An internally retractable high aspect ratio pneumatic soft gripper device

Abstract

The application discloses a high-aspect-ratio pneumatic soft gripper device capable of internal telescoping. The pneumatic soft gripper comprises a fixed table, a double-engine winding mechanism and a plurality of soft fingers. The double-engine winding mechanism is installed on the top surface of the fixed table, the root ends of the soft fingers are uniformly and circumferentially spaced apart and installed on the bottom surface of the fixed table, the soft fingers are connected to the double-engine winding mechanism through pull wires in the soft fingers and the double-engine winding mechanism, and the length of each soft finger is adjusted by the double-engine winding mechanism to realize internal telescoping, folding and unfolding and asymmetric expansion and bending actions, so that the pneumatic soft gripper can grasp different target objects. The high-aspect-ratio pneumatic soft gripper has a compact structure and strong grasping adaptability, can generate spiral winding deformation after elongation, is suitable for grasping irregular objects, and can realize self-adaptive grasping of objects of different sizes by controlling the extension length of the soft gripper.

Description

Technical Field

[0001] This invention relates to a pneumatic soft gripper device, specifically a high aspect ratio pneumatic soft gripper device that can extend and retract from the inside. Background Technology

[0002] Soft grippers, due to their flexibility and adaptability, are attracting increasing attention in scenarios such as biological sampling, object handling, and medical rehabilitation. However, current soft grippers cannot adjust their length according to the size of the object being gripped, limiting their ability to grasp objects of a limited size. Furthermore, existing soft grippers all employ opening and closing grips, limiting their ability to grasp objects with regular shapes and hindering their ability to grasp complex shapes. Therefore, a technological solution is urgently needed to overcome or at least mitigate the shortcomings of existing technologies. Summary of the Invention

[0003] To address the problems existing in the background art, the present invention provides a high aspect ratio pneumatic soft gripper device that can extend and retract from the inside. The present invention utilizes a square container and a reel-type cable working in concert to adjust its length according to the size of the object being gripped. Furthermore, through an array of soft grippers and their intertwining, it can grasp objects with uneven shapes, such as tree branches or marine corals.

[0004] The technical solution adopted in this invention is:

[0005] The high aspect ratio pneumatic soft gripper device of the present invention, which can extend and retract from the inside, includes a fixed platform, a dual-engine winding mechanism, and a number of soft fingers. The fixed platform is horizontally installed at a fixed position, the dual-engine winding mechanism is installed on the top surface of the fixed platform, and the root ends of each soft finger are evenly spaced along the circumference on the bottom surface of the fixed platform. Each soft finger is connected to the dual-engine winding mechanism and is internally connected to the dual-engine winding mechanism through a pull wire. The dual-engine winding mechanism drives each soft finger to adjust its length to perform internal extension and retraction and asymmetrical expansion and bending actions, so that the pneumatic soft gripper device can grasp different target objects.

[0006] Each of the aforementioned soft fingers is a hollow silicone rubber elastomer with a through root end. There are at least four soft fingers, which are asymmetrically distributed in radial wall thickness. The wall thickness on the back of the finger is less than that on the fingertip, and the wall thickness at the fingertip increases uniformly from the back to the fingertip. The lower end of the pull cord is connected to the inside of the fingertip. The bottom of the dual-motor winding mechanism passes through the fixed platform and connects to the root end of the soft finger. When the soft finger is inflated by the dual-motor winding mechanism, the axial elongation on the back of the finger is greater than that on the fingertip. The pneumatic soft gripper device of the soft finger bends at the center to complete the gripping action.

[0007] The cross-sectional area of ​​the hollow portion inside each of the aforementioned soft fingers in the vertical plane is greater than the cross-sectional area of ​​the solid wall portion.

[0008] The dual-engine take-up mechanism includes several dual-engine take-up units, an air distribution chamber, and an air compressor. Each dual-engine take-up unit is evenly spaced around the top surface of the fixed platform. Each dual-engine take-up unit is located directly above one of its respective soft fingers and is connected to the soft fingers via a pull wire. The air distribution chamber and the air compressor are installed at the center of the top surface of the fixed platform and are interconnected. The air distribution chamber is connected to the dual-engine take-up units via several air pipes.

[0009] Each of the aforementioned dual-motor retractors includes a square container, a drum, and a motor. The square container is mounted on the top surface of a fixed platform. An air vent is opened on the bottom surface of the square container and passes through the fixed platform. The base of a soft finger is fitted outside the air vent and connected to the square container. An air inlet is opened on the side of the square container and connected to the air distribution chamber through an air pipe. The motor body is mounted on the top surface of the fixed platform and located on the side of the square container. A support hole is also opened on the side of the square container near the motor. The drum is horizontally fitted into the support hole. One end of the drum is located outside the square container and synchronously connected to the output shaft of the motor. The other end of the drum is located inside the square container and wound around the upper end of the pull cable.

[0010] The drum has a semi-circular second connection hole at one end outside the square container, which allows the drum and the motor shaft to be detachably connected; the motor controls the rotation, locking and unlocking of the drum, thereby controlling the retraction, locking and unlocking of the cable.

[0011] The gripping method of the high aspect ratio pneumatic soft gripper device that can extend from the inside according to the present invention includes:

[0012] When the pneumatic soft gripper device is controlled, gas of different pressures is introduced into each soft finger through a dual-engine winding mechanism. Combined with the release and retraction cable, each soft finger switches between different extension states, enabling the release extension, asymmetric expansion and bending deformation, and internal retraction actions of each soft finger to adaptively grasp target objects of different sizes.

[0013] When the pneumatic soft gripper device grasps a target object, each soft finger is initially located inside a square container. The device is moved above the target object, and a release extension action is performed via a pull cable and motor, causing each soft finger to extend to a different preset length. The pull cable is then locked, and an air compressor inflates the finger to perform an asymmetrical expansion and bending deformation action, causing the finger to expand asymmetrically to bend or spiral around the target object to complete the grasp. The air compressor then deflates to release the target object. Next, the air compressor inflates the finger, and the motor tightens the pull cable to perform an internal retraction action. The inflation causes the soft finger to slightly bulge, and the pull cable pulls the finger back into the square container, ultimately completing the target object extension-grabbing-release-retraction action.

[0014] When the soft finger extends, low-pressure gas is introduced into the square container and a pull line is released, causing the soft finger to extend and lengthen from the square container. When the soft finger undergoes asymmetrical expansion and bending deformation, high-pressure gas is introduced into the square container and the pull line is locked, causing the extended part of the soft finger to undergo asymmetrical expansion and bending deformation, thus achieving a grasping function. When the soft finger retracts internally, low-pressure gas is introduced into the square container and the pull line is retracted, causing the extended soft finger to be retracted into the square container.

[0015] When the soft fingers grasp target objects of different sizes, by controlling the aspect ratio of the extended portion of the soft fingers to be less than 8:1, high-pressure gas is filled into a square container, and the extended portion of each soft finger bends towards the center of the fixed platform to grasp small and regularly shaped target objects; by controlling the aspect ratio of the extended portion of the soft fingers to be greater than 8:1, high-pressure gas is filled into a square container, and the soft fingers spiral and wrap around each other to grasp large and irregularly shaped target objects.

[0016] The beneficial effects of this invention are:

[0017] 1. The soft gripper of the present invention can achieve internally controllable extension and retraction adjustment according to the size and shape of the object being gripped. The soft fingers can smoothly transition between different lengths, thereby adapting to the gripping needs of objects of various sizes and significantly improving the versatility and flexibility of the device.

[0018] 2. This invention adopts a high aspect ratio pneumatic soft finger structure, which can achieve robust enveloping gripping of complex, irregular or multi-branched objects (such as tree branches, corals, etc.) through the coordinated bending and intertwining of multiple fingers, effectively improving the gripping stability of irregular targets.

[0019] 3. The soft finger of the present invention has a significantly reduced overall size when retracted, which can effectively reduce space occupation and facilitate installation on various carriers such as drones, robotic arms or underwater operation platforms, thereby improving system integration and application flexibility.

[0020] 4. The soft gripper of the present invention can extend to grasp objects located in deep trenches or narrow wall crevices.

[0021] In summary, the high aspect ratio pneumatic soft gripper of the present invention has a compact structure and strong gripping adaptability. It can produce spiral winding deformation after extension, making it suitable for gripping irregularly shaped objects. By controlling the extension length of the soft gripper, adaptive gripping of objects of different sizes can be achieved. Attached Figure Description

[0022] Figure 1 This is a three-dimensional structural diagram of the high aspect ratio pneumatic soft gripper device of the present invention;

[0023] Figure 2 This is a three-dimensional structural diagram of the fixing platform of the present invention;

[0024] Figure 3 This is a three-dimensional structural diagram of the square container of the present invention;

[0025] Figure 4 This is a three-dimensional structural diagram of the roll of the present invention;

[0026] Figure 5 This is a cross-sectional view of the retraction process of the pneumatic soft gripper of the present invention;

[0027] Figure 6 This is a schematic diagram of the pneumatic soft gripper of the present invention wrapping and grasping an object;

[0028] In the diagram: 10. Fixed platform; 11. First mounting hole; 12. Second mounting hole; 13. Third mounting hole; 14. Fourth mounting hole; 15. Through hole; 16. Through hole; 20. Square container; 21. First connecting hole; 22. Support hole; 23. Air outlet; 24. Air inlet; 30. Air pipe; 40. Air distribution chamber; 50. Air compressor; 60. Soft finger; 70. Drum; 71. Second connecting hole; 80. Pull cable; 90. Motor. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The technical solutions described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the technical solutions in this application without inventive effort are within the scope of protection of this application.

[0030] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0031] like Figure 1As shown, the high aspect ratio pneumatic soft gripper device of the present invention, which can extend and retract from the inside, includes a fixed platform 10, a dual-engine winding mechanism, and eight soft fingers 60 made of silicone rubber with a Shore A hardness of 30A. The fixed platform 10 is horizontally installed at a fixed position, the dual-engine winding mechanism is installed on the top surface of the fixed platform 10, and the root ends of each soft finger 60 are evenly spaced along the circumference on the bottom surface of the fixed platform 10. Each soft finger 60 is connected to the dual-engine winding mechanism and is internally connected to the dual-engine winding mechanism through a pull wire 80. The dual-engine winding mechanism drives each soft finger 60 to adjust its length to perform internal extension and retraction and asymmetric expansion and bending actions, so that the pneumatic soft gripper device can grasp different target objects.

[0032] like Figure 5 As shown, each soft finger 60 is a hollow, root-end-through silicone rubber elastomer with good elasticity and ductility. The soft fingers 60 have an asymmetrical radial wall thickness distribution, with the wall thickness on the back side of the finger being less than that on the fingertip side. The wall thickness at the fingertip of the soft finger 60 increases uniformly from the back side to the fingertip side. The lower end of the pull cord 80 is connected to the interior of the fingertip of the soft finger 60. The bottom of the dual-motor retraction mechanism passes through the fixed platform 10 and connects to the root end of the soft finger 60. When the soft finger 60 is inflated by the dual-motor retraction mechanism, the axial elongation of the back side of the finger is greater than that of the fingertip side. The pneumatic soft gripper device of the soft finger 60 bends at the center to complete the gripping action. The cross-sectional area of ​​the hollow part inside each soft finger 60 in the vertical plane is larger than that of the solid wall part, so as to facilitate retraction from the inside under the traction of the pull cord 80.

[0033] The dual-engine retractor mechanism includes several dual-engine retractors, an air distribution chamber 40, and an air compressor 50. Each dual-engine retractor is evenly spaced around the top surface of the fixed platform 10. Each dual-engine retractor is located directly above its respective soft finger 60 and is connected to the soft finger 60 via a pull cable 80. The air distribution chamber 40 and the air compressor 50 are installed at the center of the top surface of the fixed platform 10 and are interconnected. The air distribution chamber 40 is connected to the dual-engine retractors via several air pipes 30.

[0034] like Figure 3 and Figure 4As shown, each dual-motor retractor includes a square container 20, a drum 70, and a motor 90. The square container 20 is mounted on the top surface of the fixed platform 10. An air vent 23 is opened on the bottom surface of the square container 20 and passes through the fixed platform 10. The root end of the soft finger 60 is fitted outside the air vent 23 and connected to the square container 20. An air inlet 24 is opened on the side of the square container 20 and connected to the air distribution chamber 40 through an air pipe 30. The body of the motor 90 is mounted on the top surface of the fixed platform 10 and located on the side of the square container 20. A support hole 22 is also opened on the side of the square container 20 near the motor 90. The drum 70 is horizontally fitted in the support hole 22. One end of the drum 70 is located outside the square container 20 and is synchronously connected to the output shaft of the motor 90. The other end of the drum 70 is located inside the square container 20 and is wound around the upper end of the pull cable 80. The drum 70 has a semi-circular second connection hole 71 at one end outside the square container 20, which allows the drum 70 and the shaft of the motor 90 to be detachably connected; the rotation, locking and unlocking states of the drum 70 are realized by the motor 90, so as to control the retraction, locking and unlocking states of the pull cable 80.

[0035] like Figure 2 As shown, the mounting platform 10 has a first mounting hole 11 for fixing the motor bracket, on which the motor 90 is mounted. It also has a second mounting hole 12 for fixing the square container 20, a third mounting hole 13 and a fourth mounting hole 14 for fixing the air compressor 50 and the air distribution chamber 40, a through hole 15 for the air outlet 23 of the square container 20 to pass through, and a reserved through hole 16 for connecting to an external control unit or peripheral device. The bottom side of the square container 20 has a first connection hole 21 for connecting to the mounting platform 10.

[0036] The grasping method of the internally retractable high aspect ratio pneumatic soft gripper device of the present invention is as follows:

[0037] During control, the individual soft fingers 60 of the pneumatic soft gripper are supplied with gas of different pressures through a dual-motor retraction mechanism. Combined with the retraction cable 80, this allows the soft fingers 60 to switch between different extension states. This enables the release extension, asymmetric expansion and bending deformation, and internal retraction of the soft fingers 60, allowing them to adaptively grasp target objects of different sizes. The soft fingers 60 can automatically adjust their extension length according to the size and shape of the object being grasped, achieving flexible gripping.

[0038] When the pneumatic soft gripper device grasps a target object, each soft finger 60 is initially located inside the square container 20, resulting in a compact and small overall structure. The device is then moved above the target object, and a release extension action is performed via the pull cable 80 and motor 90, causing each soft finger 60 to extend to a different preset length. The pull cable 80 is then locked, and air is inflated by the air compressor 50 to perform an asymmetrical expansion and bending deformation action, causing each soft finger 60 to expand asymmetrically to bend or spiral around the target object to complete the grasp. Air is then released by deflating the air compressor 50 to release the target object. Next, air is inflated again by the air compressor 50, and the pull cable 80 is tightened by the motor 90 to perform an internal retraction action. The inflation causes the soft fingers 60 to slightly bulge, and the pull cable 80 pulls the soft fingers 60 back into the square container 20, ultimately completing the target object extension-grabbing-release-retraction action.

[0039] When the soft finger 60 extends, low-pressure gas (less than 15 kPa) is introduced into the square container 20 and the pull line 80 is released, causing the soft finger 60 to extend and lengthen from the square container 20. When the soft finger 60 undergoes asymmetrical expansion and bending deformation, high-pressure gas (greater than 30 kPa) is introduced into the square container 20 and the pull line 80 is locked, causing the extended portion of the soft finger 60 to undergo asymmetrical expansion and bending deformation, achieving a grasping function. When the soft finger 60 retracts internally, low-pressure gas (less than 15 kPa) is introduced into the square container and the pull line 80 is retracted, causing the extended soft finger 60 to be retracted into the square container 20. By selecting low-pressure or high-pressure gas for the square container 20 and coordinating with the control of the pull line 80's extension and lengthening, asymmetrical expansion and bending, and internal retraction actions, the soft finger 60 can achieve these actions.

[0040] When the soft fingers 60 grasp target objects of different sizes, by controlling the aspect ratio of the extended portion of the soft fingers 60 to be less than 8:1, high-pressure gas greater than 30 kPa is filled into the square container 20, and the extended portion of each soft finger 60 bends towards the center of the fixed platform 10 to grasp small and regularly shaped target objects, such as square or cylindrical objects; by controlling the aspect ratio of the extended portion of the soft fingers 60 to be greater than 8:1, high-pressure gas greater than 30 kPa is filled into the square container 20, and each soft finger 60 spirals and wraps around to grasp large and irregularly shaped target objects such as tree branches and coral.

[0041] In its initial state, the device of this invention has a 15 mm diameter soft finger 60 completely retracted inside the square container 20 to reduce its volume. When performing a grasping task, the system coordinates with the motor 90 to release the pull cord 80 and introduce 15 kPa low-pressure gas into the square container 20, driving the soft finger 60 to extend as needed. When the target is a ping-pong ball with a diameter of approximately 40 mm, the soft finger 60 is extended to 60 mm, at which point the aspect ratio of the extended portion is 4:1. Subsequently, the pull cord 80 is locked and 50 kPa high-pressure gas is introduced, inducing the soft finger 60 to undergo asymmetrical expansion and bend towards the center of the fixed platform 10 to form a cage-like enveloping grasp. When the target is an irregular tree branch, the soft finger 60 is extended to 150 mm, at which point the aspect ratio is 10:1. The pull cord 80 is then locked and 50 kPa high-pressure gas is introduced. High-pressure gas at kPa causes the soft finger 60 to spatially buckle due to its large aspect ratio, thus tightly wrapping around the target in a spiral shape. After the task is completed, the object is released by depressurization. Finally, a weak airflow of about 10 kPa is introduced again to keep the soft finger 60 slightly bulging to prevent it from folding or buckling. At the same time, the motor 90 tightens the pull line at a speed of 15 mm / s, smoothly and completely dragging and retrieving the soft finger 60 into the square container 20, completing the entire process control from extension, adaptive grasping, release to retrieval. Figure 6 As shown, when the aspect ratio of the extended part of the soft finger 60 is 10:1, it can wrap around and grasp large, irregularly shaped objects such as winnowing baskets and tree branches.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A high aspect ratio pneumatic soft gripper device that can extend and retract from the inside, characterized in that: The device includes a fixed platform (10), a dual-engine winding mechanism, and several soft fingers (60). The fixed platform (10) is horizontally installed at a fixed position. The dual-engine winding mechanism is installed on the top surface of the fixed platform (10). The root ends of each soft finger (60) are evenly spaced along the circumference on the bottom surface of the fixed platform (10). Each soft finger (60) is connected to the dual-engine winding mechanism and is internally connected to the dual-engine winding mechanism via a pull wire (80). The dual-engine winding mechanism drives each soft finger (60) to adjust its length to perform internal telescopic extension and retraction as well as asymmetrical expansion and bending actions, so that the pneumatic soft gripper device can grasp different target objects. Each of the aforementioned soft fingers (60) is a hollow silicone rubber elastomer with a through root end. The soft fingers (60) have an asymmetrical distribution in radial wall thickness. The wall thickness of the back of the soft finger (60) is less than that of the finger pad. The wall thickness at the fingertip of the soft finger (60) increases uniformly from the back of the finger to the finger pad. The lower end of the pull wire (80) is connected to the inside of the fingertip of the soft finger (60). The bottom of the dual-motor winding mechanism passes through the fixed platform (10) and connects to the root end of the soft finger (60). When the soft finger (60) is inflated by the dual-motor winding mechanism, the axial elongation of the back of the finger is greater than that of the finger pad. The pneumatic soft gripper device of the soft finger (60) bends in the center to complete the gripping action.

2. The high aspect ratio pneumatic soft gripper device that can extend from the inside according to claim 1, characterized in that: The cross-sectional area of ​​the hollow portion inside each of the aforementioned soft fingers (60) in the vertical plane is greater than the cross-sectional area of ​​the solid wall portion.

3. The high aspect ratio pneumatic soft gripper device that can extend from the inside according to claim 1, characterized in that: The dual-engine winding mechanism includes several dual-engine winding units, an air distribution chamber (40), and an air compressor (50). Each dual-engine winding unit is evenly spaced around the top surface of the fixed platform (10). Each dual-engine winding unit is located directly above one of its own soft fingers (60) and is connected to the soft fingers (60) via a pull wire (80). The air distribution chamber (40) and the air compressor (50) are installed at the center of the top surface of the fixed platform (10) and are connected to each other. The air distribution chamber (40) is connected to the dual-engine winding units via several air pipes (30).

4. The high aspect ratio pneumatic soft gripper device that can extend from the inside according to claim 3, characterized in that: Each of the dual-engine retractors includes a square container (20), a drum (70), and a motor (90). The square container (20) is mounted on the top surface of the fixed platform (10). An air vent (23) is opened on the bottom surface of the square container (20) and passes through the fixed platform (10). The root end of the soft finger (60) is fitted outside the air vent (23) and connected to the square container (20). An air inlet (24) is opened on the side of the square container (20) and connected to the air distribution chamber (40) through an air pipe (30). The motor (90) is mounted on the top surface of the fixed platform (10) and located on the side of the square container (20). The square container (20) is also provided with a support hole (22) on the side near the motor (90). The drum (70) is horizontally fitted in the support hole (22). One end of the drum (70) is located outside the square container (20) and is synchronously connected to the output shaft of the motor (90). The other end of the drum (70) is located inside the square container (20) and is wound around the upper end of the pull wire (80).

5. The high aspect ratio pneumatic soft gripper device that can extend from the inside according to claim 4, characterized in that: The drum (70) is provided with a semi-circular second connection hole (71) at one end outside the square container (20), so that the drum (70) and the shaft of the motor (90) can be detachably connected; the rotation, locking and unlocking states of the drum (70) are realized by the motor (90) to control the retraction, locking and unlocking states of the pull line (80).

6. The grasping method of the internally retractable high aspect ratio pneumatic soft gripper device according to any one of claims 1-5, characterized in that, include: When the pneumatic soft gripper device is controlled, gas of different pressures is introduced into each soft finger (60) through the dual-motor winding mechanism, and combined with the retraction and release cable (80), the soft fingers (60) switch between different extension states, so that the release extension, asymmetric expansion bending deformation and internal retraction of each soft finger (60) can adaptively grasp target objects of different sizes.

7. The grasping method of the internally retractable high aspect ratio pneumatic soft gripper device according to claim 6, characterized in that: When the pneumatic soft gripper device grasps the target object, each soft finger (60) is initially located inside the square container (20). The pneumatic soft gripper device is moved above the target object to be grasped. The release extension action is performed by the pull line (80) and the motor (90), so that each soft finger (60) is extended to a different preset length. Then the pull line (80) is locked and the air compressor (50) is used to inflate the device to perform an asymmetric expansion bending deformation action, so that each soft finger (60) undergoes asymmetric expansion to bend or spiral around the target object to complete the grasp. The air compressor (50) is used to release the target object. Then the air compressor (50) is used to inflate the device and the motor (90) is used to tighten the pull line (80) to perform an internal retraction action. The pull line (80) is used to pull the soft finger (60) back into the square container (20), and finally the target object extension-grabbing-release-retraction action is completed.

8. The grasping method of the internally retractable high aspect ratio pneumatic soft gripper device according to claim 7, characterized in that: When the soft finger (60) performs a release and extension action, low-pressure gas is introduced into the square container (20) and the pull line (80) is released, and the soft finger (60) is released and extended from the square container (20) and becomes longer; when the soft finger (60) performs an asymmetric expansion and bending deformation action, high-pressure gas is introduced into the square container (20) and the pull line (80) is locked, and the extended part of the soft finger (60) produces an asymmetric expansion and bending deformation to achieve the grasping function; when the soft finger (60) performs an internal retraction action, low-pressure gas is introduced into the square container and the pull line (80) is retracted, and the extended soft finger (60) is retracted into the square container (20).

9. The grasping method of the internally retractable high aspect ratio pneumatic soft gripper device according to claim 7, characterized in that: When the soft fingers (60) grasp target objects of different sizes, by controlling the aspect ratio of the extended part of the soft fingers (60) to be less than 8:1, high-pressure gas is filled into the square container (20), and the extended part of each soft finger (60) bends towards the center of the fixed platform (10) to grasp small and regularly shaped target objects; by controlling the aspect ratio of the extended part of the soft fingers (60) to be greater than 8:1, high-pressure gas is filled into the square container (20), and each soft finger (60) generates a spiral winding to grasp large and irregularly shaped target objects.

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