A joint module for a humanoid robot

Abstract

The utility model discloses a kind of joint module for humanoid robot, including output module, deceleration module, outer rotor motor, coding module and drive control module.Output module is used to connect to humanoid robot;Deceleration module is connected with output module;Outer rotor motor includes motor stator and the motor rotor of the outer periphery of motor stator, motor rotor is engaged in the side of deceleration module relative to output module, and can rotate relative to motor stator, motor stator includes yoke and the several tooth parts of extending from yoke towards periphery, tooth part is independent and is provided with flat body conductor with yoke, clearance is formed between adjacent two tooth parts, and flat body conductor is at least partially located in clearance;Coding module is engaged in motor rotor;Drive control module is connected with motor stator, and located the side of coding module relative to motor rotor.Compared with prior art, the utility model can realize higher torque density and slot fullness.

Description

Technical Field

[0001] This utility model relates to a joint module for humanoid robots, belonging to the field of robotics technology. Background Technology

[0002] Currently, most articulated modules on the market use frameless external rotor torque motors, whose stator windings are mostly round wire structures, and the core is formed using a one-piece stamping process. Due to the low matching degree between the round wire shape and the core slot shape, there are many gaps in the winding distribution within the slots, resulting in a slot fill factor that generally only reaches about 60%. This low slot fill factor limits the improvement of the effective conductive area of ​​the wires, thus affecting the motor's torque output capability and efficiency. At the same time, the one-piece stamped core has room for optimization in terms of magnetic circuit design and material utilization, making it difficult to further increase the motor's power density, thus hindering technological breakthroughs in lightweighting, miniaturization, and high dynamic response performance of articulated modules. Therefore, the existing structure cannot meet the urgent needs of high-performance articulated modules for high power density, high peak torque, and compact design.

[0003] In view of this, it is indeed necessary to improve the existing joint modules used in humanoid robots to solve the above problems. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model provides a joint module for humanoid robots, which can achieve higher torque density and slot fill factor.

[0005] The technical solution of this utility model is: A joint module for a humanoid robot, characterized in that it comprises: An output module is used to connect to the humanoid robot; A deceleration module is connected to the output module; An external rotor motor includes a motor stator and a motor rotor disposed on the outer periphery of the motor stator. The motor rotor meshes with the side of the reduction module opposite to the output module and is rotatable relative to the motor stator. The motor stator includes a yoke and a plurality of teeth extending from the yoke in all directions. The teeth are independent of the yoke and are provided with flat conductors. A gap is formed between two adjacent teeth, and the flat conductors are at least partially located within the gaps. An encoding module engages with the side of the motor rotor opposite to the reduction module; The drive control module is connected to the motor stator and is located on the side of the encoding module relative to the motor rotor.

[0006] As a further improvement of this utility model, the motor rotor includes a rotor housing and a drive shaft connected to the rotor housing. The motor stator is provided with a through hole for the drive shaft to pass through. A drive gear is provided at the end of the drive shaft away from the rotor housing, and the drive gear meshes with the encoding module.

[0007] As a further improvement of this utility model, a plurality of magnets are provided on the side of the rotor housing facing the motor stator, and the magnets are arranged in an array around the outer periphery of the motor stator.

[0008] As a further improvement of this utility model, the magnets are all rectangular magnets and arranged in a Halbach array.

[0009] As a further improvement of this utility model, the encoding module includes a first encoding gear and a second encoding gear, which are respectively meshed with the drive gear. The first encoding gear and the second encoding gear are provided with induction magnetic rings, and the drive control module is provided with an encoder chip adapted to the induction magnetic rings.

[0010] As a further improvement of this utility model, the drive gear is one of a PEK gear and an aluminum alloy gear, and the first and second coded gears are the other of the PEK gear and the aluminum alloy gear.

[0011] As a further improvement of this utility model, both the reduction module and the external rotor motor are provided with through holes, and the two through holes are interconnected to form a cavity. A hollow tube is provided in the cavity, and fixing members are provided on opposite sides of the hollow tube. The fixing members are used to fix the hollow tube on the reduction module and the external rotor motor, and the hollow tube is in a stationary state.

[0012] As a further improvement of this utility model, the fixing member includes a first fixing member and a second fixing member. The first fixing member is used to fix the opposite sides of the hollow tube to the reduction module and the external rotor motor respectively. The second fixing member is located between the hollow tube and the reduction module and the external rotor motor, and is used to support the opposite sides of the hollow tube. The second fixing member and the hollow tube remain relatively stationary.

[0013] As a further improvement of this utility model, the yoke is circular and has several grooves on its outer periphery, and the teeth are engaged in the grooves.

[0014] As a further improvement of this utility model, the toothed part has a retaining part that is engaged in the groove, and the retaining part is a trapezoidal structure that gradually expands outward toward the yoke.

[0015] The beneficial technical effects of this utility model are as follows: The joint module for humanoid robots of this utility model has several teeth extending outward from the yoke on the motor stator, and the teeth and yoke are designed independently to set flat conductors on the teeth, so that the motor stator is arranged in a segmented manner, which can achieve a higher slot fill factor compared with the traditional stamped motor stator. In addition, the more regular cross-section of the flat conductors can also embed more flat conductors in the same slot volume, improving the current carrying capacity, thereby increasing the torque density and peak output torque. At the same time, the higher slot fill factor means that the motor volume and weight can be reduced for the same power, which is crucial for the compactness of the robot joint. Attached Figure Description

[0016] Figure 1 This is a structural schematic diagram of a joint module for a humanoid robot that conforms to a preferred embodiment of the present invention.

[0017] Figure 2 yes Figure 1 The exploded view of the joint module shown.

[0018] Figure 3 yes Figure 2 A cross-sectional view of the combination of the Chinese and foreign rotor motors, the encoder module, and the drive control module.

[0019] Figure 4 yes Figure 3 The structure of the stator teeth and yoke of the electric motor is shown in the schematic diagram.

[0020] Figure 5 yes Figure 3 A schematic diagram of the structure of a stator using circular conductors.

[0021] Figure 6 yes Figure 3 The diagram shows a schematic of the application of flat conductors in the motor stator. Detailed Implementation

[0022] In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, the specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit the scope of this utility model.

[0023] Please see Figures 1 to 6 As shown, this utility model discloses a joint module 100 for a humanoid robot. The joint module 100 includes an output module 1, a deceleration module 2, an external rotor motor 3, an encoding module 4, and a drive and control module 5.

[0024] The output module 1 is used to connect to the humanoid robot and provide driving force to the humanoid robot. Specifically, the output module 1 includes a mounting flange 11, an output shaft 12, and a bearing 13. The output shaft 12 is used to provide driving force to the humanoid robot, the mounting flange 11 is connected to the output shaft 12 and is used to connect the output module 1 to the humanoid robot, and the bearing 13 is used to connect the output module 1 to the reduction module 2. That is, the output module 1 is connected to the reduction module 2 through the mutual cooperation of the output shaft 12 and the bearing 13, and the driving force of the output shaft 12 is transmitted to the humanoid robot through the mounting flange 11.

[0025] The reduction module 2 is connected to the output module 1. In this embodiment, the reduction module 2 is a two-stage planetary reducer, including a first-stage planetary gear set 21 and a second-stage planetary gear set 22 that mesh with each other. The second-stage planetary gear set 22 is located near the output module 1, and the first-stage planetary gear set 21 is located near the external rotor motor 3.

[0026] The external rotor motor 3 includes a motor stator 31 and a motor rotor 32 disposed on the outer periphery of the motor stator 31. The motor rotor 32 meshes with the side of the reduction module 2 opposite to the output module 1 and is capable of rotating relative to the motor stator 31.

[0027] The motor rotor 32 includes a rotor housing 321 and a drive shaft 322 connected to the rotor housing 321. The motor stator 31 has a through hole for the drive shaft 322 to pass through. A sun gear 323 is provided on the side of the drive shaft 322 near the reduction module 2, and the sun gear 323 rotates synchronously with the motor rotor 32. Preferably, the sun gear 323 meshes with the first-stage planetary gear set 21, and drives the second-stage planetary gear set 22 and the output shaft 12 to rotate synchronously through the first-stage planetary gear set 21, thereby providing driving force to the humanoid robot. A drive gear 324 is also provided on the side of the drive shaft 322 away from the reduction module 2, and the drive gear 324 meshes with the encoding module 4.

[0028] In this embodiment, a plurality of magnets 325 are provided on the side of the rotor housing 321 facing the motor stator 31. These magnets 325 are arranged in an array around the outer periphery of the motor stator 31. All magnets 325 are rectangular and arranged in a Halbach array. This Halbach array arrangement concentrates the magnetic flux generated by the magnets 325 and directs it to one side of the motor stator 31, thereby generating a stronger magnetic field in the air gap than a conventional radial magnetization array. This directly improves the torque density and power density of the external rotor motor 3. Simultaneously, this array significantly weakens the stray magnetic field on the back side of the motor rotor 32, which not only reduces the iron loss of the motor stator 31 and improves efficiency, but also effectively reduces rotor eddy current losses, thus benefiting thermal management.

[0029] Furthermore, by optimizing the geometry of the Halbach array (e.g., using curved segments) and the magnetization direction, a highly sinusoidal or ideal trapezoidal magnetic field distribution can be generated in the air gap. This reduces torque pulsation, lowers vibration noise, and improves operational smoothness.

[0030] The motor stator 31 includes a yoke 311 and a plurality of teeth 312 extending from the yoke 311 outwards. The teeth 312 are independent of the yoke 311, and flat conductors 313 are provided on the teeth 312. A gap 310 is formed between adjacent teeth 312, and the flat conductors 313 are at least partially located within the gaps 310. Preferably, the yoke 311 is circular and has a plurality of grooves 314 on its outer periphery, and the teeth 312 are engaged within the grooves 314. That is, in this embodiment, by designing the tooth 312 and the yoke 311 independently, the motor stator 31 is designed in a segmented manner. Compared with the traditional stamped one-piece motor stator 31, the flat wire 313 can be directly and tightly wound onto each individual tooth 312 first, and then these teeth 312 with the flat wire 313 are assembled onto the yoke 311. In this way, a larger slot fill factor is provided. A higher slot fill factor means that more flat wires 313 can be placed in the same volume, and a larger current can be passed through, thereby generating a stronger magnetic field and directly improving the torque and power density of the motor.

[0031] like Figure 5 As shown, the circular conductors used have gaps between their arrangement, affecting the slot fill factor. Figure 6 The flat conductor 313 shown can provide a larger slot fill factor, and a higher slot fill factor means that more flat conductors 313 can be placed in the same volume, allowing for a larger current to pass through, thereby generating a stronger magnetic field and directly improving the torque and power density of the motor.

[0032] Furthermore, in a traditional integrated motor stator 31, the wires near the bottom of the slots are tightly wrapped, making it difficult for heat to dissipate and creating localized hot spots. In the segmented design, the wires can be installed individually on the teeth 312, resulting in more regular wires. Additionally, the back of each tooth 312 (where it contacts the yoke 311) can be designed to directly contact the external heat dissipation structure, allowing heat to be more effectively conducted to the stator housing. This extends the peak power duration of the motor, improving reliability and lifespan.

[0033] Furthermore, the original integrated motor stator 31 required the installation of wires within a confined space, which was extremely cumbersome. Through a segmented design, the wire installation process is broken down into two steps: "precision winding of individual teeth" and "assembly of teeth 312 and yoke 311." The method of installing wires independently on teeth 312 is well-suited for fully automated production, significantly improving production efficiency and consistency while reducing labor costs.

[0034] In this embodiment, flat wires 313 are wound around the teeth 312, compared to the original round wires. The cross-section of the flat wires is more regular, which is more conducive to close arrangement, further reducing the gaps between the wires. According to experiments, the slot fill factor can reach more than 80%, while the original round wires are below 60%. The difference is significant. The increase in slot fill factor can improve the current carrying capacity, thereby increasing the torque density and peak output torque. In addition, when the external rotor motor 3 is running at high frequency, the flat wires 313 can reduce AC resistance by reasonably designing the width-to-thickness ratio of the cross-section (such as thin and wide wires), reducing the additional losses caused by the skin effect (especially during high-frequency PWM drive). The specific design can be adjusted according to the actual situation and is not limited thereto. Preferably, a higher slot fill factor means that the volume and weight of the external rotor motor 3 can be reduced at the same power, which is crucial for the compactness of the robot joint.

[0035] Preferably, the tooth 312 has a retaining portion 3120 that engages within the groove 314, the retaining portion 3120 being a trapezoidal structure that gradually expands outward toward the yoke 311. Preferably, the side of the retaining portion 3120 closest to the yoke 311 is the longer side of the trapezoid, and the length of the longer side is greater than the length of the cross-section of the tooth 312.

[0036] The encoding module 4 is engaged with the side of the motor rotor 32 opposite to the reduction module 2. It includes a first encoding gear 41 and a second encoding gear 42, which are respectively engaged with the drive gear 324. The first encoding gear 41 and the second encoding gear 42 are provided with induction magnetic rings, and the drive control module 5 is provided with an encoder chip adapted to the induction magnetic rings.

[0037] In this embodiment, the drive gear 324 is one of a PEK gear and an aluminum alloy gear, and the first coded gear 41 and the second coded gear 42 are the other of the PEK gear and the aluminum alloy gear.

[0038] When the drive gear 324 is an aluminum alloy gear, and the first encoding gear 41 and the second encoding gear 42 are PEEK gears, since the motor rotor 32 is the main heat source and has a high temperature, the high temperature resistance of aluminum alloy (typically exceeding 150°C) allows it to be placed closer to the heat source. Simultaneously, the aluminum alloy gear can be precisely machined directly onto the aluminum alloy body of the motor rotor 32 (for example, by machining a gear structure at one end of the inner wall of the rotor), achieving extremely high concentricity and structural rigidity. This is crucial for a drive source. Using PEEK gears in the first encoding gear 41 and the second encoding gear 42 fully utilizes the vibration reduction, noise reduction, and self-lubrication advantages of PEEK gears, making the encoder shaft rotation smoother and directly improving the quality of the feedback signal.

[0039] When the drive gear 324 is a PEEK gear and the first encoding gear 41 and the second encoding gear 42 are aluminum alloy gears, the PEEK gear is lighter and therefore more suitable when there is limited space on the motor rotor 32, making it impossible to integrate and machine an aluminum alloy gear. However, this method requires solving the heat resistance problem of the PEEK gear.

[0040] The drive control module 5 is connected to the motor stator 31 and is located on the side of the encoding module 4 opposite to the motor rotor 32. The drive control module 5 is a drive control board.

[0041] In this embodiment, both the reduction module 2 and the external rotor motor 3 are provided with through holes, which are interconnected to form a cavity. A hollow tube 6 is provided inside the cavity, and fixing members 61 are provided on opposite sides of the hollow tube 6. The fixing members 61 are used to fix the hollow tube 6 to the reduction module 2 and the external rotor motor 3, and the hollow tube 6 is in a stationary state. The hollow tube 6 is a fixed, non-rotating metal tube (usually steel or aluminum) that extends from the rear end of the external rotor motor 3 to the front end of the reduction module 2 and passes through the center of the joint module 100. The hollow tube 6 provides a protected channel for various cables (motor encoder cables, brake cables, sensor cables, and even pneumatic and hydraulic lines) to pass directly and neatly from the "fixed frame" side of the device to the "motion execution end" (i.e., the flange at the end of the robot arm).

[0042] The fixing member 61 includes a first fixing member and a second fixing member. The first fixing member is used to fix the opposite sides of the hollow tube 6 to the reduction module 2 and the external rotor motor 3, respectively. The second fixing member is located between the hollow tube 6 and the reduction module 2 and the external rotor motor 3, and is used to support the opposite sides of the hollow tube 6. The second fixing member and the hollow tube 6 remain relatively stationary. The fixing member 61 is a bearing, and includes a front bearing for fixing the hollow tube 6 to the reduction module 2, and a rear bearing for fixing the hollow tube 6 to the external rotor motor 3. Both the front bearing and the rear bearing have a first fixing member and a second fixing member. The first fixing member is the outer ring of the bearing, and the second fixing member is the inner ring of the bearing. The outer ring is used for fixing, and the inner ring is used for supporting the hollow tube 6, so that the hollow tube 6 and the rotating components such as the motor rotor 32 remain concentric and completely isolated. The rotating components operate on the outer ring of the bearing, while the hollow tube 6 and the inner ring of the bearing remain stationary.

[0043] The joint module 100 also includes a housing 200, which is used to house the reduction module 2, the external rotor motor 3, the encoding module 4, and the drive control module 5. The housing 200 includes a first housing 300, a second housing 400, and a third housing 500. The second housing 400 is connected to the motor stator 31 and serves as the base of the motor stator 31. The first housing 300 and the second housing 400 are connected to form a frame. The third housing 500 is a bottom cover used to enclose the reduction module 2, the external rotor motor 3, the encoding module 4, and the drive control module 5 within the frame. The output module 1 and the third housing 500 are located on opposite sides.

[0044] In summary, the joint module 100 for humanoid robots of this invention, by providing a plurality of teeth 312 extending outward from the yoke 311 on the motor stator 31, and by independently designing the teeth 312 and the yoke 311 to provide flat conductors 313, allows the motor stator 31 to be arranged in a segmented manner, resulting in a higher slot fill factor compared to traditional stamped motor stators 31. Furthermore, the more regular cross-section of the flat conductors 313 allows for the embedding of more flat conductors 313 within the same slot volume, improving current carrying capacity and thus increasing torque density and peak output torque. Simultaneously, a higher slot fill factor means that the motor volume and weight can be reduced for the same power, which is crucial for the compactness of the robot joint.

[0045] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A joint module for a humanoid robot, characterized in that, include: An output module is used to connect to the humanoid robot; A deceleration module is connected to the output module; An external rotor motor includes a motor stator and a motor rotor disposed on the outer periphery of the motor stator. The motor rotor meshes with the side of the reduction module opposite to the output module and is rotatable relative to the motor stator. The motor stator includes a yoke and a plurality of teeth extending from the yoke in all directions. The teeth are independent of the yoke and are provided with flat conductors. A gap is formed between two adjacent teeth, and the flat conductors are at least partially located within the gaps. An encoding module engages with the side of the motor rotor opposite to the reduction module; The drive control module is connected to the motor stator and is located on the side of the encoding module relative to the motor rotor.

2. The joint module according to claim 1, characterized in that, The motor rotor includes a rotor housing and a drive shaft connected to the rotor housing. The motor stator has a through hole for the drive shaft to pass through. A drive gear is provided at the end of the drive shaft away from the rotor housing, and the drive gear meshes with the encoding module.

3. The joint module according to claim 2, characterized in that, The rotor housing has a plurality of magnets on the side facing the motor stator, and the magnets are arranged in an array around the outer periphery of the motor stator.

4. The joint module according to claim 3, characterized in that, All the magnets are rectangular and arranged in a Halbach array.

5. The joint module according to claim 2, characterized in that, The encoding module includes a first encoding gear and a second encoding gear, which mesh with the drive gear respectively. The first encoding gear and the second encoding gear are provided with induction magnetic rings, and the drive control module is provided with an encoder chip adapted to the induction magnetic rings.

6. The joint module according to claim 5, characterized in that, The drive gear is one of a PEK gear and an aluminum alloy gear, and the first and second coded gears are the other of the PEK gear and the aluminum alloy gear.

7. The joint module according to claim 1, characterized in that, Both the reduction module and the external rotor motor are provided with through holes, and the two through holes are interconnected to form a cavity. A hollow tube is provided in the cavity, and fixing members are provided on opposite sides of the hollow tube. The fixing members are used to fix the hollow tube to the reduction module and the external rotor motor, and the hollow tube is in a stationary state.

8. The joint module according to claim 7, characterized in that, The fixing component includes a first fixing component and a second fixing component. The first fixing component is used to fix the opposite sides of the hollow tube to the reduction module and the external rotor motor respectively. The second fixing component is located between the hollow tube and the reduction module and the external rotor motor, and is used to support the opposite sides of the hollow tube. The second fixing component and the hollow tube remain relatively stationary.

9. The joint module according to claim 1, characterized in that, The yoke is circular and has several grooves on its outer periphery, and the teeth are engaged in the grooves.

10. The joint module according to claim 9, characterized in that, The toothed portion has a retaining portion that is engaged within the groove, and the retaining portion is a trapezoidal structure that gradually expands outward toward the yoke portion.

Images