Nested soft actuator, manipulator and soft robot

Abstract

The invention discloses a nested type soft actuator, a manipulator and a soft robot, and relates to the field of robots. The nested type soft actuator comprises an air bag and a limiting shell arranged at one end and the outer side of the air bag in a sleeving mode, a plurality of grid holes extending in the width direction of the limiting shell are formed in the top face of the limiting shell and arranged at intervals in the length direction of the limiting shell, and the two ends of each grid hole extend to the bottoms of the two sides of the limiting shell respectively. According to the nested type soft actuator, the manipulator and the soft robot, the limiting shell is arranged to wrap one end and the outer wall of the air bag, and the grating holes are formed in the outer wall of the limiting shell, so that the air bag can be limited through the limiting shell in the air inflation process, and the air bag is prevented from extending in the radial direction and the axial direction; and the change of the air in the air bag is only used for controlling the bending action, so that the relation between the air inflation amount and the bending amount of the air bag is clear, the relation between the air inflation amount and the grabbing extrusion force is easy to determine, and the control difficulty of the soft actuator is reduced.

Description

Technical Field

[0001] The invention belongs to the field of robots, and in particular relates to a nested soft actuator, a manipulator and a soft robot. Background Art

[0002] The soft robot actuator achieves the bending movement of the manipulator by inflating and deflating the airbag. Therefore, when the manipulator performs a grasping action, it is necessary to consider controlling the bending degree and force of the actuator.

[0003] When the actuator of an existing soft robot performs a grasping action, the airbag will extend in both the radial and axial directions after being inflated. The extended space increases the requirements for the inflation volume and control. Specifically, when the manipulator performs a grasping action, the airbag bends to generate a squeezing force on the grasped object. However, during the grasping action of the manipulator on the grasped object, the gas content in the airbag will be inflated or deflated in real time due to the weight of the grasped object, the surface smoothness or the allowable grasping squeezing force, etc. During the inflation process, the airbag will extend in the radial and axial directions, resulting in changes in the gas in the airbag. It is not easy to determine the relationship between the gas volume and the grasping squeezing force, which increases the difficulty of control. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a nested soft actuator, a manipulator and a soft robot, which can limit the airbag in the radial and axial directions through a limiting shell during the inflation process of the airbag, so that the change of the gas in the airbag is only used to control the bending action, ensuring that the relationship between the airbag inflation amount and the bending amount is clear, and the relationship between the gas inflation amount and the grasping extrusion force is easy to determine, thereby reducing the control difficulty of the soft actuator.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: A nested soft actuator comprises an airbag and a limiting shell sleeved on one end and the outside of the airbag, the top surface of the limiting shell is provided with a plurality of grid holes extending along its width direction, the plurality of grid holes are arranged at intervals along the length direction of the limiting shell, and the two ends of the grid holes extend to the bottom of both sides of the limiting shell respectively.

[0006] Preferably, the limiting shell includes a bottom plate with its top pressing against the bottom of the airbag, a grabbing portion connected to one end of the bottom plate, and a plurality of arc-shaped grid plates connected to the top surface of the bottom plate, with grid holes formed between two adjacent grid plates.

[0007] Preferably, at least one grid plate is one of a current sensor, an inductive sensor and a capacitive sensor.

[0008] Preferably, the airbag and the grid plate are made of silicone rubber; and / or the bottom plate is made of vulcanized rubber.

[0009] Preferably, the end surface of the gripping portion is one of a convex spherical surface, a concave spherical surface, a vertical surface or an inclined surface.

[0010] Preferably, the thickness of the bottom plate d 0 is determined according to the following formula: ;in, d is the initial thickness of the base plate; δ and γ To adjust the parameters; P is the maximum inflation volume of the airbag; B It is the minimum bending degree of the sleeve-type soft actuator.

[0011] Preferably, the maximum inflation volume of the airbag P Determined by the following formula: ; in, P 0 is the initial air content of the airbag; a is the fitting parameter; F The required grabbing squeeze force.

[0012] Preferably, the minimum bending degree of the nested soft actuator is B Determined by the following formula: ; in, B 0 is the initial bending degree of the nested soft actuator; b is the fitting parameter; F The required grabbing squeeze force.

[0013] The present invention also provides a manipulator, which includes a connecting member, a plurality of sliding mechanisms arranged at intervals along the circumference of the connecting member, and fixed clamps connected to the sliding mechanisms one by one. The sliding mechanisms can be rotatably connected to the connecting member in a direction approaching or moving away from the connecting member, and the fixed clamps can be connected to the corresponding sliding mechanisms in a radially movable manner along the connecting member. Each fixed clamp is connected to one of the above-mentioned nested soft actuators.

[0014] The present invention can achieve the following beneficial effects: The nested soft actuator provided by the present invention comprises an airbag and a limiting shell sleeved on one end and the outside of the airbag, the top surface of the limiting shell is provided with a plurality of grid holes extending along the width direction thereof, the plurality of grid holes are arranged at intervals along the length direction of the limiting shell, and the two ends of the grid holes extend to the bottom of both sides of the limiting shell respectively. The nested soft actuator, manipulator and soft robot provided by the present invention are provided with a limiting shell to wrap one end and the outer wall of the airbag, and a grid hole is provided on the outer wall of the limiting shell, so that the limiting shell can be used to limit the airbag during the inflation process and avoid the radial and axial extension of the airbag, so that the change of the gas in the airbag is only used to control the bending action, so as to ensure that the relationship between the inflation amount of the airbag and the bending amount is clear, and the relationship between the gas inflation amount and the grasping extrusion force is easy to determine, thereby reducing the control difficulty of the soft actuator. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further described below in conjunction with the accompanying drawings and embodiments: Figure 1 A schematic structural diagram of a nested soft actuator from a first perspective provided by an embodiment of the present invention; Figure 2 A schematic cross-sectional view of a nested soft actuator provided in an embodiment of the present invention; Figure 3 A schematic structural diagram of a nested soft actuator from a second perspective provided by an embodiment of the present invention; Figure 4 A schematic structural diagram of a nested soft actuator from a third perspective provided by an embodiment of the present invention; Figure 5 A schematic diagram of the structure of the nested soft actuator provided by an embodiment of the present invention when the gripping portion is a convex spherical surface; Figure 6 A schematic diagram of the structure of the nested soft actuator provided by an embodiment of the present invention when the gripping portion is a concave spherical surface; Figure 7 A schematic diagram of the structure of the nested soft actuator provided by an embodiment of the present invention when the gripping portion is a vertical surface; Figure 8 A schematic diagram of the structure of the nested soft actuator provided in an embodiment of the present invention when the gripping portion is a 30° inclined surface; Fig. 9 A schematic diagram of the structure of the nested soft actuator provided by the embodiment of the present invention when the gripping portion is a 45° inclined surface; Fig.10 A schematic diagram of the structure of the nested soft actuator provided in an embodiment of the present invention when the gripping portion is a 60° inclined surface; Fig.11 A schematic diagram of the structure of a manipulator provided in an embodiment of the present invention.

[0016] In the figure: 100, airbag; 200, limiting shell; 210, grid hole; 220, bottom plate; 230, grabbing part; 240, grid plate; 250, accommodating groove; 300, connecting piece; 310, connecting seat; 320, connecting hole; 400, sliding mechanism; 410, adjusting bracket; 420, sliding sleeve; 430, locking notch; 440, locking hole; 450, bolt; 460, sleeve bracket; 470, sleeve connecting hole; 500, fixing fixture; 510, adjusting disk; 520, connecting shaft; 530, adjusting hole. DETAILED DESCRIPTION

[0017] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, an embodiment of the present invention provides a nested soft actuator, which is used to solve the problem that the brake of the existing soft robot extends in the radial and axial directions of the airbag after the airbag is inflated during the grasping action, affecting the control accuracy. The nested soft actuator includes an airbag 100 and a limiting shell 200 sleeved on one end and the outside of the airbag 100. The limiting shell 200 includes a bottom plate 220 with a top pressing against the bottom of the airbag 100, a grasping portion 230 connected to one end of the bottom plate 220, and sixteen ends respectively connected to the bottom plate 220. 0 arc-shaped grid plates 240 on both sides of the top surface, one end of the grabbing portion 230 is provided with a receiving groove 250 for receiving one end of the airbag 100, grid holes 210 are respectively formed between two adjacent grid plates 240 and between the grid plate 240 and the grabbing portion 230, sixteen grid holes 210 are arranged at intervals along the length direction of the limiting shell 200, and both ends of the grid holes 210 extend to the bottom of both sides of the limiting shell 200 respectively, the airbag 100 and the grid plate 240 are made of silicone rubber, and the grabbing portion 230 and the bottom plate 220 are made of vulcanized rubber.

[0018] The nested soft actuator provided in the embodiment of the present invention is limited by fixing a limiting shell 200 on one end and the outer side of the airbag 100, which can prevent the airbag 100 from extending in the radial and axial directions during the inflation and deflation of the airbag 100, and ensure that the volume change of the gas in the airbag 100 is only used to control the bending action of the airbag 100 and the limiting shell 200, so that the relationship between the amount of gas inflated and deflated by the airbag 100 and the bending amount of the airbag 100 is clear, and the relationship between the amount of gas inflated and deflated by the airbag 100 and the gripping and squeezing force of the nested soft actuator is easy to determine, thereby reducing the control difficulty of the nested soft actuator.

[0019] Optionally, the airbag 100 is connected to an air outlet pipe and an air inlet pipe, which are respectively connected to an air suction device and an air supply device, so that the bending ability of the airbag 100 can be adjusted by changing the amount of gas in the airbag 100 through the air suction device and the air supply device, so as to realize the pressure applied to the grasping object when the nested soft actuator adjusts the grasping action.

[0020] Optionally, the airbag 100 is cylindrical, and sixteen arc-shaped grid plates 240 are connected to the top surface of the bottom plate 220. When the actuator is subjected to external force during operation, the grid plates 240 bend to achieve a grasping action. The hardness of the limiting shell 200 is greater than the hardness of the airbag 100 to protect the airbag 100. For example, the main parts of the airbag 100 and the limiting shell 200 are made of silicone rubber with different material constants, and the bottom plate 220 of the limiting shell 200 uses relatively hard and difficult to deform vulcanized rubber. Alternatively, the airbag 100 uses silicone rubber, and the limiting shell 200 uses other materials harder than silicone rubber.

[0021] Optionally, a gripping portion 230 is provided at one end of the limiting housing 200, and an end surface of the gripping portion 230 is configured as a convex spherical surface, a concave spherical surface, a vertical surface or an inclined surface to correspond to different gripping requirements.

[0022] In the nested soft actuator provided by the embodiment of the present invention, the cross-section of the airbag 100 located inside the limiting shell 200 is completely consistent under the coronal plane, and a limiting shell 200 with weaker deformation ability is fixedly sleeved on the outer surface of the airbag 100, so as to limit the radial and axial expansion outside the airbag 100. The bending ability of the nested soft actuator is mainly affected by the deformation ability of the material between the limiting shell 200 and the airbag 100, the spacing and thickness between the grid plates 240, the shape of the gripping part 230, the thickness of the bottom plate 220, etc. The function of the grid plate 240 is equivalent to the limiting line in the corrugated actuator, which has a limiting effect on the radial deformation of the soft actuator. Generally, the increase in the thickness of the grid plate 240 will enhance the effect of this limitation. In order to prevent the appearance of the soft actuator from changing too much, the thickness t0 of the grid plate 240 can be set to a range of 1mm-5mm.

[0023] Considering the effect of the thickness d0 of the bottom plate 220 at the bottom of the limiting shell 200 on the bending performance of the nested soft actuator, the bottom plate 220 is used to limit the elongation of the actuator in the axial direction, so as to achieve the bending effect. Under the same air pressure, as the thickness d0 of the bottom plate 220 increases, the bending angle of the soft actuator is greatly reduced, and after 4mm, the finger cannot be fully flexed. However, when the thickness d0 of the bottom plate 220 is too small, the bottom plate 220 can no longer resist the deformation caused by the air pressure, so that the bending angle decreases instead. If the pressure is continued, the bending angle of the soft actuator will not increase significantly, but the airbag 100 will expand radially until the material fails and causes the airbag 100 to burst. Based on the current simulation results, when the material strength is sufficient and can limit the axial elongation of the soft actuator, the thickness of the bottom plate 220 of the limiting shell 200 should be as small as possible.

[0024] Therefore, in this embodiment, when determining the thickness d0 of the bottom plate 220, the maximum inflation amount allowed by the airbag 100 is considered. P and the minimum bending of the brake B Two factors; optional: ; Maximum inflation volume of airbag 100 P Determined by the following formula: ; Minimum bending degree of nested soft actuators B Determined by the following formula: ; in, d is the initial thickness of the base plate; δ and γ To adjust the parameters; P is the maximum inflation volume of the airbag 100; P 0 is the initial air content of the airbag; a is the fitting parameter; F The required grasping and squeezing force is related to the surface and weight of the grasped object; B is the minimum bending degree of the nested soft actuator, B 0 is the initial bending degree of the nested soft actuator, which can be represented by the maximum bending angle of the nested soft actuator when grasping an object.

[0025] When the object to be grasped is smooth or heavy, it is necessary to increase the amount of inflation to increase the grasping squeezing force. At this time, adjust the parameters δis a positive number, the thickness d0 of the bottom plate 220 increases to prevent the radial direction of the airbag 100 from changing; on the contrary, when the grasping object is rough, the surface is easily deformed, or the weight is small, it is necessary to reduce the grasping extrusion force by reducing the gas volume. At this time, the adjustment parameter δ is a negative number, the thickness d0 of the bottom plate 220 is reduced, thereby improving the bending flexibility while ensuring the function of limiting the airbag 100.

[0026] like Figure 2 As shown, from the structure of the limit housing 200, it can be known that the width d2 of the grid plate 240 and the width d3 of the grid hole 210 between two adjacent grid plates 240 are a pair of interrelated parameters. The width d2 of the grid plate 240 and the width d3 of the grid hole 210 cause the stiffness of the actuator in the axial direction to change, thereby causing bending when pressurized. The wider the width of the grid plate 240, the greater the restriction on radial deformation, and the more difficult it is for the actuator to bend. However, the local use of a large-width grid plate 240 can form a large rotation angle similar to that of a human hand joint, and can be specially matched according to the finger size of each patient to achieve better results.

[0027] The increase in the width d3 of the grid hole 210 will also make it difficult for the actuator to deform. Considering the limit, when the width d3 of the grid hole 210 continues to increase to the limit, it is equivalent to having no grid plate 240 above the soft actuator, and thus the soft actuator cannot deform. Figure 2 As shown, through finite element analysis, it can be obtained that when the width d3 of the grid hole 210 is 2 mm and 3 mm, the final result is that the internal airbag 100 protrudes in multiple places and the grid plate 240 is broken.

[0028] The gripping portion 230 at the end of the limiting housing 200 includes three basic parameters and a specific structure, including the gripping portion 230 structure length d q , the depth d4 of the airbag 100 embedded in the receiving groove 250 and the connection height d5 of the grid plate 240, as well as the end surface structure shape of the gripping portion 230. The front end structure of the vertical surface of the gripping portion 230 is divided into a vertical surface, a convex 1 / 4 spherical surface structure (hereinafter referred to as a convex spherical surface structure), a concave 1 / 4 spherical surface structure (hereinafter referred to as a concave spherical surface structure) and an inclined surface structure according to the amount of resection and the resection method. The inclined surface structure includes a beveled 30°, 45° and 60° structure. Different end surface structures of the gripping portion 230 are as follows Figures 5 to 10 shown.

[0029] Among them, the vertical surface structure has the greatest impedance to air pressure, and its bending angle is only 192° at the same 40kPa. The front end structure of the 60° beveled surface performs generally in terms of bending angle, and its bending angle is about 180°. However, the performance in front end pressure is obvious. The front end pressure under the same conditions is 1.45N, and it is 1.22N when it is greater than 45°. Under the same air pressure, greater fingertip pressure means greater grasping force, which is more suitable for grasping by soft robotic arms. At the same time, although the front end structure of the 30° beveled surface can meet the angle requirements during the grasping process, its front end does not show a retracted posture when bending. Because of the angle selection, in order to ensure the bevel angle of 30°, the front end length d of the model used in the simulation is q In fact, it has exceeded 20mm. Compared with the other structures, it occupies more of the airbag. It is worth mentioning that the bevel angle of the 30° bevel is more sensitive to changes in air pressure, that is, during the initial pressurization, the angle rises faster with the change in pressure. The rate of change is slow only when the pressure is increased by 35-40kPa, which also means that a smaller pressure can bring about a larger pressure change. The front-end structure of the 45° bevel performs best, and its bending angle has reached 260°, which fully meets the robot's needs for angle grasping. Although the angle changes slowly during the final pressurization, considering the actual pressurization speed of the air pump, this structure is still the best front-end structure.

[0030] In this embodiment, the brake is optimized based on the grasping object, and can be used for grasping batches of objects, or for grasping objects of relatively fixed models and sizes. The brake is optimized so that after the optimized brake is used in the robotic arm, it can better grasp objects of the same model and size in batches or repeatedly.

[0031] Example 2 like Fig.11 As shown, an embodiment of the present invention further provides a manipulator, which includes a connecting member 300, three sliding mechanisms 400, and three fixing fixtures 500 corresponding to the sliding mechanisms 400. The sliding mechanisms 400 can be connected to the connecting member 300 by rotation in a direction close to or away from the connecting member 300, and the fixing fixtures 500 can be connected to the sliding mechanisms 400 by radial movement of the connecting member 300. The three sliding mechanisms 400 are arranged at intervals along the circumference of the connecting member 300, and each fixing fixture 500 is used to connect a nested soft actuator in Example 1. Optionally, the number of nested soft actuators and corresponding sliding mechanisms 400 and fixing fixtures 500 connected to the manipulator can also be set to two, three, four or even more.

[0032] The sliding mechanism 400 includes an adjusting bracket 410 hinged to the connecting member 300 at one end and a sliding sleeve 420 slidably mounted on the adjusting bracket 410. The adjusting bracket 410 is provided with five locking slots 430 spaced apart along its length direction. The sliding sleeve 420 is provided with two locking holes 440 corresponding to the locking slots 430. After the sliding sleeve 420 slides along the adjusting bracket 410 until the locking holes 440 are aligned with the locking slots 430, a bolt 450 is used to pass through the locking holes 440 to connect the locking slots 430 to adjustably fix the adjusting bracket 410 and the sliding sleeve 420, thereby adjusting the distance between the nested soft actuator and the connecting member 300. A sleeve bracket 460 is connected to the bottom of the sliding sleeve 420, and a sleeve connecting hole 470 is provided on the sleeve bracket 460.

[0033] The connecting member 300 is provided with three connecting seats 310 arranged at intervals along the circumferential direction. The three connecting seats 310 are respectively hinged to the adjustment brackets 410 of the three sliding mechanisms 400 in a one-to-one correspondence. Each connecting seat 310 is provided with three connecting holes 320 arranged at intervals along the circumferential direction. The adjusting bracket 410 is provided with bolt holes corresponding to the three connecting holes 320 (blocked and not shown in the figure). When the adjusting bracket 410 rotates in a direction approaching or away from the connecting member 300, the bolt hole is aligned with one of the three corresponding connecting holes 320 so that the bolt 450 passes through the bolt hole and the corresponding connecting hole 320 for connection.

[0034] Each fixing clamp 500 is connected to an adjusting disk 510, the center of which is hinged to the corresponding sleeve bracket 460 through a connecting shaft 520. The adjusting disk 510 is provided with eight adjusting holes 530 arranged at intervals along its circumference. When the adjusting disk 510 rotates, the sleeve connecting hole 470 and one of the eight adjusting holes 530 are aligned to allow the bolt 450 to pass through the sleeve connecting hole 470 and the corresponding adjusting hole 530 for connection.

[0035] The manipulator provided by the embodiment of the present invention connects three sliding mechanisms 400 and fixed clamps 500 corresponding to the sliding mechanisms 400 by setting a connecting piece 300. The sliding mechanism 400 can rotate in a direction close to or away from the connecting piece 300, and the fixed clamp 500 can move radially along the connecting piece 300 and can rotate in a direction close to or away from the connecting piece 300, so that it is convenient for the operator to adjust the position of the nested soft actuator connected to the fixed clamp 500 relative to the connecting piece 300, and use the nested soft actuators connected to each fixed clamp 500 to rotate the clamped object; specifically, The professional can remove the bolt 450 from the bolt hole and the corresponding connection hole 320, then rotate the adjustment bracket 410 relative to the corresponding hinged connection seat 310 to a preset angle, so that the bolt hole on the adjustment bracket 410 is realigned with the connection hole 320 on one connection seat 310, and then re-pass the bolt 450 through the bolt hole and the corresponding connection hole 320 to connect and fix, and then adjust the angle of the adjustment bracket 410 and the hinged corresponding connection seat 310 and re-fix, so as to adjust the angle between the connection member 300 and the three sliding mechanisms 400; at the same time, remove the bolt 450 from the locking hole 440 The locking notch 430 is connected to release the connection between the adjustment bracket 410 and the sliding sleeve 420, and the sliding sleeve 420 which is slidably mounted on the adjustment bracket 410 is adjusted to a position until the sliding sleeve 420 is adjusted to a preset position, and the two locking holes 440 on the sliding sleeve 420 are realigned with the two locking notches 430 on the adjustment bracket 410, and the bolt 450 is passed through the locking hole 440 to connect the locking notch 430 to fix the adjustment bracket 410 and the sliding sleeve 420, thereby adjusting the radial distance between the connecting member 300 and the fixing fixture 500; in addition, the bolt 450 can also be taken out. The sleeve connecting hole 470 and the corresponding adjustment hole 530 are disconnected, and the rotating adjustment disk 510 drives the fixing fixture 500 and the nested soft actuator to rotate around the connecting shaft 520 until the fixing fixture 500 and the nested soft actuator rotate to a preset angle, and an adjustment hole 530 on the adjustment disk 510 is realigned with the sleeve connecting hole 470, and the bolt 450 is passed through the sleeve connecting hole 470 and the corresponding adjustment hole 530 again to connect the sleeve bracket 460 and the fixing fixture 500, so as to adjust the angle between the fixing fixture 500 and the nested soft actuator and the corresponding sliding mechanism 400.

[0036] An embodiment of the present invention further provides a soft robot, which includes the above-mentioned manipulator.

[0037] The above embodiments are only preferred technical solutions of the present invention and should not be regarded as limiting the present invention. The protection scope of the present invention shall be the technical solutions recorded in the claims, including equivalent replacement solutions of the technical features in the technical solutions recorded in the claims. That is, equivalent replacement improvements within this scope are also within the protection scope of the present invention.

Claims

1. A nested soft actuator, characterized in that: The invention comprises an airbag (100) and a limiting shell (200) sleeved on one end and the outside of the airbag (100), wherein the top surface of the limiting shell (200) is provided with a plurality of grid holes (210) extending along the width direction thereof, the plurality of grid holes (210) are arranged at intervals along the length direction of the limiting shell (200), and the two ends of the grid holes (210) respectively extend to the bottom of two sides of the limiting shell (200).

2. The nested soft actuator according to claim 1, characterized in that: The limiting housing (200) comprises a bottom plate (220) whose top is pressed against the bottom of the airbag (100), a gripping portion (230) connected to one end of the bottom plate (220), and a plurality of arc-shaped grid plates (240) connected to the top surface of the bottom plate (220), wherein the grid holes (210) are formed between two adjacent grid plates (240).

3. The nested soft actuator according to claim 2, characterized in that: At least one of the grid plates (240) is a current sensor, an inductance sensor, and a capacitance sensor.

4. The nested soft actuator according to claim 2, characterized in that: The airbag (100) and the grid plate (240) are made of silicone rubber; And / or, the bottom plate (220) is vulcanized rubber.

5. The nested soft actuator according to claim 2, characterized in that: The end surface of the grasping portion (230) is one of a convex spherical surface, a concave spherical surface, a vertical surface or an inclined surface.

6. The nested soft actuator according to claim 2, characterized in that: The thickness of the bottom plate (220) d 0 is determined using the following formula: ; in, d is the initial thickness of the base plate; δ and γ To adjust the parameters; P is the maximum inflation volume of the airbag (100); B It is the minimum bending degree of the sleeve-type soft actuator.

7. The nested soft actuator according to claim 6, characterized in that: The maximum inflation volume of the airbag (100) P Determined by the following formula: ； in, P 0 is the initial air content of the airbag; a is the fitting parameter; F The required grabbing squeeze force.

8. The nested soft actuator according to claim 6, characterized in that: Minimum bending degree of the nested soft actuator B Determined by the following formula: ； in, B 0 is the initial bending degree of the nested soft actuator; b is the fitting parameter; F The required grabbing squeeze force.

9. A robot, characterized in that: It includes a connecting member, a plurality of sliding mechanisms arranged at intervals along the circumference of the connecting member, and a fixing clamp connected to the sliding mechanisms one by one. The sliding mechanism can be rotatably connected to the connecting member in a direction approaching or away from the connecting member, and the fixing clamp can be connected to the corresponding sliding mechanism in a radially movable manner along the connecting member. Each fixing clamp is connected to a nested soft actuator as described in any one of claims 1 to 8.

10. A soft robot, characterized in that: It comprises the robot as claimed in claim 9.

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