Dielectric fiber driven gripper

Abstract

The utility model discloses a kind of dielectric fiber driven grippers, including mounting base and the assembly on the mounting base of several clamping jaw mechanisms, all the clamping jaw mechanisms are distributed along circumference, to realize the automatic centring of object and catch;Each the clamping jaw mechanism includes hingedly connected first clamping jaw and second clamping jaw, and the first dielectric fiber driver for controlling the centripetal or centrifugal motion of the first clamping jaw is connected between the first clamping jaw and the second clamping jaw;The second clamping jaw is assembled on the mounting base.The utility model successfully provides a kind of gripper solution with low driving voltage, simple structure, light weight, high reliability and good grasping adaptability by combining low-voltage dielectric fiber driver with optimized design rigid clamping jaw mechanism, and it has excellent comprehensive performance and good application value.

Description

Technical Field

[0001] This utility model belongs to the field of robotics technology, and more specifically, relates to a robot end effector, particularly a dielectric fiber driven gripper. Background Technology

[0002] The gripper (i.e., the grasping gripper) is the end effector of a robot and a key component for interacting with the physical environment. Its performance directly affects the robot's operational capabilities. Grippers based on rigid linkages and hinges still dominate in fields such as industrial automation and precision material handling due to their advantages of structural stability, high load capacity, and high positioning accuracy.

[0003] However, such traditional rigid grippers have some inherent drawbacks that have long remained unresolved: First, its drive and transmission system is complex. To achieve the gripping action, a drive source such as a motor or cylinder is usually installed on the gripper body or at its distal end, along with a complex reducer, gears, lead screws, synchronous belts, or linkage mechanisms to transmit and convert the rotational or linear motion of the drive source into the gripping action of the gripping fingers. This complex mechanical transmission structure leads to problems such as high manufacturing costs, large overall weight, and inconvenient maintenance. At the same time, too many moving joints and transmission components also introduce more wear, backlash, and potential failure points, affecting the reliability and lifespan of the system.

[0004] Secondly, in pursuit of structural compactness, the design of directly integrating components such as drive motors into the finger joints leads to increased hand inertia and decreased dynamic response performance. Furthermore, arranging numerous components in a confined space places extremely high demands on design and manufacturing processes.

[0005] To address the aforementioned transmission complexity, researchers have turned to direct actuation schemes based on functional materials such as dielectric elastomers. However, the mainstream technical approach aims to construct completely flexible grippers, entirely composed of soft materials that deform to envelop the target object. While these purely soft grippers solve the transmission complexity problem, they generally suffer from relatively limited load capacity, making it difficult to meet the basic requirements of many industrial scenarios. More seriously, they typically require ultra-high drive voltages in the thousands of volts (kV) range, which not only poses significant electrical safety hazards but also necessitates expensive and bulky high-voltage drive and insulation systems, rendering them impractical and uneconomical in most industrial applications. Utility Model Content

[0006] To address the aforementioned shortcomings in the existing technology, this utility model aims to provide a dielectric fiber driven gripper, thereby simplifying the structure and improving operational safety.

[0007] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a dielectric fiber driven gripper, including a mounting base and a plurality of gripper mechanisms mounted on the mounting base, all of which are distributed circumferentially to achieve automatic centering gripping of objects; Each of the gripper mechanisms includes a first gripper and a second gripper that are hinged together, and a first dielectric fiber actuator connected between the first gripper and the second gripper for controlling the centripetal or centrifugal movement of the first gripper. The second gripper is mounted on the mounting base.

[0008] As a limitation of this utility model, the first dielectric fiber actuator is a PDMS fiber actuator capable of low-voltage driving, and is in the shape of a hollow cylinder with a wall thickness of 30-70 μm.

[0009] As another limitation of this utility model, the second gripper includes a first connecting rod, and the tail end of the first connecting rod is provided with a first inclined groove; The tail end of the first gripper is provided with a first fiber curing hole; The first dielectric fiber driver is distributed along the length of the first connecting rod, and one end of the first dielectric fiber driver is fixed in the first fiber curing hole, and the other end is fixed on the first inclined groove.

[0010] As a further limitation of this utility model, the first connecting rod is provided with a through hole for reducing weight.

[0011] As a third limitation of this utility model, the second gripper includes a second link and a third link that are hinged together, and a second dielectric fiber actuator connected between the second link and the third link for controlling the centripetal or centrifugal movement of the second link. The third link is assembled on the mounting base; the second link is hinged to the first gripper. The first dielectric fiber driver is connected between the second link and the first gripper.

[0012] As a further limitation of this utility model, the tail end of the first gripper is provided with a first fiber curing hole, and the tail end of the second connecting rod is provided with a second inclined groove. The first dielectric fiber driver is distributed along the length of the second connecting rod, and one end of the first dielectric fiber driver is fixed in the first fiber curing hole, and the other end is fixed on the second inclined groove.

[0013] As a further limitation of this utility model, the middle part of the second link is hinged to the front end of the third link; The second connecting rod has a second fiber curing hole in the middle, and the third connecting rod has a third inclined groove at the tail end; The second dielectric fiber actuator is distributed along the length of the third link, and one end of the second dielectric fiber actuator is fixed in the second fiber curing hole, and the other end is fixed on the third inclined groove.

[0014] As a further limitation of this utility model, both the second link and the third link are provided with through holes for reducing weight.

[0015] As a further limitation of this utility model, the front end of the first gripper has a flexible front section made of silicone or rubber.

[0016] As a further limitation of this utility model, the mounting base is a disc-shaped structure with a plurality of elongated holes distributed circumferentially for assembling the second gripper, and the length direction of each elongated hole is consistent with the radial direction of the mounting base. The mounting base has a protrusion at the center of its top surface for clamping the moving device.

[0017] By adopting the above-mentioned technical solution, the beneficial effects achieved by this utility model compared with the prior art are as follows: (1) This utility model creatively utilizes a dielectric fiber actuator to directly drive the gripper mechanism, completely eliminating the need for complex mechanical transmission components such as traditional motors, reducers, and gears. This fundamentally solves the problems of complex structure, high cost, and difficult maintenance of traditional rigid grippers. Furthermore, by setting through holes on the connecting rods constituting the gripper mechanism to reduce weight, the material usage is effectively reduced and the overall mass of the gripper is lowered while ensuring structural strength. The weight reduction directly means a reduction in the preload applied to the dielectric fiber actuator, allowing the output force of the dielectric fiber actuator to be used more efficiently for external work, thereby significantly improving the effective load capacity of this utility model under the same driving conditions.

[0018] (2) This utility model uses a low-voltage dielectric fiber actuator (PDMS fiber actuator) as the core driving source, requiring only 500V to achieve effective gripping. Compared with the dielectric elastomers that usually require thousands of volts of ultra-high driving voltage in the prior art, the driving voltage is reduced by an order of magnitude. The significant reduction in voltage greatly eliminates the safety hazard of electric shock caused by high voltage, while allowing the use of simpler, cheaper, and easier-to-miniaturize driving circuits, greatly improving the safety, practicality, and industrialization prospects of the entire gripper system.

[0019] (3) This utility model features an inclined groove on the connecting rod for fixing the dielectric fiber actuator. Compared with the traditional right-angle groove, this design effectively avoids the risk of the dielectric fiber actuator being cut or severed due to stress concentration at the fixing point, providing a gentle force transmission interface for the brittle dielectric fiber actuator. This detailed design greatly improves the reliability and durability of the dielectric fiber actuator during operation and extends the service life of the entire clamp.

[0020] (4) In this utility model, the front end of the first gripper is made of flexible materials such as silicone and rubber, forming a "rigid-flexible combination" configuration. The rigid part ensures the accuracy of movement and the efficiency of force transmission, while the flexible tip can adaptively conform to the surface of the object when gripping, which increases the contact area and friction, and avoids damage to the surface of precision, fragile or easily scratched workpieces (such as ceramic components, optical lenses, fruits, etc.), thus realizing "non-destructive gripping" and greatly expanding the application scenarios of this utility model.

[0021] In summary, this utility model, by combining a low-voltage dielectric fiber actuator with an optimized rigid gripper mechanism, successfully provides a gripper solution with low driving voltage, simple structure, light weight, high reliability, and good gripping adaptability. It has excellent overall performance and good application value. Attached Figure Description

[0022] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0023] Figure 1 This is a schematic diagram of the structure of an embodiment of the present utility model; Figure 2 This is a schematic diagram of the gripper mechanism in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of the mounting base in an embodiment of this utility model; Figure 4 and Figure 5 They are respectively similar to Figure 1 and Figure 2 The view shows a modified embodiment of the clamp of this utility model; Figure 6 yes Figure 4 and Figure 5 The illustrated schematic diagram shows the application structure of the variant embodiment; In the figure: 1. Mounting base; 2. Gripper mechanism; 3. Elongated hole; 4. Protrusion; 5. First gripper; 6. First connecting rod; 7. First dielectric fiber actuator; 8. First inclined groove; 9. First fiber curing hole; 10. Through hole; 11. Flexible front section; 12. Second connecting rod; 13. Third connecting rod; 14. Second dielectric fiber actuator; 15. Second fiber curing hole; 16. Third inclined groove; 17. Second inclined groove. Detailed Implementation

[0024] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0025] This embodiment discloses a dielectric fiber driven gripper, including a mounting base 1 and a plurality of gripper mechanisms 2 assembled on the mounting base 1. All gripper mechanisms 2 are distributed circumferentially. Under the drive of the dielectric fiber driver, the gripper mechanisms 2 can realize automatic centering gripping of objects.

[0026] Figures 1 to 3 The first embodiment of this utility model is shown. For example... Figure 3 As shown, in this embodiment, the mounting base 1 has a disc-shaped structure with several elongated holes 3 distributed circumferentially. The length direction of each elongated hole 3 is consistent with the radial direction of the mounting base 1. Each elongated hole 3 corresponds to a gripper mechanism 2. In actual assembly, the mounting position and angle of the gripper mechanism 2 on the elongated hole 3 are changed to adapt to gripping targets of different sizes. In this embodiment, the mounting base 1 has five elongated holes 3 distributed circumferentially. Furthermore, a protrusion 4 for gripping the moving device is fixed at the center of the top surface of the mounting base 1, so that the gripper can be moved by the moving device.

[0027] Five gripper mechanisms 2 are distributed circumferentially on the mounting base 1. Of course, the number of gripper mechanisms 2 can be increased or decreased as needed. In this embodiment, each gripper mechanism 2 includes a first gripper 5, a second gripper, and a first dielectric fiber actuator 7. The tail end of the first gripper 5 is hinged to the front end of the second gripper. The first dielectric fiber actuator 7 is connected between the first gripper 5 and the second gripper to control the centripetal or centrifugal movement of the first gripper 5.

[0028] The second gripper includes the first link 6, such as... Figure 1 As shown, the tail end of the first connecting rod 6 is fixed in the elongated hole 3 of the mounting base 1. In this embodiment, after determining the fixing position and angle of the tail end of the first connecting rod 6 in the elongated hole 3, it is fixed using a light-curing solution. Further, as... Figure 2As shown, the tail end of the first connecting rod 6 is provided with a first inclined groove 8, and the tail end of the first gripper 5 is provided with a first fiber curing hole 9. The aforementioned first dielectric fiber actuator 7 is distributed along the length direction of the first connecting rod 6, and one end of the first dielectric fiber actuator 7 is fixed in the first fiber curing hole 9, and the other end is fixed on the first inclined groove 8. In this embodiment, the fixing of the first dielectric limiting actuator in the first fiber curing hole 9 and the fixing on the first inclined groove 8 are both achieved by photocuring solution.

[0029] In this embodiment, the first connecting rod 6 is provided with a plurality of through holes 10 along the length direction to reduce weight, making the overall weight of the gripper mechanism 2 lighter, thereby reducing the preload of the first dielectric fiber actuator 7 and thus increasing the load.

[0030] The first gripper 5 has a flexible front section 11 at its front end, which can adaptively conform to the surface of the object during gripping, increasing the contact area and friction while avoiding damage to delicate, fragile, or easily scratched workpieces. In this embodiment, the flexible front section 11 is made of a flexible material such as silicone or rubber.

[0031] It should be noted that in this embodiment, "front end" refers to the downward-facing end of the structure, and "tail end" refers to the upward-facing end of the structure.

[0032] The first dielectric fiber actuator 7 is a PDMS fiber actuator capable of low-voltage driving (refer to the dielectric fiber actuator technology disclosed in the paper "Fiber-Format Dielectric Elastomer Actuators by the Meter"). It is a hollow cylinder with a wall thickness of 30–70 μm (generally, selectable sizes are 30 μm, 40 μm, 50 μm, 60 μm, and 70 μm, corresponding to different driving voltages). In this embodiment, "low-voltage driving" means that a minimum driving voltage of 500V can be achieved, which greatly reduces the driving voltage of traditional dielectric elastomers.

[0033] When no voltage is applied, the first dielectric fiber actuator 7 is in a naturally relaxed or slightly pre-stretched state. After voltage is applied, a potential difference is generated between the inner and outer electrodes, producing Maxwell stress, which causes the fiber to elongate. Therefore, in actual use, after adjusting the pre-stretch of the first dielectric fiber actuator 7 according to actual needs (adjusting the pre-stretch can achieve changes in the opening and closing angle), the first dielectric fiber actuator 7 is energized, the gripper mechanism 2 opens, and after the power is turned off, the gripper mechanism 2 tightens, completing the gripping process.

[0034] Figures 4 to 6A variation of the first embodiment is shown as a second embodiment of the present invention. In this embodiment, the second gripper includes a second link 12 and a third link 13 hinged together, and a second dielectric fiber actuator 14 connected between the second link 12 and the third link 13 for controlling the centripetal or centrifugal movement of the second link 12. This structure of the second gripper can increase the swing angle of the first gripper 5, thereby expanding the gripping range and making it more adaptable.

[0035] Specifically, the middle part of the second link 12 is hinged to the front end of the third link 13. The tail end of the third link 13 is fixed in the elongated hole 3 of the mounting base 1, and the fixing method is the same as that of the first link 6 mentioned above, which will not be described again here; the front end of the second link 12 is hinged to the first gripper 5.

[0036] Furthermore, such as Figure 5 As shown, the second connecting rod 12 has a second fiber curing hole 15 in its middle, and the third connecting rod 13 has a third inclined groove 16 at its tail end. The aforementioned second dielectric fiber actuator 14 is distributed along the length direction of the third connecting rod 13, and one end of the second dielectric fiber actuator 14 is fixed in the second fiber curing hole 15, and the other end is fixed in the third inclined groove 16. The fixing method is the same as above, both achieved by photocuring solution.

[0037] In this embodiment, the first dielectric fiber actuator 7 is connected between the second link 12 and the first gripper 5. For example... Figure 5 As shown, the tail end of the first gripper 5 is provided with a first fiber curing hole 9, and the tail end of the second connecting rod 12 is provided with a second inclined groove 17. The first dielectric fiber actuator 7 is distributed along the length direction of the second connecting rod 12, and one end of the first dielectric fiber actuator 7 is fixed in the first fiber curing hole 9, and the other end is fixed on the second inclined groove 17. In this embodiment, the fixing of the first dielectric limiting actuator in the first fiber curing hole 9 and the fixing on the second inclined groove 17 are both achieved by photocuring solution.

[0038] In this embodiment, both the second link 12 and the third link 13 have multiple through holes 10 along their length to reduce weight. Furthermore, the second dielectric fiber actuator 14 is the same as the first dielectric fiber actuator 7 described above.

[0039] In this embodiment, the opening and closing angle of the first gripper 5 can be directly changed by adjusting the pre-tension of the first dielectric fiber actuator 7, and the opening and closing angle of the first gripper 5 can be indirectly changed by adjusting the pre-tension of the second dielectric fiber actuator 14 by changing the swing range of the second link 12, thereby adapting to different gripping scenarios.

[0040] like Figure 6 As shown, by adjusting the angle of the second link 12 and the first gripper 5, a 20mm ball can be gripped.

[0041] Because the dielectric fiber actuator is extremely thin and long, it is almost invisible in the drawings, so except for the attached drawings... Figure 2 and Figure 5 Except for the first dielectric fiber driver 7 and the second dielectric fiber driver 14, neither is shown.

[0042] It should be noted that the above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions described in the above embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A dielectric fiber driven gripper, characterized in that: It includes a mounting base and several gripper mechanisms mounted on the mounting base, all of which are distributed circumferentially to achieve automatic centering gripping of objects; Each of the gripper mechanisms includes a first gripper and a second gripper that are hinged together, and a first dielectric fiber actuator connected between the first gripper and the second gripper for controlling the centripetal or centrifugal movement of the first gripper. The second gripper is mounted on the mounting base.

2. The dielectric fiber driven gripper according to claim 1, characterized in that: The first dielectric fiber actuator is a PDMS fiber actuator capable of low-voltage driving, and is in the shape of a hollow cylinder with a wall thickness of 30-70 μm.

3. The dielectric fiber driven gripper according to claim 1 or 2, characterized in that: The second gripper includes a first connecting rod, and the tail end of the first connecting rod is provided with a first inclined groove; The tail end of the first gripper is provided with a first fiber curing hole; The first dielectric fiber driver is distributed along the length of the first connecting rod, and one end of the first dielectric fiber driver is fixed in the first fiber curing hole, and the other end is fixed on the first inclined groove.

4. The dielectric fiber driven gripper according to claim 3, characterized in that: The first connecting rod is provided with a through hole for reducing weight.

5. The dielectric fiber driven gripper according to claim 1 or 2, characterized in that: The second gripper includes a second link and a third link hinged together, and a second dielectric fiber actuator connected between the second link and the third link for controlling the centripetal or centrifugal movement of the second link; The third link is assembled on the mounting base; the second link is hinged to the first gripper. The first dielectric fiber driver is connected between the second link and the first gripper.

6. The dielectric fiber driven gripper according to claim 5, characterized in that: The tail end of the first gripper is provided with a first fiber curing hole, and the tail end of the second connecting rod is provided with a second inclined groove. The first dielectric fiber driver is distributed along the length of the second connecting rod, and one end of the first dielectric fiber driver is fixed in the first fiber curing hole, and the other end is fixed on the second inclined groove.

7. The dielectric fiber driven gripper according to claim 6, characterized in that: The middle part of the second link is hinged to the front end of the third link; The second connecting rod has a second fiber curing hole in the middle, and the third connecting rod has a third inclined groove at the tail end; The second dielectric fiber actuator is distributed along the length of the third link, and one end of the second dielectric fiber actuator is fixed in the second fiber curing hole, and the other end is fixed on the third inclined groove.

8. The dielectric fiber driven gripper according to claim 7, characterized in that: Both the second and third connecting rods are provided with through holes for weight reduction.

9. The dielectric fiber driven gripper according to any one of claims 1, 2, 4, 6-8, characterized in that: The front end of the first gripper has a flexible front section made of silicone or rubber.

10. The dielectric fiber driven gripper according to claim 9, characterized in that: The mounting base is a disc-shaped structure with several elongated holes distributed circumferentially for assembling the second gripper. The length direction of each elongated hole is consistent with the radial direction of the mounting base. The mounting base has a protrusion at the center of its top surface for clamping the moving device.

Images