic signals. The second reduction member 32 is provided with a semi-absolute encoder 302 with a period of n. Among them, m and n differ by one, or m and n are relatively prime.

As can be seen from the foregoing, the motor mechanism includes a motor drive board, wherein the motor drive boards are connected to the absolute encoder 301 and the semi-absolute encoder 302, and are suitable for receiving the first position information detected by the absolute encoder 301 and the semi-absolute encoder 302. The second position information is detected and decoded according to the first position information and the second position information to obtain the absolute angle of the output side of the deceleration mechanism 3 . Therefore, this application uses an absolute encoder 301 on the output side of the motor mechanism and a semi-absolute encoder 302 on the output side of the reduction mechanism 3. The motor drive board simultaneously receives the detection information of the absolute encoder 301 and the semi-absolute encoder 302. , the absolute encoder 301 and the semi-absolute encoder 302 together form a vernier caliper type absolute encoder 301, which can obtain the absolute angle of the low-speed rotor through simple decoding calculations.

Among them, the above-mentioned decoding calculation specifically includes:

The first position information detected by the absolute encoder 301 is:
θm＝2πk ₁ +α

The second position information detected by the semi-absolute encoder 302 is:
θn＝2πk ₂ +β

Among them, m is the speed ratio of the reduction mechanism 3, n is the period of the semi-absolute encoder 302, ɑ and β are the degrees (0~2π) of the absolute encoder 301 and the semi-absolute encoder 302 respectively, k ₁ and k ₂ respectively is the number of completed cycles that the absolute encoder 301 and the semi-absolute encoder 302 have traveled relative to the zero point, and θ is the absolute angle of the low-speed end rotor. To simplify the proof process, the zero position of θ is set at a position where the absolute encoder 301 and the semi-absolute encoder 302 are at the zero position at the same time.

Since m and n are prime numbers to each other, according to Pei Shu's theorem, we can find two positive integers a and b, such that:
|am-bn|=1

Correspondingly, the absolute angle of the low-speed rotor is:
θ＝(am-bn)θ＝2aπk ₁ +aα-2bπk ₂ -bβ＝2π(ak ₁ -bk ₂ )+(aα-bβ)

Since a, b, k ₁ and k ₂ are all positive integers, 2π (ak ₁ -bk ₂ ) in the above formula has no effect on the absolute angle of the low-speed rotor and can be ignored. Therefore, the final absolute angle of the low-speed rotor is :
θ=aα-bβ

As can be seen from the above, m and n can differ by one. In order to simplify the calculation process, select a=b=1 or a=b=-1. At this time, the final absolute angle of the low-speed rotor is:
θ=α-β

It can be seen from the above decoding calculation that by providing an absolute encoder 301 on the output side of the motor mechanism and a semi-absolute encoder 302 on the output side of the reduction mechanism 3, the calculation process of the absolute angle of the rotor at the low speed end can be simplified and the low speed end can be ensured. Calculation accuracy of the absolute angle of the rotor.

To sum up, by disposing the detection mechanism 30 in the robot joint, the detection mechanism 30 is suitable for detecting the position information of at least part of the moving parts in the drive module 20, so that the drive plate of the drive module 20 calculates based on the position information. The absolute position information of at least some of the moving parts of the drive module 20 does not require the addition of additional components to ensure the compactness of the overall structure of the robot joint and does not increase the weight of the robot joint; and, the detection mechanism 30 includes a component provided on the motor The absolute encoder 301 on the output side of the mechanism, and the semi-absolute encoder 302 provided on the output side of the reduction mechanism 3. The absolute encoder 301 is suitable for detecting the first information on the output side of the motor mechanism, and the semi-absolute encoder 302 is suitable for detecting The second information on the output side of the reduction mechanism 3 is used to obtain the absolute position information of at least part of the moving parts through the cooperation of the two. Both the semi-absolute encoder 302 and the absolute encoder 301 are universal, and there is no need to use a specific encoder to increase the number of moving parts. cost.

Example 2

This embodiment provides a robot, which includes a body and robot joints connected to the body. The robot joints can open, rotate, knee-bend and other actions driven by the driving module 20 to meet different needs of the robot. Wherein, the robot joint is the robot joint in the above-mentioned Embodiment 1.

Example 3

Please refer to Figure 3. This embodiment provides a coding method for a robot joint, which is used for the robot joint in the above-mentioned Embodiment 1. The method includes the following steps:

Step 310, use the detection mechanism 30 to obtain the position information of at least some moving parts of the drive module 20;

Step 320: Based on the position information, obtain the absolute position information of the driving module 20 through a vernier caliper calculation method.

Among them, as can be seen from the above-mentioned Embodiment 1, the driving module 20 includes a motor mechanism and a reduction mechanism 3 connected to the motor mechanism. Correspondingly, the position information includes the first position information on the output side of the motor mechanism and the second position information on the output side of the reduction mechanism 3 .

The detection mechanism 30 includes an absolute encoder 301 disposed on the output side of the motor mechanism, and a semi-absolute encoder 302 disposed on the output side of the reduction mechanism 3. The semi-absolute encoder 302 has multiple zero points when rotating in a full circle. The absolute encoder The encoder 301 is suitable for detecting the first position information on the output side of the motor mechanism, and the semi-absolute encoder 302 is suitable for detecting the second position information on the output side of the reduction mechanism 3 .

Based on the position information, the absolute position information of the output side of the drive module 20 is obtained through a vernier caliper calculation method, including:

The speed ratio m of the drive reduction mechanism 3 and the period n of the semi-absolute encoder 302; when the difference between the numbers of m and n is one, the absolute position information on the output side of the reduction mechanism 3 is:
θ=α-β;

Or, when m and n are prime numbers to each other, the absolute position information of the output side of the reduction mechanism 3 is:
θ=aα-bβ;

Among them, θ is the absolute position of the output side of the reduction mechanism 3 (the absolute angle of the low-speed end rotor), ɑ and β are the degrees of the absolute encoder 301 and the semi-absolute encoder 302 respectively, and a and b are positive integers.

The above-mentioned specific calculation process is the same as the decoding calculation of the absolute angle of the low-speed end rotor in the above-mentioned Embodiment 1, and will not be described again in this embodiment.

Obviously, the above-described embodiments are only part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, those of ordinary skill in the art can make other changes or modifications in different forms without making creative efforts, and all of them shall fall within the scope of protection of the present invention.

Claims (16)

A robot joint is characterized by including: joint body; A driving module is installed in the joint body to drive the movement of the joint body; the driving module includes a motor mechanism and a deceleration mechanism connected to the motor mechanism, and the deceleration mechanism is adapted to reduce the motor to the movement of the joint body. The driving force of the mechanism is decelerated and then output; and A detection mechanism, connected to the drive module, is suitable for detecting the position information of at least part of the moving parts of the drive module; the detection mechanism includes an absolute encoder arranged on the output side of the motor mechanism, and an absolute encoder arranged on the deceleration A semi-absolute encoder on the output side of the mechanism. The semi-absolute encoder has multiple zero points when rotating in a full circle. The speed ratio m of the reduction mechanism and the period n of the semi-absolute encoder differ by one or are mutually prime. , m and n are both positive integers; The absolute encoder is suitable for detecting the first position information on the output side of the motor mechanism, and the semi-absolute encoder is suitable for detecting the second position information on the output side of the reduction mechanism. The robot joint according to claim 1, wherein the motor mechanism includes a motor body and an output end connected to the motor body; The absolute encoder is installed in the motor body or connected to the output end. The robot joint of claim 2, wherein the absolute encoder is disposed within the motor body; The motor body includes a motor housing, a motor stator, a motor rotor and a motor drive plate arranged in the motor housing. The motor stator is fixedly connected to the motor housing, and the motor rotor can be relative to the motor housing. The motor housing rotates; the motor rotor serves as the moving component, and the absolute encoder is disposed between the motor rotor and the motor stator; The motor drive board is connected to the absolute encoder and the semi-absolute encoder, and is adapted to receive the detection information of the absolute encoder and the semi-absolute encoder, and decode according to the detection information to obtain the The absolute angle of the output side of the reduction mechanism. The robot joint of claim 3, wherein the deceleration mechanism includes a first deceleration part and a second deceleration part connected to the first deceleration part, and the rotation speed of the first deceleration part is greater than that of the second deceleration part. The rotation speed of the reduction part; Wherein, the second deceleration part serves as the moving component, and the semi-absolute encoder is connected to the second deceleration part and is located on a side of the second deceleration part away from the first deceleration part. The robot joint of claim 4, wherein the first deceleration member is a wave generator, and the second deceleration member is a flexspline connected to the wave generator; or The first reduction component is a first reduction gear, the second reduction component is a second reduction gear, and the first reduction gear meshes with the second reduction gear. The robot joint according to claim 5, wherein the deceleration mechanism 3 further includes a rigid wheel meshed with a flexspline, the rigid wheel is fixedly connected to the joint body, the wave generator is installed in the flexspline, and the outer surface of the flexspline is provided with There are first teeth, the rigid spline is sleeved on the flex spline, and the inner surface of the rigid spline facing the outer surface of the flex spline is provided with second teeth meshing with the first teeth. The robot joint of claim 4, wherein the deceleration mechanism further includes a deceleration housing connected to the joint body, the first deceleration part and the second deceleration part are both disposed in the deceleration housing, and the semi-absolute encoder is disposed in the second deceleration housing. Between the reduction piece and the reduction housing. The robot joint of claim 3, wherein the motor drive boards are connected to the absolute encoder and the semi-absolute encoder, and are adapted to receive the first position information detected by the absolute encoder and the second position detected by the semi-absolute encoder. information, and decode according to the first position information and the second position information to obtain the absolute angle of the output side of the reduction mechanism. The robot joint according to claim 4, wherein the robot joint further includes an output mechanism, and the output mechanism is fixedly connected to the second reduction member. The robot joint of claim 9, wherein the output mechanism includes an output flange. The robot joint of claim 4, wherein the output end is fixedly connected to the first reduction member and is adapted to transmit the driving force of the motor body to the first reduction member. The robot joint according to any one of claims 1 to 11, wherein the absolute encoder and the semi-absolute encoder are any one of a magnetic encoder, an optical encoder and a capacitive encoder. A robot is characterized by including: organism; Robot joints, connected to the body; Wherein, the robot joint is the robot joint according to any one of claims 1 to 9. A coding method for robot joints, characterized in that it is used for the robot joint according to any one of claims 1 to 12, and the method includes the following steps: Utilize a detection mechanism to obtain position information of at least some moving parts of the drive module; Based on the position information, the absolute position information of the driving module is obtained through a vernier caliper calculation method. The method of claim 14, wherein the drive module includes a motor mechanism and a reduction mechanism connected to the motor mechanism; The position information includes the first position information on the output side of the motor mechanism and the second position information on the output side of the reduction mechanism. location information; The detection mechanism includes an absolute encoder provided on the output side of the motor mechanism and a semi-absolute encoder provided on the output side of the deceleration mechanism. The semi-absolute encoder has multiple zero points during a full rotation, so The absolute encoder is suitable for detecting the first position information on the output side of the motor mechanism, and the semi-absolute encoder is suitable for detecting the second position information on the output side of the reduction mechanism. The method of claim 15, wherein said obtaining the absolute position information of the output side of the driving module through a vernier caliper calculation method based on the position information includes: Driving the speed ratio m of the reduction mechanism and the period n of the semi-absolute encoder; When the difference between the numbers m and n is one, the absolute position information of the output side of the reduction mechanism is:
θ=α-β; Or, when m and n are prime numbers to each other, the absolute position information of the output side of the reduction mechanism is:
θ=aα-bβ; Among them, θ is the absolute position of the output side of the reduction mechanism, ɑ and β are the degrees of the absolute encoder and semi-absolute encoder respectively, and a and b are positive integers.