External mechanical arm joint stabilizer and control method thereof

Abstract

The application discloses an external mechanical arm joint stabilizer and a control method thereof. The stabilizer comprises suction components and suctioned components arranged at a first mechanical arm joint and a second mechanical arm joint capable of cooperating with each other, wherein the suction components and the suctioned components are oppositely arranged and capable of realizing stable positioning of the first mechanical arm joint and the second mechanical arm joint by suctioning the suctioned components through the suction components after the first mechanical arm joint and the second mechanical arm joint are positioned at predetermined positions. The stabilizer has the advantages that the stability of the mechanical arm joint is effectively improved, the installation and maintenance are more convenient, the product cost and the maintenance complexity are effectively reduced, the stability is realized through external physical structures, the system complexity and the cost are reduced, the installation and maintenance are easy, the reliability and the efficiency of the mechanical arm in high-precision operation are significantly increased, and the stabilizer is suitable for precision operation application.

Description

Technical Field

[0001] This invention relates to a component structure of a robotic arm in industrial and medical robots, and more particularly to an external robotic arm joint stabilizer and its control method for industrial and medical robotic arms, belonging to the fields of industrial automation and medical robotics technology. Background Technology

[0002] With the rapid development and technological breakthroughs in artificial intelligence, robotic arms are increasingly widely used in modern industrial automation and the medical field. Especially in the medical field, robotic arms have become an important component of medical automation. The stability of robotic arm joints is crucial to ensuring the precise and safe execution of tasks, particularly in applications requiring highly precise control, such as medical surgical robots or precision manufacturing. Therefore, robotic arms in industrial and medical robots need high pose stability to provide a safer and more efficient operating environment for both industries. Specifically, in industrial settings, robotic arms are commonly used for assembly, handling, and welding. They need to maintain high stability in specific poses to support precise operations. For example, spot welding robots in the automotive industry rely on precise joint control to achieve high-speed, high-precision operations. In medical settings, especially in surgical robot applications, the development of surgical robots depends on extremely precise joint motion control. This requires robotic arm joints to remain stable when subjected to reaction forces, especially when in direct contact with the human body. Therefore, the stability of robotic arm joints is crucial to ensuring the safety and precision of surgery.

[0003] However, traditional robotic arm designs often emphasize rigid structures, which poses challenges to improving the compliance and safety of robotic arms in dynamic and complex environments. While existing technologies incorporate built-in braking systems to achieve stability, such as motors, reducers, brake pads, and braking devices, these systems often result in bulky and complex robotic arms due to space constraints. This makes designing conventional braking and holding mechanisms difficult, leading to insufficient rigidity and difficulty in achieving truly stable braking and holding. Furthermore, improving stability often requires replacing the robotic arm with a more complex or powerful one, significantly increasing costs. In addition, the maintenance and replacement of these systems are quite cumbersome. For example, friction-type brake holders and holding brakes often fail to maintain their intended positions due to space limitations and insufficient rigidity, potentially causing errors, shutdowns, or damage. While existing high-load robotic arms can partially solve these problems, their high cost and large size limit their effectiveness in specific applications.

[0004] A typical example is the Chinese invention patent application with publication number CN107290956A, entitled "A Position Control Method for a Single-Joint Flexible Robotic Arm Based on State Feedback." The published text shows that by employing a built-in mechanical structure (motor, reducer, torsion spring) combined with a sophisticated control algorithm, it significantly improves joint stability and enhances the robot's compliance and safe physical interaction capabilities in dynamic environments. While effective, this method primarily relies on complex control algorithms to improve the robotic arm's response speed, stability, and static accuracy. In contrast, the invention with authorization publication number CN107483781B, entitled "A Self-Leveling Stabilizing Device," has very high requirements for structural compactness, high sensitivity, and a complex sensor system, making it difficult to operate and maintain. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide an external robotic arm joint stabilizer and its control method that has a compact structure, good rigidity, and thus can effectively improve the stability of robotic arm joints and has low manufacturing cost.

[0006] To solve the above-mentioned technical problems, the external robotic arm joint stabilizer of the present invention includes an attraction component and a attracted component respectively disposed at two robotic arm joints, namely a first robotic arm joint and a second robotic arm joint, which can cooperate with each other. The attraction component and the attracted component are disposed opposite to each other and can achieve stable positioning of the first robotic arm joint and the second robotic arm joint by attracting the attracted component after the first robotic arm joint and the second robotic arm joint are in a predetermined position.

[0007] The attraction component includes a first clamp device mounted on the first robotic arm joint and an electromagnetic mechanism mounted on the first clamp device capable of attraction. The attraction component includes a second clamp device mounted on the second robotic arm joint and an adsorption surface disposed on the second clamp device and opposite to the electromagnetic mechanism. The electromagnetic mechanism can adsorb onto the adsorption surface in the activated state to achieve stable positioning of the first and second robotic arm joints.

[0008] The No. 1 clamp device includes two No. 1 semi-circular clamps and a No. 1 connecting ear plate provided on each of the No. 1 semi-circular clamps. The two No. 1 semi-circular clamps are clamped onto the No. 1 mechanical joint and then connected and fixed by the No. 1 connecting ear plate.

[0009] The electromagnetic mechanism includes an electromagnet assembly and an elastic tension member that cooperates with the electromagnet assembly. The first clamp device is provided with a mounting cavity, and the electromagnet assembly and the elastic tension member are mounted in the mounting cavity.

[0010] The electromagnet assembly is equipped with a guide rod that extends out of the mounting cavity.

[0011] A connecting column is provided inside the mounting cavity, and the elastic tension member is a tension spring connecting the connecting column and the electromagnet assembly.

[0012] The second clamp device includes two second semi-circular clamps and a second connecting ear plate provided on each of the second semi-circular clamps. Each of the two second semi-circular clamps is provided with a semi-annular groove on the opposite side of the electromagnetic mechanism. Each of the two semi-annular grooves is provided with adsorption material for forming a semi-circular adsorption surface after the two second semi-circular clamps are installed together.

[0013] The adsorbent material is a silicon steel sheet with a textured surface.

[0014] The electromagnetic mechanism controls the operation of the electromagnet assembly through a control unit.

[0015] The electromagnetic mechanism is also controlled via a wireless communication unit that communicates wirelessly with the control unit.

[0016] The wireless communication unit consists of a battery compartment with a built-in battery, a circuit controller for providing control signals to the electromagnet assembly, a wireless transceiver capable of transmitting wireless signals, and a battery for providing power to the circuit controller and the wireless transceiver. The wireless transceiver is connected to the circuit controller and can be used to remotely wirelessly control the electromagnet assembly.

[0017] A control method using the above-mentioned external robotic arm joint stabilizer includes the following steps: A. The sensors of the robotic arm control system detect the posture angles of the first and second robotic arm joints when they reach the predetermined positions. B. When the sensors in the robotic arm control system detect that the first and second robotic arm joints are subjected to external forces, the electromagnetic mechanism of the attraction component is activated through the control unit. C. The electromagnetic force generated by the electromagnet assembly in the electromagnetic mechanism is used to attract the adsorption surface of the attracted component, resisting external forces and maintaining the joint position and posture.

[0018] The advantages of this invention are: (1) The joint stability is mainly achieved by external auxiliary stabilizing mechanism, without relying on complex built-in components and control algorithms. It can provide effective adsorption force without affecting the dynamic range of the robotic arm, thereby effectively improving the stability of the robotic arm joint. Moreover, the external structure is easier to install and maintain, thus effectively reducing product cost and maintenance complexity. This ingenious idea of ​​achieving joint stability directly through external structure does not rely on complex built-in mechanical structure or control algorithm, but achieves stability through external physical structure, reducing system complexity and cost, making it easy to install and maintain, and significantly increasing the reliability and efficiency of the robotic arm in high-precision operation, making it suitable for precision operation applications.

[0019] (2) By using a textured silicon steel sheet as an adsorption material for adsorption with the electromagnetic mechanism, reliable adsorption of the two robotic arm joints is achieved, further improving the stable positioning effect.

[0020] (3) The reasonable structural design of the electromagnetic mechanism in the attraction component uses elastic tension components to realize the electromagnet’s energization and de-energization return. In particular, the guide rod is used for guidance during the operation, which makes the operation reliable and the operation stable, further improving the stability and accuracy of use.

[0021] (4) The system’s flexibility is increased by the wireless communication unit that works with the control unit. That is, the electromagnetic mechanism can be remotely wirelessly controlled by the built-in battery, wireless transceiver and related circuit controller. When the robotic arm needs to be kept stable in a specific position, such as in surgery, massage, physiotherapy or rehabilitation, the wireless control allows the operator to activate the stabilizer at a safe distance, or to activate it automatically when the control system receives the corresponding sensor signal, thereby ensuring the accuracy and safety of the surgery and treatment process.

[0022] (5) Combining wired and wireless control modes, it is not only suitable for industrial applications that require high-precision operation, but also meets the application needs of surgical robots, massage robots, physiotherapy robots and rehabilitation robots in the field of healthcare. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall principle structure of the external robotic arm joint stabilizer of the present invention; Figure 2 This is a schematic diagram of the installation state structure of the suction component and the suction-bearing component in this invention; Figure 3 This is a schematic diagram of the cooperative use state of the suction component and the suction-bearing component in this invention; Figure 4 This is an exploded structural diagram of the suction component in this invention; Figure 5 This is an exploded structural diagram of the attracted component in this invention; Figure 6 This is a partially enlarged three-dimensional structural diagram of the suction component and the suction-bearing component in this invention; Figure 7 This is a partially enlarged front view schematic diagram of the attraction component and the attracted component in this invention. Detailed Implementation

[0024] The external robotic arm joint stabilizer and its control method of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] The external robotic arm joint stabilizer of the present invention is suitable for both industrial and medical applications, especially for robotic arms that require high joint stability, such as those used in medical, industrial, surgical, massage, physiotherapy or rehabilitation applications that require high-precision operation. In other words, it is suitable for applications that require high precision and high safety, such as medical surgical robots, massage robots, physiotherapy robots, etc. It includes a suction component 3 set at the first robotic arm joint 1 and a suction-bearing component 4 set at the second robotic arm joint 2. Through the mutual cooperation of the first robotic arm joint 1 and the second robotic arm joint 2, a predetermined posture angle can be reached. The suction component 3 and the suction-bearing component 4 are opposite each other and can perform suction action. The aforementioned suction assembly 3 includes a first clamp device 5 mounted on the first robotic arm joint and an electromagnetic mechanism 6 mounted on the first clamp device. As shown in the figure, in this embodiment, the first clamp device 5 includes two first semi-circular clamps 9 and a first connecting ear plate 10 provided on each first semi-circular clamp. The two first semi-circular clamps 9 are clamped onto the first robotic arm joint 1 and then connected and fixed by the first connecting ear plates. The electromagnetic mechanism 6 includes an electromagnet assembly 11 and an elastic tension member 12 that cooperates with the electromagnet assembly. The first clamp device 5 is provided with a mounting cavity 13, which is used to... Figure 7 As can be seen, the mounting cavity 13 is formed by the barrel-shaped inner cavity of the seat body protruding from the outer circumferential surface of the No. 1 clamp device, with the left end of the seat body closed and the right end open. Figure 7 (as shown in the direction), that is: the side facing the attracted component 4 is the open end, the electromagnet assembly of the electromagnetic mechanism 6 is a barrel-shaped structure and is placed in the placement cavity, the attracted component 4 includes the second clamp device 7 installed on the second mechanical arm joint and the adsorption surface 8 provided on the end face of the second clamp device, the electromagnet assembly 11 extends out of the placement cavity and is attracted to the adsorption surface 8 of the attracted component 4 by overcoming the force of the elastic tension member 12 in the activated state, or retracts into the placement cavity by the force of the elastic tension member 12 in the inactive state; Depend on Figure 5As can be seen, the so-called No. 2 clamp device 7 includes two No. 2 semi-circular clamps 16 and a No. 2 connecting ear plate 17 provided on each No. 2 semi-circular clamp. Since the electromagnet 11 needs to be attracted to the adsorption surface 8, the opening of the mounting cavity corresponds to the position of the adsorption surface 8, and the side end faces of the two No. 2 semi-circular clamps ( Figure 7 The left and right end faces shown are defined as side end faces, that is, the left end face in this embodiment. Both of them are provided with semi-annular grooves 18. After the two semi-annular grooves 12 are joined together, they can form a complete annular groove. Thus, semi-circular adsorption material 19 is placed in both semi-annular grooves to form the adsorption surface mentioned above. During installation, the attraction component 3 and the attracted component 4 are tightly fixed to the opposite rotational sides of the first robotic arm joint 1 and the second robotic arm joint 2 by the first semi-circular clamp 9 and the second semi-circular clamp 16, respectively. This design not only ensures the ease of installation but also ensures that the normal movement of the robotic arm joints will not be interfered with when not inactive. In use, after the first robotic arm joint 1 and the second robotic arm joint 2 are in the predetermined position, the electromagnetic mechanism 6 can be activated by energizing it, thereby enabling the electromagnet assembly of the electromagnetic mechanism to overcome the tension of the elastic tension member 12 and attract to the attraction surface 8. Thus, by directly setting the attraction component and the attracted component on the two robotic arm joints that cooperate with each other (i.e., the direct interaction between the electromagnetic mechanism externally placed on the robotic arm joint and the textured surface), an external auxiliary stabilizing mechanism is formed. After the two robotic arm joints are in the predetermined position, the electromagnet assembly of the electromagnetic mechanism can be energized to achieve stable positioning of the two robotic arm joints. The design of this invention is specifically developed for various robotic arms suitable for surgical, massage, physiotherapy, rehabilitation, and industrial applications. Its modular construction makes it easy to install and maintain on existing robotic arms.

[0026] Furthermore, the electromagnet 11 is equipped with a guide rod 14 extending out of the mounting cavity. Specifically, a guide hole is provided on the closed end of the base, and the guide rod 14 extends into the guide hole, thereby preventing the electromagnet 11 from rotating within the mounting hole and improving the reliability of use. In addition, to further increase the reliability of installation, the inner surfaces of the first semi-circular clamp 9 and the second semi-circular clamp 16 are both concave and convex, thereby improving the reliability of installation and fixation with the first robotic arm joint 1 and the second robotic arm joint 2.

[0027] Furthermore, a connecting post 15 is provided on the closed left end of the seat, located within the mounting cavity 13. A tension post is provided on the end face of the electromagnet assembly 11. The elastic tension member 12 is a tension spring connecting the connecting post 15 and the tension post of the electromagnet assembly 11. The adsorption material 19 is a textured silicon steel sheet. Of course, the adsorption material can also be partially or entirely made of a metal material with magnetic properties to provide a stronger adsorption force. Thus, in the inactive state, the electromagnet assembly 11 is tightened by the tension spring to prevent contact with the attracted component 4, thereby avoiding affecting the normal movement of the joint. When the electromagnet assembly of the attraction component 3 is activated, it is tightly attracted to the attraction component 4 to enhance the stability of the joint.

[0028] Furthermore, regarding the control part of the electromagnetic mechanism 6, the electromagnetic mechanism 6 controls the electromagnet assembly to move through the control unit 20. The control unit 20 communicates with the robotic arm control system, which mainly includes a host computer / microcontroller 24 and a robotic arm control cabinet 25. When the control unit receives an activation signal, the electromagnetic mechanism of the attraction component 3 is activated and contacts the textured surface of the steel of the attraction component 4, providing stable support. When it is necessary to release or adjust the position of the robotic arm, under the control of the control unit and the action of the spring, the electromagnetic unit of the attraction component 3 retracts, releasing the contact with the attraction component 4 and allowing the joint to return to a free-moving state.

[0029] In addition, to achieve diverse control capabilities, the electromagnetic mechanism 6 can also be controlled via a wireless communication unit that communicates wirelessly with the control unit. This allows for both wired and wireless control modes, ensuring operational flexibility and convenience.

[0030] In this embodiment, the specific wireless communication unit is as follows: Figure 3 As shown, it consists of a battery compartment 21 with a built-in battery, a circuit controller 22 for providing control signals to the electromagnet assembly, a wireless transceiver 23 capable of transmitting wireless signals, and a battery for providing power to the circuit controller 22 and the wireless transceiver 23. The wireless transceiver 23 is connected to the circuit controller 22 and can remotely wirelessly control the electromagnet assembly through the cooperation of the wireless transceiver and the circuit controller.

[0031] (1) Wired control mode In wired control mode, the control unit 20 is connected to the attraction assembly 3 via a data cable. This mode allows for precise transmission of control signals and ensures stable power supply to the electromagnetic mechanism. The barrel-shaped electromagnet assembly of the attraction assembly 3 can be activated when a stable signal is received, attracting the textured surface of the steel in the attraction assembly 4 to achieve instantaneous joint stabilization. This wired connection ensures the immediacy and reliability of control, making it particularly suitable for medical and industrial applications with complex operating environments or extremely high requirements for immediacy.

[0032] (2) Wireless control mode This mode increases the system's flexibility by enabling remote wireless control of the electromagnetic mechanism through a built-in battery (not shown in the diagram), wireless transceiver, and related circuit controllers. When the robotic arm needs to maintain stability in a specific position, such as in surgery, massage, physiotherapy, or rehabilitation applications, wireless control allows the operator to activate the stabilizer from a safe distance or automatically activate it when the control system receives a corresponding sensor signal, thereby ensuring the accuracy and safety of the surgical and treatment process. Combining wired and wireless control modes, this invention is not only suitable for industrial applications requiring high-precision operation, but also meets the application needs of surgical robots, massage robots, physiotherapy robots, and rehabilitation robots in the healthcare field. Through external control, this invention greatly improves the adaptability and ease of operation of the robotic arm, providing a new solution for robotic arm joint stabilization technology. Example

[0033] The robotic arm joint stabilization control method using the above-described robotic arm joint stabilizer in this embodiment includes the following steps: A. The sensor (not shown in the figure) of the robotic arm control system detects the posture angle of the first robotic arm joint 1 and the second robotic arm joint 2 when they reach the predetermined position. B. When the sensors of the robotic arm control system detect that the first robotic arm joint 1 and the second robotic arm joint 2 are subjected to external forces, the electromagnetic mechanism of the attraction component 3 is activated by the control unit 20. C. The electromagnetic force generated by the electromagnet assembly in the electromagnetic mechanism is used to attract the adsorption surface of the attracted component 4, resisting external forces and maintaining the joint position and posture.

[0034] This control method allows the mechanism to remain inactive when no activation signal is received, held within the barrel-shaped cavity by a tension spring. When needed, the control unit sends a signal to activate the internal columnar electromagnet assembly, generating electromagnetic attraction that draws the electromagnet to the attracted component 4, thus providing additional stability at the robotic arm joint. This direct physical interaction not only simplifies the structure but also reduces reliance on complex control algorithms and built-in mechanical components, demonstrating the innovation and practicality of this invention.

[0035] In addition, based on the above-mentioned wired and wireless control modes, the wired mode connects to the robotic arm control system via a data cable to ensure stable signal transmission, while the wireless mode utilizes a built-in battery and wireless transceiver to provide greater flexibility and convenience for operation and supports remote control.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. An external robotic arm joint stabilizer, characterized in that: It includes a suction component (3) and a suction-attached component (4) respectively set at the first robotic arm joint (1) and the second robotic arm joint (2) that can cooperate with each other. The suction component (3) and the suction-attached component (4) are arranged opposite to each other and can achieve stable positioning of the first robotic arm joint (1) and the second robotic arm joint (2) by suctioning the suction-attached component after the first robotic arm joint (1) and the second robotic arm joint (2) are in a predetermined position. The suction assembly (3) includes a first clamp device (5) installed on the first robotic arm joint and an electromagnetic mechanism (6) installed on the first clamp device that can perform suction action. The suction assembly (4) includes a second clamp device (7) installed on the second robotic arm joint and an adsorption surface (8) set on the second clamp device and located opposite to the electromagnetic mechanism (6). The electromagnetic mechanism (6) can adsorb with the adsorption surface (8) in the activated state to achieve stable positioning of the first robotic arm joint (1) and the second robotic arm joint (2). The electromagnetic mechanism (6) includes an electromagnet assembly (11) and an elastic tension member (12) that cooperates with the electromagnet assembly. The first clamp device (5) is provided with a mounting cavity (13), and the electromagnet assembly (11) and the elastic tension member (12) are mounted in the mounting cavity. The second clamp device (7) includes two second semi-circular clamps (16) and a second connecting ear plate (17) provided on each of the second semi-circular clamps. Both of the second semi-circular clamps are provided with a semi-annular groove (18) on the opposite side of the electromagnetic mechanism. Both of the semi-annular grooves (18) are provided with adsorption material (19) for forming the adsorption surface after the two second semi-circular clamps are installed together.

2. The external robotic arm joint stabilizer according to claim 1, characterized in that: The first clamp device (5) includes two first semi-circular clamps (9) and a first connecting ear plate (10) provided on each first semi-circular clamp. The two first semi-circular clamps (9) are clamped on the first robotic arm joint and then connected and fixed by the first connecting ear plate.

3. The external robotic arm joint stabilizer according to claim 1 or 2, characterized in that: The electromagnet assembly (11) is equipped with a guide rod (14) that extends out of the mounting cavity.

4. The external robotic arm joint stabilizer according to claim 3, characterized in that: The mounting cavity (13) is provided with a connecting column (15), and the elastic tension member (12) is a tension spring connected between the connecting column (15) and the electromagnet assembly (11).

5. The external robotic arm joint stabilizer according to claim 1, 2 or 4, characterized in that: The adsorbent material (19) is a silicon steel sheet with a textured surface.

6. The external robotic arm joint stabilizer according to claim 5, characterized in that: The electromagnetic mechanism (6) controls the operation of the electromagnet assembly through the control unit (20).

7. The external robotic arm joint stabilizer according to claim 6, characterized in that: The electromagnetic mechanism (6) is also controlled by a wireless communication unit that communicates wirelessly with the control unit.

8. The external robotic arm joint stabilizer according to claim 7, characterized in that: The wireless communication unit consists of a battery compartment (21) with a built-in battery, a circuit controller (22) for providing control signals to the electromagnet assembly, a wireless transceiver (23) capable of transmitting wireless signals, and a battery for providing power to the circuit controller (22) and the wireless transceiver (23). The wireless transceiver (23) is connected to the circuit controller (22) and can remotely wirelessly control the electromagnet assembly through the cooperation of the wireless transceiver and the circuit controller.

9. A control method employing an external robotic arm joint stabilizer as described in any one of claims 6-8, characterized in that, Includes the following steps: A. The sensors of the robotic arm control system detect the posture angles of the first robotic arm joint (1) and the second robotic arm joint (2) when they reach the predetermined positions. B. When the sensors of the robotic arm control system detect that the first robotic arm joint (1) and the second robotic arm joint (2) are subjected to external forces, the electromagnetic mechanism of the attraction component (3) is activated by the control unit (20). C. The electromagnetic force generated by the electromagnet assembly in the electromagnetic mechanism is used to attract the adsorption surface of the attracted component (4) to resist external forces and maintain the joint position and posture.

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