Modular jointed asymmetric three-fingered dexterous hand

Abstract

The utility model provides a kind of modular joint asymmetric three-fingered dexterous hand, it is related to robot technical field, including base and three fingers;Finger includes multiple modular joints and finger tip;Modular joint includes output end and connecting end;Output end can rotate;The output end rotation angle of each modular joint can be independently controlled;The connecting end of first section modular joint is detachably connected with base;In adjacent two modular joints, the connecting end of latter modular joint is detachably connected with the output end of former modular joint;Finger tip is detachably connected with the output end of modular joint in the end of finger.The utility model provides a kind of modular joint asymmetric three-fingered dexterous hand, solve the problem of difficult maintenance when three-fingered dexterous hand fails in prior art, can be convenient for the maintenance of three-fingered manipulator.

Description

Technical Field

[0001] This utility model relates to the field of robotics technology, specifically to a modular joint asymmetric three-finger dexterous hand. Background Technology

[0002] In the field of robotics, end effectors are the core components for robots to physically interact with their external environment. Three-fingered robotic arms are a type of end effector that, due to their balance of dexterity and structural simplicity, have become a common and preferred form of end effector.

[0003] However, early three-finger robotic hands mostly adopted a centrally symmetrical layout design. Although they could grasp the outer envelope of objects, because all the fingers had the same function and lacked specialization, they could not replicate the operation paradigm of the human hand thumb as the opposite side and the index / middle finger cooperating to pinch. They were extremely clumsy when performing complex tasks such as pinching, side pinching, and tool manipulation. Their flexibility and bionic operation capabilities were seriously insufficient, making it difficult to meet the needs of fine operations in unstructured environments.

[0004] To address the aforementioned shortcomings of symmetrically arranged three-finger robotic hands, an improved solution for a fully motor-driven three-finger dexterous hand has emerged in the prior art, such as the one described in patent number CN202423026414. This solution employs an asymmetrical structure with the thumb, index finger, and middle finger arranged perpendicularly, which improves grasping stability and operational flexibility to a certain extent. Furthermore, by directly driving joint movements with a motor, it eliminates the need for traditional mechanical transmission devices, simplifying the overall structure, reducing manufacturing costs, and thus solving the problem of poor dexterity in traditional dexterous hands to some extent.

[0005] However, the joints of the existing improved three-finger dexterous hand adopt a piecemeal splicing structure of motors, connectors, and gaskets. The joint components are directly connected by screws, forming an interdependent integrated assembly. This does not achieve independent modular design of the joints. When a single part such as a motor, connector, or gasket of a joint is damaged, the entire finger or even the palm must be disassembled because the components are tightly assembled and mutually restrictive. When reassembling after disassembly, the relative position of each joint, the connection gap, and the coaxiality of the rotating shaft need to be repeatedly calibrated and adjusted. At the same time, key parameters such as motor synchronization and force feedback threshold need to be rematched. Not only is the assembly process cumbersome and difficult to operate, but it is also very easy for insufficient assembly precision to lead to a decrease in the overall operating precision of the robot, which affects the promotion and application of the three-finger robot in real-world scenarios. Utility Model Content

[0006] To address the aforementioned technical problems, the modular joint asymmetric three-finger dexterous hand provided by this utility model facilitates the maintenance of three-finger robotic hands.

[0007] To achieve the above objectives, the technical solution adopted by this utility model is as follows: This utility model provides a modular joint asymmetrical three-finger dexterous hand, including a base and three fingers; each finger includes multiple modular joints and fingertips; each modular joint includes an output end and a connecting end; the output end is rotatable; the rotation angle of the output end of each modular joint can be independently controlled; the connecting end of the first modular joint is detachably connected to the base; in two adjacent modular joints, the connecting end of the latter modular joint is detachably connected to the output end of the former modular joint; each fingertips are detachably connected to the output end of the modular joint at the fingertips.

[0008] The modular joint asymmetric three-finger dexterous hand provided by this utility model preferably includes a housing, a control chip, a motor, and a planetary reducer; the control chip, the motor, and the planetary reducer are all fixed on the housing; the motor is drivenly connected to the planetary reducer; a driving bevel gear is provided on the output shaft of the planetary reducer; a driven bevel gear is provided on the housing and meshes with the driving bevel gear; the output end is the driven bevel gear; the connecting end is located on the housing; the connecting end on the subsequent housing is detachably connected to the output end on the previous housing; the motor is electrically connected to the control chip.

[0009] The modular joint asymmetric three-finger dexterous hand provided by this utility model preferably includes a main control board inside the base; a wireless signal transmission module inside the main control board; and a wireless signal transmission module inside the control chip.

[0010] The modular joint asymmetric three-finger dexterous hand provided by this utility model preferably has a plurality of visual sensors disposed on the base; the sensing direction of the visual sensors is toward the direction in which the fingers are positioned; the visual sensors are electrically connected to the main control board.

[0011] The modular joint asymmetric three-finger dexterous hand provided by this utility model preferably has a tactile sensor disposed inside the finger; the tactile sensor is electrically connected to the main control board.

[0012] The modular joint asymmetric three-finger dexterous hand provided by this utility model preferably has three bearing seats on the base; the bearing seats can output rotational force; the first segment of each finger of the modular joint can be rotatably fixed on the bearing seat; the bearing seats are electrically connected to the main control board.

[0013] The modular joint asymmetric three-finger dexterous hand provided by this utility model preferably has an embedded SOC integrated in the main control board.

[0014] The modular joint asymmetric three-finger dexterous hand provided by this utility model preferably includes an encoder; the output shaft of the planetary reducer is provided with a magnetic bead that can be recognized by the encoder; the encoder is electrically connected to the control chip.

[0015] The modular joint asymmetric three-finger dexterous hand provided by this utility model preferably comprises a thumb, an index finger, and a middle finger; the index finger includes two modular joints; the middle finger includes two modular joints; the thumb includes three modular joints; the output axis of the first modular joint of the thumb and the output axis of the second modular joint of the thumb are perpendicular to each other.

[0016] The modular joint asymmetric three-finger dexterous hand provided by this utility model preferably has an external rotor motor; the motor includes an external rotor and a stator; the rotor can rotate around the axis of the stator; the external rotor is fixed to the housing by four screws; the stator is fixed to the input end of the planetary reducer.

[0017] The above technical solution has the following advantages or beneficial effects: This invention provides a modular joint asymmetric three-finger dexterous hand, relating to the field of robotics, comprising a base and three fingers; each finger includes multiple modular joints and fingertips; each modular joint includes an output end and a connecting end; the output end is rotatable; the rotation angle of the output end of each modular joint can be independently controlled; the connecting end of the first modular joint is detachably connected to the base; in two adjacent modular joints, the connecting end of the latter modular joint is detachably connected to the output end of the former modular joint; each fingertips are detachably connected to the output end of the modular joint at the fingertips. The modular joint asymmetric three-finger dexterous hand provided by this invention solves the problem of difficult maintenance when three-finger dexterous hands malfunction in the prior art, facilitating the maintenance of three-finger robotic hands. Attached Figure Description

[0018] The present invention, its features, shape, and advantages will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings. Like reference numerals denote like parts throughout the drawings. The drawings are not intentionally drawn to scale; the focus is on illustrating the gist of the invention.

[0019] Figure 1 This is a schematic diagram of the overall structure of the modular joint asymmetric three-finger dexterous hand provided in Embodiment 1 of this utility model.

[0020] Figure 2This is a schematic diagram of the modular joint structure of the modular joint asymmetric three-finger dexterity hand provided in Embodiment 1 of this utility model.

[0021] Figure 3 This is a schematic diagram of the motor and planetary reducer of the modular joint asymmetric three-finger dexterous hand provided in Embodiment 1 of this utility model.

[0022] Figure 4 This is a schematic diagram of the circuit connection frame of the modular joint asymmetric three-finger dexterous hand provided in Embodiment 1 of this utility model. Detailed Implementation

[0023] Example 1: The modular joint asymmetric three-finger dexterous hand provided in Embodiment 1 of this utility model, such as Figures 1 to 4 As shown, it includes a base 1 and three fingers 2; each finger 2 includes multiple modular joints 21 and fingertips 22; each modular joint 21 includes an output end 211 and a connecting end 212; the output end 211 is rotatable; the rotation angle of the output end 211 of each modular joint 21 can be controlled independently; the connecting end 212 of the first modular joint 21 is detachably connected to the base 1; in two adjacent modular joints 21, the connecting end 212 of the latter modular joint 21 is detachably connected to the output end 211 of the former modular joint 21; the fingertips 22 are detachably connected to the output end 211 of the modular joint 21 at the end of the finger 2.

[0024] The modular joint asymmetrical three-finger dexterous hand provided in Embodiment 1 of this utility model uses a base 1 as the overall installation and support foundation. The first modular joint 21 of each finger 2 is detachably connected to the base 1 through its connecting end 212, completing the initial fixation of the finger 2. Since the output end 211 of each modular joint 21 has rotatable characteristics, and the rotation angle of the output end 211 of each modular joint 21 can be independently controlled, two adjacent modular joints 21 can be detachably connected to the output end 211 of the previous modular joint 21 through the connecting end 212 of the latter modular joint 21, which can be combined to form a finger 2 body with flexible and adjustable posture. Finally, the fingertip 22 is detachably connected to the output end 211 of the modular joint 21 at the end of the finger 2. The fingertip 22 moves in coordination with the independent rotation of the output end 211 of each modular joint 21, thereby realizing the grasping and pinching operation of the target object. Compared to existing three-finger dexterity hands where all fingers are controlled by a unified control center, requiring readjustment of the coordination between new joints and other joints, as well as the coordination between the new joints and the control center during each maintenance, this embodiment features a detachable structure design for the modular joint 21's connecting end 212 and base 1, connecting end 212 and output end 211, and finger 22 and output end 211. When any modular joint 21 or finger 22 malfunctions, it can be disassembled and replaced individually without disassembling the entire finger 2 or base 1, significantly reducing maintenance difficulty and cost.

[0025] The modular joint asymmetric three-finger dexterous hand provided in Embodiment 1 of this utility model solves the problem of difficult maintenance when a three-finger dexterous hand malfunctions in the prior art, and can facilitate the maintenance of the three-finger robotic hand.

[0026] To enable the modular joint 21 to be independently controlled and to independently drive the rotation of its connected structure, as a preferred embodiment, the modular joint 21 includes a housing 213, a control chip 214, a motor 215, and a planetary reducer 216. The control chip 214, motor 215, and planetary reducer 216 are all fixed on the housing 213. The motor 215 is connected to the planetary reducer 216 via a transmission. A driving bevel gear 2161 is provided on the output shaft of the planetary reducer 216. A driven bevel gear 2131 is provided on the housing 213 to mesh with the driving bevel gear 2161. The output end 211 is the driven bevel gear 2131. The connecting end 212 on the latter housing is detachably connected to the output end 211 on the former housing 213 (in this embodiment, it is preferred that a screw coaxially passes through the driven bevel gear 2131 and is fixed in the threaded hole of the connecting end 212 to achieve the connection). The motor 215 is electrically connected to the control chip 214. In this embodiment, the modular joint 21 uses the housing 213 as the integrated support base. The control chip 214, motor 215, and planetary reducer 216 are all fixed on the housing 213, forming an independent functional integrated unit. During operation, the control chip 214 sends a drive command to the motor 215. After the motor 215 starts, it outputs power and transmits it to the planetary reducer 216. The planetary reducer 216 reduces the speed of the motor 215 and increases the output torque. The torque is transmitted through the driving bevel gear 2161 on the output shaft of the planetary reducer 216 to the driven bevel gear 216 meshing on the housing 213. 131. The direction of power is reversed through the meshing transmission of bevel gears, ultimately driving the driven bevel gear 2131, which serves as the output end 211, to rotate. When two adjacent modular joints 21 are connected, a screw coaxially passes through the driven bevel gear 2131 at the output end 211 of the first housing 213 and is screwed to the threaded hole on the connecting end 212 of the second housing, thus achieving mechanical fixation and power transmission between the two modular joints 21. Furthermore, the control chip 214 precisely controls the motor 215, enabling independent rotation control of the output end 211 of each modular joint 21. The motor 215 directly drives the planetary reducer 216, and in conjunction with the meshing transmission of the driving bevel gear 2161 and the driven bevel gear 2131, it achieves power reduction and torque amplification, meeting the torque output required for grasping and operation. The bevel gear structure completes the power reversal, adapting to the multi-dimensional movement needs of the fingers.

[0027] In this embodiment, a main control board 11 is installed inside the base 1; a wireless signal transmission module is installed inside the main control board 11; and a wireless signal transmission module is installed inside the control chip 214. The wireless signal transmission module built into the main control board 11 and the wireless signal transmission module built into the control chip 214 of each modular joint 21 form a paired communication link. During operation, the main control board 11 generates control signals according to task requirements and wirelessly sends the instructions to the control chips 214 of each modular joint 21 through its own wireless signal transmission module. After receiving the instructions through its own wireless signal transmission module, the control chip 214 parses and converts them into drive signals to drive the motor 215 of the joint to run, thereby driving the output end 211 of the modular joint 21 to rotate. At the same time, the control chip 214 collects the rotation angle and motor load dynamics of the joint in real time and feeds back the status data to the main control board 11 through the wireless signal transmission module. The main control board 11 adjusts the control instructions according to the feedback data, thereby realizing the coordinated control of all modular joints 21. Wireless is only a preferred form in this embodiment. The main control board 11 can also control each modular joint 21 by connecting the main control board 11 and each control chip 214 through the connection control line.

[0028] In this embodiment, a plurality of visual sensors 12 are provided on the base 1; the sensing direction of the visual sensors 12 is towards the direction in which the finger 2 is positioned; the visual sensors 12 are electrically connected to the main control board 11. During operation, the visual sensors 12 collect image information (including the shape, size, and relative position of the object) of the target object around the finger 2 in real time, and transmit the collected image data to the main control board 11 in the base 1 in real time. After receiving the data, the main control board 11 analyzes and extracts features from the image information, and plans the rotation angle of the output end 211 of different modular joints 21 in combination with the real-time status feedback of each modular joint 21, so as to realize the planning of the movement trajectory of the finger 2. Then, it sends the appropriate action command to the control chip 214 of each modular joint 21, so that the finger 2 can match the shape of the target object and complete the grasping and pinching operation.

[0029] In this embodiment, a tactile sensor 2121 is provided inside the finger 22; the tactile sensor 2121 is electrically connected to the main control board 11. (In this embodiment, a control chip 214 is also provided inside the finger 22, and the control chip 214 is connected to a wireless signal transmission module. After the tactile sensor 2121 acquires information, it transmits it to the control chip 214, and finally transmits it to the main control board 11 through the wireless signal transmission module). When the finger 2 performs a grasping or pinching operation, at the moment the finger 22 contacts the target object, the tactile sensor 2121 will collect the contact pressure and pressure distribution during the contact process in real time, and transmit this tactile data to the main control board 11 in real time. After receiving the data, the main control board 11 combines the image information of the vision sensor 12 and the status feedback of each modular joint 21 to dynamically adjust the control commands of each modular joint 21 to prevent the object from slipping.

[0030] In this embodiment, three bearing seats 13 are provided on the base 1; the bearing seats 13 can output rotational force; the first modular joint 21 of each finger 2 is rotatably fixed on the bearing seat 13; the bearing seat 13 is electrically connected to the main control board 11. The three bearing seats 13 on the base 1 correspond one-to-one with the three fingers 2. The first modular joint 21 of each finger 2 is rotatably fixed on the corresponding bearing seat 13. The bearing seat 13 has a built-in drive component. By receiving the control command issued by the main control board 11 in the base 1, it drives itself to output rotational force. This rotational force directly drives the first modular joint 21 connected to it to rotate relative to the base 1, thereby adjusting the initial posture of the entire finger 2 and adjusting the opening angle of the finger 2 relative to the base 1. Subsequently, combined with the independent rotation control of each modular joint 21 on the finger 2, more postures of the finger 2 can be achieved.

[0031] To enable the main control board 11 to control each modular joint 21, in this embodiment, the main control board 11 integrates an embedded SOC. The embedded SOC is existing technology and can receive image data from the vision sensor 12, contact data from the tactile sensor 2121, and status feedback from each modular joint 21.

[0032] In this embodiment, the modular joint 21 also includes an encoder 217; a magnetic bead that can be identified by the encoder 217 is provided on the output shaft of the planetary reducer 216; the encoder 217 is electrically connected to the control chip 214. The encoder 217 is a position and speed detection component of the modular joint 21. By identifying the magnetic bead on the output shaft of the planetary reducer 216, the encoder 217 collects the motion state data of the joint output end in real time, providing feedback for the control chip 214. The encoder 217, the magnetic bead, and the method of use are existing technologies and will not be described in detail here.

[0033] In this embodiment, the three fingers 2 are the thumb 3, the index finger, and the middle finger; the index finger includes two modular joints 21; the middle finger includes two modular joints 21; the thumb includes three modular joints; the output shaft 31 of the first modular joint 21 of the thumb 3 and the output shaft 32 of the second modular joint are perpendicular to each other. The index and middle fingers are each equipped with two modular joints 21. Through the independent and coordinated rotation of the output ends 211 of the two modular joints 21, basic operational posture adjustments such as bending and extending of the fingers can be realized. The thumb 3 is equipped with three modular joints 21, which adds a motion node compared to the index and middle fingers. The output end rotation axis 31 of the first modular joint 21 of the thumb 3 is perpendicular to the axis of the output end rotation axis 32 of the second modular joint. When the first modular joint 21 rotates around the output end rotation axis 31, it can drive the thumb 3 to swing laterally. When the second modular joint rotates around the output end rotation axis 32 perpendicular to 31, it can realize the longitudinal bending of the thumb 3. Combined with the independent rotation of the third modular joint 21, it forms a three-dimensional movement and rotation. The three fingers 2 are controlled by the independent rotation of their respective modular joints 21. By using the three-dimensional movement of the thumb 3 in conjunction with the basic posture of the index and middle fingers, the operation of the thumb and index and middle fingers of the human hand is reproduced, thereby adapting to target objects of different shapes.

[0034] As a preferred embodiment, in this case, motor 215 is an external rotor motor; the motor includes an external rotor and a stator; the rotor can rotate about the axis of the stator; the external rotor is fixed to the housing by four screws; the stator is fixed to the input end of the planetary reducer 216. Figure 3 As shown in the figure, the four screws are fixed to the housing of the reducer and pass through the housing 213 to fix the outer rotor of the outer rotor motor 215. This embodiment uses an outer rotor motor because the rotor diameter of the outer rotor motor is larger than that of a conventional motor, and the radius of the magnetic field application point is longer. According to the principle of electromagnetism (torque is proportional to radius), it can generate greater torque under the same magnetic force, thereby improving power density. At the same time, since the outer rotor shell is directly exposed to the outside of the housing 213, the motor 215 has a better heat dissipation path, which helps to maintain efficiency during high-power operation.

[0035] In summary, this utility model provides a modular joint asymmetric three-finger dexterous hand, relating to the field of robotics technology, comprising a base and three fingers; each finger includes multiple modular joints and fingertips; each modular joint includes an output end and a connecting end; the output end is rotatable; the rotation angle of the output end of each modular joint can be independently controlled; the connecting end of the first modular joint is detachably connected to the base; in two adjacent modular joints, the connecting end of the latter modular joint is detachably connected to the output end of the former modular joint; each fingertips are detachably connected to the output end of the modular joint at the fingertips. The modular joint asymmetric three-finger dexterous hand provided by this utility model solves the problem of difficult maintenance when three-finger dexterous hands malfunction in the prior art, facilitating the maintenance of three-finger robotic hands.

[0036] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the contents of the present utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present utility model.

Claims

1. A modular joint asymmetric three-finger dexterous hand, characterized in that, Includes a base and three fingers; The finger comprises multiple modular joints and fingertips; The modular joint includes an output end and a connecting end; the output end is rotatable; the rotation angle of the output end of each modular joint can be controlled independently. The connecting end of the modular joint described in the first section is detachably connected to the base; in two adjacent modular joints, the connecting end of the latter modular joint is detachably connected to the output end of the former modular joint. The finger is detachably connected to the output end of the modular joint at the end of the finger.

2. The modular joint asymmetric three-finger dexterous hand as described in claim 1, characterized in that, The modular joint includes a housing, a control chip, a motor, and a planetary reducer; The control chip, the motor, and the planetary reducer are all fixed to the housing; The motor is connected to the planetary reducer; a driving bevel gear is provided on the output shaft of the planetary reducer; a driven bevel gear is provided on the housing and meshes with the driving bevel gear; The output end is the driven bevel gear; The connection end is located on the housing; the connection end on the subsequent housing is detachably connected to the output end on the preceding housing; The motor is electrically connected to the control chip.

3. The modular joint asymmetric three-finger dexterous hand as described in claim 2, characterized in that, The base contains a main control board; the main control board contains a wireless signal transmission module; the control chip contains a wireless signal transmission module.

4. The modular joint asymmetric three-finger dexterous hand as described in claim 3, characterized in that, The base is provided with a plurality of visual sensors; the sensing direction of the visual sensors is toward the direction in which the finger is positioned. The vision sensor is electrically connected to the main control board.

5. The modular joint asymmetric three-finger dexterous hand as described in claim 3, characterized in that, A tactile sensor is installed inside the finger; the tactile sensor is electrically connected to the main control board.

6. The modular joint asymmetric three-finger dexterous hand as described in claim 3, characterized in that, The base is provided with three bearing seats; the bearing seats can output rotational force; The modular joint of the first segment of each finger is rotatably fixed to the bearing seat; The bearing housing is electrically connected to the main control board.

7. The modular joint asymmetric three-finger dexterous hand as described in claim 3, characterized in that, The main control board integrates an embedded SOC.

8. The modular joint asymmetric three-finger dexterous hand as described in claim 2, characterized in that, The modular joint also includes an encoder; the output shaft of the planetary reducer is provided with a magnetic bead that can be recognized by the encoder; The encoder is electrically connected to the control chip.

9. The modular joint asymmetric three-finger dexterous hand as described in claim 1, characterized in that, The three fingers mentioned are the thumb, index finger, and middle finger; The index finger includes two of the modular joints; the middle finger includes two of the modular joints; The thumb includes three modular joints; the output shafts of the first modular joint of the thumb and the output shafts of the second modular joint of the thumb are perpendicular to each other.

10. The modular joint asymmetric three-finger dexterous hand as described in claim 2, characterized in that, The motor is an external rotor motor; the motor includes an external rotor and a stator; The rotor can rotate about the axis of the stator; The outer rotor is fixed to the housing by four screws; the stator is fixed to the input end of the planetary reducer.

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