Clamping jaw device, clamping jaw control method and robot

Abstract

The invention relates to the technical field of robots, and discloses a clamping jaw device, a clamping jaw control method and a robot. The clamping jaw device comprises a base body, a driving module, a control module and a driving module. The at least two clamping jaw modules are movably arranged on the base body, and each clamping jaw module has a parallel clamping mode and an envelope clamping mode which can be switched; a motor is arranged in the driving module, and the driving module is arranged on the base body, is in driving connection with the at least two clamping jaw modules and is used for driving the at least two clamping jaw modules to synchronously execute a parallel clamping mode or an enveloping clamping mode; the control module is in communication connection with the motor and has a switchable position control mode and a torque control mode; according to the clamping jaw device, based on a current feedback control mechanism, accurate control over clamping force is achieved, expansibility is good, meanwhile, the structure and control logic are simplified, hardware cost is reduced, system reliability is higher, and safety can be guaranteed when precise objects or vulnerable objects are grabbed.

Description

Technical Field

[0001] This application belongs to the field of robotics technology, specifically relating to a gripper device, a gripper control method, and a robot. Background Technology

[0002] With the rapid development of intelligent manufacturing, service robots, and special operations, robotic arms, as core components for performing grasping and manipulation tasks, face higher demands on their operational flexibility, environmental adaptability, and gripping stability. Traditional rigid grippers often suffer from poor gripping stability and insufficient adaptability when dealing with objects that are complex in shape, diverse in material, or fragile. While flexible robotic arms have a certain degree of compliance, they still fall short in terms of force control precision and structural controllability.

[0003] To address this, existing technologies have developed a solution that combines both approaches, namely, sequentially incorporating rigid and flexible segments along the depth direction of the gripper. The flexible segment primarily relies on the elastic deformation of the material to generate a passive envelope. To ensure gripping stability, existing structures also incorporate fingertip force sensors or joint lateral force sensors to detect the contact force on the gripped object. This necessitates additional communication interfaces, leading to a more complex mechanical structure for the gripper itself, increased complexity in the control logic, higher costs, and poor scalability. Summary of the Invention

[0004] The purpose of this application is to provide a gripper device, gripper control method, and robot to solve the problem that existing grippers detect the contact force of the gripped object by setting up fingertip force sensors or joint side force sensors, which leads to complex structure and control logic, increased cost, and poor scalability.

[0005] To achieve the above objectives, the first aspect of this application provides a gripper device, comprising: Matrix; At least two gripper modules are movably mounted on the base, and the gripper modules have switchable parallel gripping mode and envelope gripping mode; A drive module with a built-in motor is disposed on the base and drives and connects at least two gripper modules respectively, for driving at least two gripper modules to synchronously execute the parallel gripping mode or the envelope gripping mode. The control module is communicatively connected to the motor and has switchable position control mode and torque control mode; Specifically, when executing the parallel clamping mode, the control module is configured to acquire the operating current of the motor, and if the operating current reaches a first operating threshold within a first preset time, switch the position control mode to the torque control mode and control the operating current of the motor to remain within the first safety threshold; when executing the envelope clamping mode, the control module is configured to acquire the operating current of the motor, and if the operating current reaches a second operating threshold within a second preset time, switch the position control mode to the torque control mode and control the operating current of the motor to remain within the second safety threshold.

[0006] As a further improvement to the above technical solution: In some embodiments, the drive module includes The joint module has the motor built-in. A mechanical transmission module, wherein the input side of the mechanical transmission module is driven to be connected to the output end of the joint module, and the output side of the mechanical transmission module is driven to be connected to the gripper module.

[0007] In some embodiments, the mechanical transmission module includes: A transmission flange is connected to the output end of the joint module. A drive shaft is rotatably mounted in the base body, and the drive shaft is inserted into the drive flange and engages with the drive flange in a transmission cooperation. The transmission shaft has a worm gear section on its shaft body, and the gripper module is provided with a turbine structure that meshes with the worm gear section for transmission.

[0008] In some embodiments, the gripper module includes: A variable cell mechanism is disposed on the substrate and rotates with the substrate. The variable cell mechanism is driven and connected to the drive module and has a switchable parallel yaw mode and a bending deformation mode. The parallel yaw mode corresponds to the row clamping mode, and the bending deformation mode corresponds to the envelope clamping mode. The clamping finger is disposed on the variable cell mechanism.

[0009] In some embodiments, the variable cell mechanism includes: A first variable-cell crank is hinged to the base and driven by the drive module, and the first variable-cell crank and the base have a decoupled first hinge portion. The second variable cell crank is hinged to the base and arranged on the side of the first variable cell crank facing inward. The second variable cell crank and the base have a decoupled second hinge portion. A drive link, the two ends of which are respectively hinged to the end of the first variable cell crank away from the base and the end of the second variable cell crank away from the base, and the drive link is provided with the clamping finger; When the first hinge and the second hinge are decoupled, the variable cell mechanism switches from the parallel yaw mode to the bending deformation mode.

[0010] In some embodiments, the first variable-cell crank includes a first crank member, a second crank member, and a decoupling pin. The first crank member and the second crank member are hinged to form the first hinge portion. The end of the first crank member away from the second crank member is hinged to the base and driven to the drive module. The end of the second crank member away from the first crank member is hinged to the drive connecting rod. When the first hinge is not decoupled, the decoupling pin is arranged at the first hinge and detachably connects the first crank component and the second crank component.

[0011] In some embodiments, the second variable-cell crank includes a third crank member, a fourth crank member, and a damping member. The third crank member and the fourth crank member are hinged together to form the second hinge portion. One end of the third crank member away from the fourth crank member is hinged to the base, and one end of the fourth crank member away from the third crank member is hinged to the drive connecting rod. The damping member is disposed at the hinge between the third crank member and the fourth crank member and provides elastic resistance. Specifically, when the rotational torque between the third crank component and the fourth crank component is greater than the resistance torque provided by the damping component, the second hinge portion completes decoupling.

[0012] To achieve the above objectives, a second aspect of this application provides a gripper control method applied to a gripper device according to the first aspect above, the gripper control method including a parallel gripping method and an envelope gripping method; The parallel clamping method includes: Switch the gripper module to the parallel gripping mode, and when the gripper module is not in contact with the object to be gripped, control the motor to run in the position control mode; When the operating current of the motor reaches the first operating threshold within a first preset time, the position control mode is switched to the torque control mode and the operating current of the motor is controlled to remain within the first safety threshold. The envelope clamping method includes: Switch the gripper module to the envelope gripping mode, and when the gripper module is not in contact with the object to be gripped, control the motor to run in the position control mode; If the operating current of the motor reaches the second operating threshold within a second preset time, the position control mode is switched to the torque control mode and the operating current of the motor is controlled to remain within the second safety threshold.

[0013] As a further improvement to the above technical solution: In some embodiments, both the parallel clamping method and the envelope clamping method further include: When the operating current of the motor reaches the target threshold, the motor is controlled to stop working so that the gripper module can maintain its grip on the object.

[0014] To achieve the above objectives, a third aspect of this application provides a robot including a gripper device according to the first aspect described above.

[0015] Compared with the prior art, the gripper device, gripper control method and robot provided in this application have at least the following technical advantages: The gripper module in the gripper device provided in this application has switchable parallel gripping mode and envelope gripping mode. The drive module has a built-in motor and is used to drive at least two gripper modules to simultaneously execute parallel gripping mode or envelope gripping mode, thus making it applicable to grippers of different shapes and improving its practicality. Furthermore, when executing parallel gripping mode, the control module of this application acquires the motor's operating current. If the operating current reaches a first operating threshold within a first preset time, the position control mode is switched to torque control mode, and the motor's operating current is maintained within a first safety threshold. When executing envelope gripping mode, the control module acquires the motor's operating current. If the operating current reaches a second operating threshold within a second preset time, the position control mode is switched to torque control mode, and the motor's operating current is maintained within a second safety threshold. Thus, the gripper device provided in this application, based on a current feedback control mechanism, achieves precise control of the gripping force without relying on external specific sensors, improving the scalability of the hardware and software, simplifying the structure and control logic, thereby reducing hardware costs and increasing system reliability. In addition, after clamping an object, the operating current is maintained within the range of the first safety threshold and the second safety threshold, which can ensure safety when gripping precision or fragile objects.

[0016] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the following detailed description to explain the embodiments of this application, but do not constitute a limitation on the embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without any inventive effort. In the drawings: Figure 1 This is a schematic diagram illustrating the state of a gripper device holding a cube-shaped object, as provided in an embodiment of this application. Figure 2 An exploded view of a portion of the drive module and the base structure in the gripper device provided in the embodiments of this application; Figure 3 An exploded view of a portion of the gripper module and the base structure in the gripper device provided in the embodiments of this application; Figure 4 for Figure 2 A partially enlarged schematic diagram of the structure at point A; Figure 5 A schematic diagram of the gripper device in the embodiment of this application holding a cylindrical object; Figure 6 This is a flowchart illustrating a gripper control method provided in an embodiment of this application.

[0018] Explanation of reference numerals in the attached figures 100. Matrix; 200. Gripper module; 210. Variable cell mechanism; 211. First variable cell crank; 2110. First hinge; 2111. First crank component; 2111a. Rod section; 2111b. Hinge section; 2111c. Drive section; 2112. Second crank component; 2113. Decoupling pin; 212. Second variable cell crank; 2120. Second hinge; 2121. Third crank component; 2122. Fourth crank component; 2123. Damping component; 213. Drive connecting rod; 220. Gripper finger; 300. Drive module; 310. Joint module; 320. Mechanical transmission module; 321. Transmission flange; 322. Transmission shaft; 3220. Worm gear section. Detailed Implementation

[0019] The specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this application.

[0020] The present application will now be described in detail with reference to the accompanying drawings and exemplary embodiments.

[0021] On the one hand, please refer to Figure 1This embodiment provides a gripper device, and more particularly relates to a dexterous hand structure. The gripper device can switch between parallel gripping and envelope gripping of an object.

[0022] In this embodiment, the gripper device includes a base 100, a drive module 300, a control module, and at least two gripper modules 200. The at least two gripper modules 200 are movably mounted on the base 100, and each gripper module 200 has a switchable parallel gripping mode and an envelope gripping mode. The drive module 300 has a built-in motor, is mounted on the base 100, and drives and connects to the at least two gripper modules 200 respectively. The drive module 300 is used to drive all gripper modules 200 to synchronously execute either the parallel gripping mode or the envelope gripping mode.

[0023] The control module is communicatively connected to the motor in the drive module 300 and has switchable position control mode and torque control mode. Specifically, in parallel clamping mode, the control module is configured to acquire the motor's operating current, and if the operating current reaches a first operating threshold within a first preset time, switch the position control mode to torque control mode and maintain the motor's operating current within a first safety threshold. In envelope clamping mode, the control module is configured to acquire the motor's operating current, and if the operating current reaches a second operating threshold within a second preset time, switch the position control mode to torque control mode and maintain the motor's operating current within a second safety threshold.

[0024] Thus, the gripper module 200 in the gripper device provided in this embodiment has switchable parallel gripping mode and enveloping gripping mode, and the drive module 300 has a built-in motor. According to the gripping requirements of different objects, the gripper module 200 can be pre-switched to the corresponding gripping mode, and then the drive module 300 drives all gripper modules 200 to synchronously execute the parallel gripping mode (e.g., ...). Figure 1 (as shown) or envelope clamping mode (such as) Figure 5 As shown in the figure, it is designed to be suitable for clamping objects of different shapes, making it more practical.

[0025] Furthermore, in the parallel clamping mode, the control module acquires the motor's operating current in real time. If the operating current reaches a first operating threshold within a first preset time, the position control mode is switched to torque control mode, and the motor's operating current is maintained within a first safety threshold. In the envelope clamping mode, the control module acquires the motor's operating current. If the operating current reaches a second operating threshold within a second preset time, the position control mode is switched to torque control mode, and the motor's operating current is maintained within a second safety threshold. Thus, the gripper device provided in this embodiment, based on a current feedback control mechanism, achieves precise control of the clamping force without relying on external sensors, is not limited by external sensors, improves the scalability of hardware and software, simplifies the structure and control logic, thereby reducing hardware costs and increasing system reliability. Furthermore, after clamping an object, the operating current is maintained within the first and second safety thresholds, thus ensuring safety when gripping precision or fragile objects.

[0026] To more clearly describe the technical solution of this application, the gripper device provided in this embodiment is described in detail below: Please see Figure 1 and Figure 2 The aforementioned drive module 300 includes a joint module 310 and a mechanical transmission module 320. The joint module 310 houses a motor and a reducer. The reducer is connected to the output shaft of the motor, and its output is connected to the input side of the mechanical transmission module 320. The output side of the mechanical transmission module 320 is connected to the gripper module 200. Thus, the joint module transmits power to all gripper modules via the mechanical transmission module 320, enabling all gripper modules to operate synchronously.

[0027] The mechanical transmission module 320 includes a transmission flange 321 and a transmission shaft 322. The transmission flange 321 is connected to the output end of the reducer in the joint module 310. The transmission shaft 322 is rotatably mounted in the base 100 via bearings, and is inserted into the transmission flange 321 and engages with it in a transmission manner.

[0028] In some embodiments, the outer peripheral surface of one end of the drive shaft 322, which is inserted into the drive flange 321, is provided with a toothed structure. A through hole for insertion of the drive shaft 322 is provided in the middle of the drive flange 321, and the peripheral wall of the through hole is provided with a toothed groove adapted to the toothed structure. Optionally, the drive shaft 322 can be splined with the drive flange 321, or a similar mating structure as a "D" hole and a "D" shaft can be used. It should be understood that the above are merely illustrative examples and are not intended to limit the scope of protection of this application.

[0029] Furthermore, a worm gear section 3220 is constructed on the shaft body of the drive shaft 322 (see...). Figure 2 The gripper module 200 is provided with a turbine structure that meshes with the worm section 3220 (described below).

[0030] The gripper device can be a two-finger structure (i.e., two gripper modules 200) or a multi-finger structure (i.e., multiple gripper modules 200). In this embodiment, to more clearly describe the technical solution of this application, a two-finger gripper device is used as an example for illustration.

[0031] Please refer to the following: Figure 3 , Figure 4 and Figure 5 Therefore, one of the two gripper modules 200 will be described. Each gripper module 200 includes a variable-cell mechanism 210 and gripper fingers 220. The variable-cell mechanism 210 is mounted on the base 100 and rotatably engages with it. The variable-cell mechanism 210 is driven by the drive module 300 and has switchable parallel yaw mode and bending deformation mode. The parallel yaw mode corresponds to the row gripping mode, and the bending deformation mode corresponds to the envelope gripping mode. The gripper fingers 220 are mounted on the variable-cell mechanism 210 and can move along with it.

[0032] Thus, as Figure 1 As shown, when the parallel gripping mode needs to be executed, the variable cell mechanism 210 can be switched to the parallel swing mode. At this time, the drive module 300 can drive the variable cell mechanism 210 to drive the gripper fingers 220 to swing in parallel, so that the gripper fingers 220 in the two gripper modules 200 grip the object in parallel. Figure 5 As shown, when the enveloping clamping mode is required, the variable-cell mechanism 210 is switched to the bending deformation mode. At this time, the drive module 300 can drive the variable-cell mechanism 210 to bend the gripper fingers 220 inwards, so that the entire gripper module 200 envelops and clamps the object. Therefore, the switching between the two modes of the variable-cell mechanism 210 corresponds to the switching between parallel clamping and enveloping clamping operations, satisfying different operating modes. Furthermore, by utilizing the variable-cell mechanism 210 to switch the degrees of freedom of the gripper module 200, the structural coupling of the gripper module 200 is improved, the clamping force is guaranteed, and it is suitable for clamping large or heavy objects, thereby improving adaptability and clamping stability.

[0033] Please see Figure 3The aforementioned variable-cell mechanism 210 includes a first variable-cell crank 211, a second variable-cell crank 212, and a drive connecting rod 213. The first variable-cell crank 211 is hinged to the base 100 and driven by the drive module 300. The first variable-cell crank 211 has a decoupled first hinge portion 2110. That is, before decoupling, the first hinge portion 2110 on the first variable-cell crank 211 has no rotational degree of freedom. After decoupling, the first variable-cell crank 211 can be freely bent at the first hinge portion 2110, thus increasing the bending degree of freedom of the first variable-cell crank 211.

[0034] The second variable-cell crank 212 is hinged to the base 100 and arranged on the inward side of the first variable-cell crank 211. The second variable-cell crank 212 has a decoupled second hinge portion 2120. Similarly, the second hinge portion 2120 on the second variable-cell crank 212 does not have rotational freedom before decoupling. After decoupling, the second variable-cell crank 212 can bend freely at the second hinge portion 2120, thereby increasing the bending freedom of the second variable-cell crank 212.

[0035] The two ends of the drive link 213 are respectively hinged to the end of the first variable cell crank 211 away from the base 100 and the end of the second variable cell crank 212 away from the base 100. The drive link 213 is provided with a clamping finger 220.

[0036] Optionally, the gripper finger 220 is detachably mounted on the drive link 213. This allows the gripper finger 220 to be replaced depending on the object being gripped, such as replacing a rigid gripper finger with a flexible gripper finger, or replacing gripper fingers 220 of different shapes, etc.

[0037] It should be noted that when the first hinge part 2110 and the second hinge part 2120 are not decoupled, the first variable cell crank 211, the second variable cell crank 212, the drive link 213 and the base 100 constitute a four-bar linkage with a parallelogram structure. In this way, the variable cell mechanism 210 can perform parallel swing under the drive of the drive module 300, that is, the variable cell mechanism 210 is in the parallel swing mode at this time. When the first hinge 2110 and the second hinge 2120 are decoupled, the variable cell mechanism 210 switches from the parallel yaw mode to the bending deformation mode. At this time, the first hinge 2110 and the second hinge 2120 are decoupled at the same time, and the degrees of freedom of the first variable cell crank 211 and the second variable cell crank 212 are released. The variable cell mechanism 210 will change from a four-bar linkage to a multi-bar linkage (e.g., a six-bar linkage). Under the drive of the drive module 300, the variable cell mechanism 210 can drive the gripper 220 to bend and envelop the object together, thereby realizing the switch from the parallel yaw mode to the bending deformation mode.

[0038] Specifically, the first variable-cell crank 211 includes a first crank member 2111, a second crank member 2112, and a decoupling pin 2113. The first crank member 2111 and the second crank member 2112 are hinged to form a first hinge portion 2110. The end of the first crank member 2111 away from the second crank member 2112 is hinged to the base 100 and driven by the drive module 300. The end of the second crank member 2112 away from the first crank member 2111 is hinged to the drive connecting rod 213. When the first hinge portion 2110 is not decoupled, the decoupling pin 2113 is arranged in the first hinge portion 2110 and detachably connects the first crank member 2111 and the second crank member 2112.

[0039] Understandably, when the decoupling pin 2113 connects the first crank component 2111 and the second crank component 2112, the decoupling pin 2113 restricts the rotation of the first crank component 2111 and the second crank component 2112 relative to the first hinge portion 2110. At this time, the first crank component 2111 and the second crank component 2112 can swing as a whole. When it is necessary to release the rotational freedom of the first crank component 2111 and the second crank component 2112 relative to the first hinge portion 2110, it can be done by disassembling the decoupling pin 2113. The decoupling pin 2113 can be implemented by a plug-in / pull-out mechanism or can be removed manually.

[0040] Please see Figure 3 and Figure 4 The first crank component 2111 includes a rod section 2111a, a hinge section 2111b, and a drive section 2111c connected as a single unit. The rod section 2111a is hinged to the second crank component 2112, the hinge section 2111b is hinged to the base 100, and the drive section 2111c is drivenly connected to the drive module 300. The hinge section 2111b is pivotally connected to the base 100. To further reduce friction during rotation, a bushing or bearing can be provided at the pivot connection. In this embodiment, a bearing is selected.

[0041] Please see Figure 2 , Figure 3 and Figure 4 Furthermore, the drive section 2111c is part of a circle and has a turbine structure (similar to an incomplete gear structure) constructed on its outer circumference. The worm section 3220 of the drive shaft 322 in the drive module 300 meshes with the turbine structure on the drive section 2111c for transmission.

[0042] Please see Figure 1 and Figure 3The second variable-cell crank 212 includes a third crank member 2121, a fourth crank member 2122, and a damping member 2123. The third crank member 2121 and the fourth crank member 2122 are hinged to form a second hinge portion 2120. The end of the third crank member 2121 away from the fourth crank member 2122 is hinged to the base 100, and the end of the fourth crank member 2122 away from the third crank member 2121 is hinged to the drive connecting rod 213. The damping member 2123 is disposed at the hinge between the third crank member 2121 and the fourth crank member 2122 and provides elastic resistance.

[0043] Thus, when the rotational torque between the third crank component 2121 and the fourth crank component 2122 is less than or equal to the resistance torque provided by the damping component 2123, the third crank component 2121 and the fourth crank component 2122 are constrained into a rigid rod by the damping component 2123, and at this time, the third crank component 2121 and the fourth crank component 2122 can oscillate synchronously relative to the base 100. When the rotational torque between the third crank component 2121 and the fourth crank component 2122 is greater than the resistance torque provided by the damping component 2123, the second hinge portion 2120 automatically completes decoupling, and at this time, the third crank component 2121 and the fourth crank component 2122 can overcome the elastic resistance and rotate relative to the second hinge portion 2120, thereby releasing their own rotational degrees of freedom. When the rotational torque between the third crank component 2121 and the fourth crank component 2122 is removed or becomes less than the resistance torque, the third crank component 2121 and the fourth crank component 2122 automatically reset under the elastic resistance provided by the damping component 2123.

[0044] Furthermore, the third crank component 2121 is pivotally connected to the base 100. In this embodiment, to reduce friction during rotation, a bushing or bearing can be provided at the pivot connection. In this embodiment, a bushing is used to save installation space. The bushing can be made of copper, such as a graphite copper bushing.

[0045] It should also be noted that when the decoupling pin 2113 and the damping element 2123 are decoupled simultaneously, the entire variable-cell mechanism 210, driven by the drive module 300, not only swings but also bends inward, causing the gripper fingers 220 to swing (non-parallel movement). The tips of the gripper fingers 220 approach each other, thus actively and adaptively conforming to the object surface and actively enveloping the object. This variable-cell mechanism allows the gripper to automatically adapt to the shape changes of complex curved surfaces, increasing the contact area and reducing the local pressure on the target object surface, making it particularly suitable for slippery, soft, fragile, or irregularly shaped workpieces. When the decoupling pin 2113 is not disassembled, the drive module 300 drives the variable-cell mechanism 210 to move the gripper fingers 220 to clamp the object in parallel. At this time, the third crank element 2121 and the fourth crank element 2122 will provide a certain reaction force to the gripper fingers 220 to overcome the resistance of the damping element 2123, thereby ensuring that the gripper fingers 220 clamp the object better. When the decoupling pin 2113 is not disassembled, the drive module 300 drives the variable cell mechanism 210 to contact the object. At this time, the object is located between the third crank component 2121 and the fourth crank component 2122. The third crank component 2121 and the fourth crank component 2122 are subjected to the reaction force given by the object to overcome the resistance provided by the damping component 2123, forming a passive envelope of the object.

[0046] Optionally, the damping element 2123 may be a torsion spring or a damping hinge.

[0047] On the other hand, please see Figures 1 to 6 This embodiment also provides a gripper control method applied to the aforementioned gripper device. The gripper control method includes a parallel gripping method and an envelope gripping method.

[0048] Among them, such as Figure 6 As shown, the parallel clamping method includes the following steps: S110: Switch the gripper module 200 to parallel gripping mode, and control the motor to run in position control mode when the gripper module 200 is not in contact with the object to be gripped.

[0049] S120: When the motor's operating current reaches the first operating threshold within a first preset time, switch the position control mode to the torque control mode and control the motor's operating current to remain within the first safety threshold.

[0050] like Figure 6 As shown, the above-mentioned envelope clamping method includes the following steps: S210: Switch the gripper module 200 to the envelope gripping mode, and when the gripper module 200 is not in contact with the object to be gripped, control the motor to run in the position control mode.

[0051] S220: When the motor's operating current reaches the second operating threshold within a second preset time, the position control mode is switched to the torque control mode and the motor's operating current is maintained within the second safety threshold.

[0052] Understandably, in parallel clamping or envelope clamping modes, when any of the gripping fingers 220 contacts the object to be clamped, the movement of the gripping fingers 220 is hindered, and the required output torque of the motor increases significantly. Specifically, this manifests as an increase in the motor's operating current. Current relative to the free motion stage (the stage before contact with an object) A significant increase occurred, meaning the motor's operating current... Exceeding the operating current based on free motion within a certain continuous sampling period A defined threshold range is used to determine whether the gripper module 200 has established contact with the object. The specific judgment conditions are as follows:

[0053] in, This is an empirical coefficient; .

[0054] Once contact is established, the control module automatically transitions from position-driven adjustment to a force-position hybrid control mode (torque control mode) by limiting the maximum operating current of the drive motor. This makes the motor's operating current This ensures that the clamping force is kept within a safe range while maintaining the synchronization of the closed loop positions on both sides. This allows the gripper module 200 to achieve stable clamping while maintaining the symmetry of the fingertips, thereby ensuring that the cube object is clamped in a reliable posture.

[0055] Furthermore, both the parallel clamping method and the envelope clamping method also include: When the operating current of the motor reaches the target threshold, the motor is controlled to stop working so that the gripper module 200 can maintain the gripping of the object.

[0056] Understandably, after the motor stops working, the object is held in a clamping state by relying on the self-locking of the worm gear.

[0057] The gripper control method provided in this embodiment does not employ external sensors such as fingertip force sensors or joint side force sensors. It relies solely on a drive motor current feedback control strategy to indirectly estimate external contact forces and automatically switches from position-dominant to force-position hybrid during gripping. This control method not only simplifies the structure and reduces costs but also combines the positioning accuracy of parallel gripping with the compliant capability of active envelope. It can adapt to the gripping needs of objects of different shapes, significantly improving the adaptability and versatility of the gripper in complex environments.

[0058] Furthermore, this embodiment also provides a robot. The robot includes the gripper device described above.

[0059] Compared to existing technologies, the robot provided in this embodiment has the following advantages: (1) The parallelogram-structured variable cell mechanism 210, when the decoupling pin 2113 is set as a detachable solution and the damping element 2123 is a damping element 2123, the gripper can achieve traditional parallel gripping, switch to active envelope gripping, and automatically trigger passive degrees of freedom to complete envelope gripping after the variable cell mechanism 210 contacts the object. Compared with existing grippers that can only achieve translational gripping or fixed opening and closing mechanisms, this embodiment can adapt to various shapes such as cuboids, cylinders, and irregular objects, significantly improving the versatility and adaptability of gripping.

[0060] (2) In this embodiment, a worm gear drive is adopted, and the driving torque is directly output through the joint module 310, so that the two gripper modules 200 maintain a high degree of synchronization and symmetry. Compared with the structure that relies on complex multi-stage linkages or multi-motor coordination, this embodiment has a shorter transmission chain, higher motion accuracy, and a more compact structure, which is conducive to improving the smoothness of the gripping action and the repeatability of the positioning accuracy.

[0061] (3) In the control method, the external contact force is estimated by monitoring the working current of the motor, and combined with the passive compliant degree of freedom provided by the torsion spring, a compliant grasping effect similar to force control is achieved. Compared with the solution that relies on external sensors, the hardware cost of this embodiment is significantly reduced, the system reliability is higher, and the safety can still be guaranteed when grasping precision or fragile objects.

[0062] (4) Through the passive envelope capability provided by the torsion spring and the contact detection mechanism based on current feedback, this embodiment can achieve natural alignment and contact with the target without precise target attitude estimation. Compared with existing grippers that require high-precision positioning or mechanical alignment, this embodiment can effectively compensate for target position errors, installation errors and slight alignment deviations during gripping, thereby improving the overall gripping success rate.

[0063] (5) This embodiment adopts a force-position hybrid collaborative control strategy and performs force estimation entirely based on current feedback, so that the control process does not require external complex sensors or additional communication interfaces. Compared with grippers that require independent force control modules or complex sensor fusion algorithms, the control logic of this embodiment is simpler, the implementation cost is lower, and it can be directly integrated into the robot's controller to achieve high scalability with plug and play.

[0064] It should be noted that, in this application, unless otherwise stated, the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" used to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0065] As will be understood by those skilled in the art, the control module may be a PLC controller or a microcontroller, which are well known to those skilled in the art and are not part of the core improvement of this application, and therefore will not be described in detail here.

[0066] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0067] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0068] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0069] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A gripper device, characterized in that, include: Matrix (100); At least two gripper modules (200) are movably mounted on the base (100), and the gripper modules (200) have switchable parallel gripping mode and envelope gripping mode; The drive module (300) has a built-in motor. The drive module (300) is disposed on the base (100) and drives and connects at least two gripper modules (200) respectively. It is used to drive at least two gripper modules (200) to synchronously execute the parallel gripping mode or the envelope gripping mode. The control module is communicatively connected to the motor and has switchable position control mode and torque control mode; In the parallel clamping mode, the control module is configured to acquire the operating current of the motor, and if the operating current reaches a first operating threshold within a first preset time, switch the position control mode to the torque control mode and control the operating current of the motor to remain within the first safety threshold. When the envelope clamping mode is executed, the control module is configured to acquire the operating current of the motor, and when the operating current reaches the second operating threshold within a second preset time, switch the position control mode to the torque control mode and control the operating current of the motor to be maintained within the second safety threshold.

2. The gripper device according to claim 1, characterized in that, The drive module (300) includes The joint module (310) has the motor built into it; The mechanical transmission module (320) is driven to the output end of the joint module (310) via its input side, and to the gripper module (200) via its output side.

3. The gripper device according to claim 2, characterized in that, The mechanical transmission module (320) includes: The transmission flange (321) is connected to the output end of the joint module (310) in a transmission manner; A drive shaft (322) is rotatably disposed within the base (100), and the drive shaft (322) is inserted into the drive flange (321) and engages with the drive flange (321) in a transmission cooperation. The drive shaft (322) has a worm section (3220) on its shaft body, and the gripper module (200) is provided with a turbine structure that meshes with the worm section (3220) for transmission.

4. The gripper device according to claim 1, characterized in that, The gripper module (200) includes: A variable cell mechanism (210) is disposed on the substrate (100) and rotates in cooperation with the substrate (100). The variable cell mechanism (210) is driven connected to the drive module (300) and has switchable parallel yaw mode and bending deformation mode, wherein the parallel yaw mode corresponds to the row clamping mode and the bending deformation mode corresponds to the envelope clamping mode. The clamping finger (220) is disposed on the variable cell mechanism (210).

5. The gripper device according to claim 4, characterized in that, The variable cell mechanism (210) includes: A first variable-cell crank (211) is hinged to the base (100) and drivenly connected to the drive module (300). The first variable-cell crank (211) and the base have a decoupled first hinge portion (2110). The second variable cell crank (212) is hinged to the base (100) and arranged on the side of the first variable cell crank (211) facing inward. The second variable cell crank (212) and the base have a decoupled second hinge (2120). A drive link (213) is provided with the following two ends: one end of the first variable cell crank (211) away from the base (100) and the other end of the second variable cell crank (212) away from the base (100). The drive link (213) is provided with the clamping finger (220). When the first hinge (2110) and the second hinge (2120) are decoupled, the variable cell mechanism (210) switches from the parallel yaw mode to the bending deformation mode.

6. The gripper device according to claim 5, characterized in that, The first variable-cell crank (211) includes a first crank element (2111), a second crank element (2112), and a decoupling pin (2113). The first crank element (2111) and the second crank element (2112) are hinged to form the first hinge portion (2110). The end of the first crank element (2111) away from the second crank element (2112) is hinged to the base (100) and driven to the drive module (300). The end of the second crank element (2112) away from the first crank element (2111) is hinged to the drive connecting rod (213). When the first hinge (2110) is not decoupled, the decoupling pin (2113) is arranged on the first hinge (2110) and detachably connects the first crank (2111) and the second crank (2112).

7. The gripper device according to claim 5, characterized in that, The second variable-cell crank (212) includes a third crank member (2121), a fourth crank member (2122), and a damping member (2123). The third crank member (2121) and the fourth crank member (2122) are hinged to form the second hinge portion (2120). One end of the third crank member (2121) away from the fourth crank member (2122) is hinged to the base (100). One end of the fourth crank member (2122) away from the third crank member (2121) is hinged to the drive connecting rod (213). The damping member (2123) is disposed at the hinge between the third crank member (2121) and the fourth crank member (2122) and provides elastic resistance. When the rotational torque between the third crank member (2121) and the fourth crank member (2122) is greater than the resistance torque provided by the damping member (2123), the second hinge part (2120) completes decoupling.

8. A gripper control method, characterized in that, The gripper device according to any one of claims 1-7, wherein the gripper control method includes a parallel gripping method and an envelope gripping method; The parallel clamping method includes: Switch the gripper module (200) to the parallel gripping mode, and when the gripper module (200) is not in contact with the object to be gripped, control the motor to run in the position control mode; When the operating current of the motor reaches the first operating threshold within a first preset time, the position control mode is switched to the torque control mode and the operating current of the motor is controlled to remain within the first safety threshold. The envelope clamping method includes: Switch the gripper module (200) to the envelope gripping mode, and when the gripper module (200) is not in contact with the object to be gripped, control the motor to run in the position control mode; If the operating current of the motor reaches the second operating threshold within a second preset time, the position control mode is switched to the torque control mode and the operating current of the motor is controlled to remain within the second safety threshold.

9. The gripper control method according to claim 8, characterized in that, Both the parallel clamping method and the envelope clamping method further include: When the operating current of the motor reaches the target threshold, the motor is controlled to stop working so that the gripper module (200) can maintain the gripping of the object.

10. A robot, characterized in that, Includes the gripper device according to any one of claims 1-7.

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