A bionic soft arm for hugging robots and its control system

Abstract

This invention relates to the field of intelligent robot technology, and in particular to a bionic soft arm for hugging robots and its control system. The arm comprises a single, curved airbag, which is a hollow cavity made of flexible material and has at least one bending deformation structure; at least one set of inner contraction airbags a1 / a2 disposed at both inner ends of the curved airbag; and at least one set of outer patting airbags b1 / b2 or wire-driven modules disposed at both outer ends of the curved airbag. The inner contraction airbags a1 / a2 and the outer patting airbags b1 / b2 or wire-driven modules are fixed to the curved airbag via high-frequency compression or mechanical connection. The curved airbag undergoes bending deformation after inflation, providing three curved airbag configurations: a symmetrical vortex configuration, a Z-shaped sawtooth plus trimmed plate configuration, and a pleated configuration, as well as two patting implementation methods: purely pneumatic and wire-driven assisted.

Description

Technical Field

[0001] This invention relates to the field of intelligent robot technology, and in particular to a bionic soft arm for hugging robots and its control system. Background Technology

[0002] With the increasing application of robotics in service and companionship, bionic arms with soft contact capabilities have become a hot topic in human-computer interaction research. Especially in scenarios requiring close contact, such as hugging robots, robotic arms need to be able to simulate human actions like hugging, patting, and holding on, while ensuring safety and comfort.

[0003] In existing technologies, most bionic arms use rigid joints or motor-driven methods. Although they can achieve basic bending movements, they have the following shortcomings: First, the rigid structure results in a stiff contact and lacks a soft touch, which can easily cause discomfort to users. Second, the drive mechanism is complex and costly, which is not conducive to large-scale production and popularization. Third, it is difficult to achieve multiple human-like movements such as bending, hugging, and patting on the same arm at the same time. In particular, the patting movement often requires an additional mechanical transmission mechanism, which increases the complexity of the structure and the failure rate.

[0004] In recent years, soft robotics technology based on flexible materials has developed, leading to the emergence of bionic arm solutions using airbags. However, existing airbag-driven solutions still have limitations: some solutions can only achieve a single bending motion, failing to provide a combined interactive experience of hugging and patting; while some solutions achieve multiple actions, the structural design of the bending airbag is not optimized enough, resulting in limited bending angles or unnatural movements; furthermore, the patting function in existing solutions is mostly implemented through pure pneumatic control, and the response speed and rhythm control accuracy need improvement.

[0005] Therefore, there is an urgent need for a bionic soft arm with a simple structure, natural movements, and the ability to perform multiple human-like actions such as bending, hugging, patting, and holding on, in order to meet the needs for soft contact and emotional expression in human-computer interaction. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by proposing a bionic soft arm for embracing robots and its control system.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A bionic soft arm for hugging robots includes: A single curved airbag, wherein the curved airbag is a hollow cavity made of flexible material and has at least one bending deformation structure; At least one set of inner contraction airbags a1 / a2 is disposed at both inner ends of the curved airbag; At least one set of outer-side airbags b1 / b2 or wire-driven modules are disposed at both ends of the outer side of the curved airbag; The inner contraction airbags a1 / a2 and the outer flapping airbags b1 / b2 or the wire-driven module are respectively fixed to the bending airbag by high-frequency compression or mechanical connection. The curved airbag inflates and deforms, the inner contraction airbags a1 / a2 inflates and increases the curvature to achieve a hugging action, and the outer patting airbags b1 / b2 inflates and contracts or the wire-driven module retracts the wire to pull the end of the curved airbag to achieve a patting action.

[0008] Preferably, the bending deformation structure of the bending airbag is a symmetrical vortex configuration, the outline of which includes symmetrically distributed double wing sections and a central vortex section, and after inflation, it forces the arm to bend inward by its own large curvature.

[0009] Preferably, the bending deformation structure of the bending airbag is Z-shaped with a serrated center, and long strips are provided above and below it. After inflation, the Z-shaped serrations unfold and form a triangular stable structure with the strips, and bending occurs because the length of the strips is fixed.

[0010] Preferably, the bending deformation structure of the bending airbag is provided with continuous folds on the outer wall. When inflated, the folds unfold, causing the outer side to elongate more than the inner side, and the arm bends due to differential deformation.

[0011] Preferably, the outer flap airbag b1 / b2 or the wire-driven module is an outer flap airbag b1 / b2, which is composed of multiple interconnected small air chambers. When inflated, it contracts and shortens as a whole, pulling and bending the end of the airbag; or it is a wire-driven module, including a wiring channel, nylon wire, winch and motor, which simulates flapping by winding and unwinding the wire.

[0012] Preferably, the curved airbag has small square pressing areas at both ends to simulate the wrist, and these areas have weaker mechanical properties than other parts after inflation.

[0013] Preferably, the inner contraction airbags a1 / a2 and the outer patting airbags b1 / b2 are both composed of multiple interconnected small air cells forming a Pouch Motor structure, and the inner contraction airbags a1 / a2 and the outer patting airbags b1 / b2 are both composed of multiple small air cells.

[0014] Preferably, the parameters of the folds are designed according to the functional segment partitions, and the axial unfoldable amount of all folds is 0.5-3cm.

[0015] In another aspect, the present invention provides a control system for controlling a bionic soft arm for a hugging robot as described in any of the preceding claims, comprising: a trigger unit, a control unit, an air source device, and seven air valves; the control unit is configured to execute the following control sequence: in the hugging phase, inflating the bending airbag; in the tightening phase, inflating the inward contracting airbags a1 / a2; in the patting phase, patting the outward airbags b1 / b2 with a specific rhythm of inflation and deflation or controlling the wire drive module to retract and extend the wire; and in the release phase, releasing a specific amount of airbag gas.

[0016] Preferably, the control timing further includes a delay phase before the embracing phase to maintain the constant air pressure of the bending airbag for a first predetermined time; and a pause phase after the embracing phase to maintain the constant air pressure of the inner contracting airbags a1 / a2 for a second predetermined time.

[0017] The present invention has the following beneficial effects: This invention provides three bending airbag schemes: symmetrical vortex configuration, Z-shaped sawtooth and cut-piece configuration, and pleated configuration, as well as two tapping implementation methods: pure pneumatic and wire-driven assisted.

[0018] Through the coordinated action of the bending airbags and the inner contracting airbags a1 / a2, the outer patting airbags b1 / b2, or the wire-driven module, various human-like movements can be achieved, either individually or simultaneously, such as bending and hugging, tightening the embrace, and rhythmic patting. The movements are continuous and gentle, closely resembling the real human hugging experience, significantly enhancing the affinity and realism of human-computer interaction.

[0019] All airbags are made of flexible materials through high-frequency pressing, eliminating the need for complex mechanical transmission components. The pressing edge width and nozzle layout of the curved airbags have been optimized, and the mature manufacturing process is suitable for mass industrial production, effectively reducing manufacturing costs.

[0020] The entire arm is made of flexible airbags with no exposed rigid metal parts. Even when inflated, it has good elasticity and cushioning capabilities, avoiding the risk of collision damage that may be caused by traditional rigid structures. It is particularly suitable for applications that require frequent physical contact, such as children's robots and companion robots.

[0021] Through multi-valve collaborative control and biomimetic timing algorithms, precise timing control of actions such as hugging, tightening, and patting can be achieved. The frequency and amplitude of the patting action can be flexibly adjusted by changing the inflation / deflation rhythm or the speed of the linear motor to meet personalized needs in different interaction scenarios.

[0022] The pleat parameters or Z-shaped sawtooth pressing spacing of the curved airbag are designed in sections according to different functional segments of the human body such as elbow joint, shoulder joint, and wrist, so that the bending angle and flexibility of the arm in different parts are closer to the physiological structure of the human body, improving the fit and comfort when wearing or hugging.

[0023] The arm structure of this invention can be seamlessly integrated with a robot or the robot's torso, and the control system can be embedded inside the core, resulting in a clean and aesthetically pleasing overall appearance. Simultaneously, the control system has a reserved trigger interface, allowing for easy linkage with external sensors (such as touch sensors, proximity sensors, etc.) to achieve intelligent, proactive hugging response. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention; Figure 3 This is a schematic diagram of the structure of Embodiment 3 of the present invention; Figure 4 This is a schematic diagram of the structure of Embodiment 4 in this invention; Figure 5 This is a schematic diagram of the wire drive module in this invention.

[0025] Attached diagram descriptions: 100-bending airbag, 102-L-shaped air nozzle, 130-pleats, 140-wiring channel, 160-DC torsion motor, 170-winch, 180-Z-shaped serration, 190-long strip, a1 / a2-contraction airbag, b1 / b2-patting airbag. Detailed Implementation

[0026] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0027] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0029] This invention provides a bionic soft arm for hugging robots, consisting of a single bending airbag 100 and multiple sets of contractile airbags a1 / a2 and patting airbags b1 / b2. Human-like movements such as bending, hugging, patting, and holding are achieved through a pneumatic control system.

[0030] The curved airbag serves as the main body of the arm, and its curved posture is generated by inflation and deformation. The contractile airbags a1 / a2 are attached to the inside of the curved airbag. The tapping airbags b1 / b2 are attached to the outside of the curved airbag. The contraction airbags a1 / a2 and the patting airbags b1 / b2 are used to increase the hugging force and simulate patting actions, respectively. A single curved airbag 100 is installed inside the robot. A contractile airbag a1 / a2 is located at each of the inner ends of the curved airbag 100, and a slapping airbag b1 / b2 is located at each of the outer ends. All airbags are bonded together using high-frequency compression. The curved airbag 100 has a compression edge, with two L-shaped air nozzles 102 facing each other and positioned in the middle of the outer wall of the curved airbag. The contractile airbags a1 / a2 and slapping airbags b1 / b2 are bonded to the curved airbag 100 using high-frequency compression. The short side that is fixedly connected is the adhesive side. The contractile airbags a1 / a2 and slapping airbags b1 / b2 span the compression edge of the curved airbag, and their adhesive sides are symmetrically bonded to the upper and lower parts of the curved airbag 100, but not adhered to the compression edge of the curved airbag.

[0031] At a certain distance behind the ends of the curved airbag 100, there is a small square pressing area on each side. The line connecting the center points of the two small squares is perpendicular to the direction of the airbag, so that its mechanical properties are weaker than other parts after inflation, which is used to simulate the human wrist.

[0032] All airbags are made of flexible materials through high-frequency bonding.

[0033] The technical solution of the present invention will be described in detail below with reference to four specific embodiments.

[0034] Example 1: like Figure 1 As shown, the bending airbag 100 in this embodiment is a long strip airbag with a symmetrical vortex configuration. Its outline includes symmetrically distributed contraction airbags a1 / a2 and patting airbags b1 / b2. After inflation, the airbag expands and gains rigidity. Due to its large curvature design, the rigidity forces the fabric cover to bend inward, driving the bionic soft arm to bend to one side.

[0035] Tap the end of the curved airbag connected to airbag b1 / b2, ensuring it lies flat against the outside of the curved airbag when deflated. When inflated, airbag a1 / a2 contracts, shortening in length and pulling the palm-shaped portion of the curved airbag end. After deflation, the palm-shaped portion of the curved airbag end returns to its original shape. Repeating this multiple times with a specific inflation rhythm can simulate a human hug.

[0036] The contractile airbags a1 / a2 are used to simulate human muscles. After the bending airbag 100 is inflated, in a specific scenario, the contractile airbags a1 / a2 are driven by gas, pulling the inflated bending airbag 100, making the curvature of the bending airbag greater. At the same time, the contractile airbags a1 / a2 expand inward, making the hug stronger and giving the person being hugged a feeling of being held tightly.

[0037] The symmetrical vortex configuration of the curved airbag 100 in this embodiment has a large curvature and conforms to ergonomic design, which can fit the human body and provide a hugging experience with a sense of fit and envelopment. It is easy to manufacture and suitable for mass production.

[0038] Example 2: like Figure 2 As shown, the bending airbag 100 in this embodiment has a Z-shaped serrated center 180, with a long strip 190 on its upper and lower sides to restrict the range of motion of the central airbag. After inflation, the central Z-shaped serrated airbag 180 unfolds to form an asymmetrical extension that bends the arm.

[0039] The central Z-shaped serrated airbag 180 is actually composed of several interlocking airbags, which are bent back and forth along the dividing lines between the interlocking airbags to form a Z-shape. When inflated, the upper and lower panels 190 and the central serrated airbag 180 form a triangle, thus creating a stable structure. The triangular structures formed between the upper and lower panels and the central serrated airbag are all isosceles triangles, with the apex angle of the upper isosceles triangle being larger than the apex angles of the two lower isosceles triangles, resulting in an overall curved structure. The upper and lower panels 190 have a fixed length and do not change. With the central Z-shaped serrated airbag remaining unchanged, the specific shape and curvature of the inflated curved airbag are related to the length of the upper and lower panels.

[0040] The central Z-shaped serrated airbag 180 has a pressing edge, and two L-shaped air nozzles 102 are perpendicular to the long side of the airbag and located in the middle of the airbag. Each compartment of the central Z-shaped serrated airbag is provided with an air guide strip 181 to allow gas to be quickly introduced into the entire airbag.

[0041] The structure and function of the contractile airbags a1 / a2 are the same as in Example 1.

[0042] The pressing distance between the central Z-shaped grid airbag and the upper and lower strip bottom material on the curved airbag is designed according to the functional sections, so as to simulate the small-angle bending at the elbow joint and the large-angle bending at the shoulder joint.

[0043] Example 3: like Figure 3 As shown, the curved airbag 100 in this embodiment is a long strip-shaped airbag with continuous folds 130 on its outer wall. When inflated, the folds 130 unfold, causing the outer side of the curved airbag 100 to elongate more than the inner side. Due to differential deformation, the bionic soft arm bends to the inner side.

[0044] The structure and function of the contraction airbags a1 / a2 and the patting airbags b1 / b2 are the same as in Example 1.

[0045] The pleat parameters on the bending airbag 100 are designed in sections according to functional segments, so that it simulates the small-angle bending at the elbow joint and the large-angle bending at the shoulder joint. The shoulder segment has multiple pleats, the elbow segment has multiple pleats, and the wrist segment has multiple pleats. The axial unfolding amount of all pleats is 0.5-3cm.

[0046] In this embodiment, all actions are completed by the inflation and deflation of the airbag, without any mechanical transmission parts. The structure is simple, the manufacturing cost is low, and it is suitable for mass production.

[0047] Example 4: like Figure 4 As shown, the bending airbag 100 in this embodiment is a long strip-shaped airbag with continuous folds 130 on its outer wall. When inflated, the folds 130 unfold, and the arm bends due to differential deformation.

[0048] Figure 5 The structure of the wire-driven module is shown. At each end of the outer side of the curved airbag 100, there are two wiring channels 140, symmetrically arranged along the central axis of the airbag and consisting of 12 small cylindrical channels at equal intervals. Nylon wires pass through the wiring channels 140, one end connected to a winch 170 mounted on a DC torsion motor 160, and the other end connected to the end of the curved airbag 100, forming the wire-driven module used to simulate human tendons.

[0049] When the wire-driven module is working, the winch 170 rotates clockwise to wind up the nylon line, shortening its length and pulling the palm-shaped part at the end of the curved airbag. When releasing the palm, the current direction changes, and the winch 170 rotates counter-clockwise to release the nylon line 150, restoring the line length to its pre-raised position, and the palm-shaped part at the end of the curved airbag returns to its original shape. This process is repeated multiple times, driving the motor with a specific rhythm to simulate a pat during a human hug.

[0050] The structure and function of the contractile airbags a1 / a2 are the same as in Example 1.

[0051] The pleat parameters on the curved airbag 100 are designed in sections according to functional segments. The shoulder segment has multiple pleats, the elbow segment has multiple pleats, and the wrist segment has multiple pleats. The axial unfolding amount of all pleats is 0.5-3cm.

[0052] The wire drive module consists of a 12V DC motor, a winch, and a roll of nylon rope. There are two wire drive modules, each acting on one end of the airbag. The drive part (motor and winch) of the wire drive module is installed in the mechanism, while the nylon rope is installed on the airbag.

[0053] The working principles of tightening airbags a1 / a2 and patting airbags b1 / b2: The bending airbag 100 has a preset bending shape in its initial state. The main airbag has a certain degree of flexibility and elastic recovery capability, and can produce continuous and stable deformation under air pressure. With the help of external auxiliary airbags, it can further change the local curvature to achieve different degrees of bending adjustment and dynamic interaction.

[0054] The tightening airbags are respectively located on the left and right sides inside the main airbag. Each tightening airbag consists of a Pouch Motor structure composed of multiple sequentially connected small air cells. The small air cells are continuously connected and together form a flexible drive unit capable of contraction displacement along the length direction. The tightening airbags are fixedly connected to the corresponding inner surface of the main airbag via a pressing area. When the tightening airbags are inflated, the small air cells gradually bulge and undergo geometric changes, causing the entire Pouch Motor structure to contract along the length direction. This applies a continuous traction force to the corresponding side of the main airbag through the pressing area, further shortening the length of that side. Since the length change on the other side of the main airbag is relatively small, the local bending radius of the corresponding side of the main airbag decreases, and the local curvature increases, ultimately increasing the overall degree of bending or shifting the bending center to complete the attitude adjustment.

[0055] The tapping airbags are respectively located on the left and right sides of the main airbag. Each tapping airbag consists of a Pouch Motor structure composed of multiple sequentially connected small air cells, which are fixed to the corresponding side surface of the main airbag. Unlike the tightening airbag, the tapping airbag mainly generates dynamic deformation through periodic inflation and deflation. When the tapping airbag is inflated and deflated at a preset frequency, each small air cell expands and contracts sequentially. Combined with the elastic recovery characteristics of the main airbag after inflation, a periodic local force is applied to the corresponding area of ​​the main airbag, causing the main airbag to generate continuous local curvature perturbations based on its original bending posture. This perturbation does not change the overall basic bending shape of the main airbag, but forms a dynamic deformation with a certain frequency and amplitude in a local area, thereby transmitting a periodic tapping sensation to the contact object and improving the tactile expression capability of the flexible robot in the human-computer interaction process.

[0056] When the left tightening airbag works alone, the left Pouch Motor structure contracts along its length after inflation, and further shortens the left side of the main airbag by pulling it through the compression area, causing the local curvature on the left side to continue to increase, and the overall bending degree of the main airbag to further increase, or causing the bending center of gravity to shift to the left side on the basis of the original bending.

[0057] When the right-side tightening airbag works alone, its working principle is the same as that of the left side. By pulling the right side of the main airbag, the curvature of the right side is increased, thereby increasing the overall degree of bending or shifting the bending center to the right.

[0058] When the left and right airbags are inflated simultaneously, the Pouch Motor structures on both sides contract axially at the same time. This simultaneous traction from both sides further enhances the overall bending of the main airbag and maintains a relatively balanced bending posture, preventing posture deviation caused by unilateral contraction.

[0059] When the left-side tapping airbag operates independently, the control system controls the left-side Pouch Motor structure to periodically inflate and deflate according to a set frequency. This causes the left side of the main airbag to maintain its original curved state while generating periodic local curvature changes, and transmits a continuous tapping sensation to the object it is in contact with.

[0060] When the right-side airbag works alone, its mechanism of action is the same as that of the left-side airbag, only the area of ​​action changes to the right side of the main airbag.

[0061] When the airbags on both sides work synchronously, the Pouch Motor structures on both sides inflate and deflate periodically according to the same or different control parameters, causing local dynamic deformation on both sides of the main airbag at the same time. This creates tactile interaction effects such as synchronous or alternating tapping on both sides on the basis of the original bending posture, so as to meet the usage needs of different human-computer interaction scenarios.

[0062] The tightening airbag and the tapping airbag can work together. When the left tapping airbag and the right tightening airbag work simultaneously, the right tightening airbag first pulls the right side of the main airbag through axial contraction, causing the main airbag to bend to the right and increase the local curvature on the right side. At the same time, the left tapping airbag continuously inflates and deflates periodically, driving the left side of the main airbag to produce local periodic deformation in this bent state, so that the overall structure outputs a rhythmic tapping sensation while maintaining the bent posture.

[0063] When the right-side tapping airbag and the left-side tightening airbag work simultaneously, the left-side tightening airbag causes the left side of the main airbag to further contract and form a larger local curvature, while the right-side tapping airbag produces periodic local deformation in the corresponding area. The two driving methods work together to improve the robot's motion performance and interactive experience during human-robot contact.

[0064] The tightening airbag is responsible for establishing the spatial posture and contact pressure of the main airbag, while the patting airbag generates local dynamic disturbances based on this posture. The two are independent of each other but can be controlled in a coordinated manner, enabling the robot to achieve multiple tactile interaction modes such as wrapping, fitting, tightening and patting, either separately or simultaneously, without the need for additional independent mechanical drive mechanisms. This reduces the overall structural complexity and improves flexibility, safety and naturalness of interaction.

[0065] This application also discloses a system for controlling the aforementioned bionic soft arm, comprising: The trigger unit is used to generate a trigger signal; A control unit, connected to the triggering unit, is used to receive the trigger signal; The gas source device is connected to the control unit; Seven air valves are connected to the air lines between the air source device and the contraction airbags a1 / a2, the patting airbags b1 / b2 and the bending airbag 100, and are controlled by the control unit. The control unit is configured to execute the following control timing sequence: S1, Hugging Phase: Control the air source device and inflate the bending airbag 100 through the air valve to bend the arms and achieve the hugging action; S2, Tightening Phase: Control the air source device and inflate the contraction airbags a1 / a2 through the air valve to make the arm bend more widely; S3, Tap-tap stage: Control the air source device and inflate the tap-tap airbags b1 / b2 with a specific rhythm through the air valve and then deflate them, so that the arm end is raised and then quickly lowered to simulate a tap. S4. Release Phase: After the embrace phase, control the air valve to release the gas in the contraction airbags a1 / a2 and the bending airbag 100, so that the arm returns to its initial state.

[0066] The control timing also includes a delay phase between the opening phase and the embracing phase, during which the control unit maintains a constant air pressure in the bending airbag 100 for a first predetermined time; the control timing also includes a pause phase after the embracing phase, during which the control unit maintains a constant air pressure in the contracting airbags a1 / a2 for a second predetermined time.

[0067] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A bionic soft arm for hugging robots, characterized in that, include: A single curved airbag, wherein the curved airbag is a hollow cavity made of flexible material and has at least one bending deformation structure; At least one set of inner contraction airbags a1 / a2 is disposed at both inner ends of the curved airbag; At least one set of outer-side airbags b1 / b2 or wire-driven modules are disposed at both ends of the outer side of the curved airbag; The inner contraction airbags a1 / a2 and the outer flapping airbags b1 / b2 or the wire-driven module are respectively fixed to the bending airbag by high-frequency compression or mechanical connection. The curved airbag inflates and deforms, the inner contraction airbags a1 / a2 inflates and increases the curvature to achieve a hugging action, and the outer patting airbags b1 / b2 inflates and contracts or the wire-driven module retracts the wire to pull the end of the curved airbag to achieve a patting action.

2. The bionic soft arm for hugging robots according to claim 1, characterized in that, The bending deformation structure of the bending airbag is a symmetrical vortex configuration. Its outline includes symmetrically distributed contraction airbags a1 / a2 and patting airbags b1 / b2. After inflation, it forces the arm to bend inward due to its large curvature.

3. The bionic soft arm for hugging robots according to claim 1, characterized in that, The bending deformation structure of the bending airbag is Z-shaped with a serrated center and long strips on its upper and lower sides. After inflation, the Z-shaped serrations unfold and form a stable triangular structure with the strips, and bending occurs because the length of the strips is fixed.

4. A bionic soft arm for hugging robots according to claim 1, characterized in that, The bending deformation structure of the bending airbag is that the outer wall is provided with continuous folds. When inflated, the folds unfold, causing the outer side to elongate more than the inner side, and the arm bends due to differential deformation.

5. A bionic soft arm for hugging robots according to claim 1, characterized in that, The outer flap airbag b1 / b2 or the wire-driven module is an outer flap airbag b1 / b2, which consists of multiple interconnected small air chambers. When inflated, it contracts and shortens as a whole, pulling and bending the end of the airbag; or it is a wire-driven module, which includes a cable channel, nylon cable, winch and motor, and simulates flapping by winding and unwinding the cable.

6. A bionic soft arm for hugging robots according to claim 1, characterized in that, The curved airbag has small square pressing areas at both ends to simulate the wrist. When inflated, these areas have weaker mechanical properties than other parts.

7. A bionic soft arm for hugging robots according to claim 1, characterized in that, The inner contraction airbags a1 / a2 and the outer patting airbags b1 / b2 are both composed of multiple interconnected small air cells forming a Pouch Motor structure.

8. A bionic soft arm for hugging robots according to claim 4, characterized in that, The parameters of the folds are designed according to the functional segment partitions, and the axial unfoldable amount of all folds is 0.5-3cm.

9. A control system for controlling a bionic soft arm for a hugging robot as described in any one of claims 1-8, characterized in that, include: The device includes a trigger unit, a control unit, an air source device, and seven air valves. The control unit is configured to execute the following control sequence: in the embracing phase, inflating the bending airbag; in the tightening phase, inflating the inward contracting airbags a1 / a2; in the tapping phase, tapping the outward airbags b1 / b2 at a specific rhythm to inflate and deflate or control the wire drive module to retract and extend the wire; and in the release phase, releasing a specific amount of gas.

10. A control system for a bionic soft arm for a hugging robot according to claim 9, characterized in that, The control timing includes a delay phase before the embrace phase to maintain the constant air pressure of the flexion airbag for a first predetermined time; and a pause phase after the embrace phase to maintain the constant air pressure of the inner contraction airbags a1 / a2 for a second predetermined time.

Images