A multi-mode soft robot based on bistable structures and methods of use thereof

Abstract

The application provides a kind of multi-mode soft robot based on bistable structure and its use method, belong to soft robot technical field.The application has two working modes of quick grabbing and peristaltic crawling.The structure is as follows: the lower elastic plate is fixed in the groove of the connecting base, the upper and lower elastic plates are connected by symmetric hinges, and the upper elastic plate and the top plate are also connected by rotary hinges, and the elastic plate-hinge structure is uniformly provided with four groups along the circumference.In the quick grabbing working mode, the top plate moves down under pressure, and when the force exceeds the energy threshold, the robot can quickly jump from the first stable state to the second stable state and capture the object, and the actuating air bag is inflated to release the object and restore the initial state.In the peristaltic crawling working mode, the robot takes the second stable state as the initial state, and the unilateral actuating air bag is repeatedly inflated and deflated, so that the robot advances in the corresponding direction.The application has two working modes of quick grabbing and peristaltic crawling, which expands the potential application value of soft robot.

Description

Technical Field

[0001] The present invention belongs to the technical field of soft robots and relates to a multi-mode soft robot based on a bistable structure and a method for using the same. Background Art

[0002] Soft robots represent a new class of robotics technology with remarkable structural flexibility and environmental adaptability. By leveraging their material and structural properties, soft robots are able to perform a variety of complex tasks in unstructured environments, such as environmental sensing, object manipulation, and human-robot interaction. However, current soft robots often adopt relatively simple structural designs, such as a single chamber or a relatively limited multi-chamber system. This structural form, to a certain extent, limits the functional diversity and adaptability of the robot. Specifically, simple structural designs often result in soft robots exhibiting the limitations of a single functional mode when performing tasks, making it difficult to meet the changing task requirements in dynamic environments.

[0003] As a mechanical structure with two stable states, a bistable structure can maintain either stable state in the absence of external forces; when external energy input is applied to cross the energy barrier, it can switch between the two stable states. This characteristic gives the bistable structure unique advantages in achieving flexible state transitions, energy saving, and stability. Currently, bistable structures have been studied and applied in many fields, such as micro-electromechanical systems and elastic elements. However, the application of bistable structures to soft robots to improve their task adaptability and interaction diversity has not been fully explored. How to utilize the state transition mechanism of the bistable structure to enable soft robots to have multifunctional modes has become a technical problem that needs to be solved urgently in this field. Summary of the Invention

[0004] To address the challenges of existing technologies, this paper proposes a multi-mode soft robot based on a bistable structure and its use method. This approach aims to leverage the characteristics of the bistable structure to provide the soft robot with diverse interactive and operational capabilities. Specifically, the bistable structure's two operating modes enable the soft robot to switch between functional modes, such as rapid grasping and crawling, meeting diverse operational requirements in different mission scenarios.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A multi-mode soft robot based on a bistable structure comprises a connecting base 1, four sets of identical power transmission components constituting a drive mechanism, and a top plate 9. Each set of power transmission components comprises an air hose 2, an actuating airbag 3, a lower elastic plate 4, a symmetrical hinge 5, a rigid gripper 6, an upper elastic plate 7, and a rotary hinge 8. These components are evenly arranged around the center of the connecting base 1. The power transmission components are powered by an air pump connected to the air hose 2. Specifically:

[0007] There are four air guide hoses 2 , which respectively pass through the air guide tube mounting holes 101 on the connection base 1 and are connected to the actuating airbag 3 , and the far ends are connected to the air pump.

[0008] The top of the lower elastic plate 4 is connected to the bottom of the upper elastic plate 7 via a symmetrical hinge 5 to form a revolute pair.

[0009] The top of the upper elastic plate 7 is connected to the top plate 9 via a rotary hinge 8 to form a rotary pair.

[0010] The base 1, lower elastic plate 4, hinge 5, upper elastic plate 7, hinge 8, and top plate 9 constitute a bistable structure. The initial state (first stable state) is when both elastic plates 4 and 7 are unchanged and the top plate 9 is at its farthest distance from the base 1. The trigger state (second stable state) is when both elastic plates 4 and 7 are unchanged and the top plate 9 is at its closest distance from the base 1. The critical state is when the elastic plate 7 reaches its maximum deformation and the elastic plate 4 is parallel to the base 1, or when one end of the elastic plate 4 is parallel to the base 1 after being compressed and unstable. Furthermore, any other state between the two stable states will automatically transition to a closer stable state based on the relative position of the current state and the critical state.

[0011] The rigid gripper 6 is fixed to the upper hinge of the symmetrical hinge 5 by means of bolts so as to move along with the upper elastic plate 7 .

[0012] Furthermore, one end of the symmetrical hinge 5 is attached to the lower elastic plate 4 and fixedly connected by bolts, and the other end is attached to the upper elastic plate 7 and connected by bolts, so that the lower elastic plate 4 and the upper elastic plate 7 form a revolute pair. The rotary hinge 8 is connected to the top plate 9 via a pin to form a revolute pair.

[0013] Furthermore, the connecting base 1 is provided with four groups of lower elastic plate mounting grooves 103 with small angles, which are used to constrain the angle of the lower elastic plate 4. Four pairs of through holes are provided along the circumference of the connecting base 1, which serve as lower elastic plate bolt holes 102 for bolt fixing. The connecting base 1 is provided with four inclined holes as air duct mounting holes 101, which are integrated through the bottom of the base 1 and are used to fix the air duct 2. The connecting bottom 1 is additionally provided with four through holes for using bolts to connect magnets or other connecting devices that can be combined with external robotic arms, etc. The bottom of the lower elastic plate 4 is inserted into the lower elastic plate groove 103 on the connecting base 1, and the bolt hole 102 passes through the lower elastic plate mounting groove 103 and is perpendicular to it, and the lower elastic plate 4 is fixed to the base 1 by bolts.

[0014] Furthermore, two openings are provided on the surfaces of the symmetrical hinge 5 and the rotary hinge 8, which are respectively fixed to the lower elastic plate 4 and the upper elastic plate 7 by means of bolts through the holes.

[0015] Furthermore, the lower elastic plate 4 is slightly longer than the upper elastic plate 7. By designing the angle between the slot 103 on the base 1 and the bottom surface of the lower elastic plate 4, the lengths of the upper and lower elastic plates are controlled so that they are nearly parallel in the triggered state (second stable state), facilitating bending under pressure. Specifically, if the length of the upper elastic plate 7 is L cm, the base thickness is d1 cm, and the top plate thickness is d2 cm, the length of the lower elastic plate 4 is L + d1 + d2 / 2 cm to L + d1 + d2 / 2 + 1 cm.

[0016] Furthermore, the lower elastic plate 4 and the upper elastic plate 7 are carbon fiber sheets, which have good bending energy storage capacity and can withstand torsion at a certain angle.

[0017] Furthermore, the symmetrical hinge 5 forms a revolute pair between the upper elastic plate 7 and the lower elastic plate 4. According to specific operation requirements, a torsion spring can be added to the symmetrical hinge 5 to provide additional force, thereby changing the threshold of the bistable trigger critical state.

[0018] A method for using a multi-mode soft robot based on a bistable structure, wherein the multi-mode soft robot has two working modes: a fast grasping mode and a crawling mode. The two working modes are used to switch between the fast grasping mode and the creeping crawling mode, and the operation mode includes the following:

[0019] Working mode 1: Fast grab mode

[0020] When the bistable structure is in its first stable state, sufficient external energy is applied to enable the system to overcome its energy barrier, transitioning from the first to the second stable state. This transition is accompanied by a rapid release of mechanical motion, enabling fast and efficient grasping of the target object. This mode can complete grasping tasks in a short period of time and is suitable for efficient target capture and precise positioning.

[0021] Working mode 2: crawling mode

[0022] When the bistable structure is in its second stable state, periodic external forces with energy lower than the required switching energy can cause the robot to vibrate or deform slightly while maintaining stability. Through appropriate structural design, these vibrations can generate propulsion on the contact surface, enabling the soft robot to crawl. This mode is suitable for slow, low-energy locomotion and is suitable for exploring complex terrain or confined spaces.

[0023] The details are as follows:

[0024] When working in fast grab mode:

[0025] The definitions of the initial state (first stable state) and the grasping state (second stable state) mentioned above are used.

[0026] The entire device is connected to the end of an external robotic arm, with the base 1 fixed to the robotic arm. The robotic arm drives the device toward the target object, and the top plate 9 contacts the target object and is subjected to pressure. The distance between the top plate 9 and the connection base 1 decreases, and the lower elastic plate 4 is compressed and bent. When the energy exceeds the critical threshold of the bistable structure, the soft robot quickly jumps from the first stable state to the second stable state, grasping the target object. After completing the rapid grasping action, the air pump at the far end inflates the actuating airbag 3 through the air guide hose 2, causing the lower elastic plate 4 to bend. When the critical threshold of the bistable structure is exceeded, the soft robot quickly jumps from the second stable state to the first stable state, pushing the rigid gripper 6 to loosen, releasing the target object and returning to the initial state. This reciprocating process can complete repeated grasping and releasing actions.

[0027] When operating in creep mode:

[0028] The bistable trigger state (i.e., the second stable state) is used as the initial state, with only the air guide hose 2 connected to the end of the soft robot. When one of the actuating airbags 3 is inflated and the other actuating airbags are not inflated, the top plate 9 tilts due to the unbalanced pressure. The upper elastic plate 7 corresponding to the inflated actuating airbag is compressed and bends together with the lower elastic plate 4. The elastic plates in the other three directions bend less, causing the soft robot to tilt in the forward direction. When the inflation reaches a certain level, the inflated actuating airbag 3 deflates. Since the center of gravity of the overall structure deviates from the central axis of the base 1 at this time, and the tip of the rigid gripper 6 in the direction corresponding to the inflated actuating airbag is at a greater angle to the ground, the rigid gripper 6 in that direction generates greater friction, driving the soft robot to move in that direction. In this way, the soft robot can complete continuous movement and perform free exploration activities within a certain space.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] (1) The present invention has a simple structure and an ingenious design. It realizes rapid switching between two stable states through the multi-hinge structure and the mechanical properties of the elastic plate, so that it has two working modes: rapid grasping and creeping.

[0031] (2) The power system of the soft robot provided by the present invention is deployed on a remote base, and the main body structure is simple and light in weight.

[0032] (3) The fast grasping mode of the soft robot provided by the present invention has the advantages of strong adaptability, fast response speed, and gentle grasping contact. It can also release the grasped object by pneumatic control, restore the initial state, and achieve repeated grasping.

[0033] (4) The peristaltic crawling mode of the soft robot provided by the present invention can freely explore the surrounding space, enhance the working accessibility of the flexible arm, and solve the problem of insufficient endurance of existing crawling robots.

[0034] In summary, the present invention has the advantages of simple structure, fast response, strong scalability and low cost. It solves the problem of the single working mode of existing soft robots. At the same time, it has two working modes: fast grasping and crawling. It has broad application prospects in operations in unstructured environments in the future. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic diagram of a first stable structure of the present invention;

[0036] Figure 2 is a schematic diagram of a second stable structure of the present invention;

[0037] Figure 3 It is a schematic structural diagram of the connection base of the present invention; Figure 3 (a) is the assembly structure diagram of the base 1, the air guide tube 2, and the actuating airbag 3. Figure 3 (b) and (c) are parts drawings of the connection base 1, which are used to show the position relationship of the openings of the connection base 1;

[0038] Figure 4 This is a schematic diagram of the working process of the present invention as a soft robot in a rapid grasping mode;

[0039] Figure 5 This is a schematic diagram of the working process of the present invention as a soft robot in creeping mode;

[0040] In the figure: 1 connecting base, 2 air guide hose, 3 actuating airbag, 4 lower elastic plate, 5 symmetrical hinge, 6 rigid gripper, 7 upper elastic plate, 8 connecting hinge, 9 top plate,

[0041] 101 air guide tube mounting hole; 102 lower elastic plate bolt hole; 103 lower elastic plate mounting groove. DETAILED DESCRIPTION

[0042] The present invention is described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, without departing from the scope of the present invention, a number of variations and improvements may be made by those skilled in the art. These all fall within the scope of protection of the present invention.

[0043] Figure 1 The figure shows a schematic diagram of the first stable-state structure of the soft robot, which includes a connecting base 1, an air hose 2, an actuating airbag 3, a lower elastic plate 4, a symmetrical hinge 5, a rigid gripper 6, an upper elastic plate 7, a connecting hinge 8, and a top plate 9. One end of the air hose 2 is connected to the air pump at the distal end, and the other end is connected to the actuating airbag 3 through a mounting hole 101 on the connecting base 1. The lower elastic plate 4 is inserted into a mounting groove 103 on the connecting base 1 and secured with bolts. Its bending angle is limited by the depth and position of the mounting groove 103. The upper and lower ends of the symmetrical hinge 5 are respectively attached to the lower elastic plate 4 and the upper elastic plate 7 and fixedly connected by bolts. Simultaneously, a rigid gripper 6 is provided at the upper end of the symmetrical hinge 5 to increase gripping force and improve gripping stability when grasping objects. The rotating hinge 8 is connected to the top plate 9 via a pin, forming a revolving pair. It is also attached to the upper elastic plate 7 and fixedly connected by bolts. The air guide hose 2, actuating airbag 3, lower elastic plate 4, symmetrical hinge 5, rigid gripper 6, upper elastic plate 7, and rotating hinge 8 are each arranged in four groups, evenly arranged around the center of the connecting base 1. Preferably, the elastic plate is made of carbon fiber sheeting, which has excellent bending energy storage capacity. Preferably, the triggering conditions of the bistable structure can be changed by adding torsion springs of different wire and diameters between the symmetrical hinge 5 and the rotating hinge 8. Lubricant can also be sprayed to reduce friction.

[0044] Figure 2 The diagram below shows the second stable state of the soft robot. When the top plate 9 contacts the target object, it moves downward under pressure, and the rotating hinge 8 rotates counterclockwise around the pin, driving the upper elastic plate 7 downward and outward along the axis. The upper end of the symmetrical hinge 5 rotates around the pin, reducing the intermediate angle, and the lower elastic plate 4 is compressed and bent outward. When the upper elastic plate 7 is level with the plane of the connecting base 1, the critical state is exceeded, the lower elastic plate 4 rebounds, and the hinge 5 rotates counterclockwise, driving the upper elastic plate 7 to quickly flip and fall to a stable position, where the rigid gripper 6 grasps the target object. To return to the first stable state, the four actuating airbags 3 can be inflated simultaneously. The top plate 9 is uniformly forced upward, and the lower elastic plate 4 is compressed and bent. When the critical position is exceeded, the lower elastic plate 4 returns to its initial position and releases the stored energy. The top plate 9 quickly rebounds to its initial position and releases the object. Repeating this process allows for rapid and repeatable grasping and releasing operations.

[0045] like Figure 3 This is a schematic diagram of the structure of the connecting base 1 of the present invention, manufactured using 3D printing technology. Hole 101 is the fixing hole for the air hose. The air hose 2 is introduced through the hole on the bottom surface of the base 1 and is divided into four evenly distributed pipes on the upper surface of the connecting base 1, corresponding to the directions of the four sets of lower elastic plates 4, used to apply forces to the elastic plates in different directions. The connecting base 1 is provided with four elastic plate mounting slots 103 inclined 20 degrees from the vertical to constrain the rotation angle of the lower elastic plates 4. Furthermore, four pairs of holes 102 are evenly distributed around the connecting base 1 for passing bolts to fasten the elastic plates 4.

[0046] like Figure 4 This is a schematic diagram of the working process of the bistable soft robot in the fast grasping mode. Its working process is:

[0047] In the first step, the soft robot is connected to the end of an external robotic arm through a magnet, vacuum or other means, and is carried to the working position by the external robotic arm. When the soft robot contacts the surface of the object, the top plate 9 is pressurized, and the pressure is transmitted to the lower elastic plate 4 through the upper elastic plate 7. The lower elastic plate 4 bends, and the upper elastic plate 7 expands outward with the rotation of the symmetrical hinge 5. The angle between the symmetrical hinges 5 becomes smaller, and the distance between the top plate 9 and the connecting base 1 is reduced.

[0048] In the second step, when the upper elastic plate 7 is parallel to the bottom surface, the energy threshold of the bistable structure is reached. The pressure on the top plate 9 is no longer balanced by the perpendicular component of the axial force of the elastic plate 7. The bistable structure jumps, and the top plate 9 drops rapidly. Simultaneously, the lower elastic plate 4 is no longer under pressure and quickly rebounds under the action of internal forces, driving the symmetrical hinge 5 and the rigid gripper 6 to move toward the center to clamp the target object.

[0049] In the third step, once the soft robot has reached the desired release position, air is simultaneously inflated through the air hose 2 to the four actuating airbags 3, pushing the top plate 9 upward. When the upper elastic plate 7 becomes parallel to the bottom surface, the critical state of the bistable structure is exceeded. The lower elastic plate 4 rebounds, pushing the symmetrical hinge 5, rigid gripper 6, upper elastic plate 7, and other structures upward, quickly releasing the object.

[0050] In the fourth step, the four actuating air bags 3 are deflated through the air guide hose 2 to return to the initial state, and the next clamping operation can be performed.

[0051] like Figure 5 The following is a schematic diagram of the working process of the bistable soft robot in the creeping mode.

[0052] In the first step, the bistable trigger state (i.e., the second stable state) is used as the initial state, with only the air guide hose 2 connected to the end of the soft robot. When one of the actuating airbags 3 is inflated while the others are not, the top plate 9 tilts due to the unbalanced pressure. The upper elastic plate 7 corresponding to the inflated actuating airbag is compressed, bending together with the lower elastic plate 4. The elastic plates in the other three directions bend less, causing the soft robot to tilt in the forward direction.

[0053] In the second step, when the inflation reaches a certain level, the actuating airbag 3 that has been inflated is deflated. Since the center of gravity of the overall structure deviates from the central axis of the base 1 at this time, and the angle between the tip of the rigid gripper 6 in the direction corresponding to the inflated actuating airbag and the ground is larger, the rigid gripper 6 in that direction generates greater friction, driving the soft robot to move in that direction.

[0054] By repeating this process, the soft robot can complete continuous movement and perform free exploration activities within a certain space.

[0055] While the basic principles of the present invention have been described above in conjunction with specific embodiments, it should be noted that the advantages, strengths, and effects mentioned in the present invention are merely illustrative and non-restrictive, and it should not be assumed that these advantages, strengths, and effects are required of each embodiment of the present application. Furthermore, the specific details disclosed above are provided for illustrative purposes and to facilitate understanding, and are not intended to be limiting. These details do not limit the present invention to necessarily being implemented using these specific details.

[0056] The above-described embodiments merely express the implementation methods of the present invention, but should not be understood as limiting the scope of the patent of the present invention. It should be pointed out that for those skilled in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A multi-mode soft robot based on a bistable structure, characterized in that: The multi-mode soft robot comprises a connecting base (1), four groups of power transmission components with the same structure for constituting a driving device, and a top plate (9), wherein each group of power transmission components comprises an air guide hose (2), an actuating air bag (3), a lower elastic plate (4), a symmetrical hinge (5), a rigid gripper (6), an upper elastic plate (7), and a rotary hinge (8), which are evenly arranged around the center of the connecting base (1) as an axis, and the power source of the power transmission components is provided by an air pump extended from the air guide hose (2); There are four air guide hoses (2) in total, which respectively pass through the air guide tube mounting holes 101 on the connection base (1) and are connected to the actuating airbag (3), and the far end is connected to the air pump; The top of the lower elastic plate (4) is connected to the bottom of the upper elastic plate (7) via a symmetrical hinge (5) to form a revolving pair; The top of the upper elastic plate (7) is connected to the top plate (9) via a rotary hinge (8) to form a rotary pair; The base (1), the lower elastic plate (4), the symmetrical hinge (5), the upper elastic plate (7), the rotary hinge (8), and the top plate (9) form a bistable structure; The rigid gripper (6) is fixed to the upper hinge of the symmetrical hinge (5) so as to move along with the upper elastic plate (7); The bistability of the bistable structure is: The state in which the lower elastic plate (4) and the upper elastic plate (7) are both non-deformed and the top plate (9) is farthest from the connection base (1) is taken as the initial state, which is the first stable state; the state in which the lower elastic plate (4) and the upper elastic plate (7) are both non-deformed and the top plate (9) is closest to the connection base (1) is taken as the trigger state, which is the second stable state; the state in which the upper elastic plate (7) is deformed to the maximum and the lower elastic plate (4) is parallel to the connection base (1) or one end of the lower elastic plate (4) is parallel to the connection base (1) after being compressed and unstable is taken as the critical state; A torsion spring can be added to the symmetrical hinge (5) to provide additional force, thereby changing the threshold of the bistable triggering critical state.

2. A multi-mode soft robot based on a bistable structure according to claim 1, characterized in that: Any other state between two stable states will automatically transition to a closer stable state based on the relative position of the current state to the critical state.

3. The multi-mode soft robot based on a bistable structure according to claim 1, characterized in that: One end of the symmetrical hinge (5) is attached to the lower elastic plate (4) and fixedly connected by bolts, and the other end is attached to the upper elastic plate (7) and connected by bolts, so that the lower elastic plate (4) and the upper elastic plate (7) form a rotating pair; the rotating hinge (8) is connected to the top plate (9) through a pin shaft to form a rotating pair.

4. The multi-mode soft robot based on a bistable structure according to claim 1, characterized in that: The connecting base (1) is provided with four groups of lower elastic plate mounting grooves (103) inclined at small angles, which are used to constrain the angle of the lower elastic plate (4); four pairs of through holes are provided along the circumference of the connecting base (1), which serve as lower elastic plate bolt holes (102); the bottom of the lower elastic plate (4) is inserted into the lower elastic plate mounting groove (103) on the connecting base (1), and the bolt holes (102) pass through the lower elastic plate mounting groove (103) and are perpendicular to the lower elastic plate, and the lower elastic plate (4) is fixed to the connecting base (1) by bolts; two openings are provided on the surfaces of the symmetrical hinge (5) and the rotary hinge (8), which are respectively fixed to the lower elastic plate (4) and the upper elastic plate (7) by bolt penetration.

5. The multi-mode soft robot based on a bistable structure according to claim 1, characterized in that: The lower elastic plate (4) is longer than the upper elastic plate (7). By designing the angle between the lower elastic plate mounting groove (103) and the bottom surface of the lower elastic plate (4), and controlling the lengths of the upper and lower elastic plates, the plates are close to being parallel in the triggered state, thereby facilitating bending under pressure.

6. The multi-mode soft robot based on a bistable structure according to claim 5, characterized in that: If the length of the upper elastic plate (7) is L cm, the thickness of the base is d1 cm, and the thickness of the top plate is d2 cm, the length of the lower elastic plate (4) is L+d1+d2 / 2 cm~L+d1+d2 / 2+1 cm.

7. The multi-mode soft robot based on a bistable structure according to claim 1, characterized in that: The lower elastic plate (4) and the upper elastic plate (7) are carbon fiber sheets.

8. A method for using the multi-mode soft robot based on a bistable structure according to any one of claims 1 to 7, characterized in that: The multi-mode soft robot has two working modes: fast grasping mode and crawling mode. The two working modes are used to switch between fast grasping and creeping modes. The operation modes include the following: Working mode 1: Fast grab mode When the bistable structure is in the first stable state, the external energy is applied to realize the transition from the first stable state to the second stable state, thereby achieving fast and efficient grasping of the target object; Working mode 2: crawling mode When the bistable structure is in the second stable state, by periodically applying external forces with energy lower than the energy required for state switching, the robot can produce small vibrations or deformations while maintaining a stable state; thereby generating a propulsion force on the contact surface, realizing the crawling motion of the soft robot.

9. The method for using a multi-mode soft robot according to claim 8, characterized in that: The details are as follows: When working in fast grab mode: The entire device is connected to the end of an external robotic arm, the connecting base (1) is fixed on the robotic arm, the robotic arm drives the device close to the target object, the top plate (9) contacts the target object and is subjected to pressure, the distance between the top plate (9) and the connecting base 1 is reduced, the lower elastic plate (4) is compressed and bent, and when the energy exceeds the critical threshold of the bistable structure, the soft robot quickly jumps from the first stable state to the second stable state and grasps the target object; after completing the rapid grasping action, the air pump at the far end inflates the actuating airbag (3) through the air guide hose (2), and the lower elastic plate (4) bends. When the critical threshold of the bistable structure is exceeded, the soft robot quickly jumps from the second stable state to the first stable state to push the rigid gripper (6) to loosen, release the target object, and return to the initial state; This process is repeated to complete the repeated grabbing and releasing actions. When operating in creep mode: With the bistable trigger state as the initial state, the end of the soft robot is only connected to the air guide hose (2); when one of the actuating airbags (3) is inflated and the other actuating airbags are not inflated, the top plate (9) is tilted by the unbalanced pressure, and the upper elastic plate (7) corresponding to the inflated actuating airbag is compressed and bends together with the lower elastic plate (4), and the elastic plates in the other three directions are less bent, so that the soft robot tilts in the forward direction; when the inflation reaches a certain level, the actuating airbag (3) performing the inflation operation is deflated, because at this time the center of gravity of the overall structure deviates from the central axis of the connection base (1), and the angle between the tip of the rigid gripper (6) in the direction corresponding to the inflated actuating airbag and the ground is larger, so the rigid gripper (6) in this direction generates friction, driving the soft robot to move in this direction; in this way, the soft robot can complete continuous movement and perform free detection activities within a certain space.

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