A machine hand integrally produced by 3D printing
The robotic hand produced by 3D printing uses TPU and support materials to simplify production, reduce costs, and improve flexibility and bionic characteristics. It solves the problems of structural complexity and inaccuracy in operation of traditional robotic dexterity hands, and expands the scope of applications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- PQ LABS INC
- Filing Date
- 2025-08-26
- Publication Date
- 2026-07-14
AI Technical Summary
Traditional robot dexterous hands have complex structures, high production costs, large assembly errors, require a lot of materials, are bulky, have high energy consumption, are complex to control, are difficult to simulate the soft touch of a human hand and are prone to injuring people, and are difficult to adapt to gentle operation scenarios.
Using TPU material combined with support material, a robotic hand is produced in one piece by 3D printing, including fingers, palm, back of hand and wrist. The drive motor unit is connected to the pull plate to achieve independent drive of five degrees of freedom, which simplifies the production process, reduces costs and improves the flexible bionic characteristics.
It reduces production costs and time, improves product consistency and stability, simulates the soft touch of human hands, adapts to diverse operational needs, and expands application scenarios, especially in the fields of medical care and service robots.
Smart Images
Figure CN224489169U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of robotic arm technology, specifically a robotic arm produced in one piece by 3D printing. Background Technology
[0002] The statements in this section are merely background information related to this utility model and do not necessarily constitute prior art.
[0003] In the field of robotics, the robot's dexterous hand, as an important actuator, plays a crucial role in enabling robots to perform diverse and precise operations.
[0004] Traditional robotic dexterous hands have complex structures, often requiring the separate processing of multiple components followed by tedious assembly steps. This not only leads to high production costs but also increases the likelihood of assembly errors due to the large number of parts, affecting the overall performance and stability of the dexterous hand. In terms of material selection, various types of materials are often needed to achieve the functions of different parts, further increasing material procurement costs and processing difficulty. Regarding the drive system, complex motors, linkages, gears, and other transmission mechanisms are frequently used to achieve finger movements. These transmission mechanisms occupy a significant amount of space, making it difficult to reduce the overall size of the dexterous hand and increasing energy loss and the probability of malfunctions. Furthermore, the coordinated operation of multiple transmission components places extremely high demands on the control system; even minor control deviations can lead to uncoordinated finger movements, affecting operational accuracy. Moreover, because the materials used are mostly rigid materials such as metals or hard plastics, it is difficult to simulate the soft touch and natural movements of a human hand, potentially causing injury during human contact and interaction, and making it unsuitable for scenarios requiring gentle manipulation.
[0005] Based on the above reasons, this utility model designs a robotic hand produced in one piece by 3D printing. By using TPU material as the main material of the robot hand and combining it with the supporting material, the robot hand can be molded in one piece by 3D printing technology, avoiding the shortcomings of traditional multi-part and multi-material manufacturing. While meeting the normal movement of the robot hand, it greatly improves the efficiency and quality of mass production of robot hands. Summary of the Invention
[0006] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a robotic hand produced in one piece by 3D printing. By using TPU material as the main material of the robotic hand and combining it with the supporting material, the robotic hand can be molded in one piece by 3D printing technology, avoiding the shortcomings of traditional multi-part and multi-material manufacturing. While meeting the normal movement of the robotic hand, it greatly improves the efficiency and quality of mass production of robotic hands.
[0007] To achieve the above objectives, this utility model provides a robotic hand produced by 3D printing in one piece, including an integrated hand made of TPU material. The integrated hand consists of fingers, palm, back of hand, and wrist. Pull tabs extending into the fingers are provided inside the palm. The pull tabs are connected to a drive motor assembly via traction wires. The drive motor assembly is mounted on a motor bracket inside the wrist. The front end of the pull tab is integrally printed with the fingertip of the finger. The palm, fingers, and back of hand have reserved top supports and pull tab supports for supporting 3D printing. The top supports and pull tab supports are in point contact with the palm and fingers. The top supports and pull tab supports are connected to the back of hand via grooves.
[0008] There are 6 drive motors, with 2 mounted horizontally in opposite directions inside the wrist.
[0009] Each drive motor assembly is individually connected to the pull tab corresponding to each finger via a traction line.
[0010] The pull tab is a sheet with a printing thickness of 1mm, and the width of the pull tab matches the width of the finger.
[0011] The palm, back of the hand, and fingers are provided with grooves, which are located at the positions corresponding to point contact.
[0012] The depth of the groove is the single-layer height set in the 3D printing.
[0013] The top support and pull tab support are made of PETG or PLA material.
[0014] The thickness of the finger joint is 0.8mm to 1mm.
[0015] The thickness of the knuckle portion of the finger is 2mm.
[0016] The back of the hand is 1.5mm thick, and there are longitudinal reinforcing ribs on the back of the hand, which are 3mm thick.
[0017] Compared with the prior art, the present invention has the following beneficial effects:
[0018] From a cost perspective, the 3D printing cost of the core structure of each robotic arm is only about 10 yuan, thanks to the integrated 3D printing design. This eliminates the traditional model of processing and assembling multiple parts separately, avoiding significant investment in parts manufacturing, transportation, and complex assembly processes. It greatly reduces costs in raw material procurement, production, and labor, making large-scale production economically feasible and facilitating the wider application and promotion of robotic dexterity hands.
[0019] In terms of manufacturing process, the integrated hand structure requires no assembly; it only requires disassembling the support structure and connecting it to the wrist drive structure. This feature greatly simplifies the production process. Compared to the cumbersome component assembly work in the traditional dexterity hand manufacturing process, it not only reduces production time and improves production efficiency, but also reduces the possibility of errors caused by manual assembly, improves product consistency and stability, and makes product quality easier to control.
[0020] In terms of performance, the flexible bionic characteristics are particularly outstanding. Utilizing relatively soft TPU material, it can simulate the hardness of a human hand, making the dexterous hand more in line with human usage habits during operation. When interacting with people, it provides a more natural and comfortable experience, reducing the risk of injury. For example, in a handshake, its soft material better conforms to the human hand, giving the other party a feeling closer to a real handshake. When grasping objects, especially fragile ones, the material's flexibility and adaptive adjustment to force enable gentle grasping, effectively preventing damage. This greatly expands the application scenarios of the dexterous hand, enabling it to play a vital role in fields with high requirements for flexible manipulation, such as medical care and service robots.
[0021] From a functional perspective, the five degrees of freedom and independently driven design endow the dexterous hand with a high degree of flexibility and precision. It can perform tasks such as picking up objects, grasping objects, shaking hands, tapping, and other programmable finger movements, adapting to various complex operational tasks. Whether it's delicate object grasping or interactive operations with humans, its flexible finger movements allow it to complete tasks with ease, greatly enhancing the robot's operational capabilities and adaptability, and meeting the diverse needs of different fields for dexterous robot operation. Attached Figure Description
[0022] Figure 1 This is a schematic cross-sectional view of the palm surface of this utility model.
[0023] Figure 2 This is a schematic diagram of the palm support structure of this utility model.
[0024] Figure 3 This is a schematic diagram of the palm surface of the present invention.
[0025] Figure 4 This is a schematic diagram of the back of the hand of this utility model.
[0026] Explanation of reference numerals in the attached figures
[0027] 1. Finger, 1-1 knuckle, 1-2 joint, 2. Pull tab, 3. Palm, 4. Wrist, 5. Drive motor assembly, 6. Motor bracket, 7. Top support, 8. Pull tab support, 9. Integrated hand, 10. Back of hand. Detailed Implementation
[0028] The present invention will now be further described with reference to the accompanying drawings.
[0029] See Figures 1-4 This invention provides a robotic hand produced by 3D printing, comprising an integrated hand 9 made of TPU material, which consists of fingers 1, palm 3, back of hand 10, and wrist 4. TPU material has moderate softness and hardness; by precisely controlling its thickness, it can match the strength requirements of different structural parts of the dexterous hand, which is the core of this invention's integrated 3D printing production. A pull tab 2 extending into the fingers 1 is provided inside the palm 3. The pull tab 2 is connected to a drive motor assembly 5 via a traction wire. The drive motor assembly 5 is mounted on a motor bracket 6 inside the wrist. The front end of the pull tab 2 is integrally printed with the fingertip of the fingers 1. The palm 3, fingers 1, and back of hand 10 have pre-reserved top supports 7 and pull tab supports 8 for supporting the 3D printing. The top supports 7 and pull tab supports 8 are in point contact with the palm 3 and fingers 1, and are connected to the back of hand 10 via grooves. The purpose of the point contact is to facilitate the removal of the support material. The top support 7 and the pull tab support 8 are in contact with the palm 3 and the fingers 1 at the top, and are connected at the bottom by a groove set on the back of the hand 10. They provide support in both the upper and lower directions, and further provide support through the interlayer adhesion between the support material and the materials of the palm, back of the hand and fingers.
[0030] There are 5 to 6 drive motors, with 2 mounted horizontally in opposite directions inside the wrist.
[0031] Each drive motor assembly 5 is individually connected to a pull tab 2 corresponding to each finger 1 via a traction line. The pull tab 2 is fixed inside the space between the fingers 1 and extends to the palm 3, connecting to the drive structure 5 on the wrist 4. By pulling the pull tab 2 towards the wrist 4 with the drive motor, the corresponding finger 1 is caused to curl, achieving a grasping action. When the motor releases the pull tab, the finger 1 automatically straightens due to the force of the finger joint and the restoring force of the pull tab 2, thus achieving independent drive of a single finger 1. This provides five degrees of freedom for the dexterous hand, enabling it to perform actions such as picking up objects, grasping objects, shaking hands, pressing, and other programmable finger movements. The design of the finger 1 mimics the slight bending of the knuckles towards the palm, so that when the fingertip of the finger 1 is pulled by the traction line via the pull tab integrally connected to it, the finger can bend and rebound like a human finger.
[0032] The pull tab 2 is a sheet with a printing thickness of 1mm. This balances the strength and elasticity of 3D printing, and also prevents significant twisting of the flexible connection between multiple knuckles during pulling operations. The width of the pull tab 2 matches the width of the finger 1; in this embodiment, the width of the pull tab is 8mm, which is slightly narrower than the finger 1.
[0033] The palm 3, back of the hand 10, and fingers 1 are provided with grooves printed with a depth equal to the single-layer height set by 3D printing. The purpose of the grooves is to provide more stable fixation for the support material, which is prone to displacement during the printing process when making point contact. This is because the support material is easily displaced during the printing process. By embedding the support material into the groove on the back of the hand 10 when printing the first layer of the internal support structure of the palm 3, the support material is provided with more stable fixation. This greatly improves the printing success rate and stability of point contact between different materials (TPU material and PETG or PLA material), ensuring the smooth progress of the entire printing process and the quality of the final product.
[0034] The top support 7 and the pull tab support 8 are made of PETG or PLA material. These two materials are inexpensive and have weak adhesion to TPU material, making the support material easier to remove.
[0035] The joint portion 1-2 of finger 1 needs to be bent, therefore the TPU material thickness of the joint portion 1-2 of finger 1 is 0.8mm to 1mm. This provides both low bending resistance and sufficient resilience, allowing the finger joint to bend flexibly. The knuckle portion 1-1 of finger 2 needs to be more rigid, therefore the TPU material thickness of the knuckle portion 1-1 of finger 1 is 2mm, thus providing a grip strength similar to that of finger bones.
[0036] The back of the hand requires longitudinal (finger direction) strength and lateral flexibility, so the TPU material used has a wall thickness of 1.5mm and longitudinal reinforcing ribs of 3mm, which effectively meets the special strength and flexibility requirements of the back of the hand.
[0037] The working principle of this utility model is as follows:
[0038] Using 3D printing technology, the entire hand structure is printed in one step using TPU material and support material (PETG or PLA) according to a pre-designed model. After printing, the top support 7 and pull tab support 8 inside the palm 3 are carefully removed, at which point the integrated hand structure is formed. Finally, the formed hand is connected to the wrist drive structure, and a complete robotic dexterous hand is assembled. The entire production process eliminates the need for complex secondary assembly of multiple hand parts, greatly shortening the production cycle, reducing labor costs, and minimizing product quality issues that may result from assembly errors.
[0039] The above are merely preferred embodiments of this utility model, intended only to aid in understanding the method and core concept of this application. The scope of protection of this utility model is not limited to the above embodiments; all technical solutions falling within the scope of this utility model's concept are protected. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should also be considered within the scope of protection of this utility model.
[0040] In the description of this utility model, it should be noted that the terms "upper", "lower", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0041] This invention comprehensively addresses the shortcomings of existing robotic dexterous hands in terms of production cost, manufacturing process, material usage, actuation method, and flexible bionic design, which limit their application and development in a wider range of fields. By using TPU material as the main material combined with supporting materials for integrated 3D printing, it avoids the traditional multi-part assembly mode, effectively reducing production costs. Modular assembly eliminates the need for excessive debugging, reducing production time and human error. The more flexible material and the varying thicknesses in different parts demonstrate the bionic advantages of flexible materials in mimicking finger functions, resulting in greater adaptability to different usage scenarios and a certain level of interactivity. Independent finger actuation allows for more complex operational tasks and provides more flexible and diverse options for refined simulation.
[0042] In addition, this invention allows for convenient and quick adjustments to the size, shape, and internal structure of the dexterous hand during the design phase, resulting in greater customizability. The integrated structure reduces the number of connection points between components, lowering the probability of malfunctions due to wear or loosening of connecting parts, and significantly reducing maintenance costs.
Claims
1. A robotic arm manufactured in one piece by 3D printing, characterized in that, The device includes an integrated hand (9) made of TPU material, which consists of fingers (1), palm (3), back of hand (10) and wrist (4). The palm (3) has a pull tab (2) extending into the fingers (1). The pull tab (2) is connected to a drive motor assembly (5) via a traction line. The drive motor assembly (5) is mounted on a motor bracket (6) in the wrist. The front end of the pull tab (2) is integrally printed with the fingertip of the finger (1). The palm (3), the fingers (1) and the back of hand (10) have reserved top supports (7) and pull tab supports (8) for supporting 3D printing. The top supports (7) and pull tab supports (8) are in point contact with the palm (3) and the fingers (1). The top supports (7) and pull tab supports (8) are connected to the back of hand (10) via grooves.
2. The robotic arm produced in one piece by 3D printing according to claim 1, characterized in that, The drive motor assembly (5) consists of 6 motors, with 2 motors installed horizontally in opposite directions inside the wrist.
3. The robotic arm produced in one piece by 3D printing according to claim 2, characterized in that, Each of the drive motor units (5) is individually connected to the pull tab (2) corresponding to each of the fingers (1) via a traction line.
4. The robotic arm produced in one piece by 3D printing according to claim 1, characterized in that, The pull tab (2) is a sheet with a printing thickness of 1 mm, and the width of the pull tab (2) matches the width of the finger (1).
5. The robotic arm produced in one piece by 3D printing according to claim 1, characterized in that, The palm (3), the back of the hand (10), and the fingers (1) are provided with grooves, which are located at the positions corresponding to the point contact.
6. The robotic arm produced in one piece by 3D printing according to claim 5, characterized in that, The depth of the groove is the single-layer height set by the 3D printing process.
7. The robotic arm produced in one piece by 3D printing according to claim 1, characterized in that, The top support (7) and the pull tab support (8) are supports made of PETG or PLA material.
8. The robotic arm produced in one piece by 3D printing according to claim 1, characterized in that, The thickness of the joint portion (1-2) of the finger (1) is 0.8 mm to 1 mm.
9. The robotic arm produced in one piece by 3D printing according to claim 1, characterized in that, The thickness of the knuckle portion (1-1) of the finger (1) is 2 mm.
10. The robotic arm produced in one piece by 3D printing according to claim 1, characterized in that, The back of the hand (10) has a thickness of 1.5 mm, and a longitudinal reinforcing rib is provided on the back of the hand (10), the thickness of which is 3 mm.