A device and method for manufacturing and testing a foldable pneumatic artificial muscle

Abstract

The application discloses a kind of folding pneumatic artificial muscle production test integration device and method;The device includes base, displacement mechanism, controller and two end forming mechanisms.Displacement mechanism includes fixed block, guide pillar, screw rod, displacement drive motor, screw opening and closing component and sliding block.Fixed block and guide pillar are fixed on base.Sliding block is slidably connected on guide pillar.Screw rod is rotatably connected on base, and is driven by displacement drive motor.Two end forming mechanisms are respectively installed on fixed block and sliding block.The present application can realize the integration of pneumatic artificial muscle production, mechanical property and displacement performance test by the screw rod mechanism capable of combination-separation switching, force sensor and displacement sensor, and measures the force output and deformation displacement of artificial muscle while completing the production of pneumatic artificial muscle.

Description

Technical Field

[0001] This invention belongs to the field of pneumatic artificial muscle fabrication and testing, specifically relating to the field of pneumatic artificial muscle performance testing and packaging. Background Technology

[0002] The aging population wave of the 21st century will sweep the globe, posing severe challenges to social development. As of 2018, my country had over 250 million people aged 60 and above. Due to the decline in muscle strength, the elderly experience varying degrees of decreased walking ability. To improve the walking ability of the elderly and prevent injuries from falls, assistive devices have emerged, among which exoskeletons are a popular choice. Because rigid exoskeletons restrict the body's freedom of movement, flexible exoskeletons have become a research hotspot. Flexible exoskeletons require actuators with good flexibility to provide power, and pneumatic artificial muscles are a good option. The folded pneumatic artificial muscle of this invention is made of folded polyacrylamide material, possessing flexibility, airtightness, and non-stretchability. The folding ratio of the pneumatic artificial muscle is the ratio of the folded length to the total length, i.e., Fr = Wf / W0. Through geometric control, that is, changing the folding ratio of the pneumatic artificial muscle, its performance can be altered. Experimental tests show that when the folding ratio Fr = 0.67, the actuator almost fully expands, contracts axially, and expands radially, resulting in less volume loss while maintaining good force output. With the widespread application of pneumatic artificial muscles, the requirements for their fabrication and performance are becoming increasingly urgent and stringent. Currently, testing pneumatic artificial muscles requires setting up experimental platforms, which is cumbersome, and there is no integrated experimental device for fabrication and performance testing. Different experiments require different platforms, and post-experiment cleanup is necessary, consuming considerable time and effort from the experimenter. Force output and deformation displacement are two important indicators for evaluating the performance of pneumatic artificial muscles, and using sensors can significantly reduce the workload of the experimenter. Therefore, an integrated fabrication and testing device for foldable pneumatic artificial muscles is crucial. Summary of the Invention

[0003] The purpose of this invention is to provide an integrated device for the fabrication and testing of foldable pneumatic artificial muscles.

[0004] This integrated device for fabricating and testing foldable pneumatic artificial muscles includes a base, a displacement mechanism, a controller, and two end-forming mechanisms. The displacement mechanism comprises a fixed block, a guide post, a lead screw, a displacement drive motor, a threaded opening and closing assembly, and a sliding block. The fixed block and guide post are both fixed to the base. The sliding block is slidably connected to the guide post. The lead screw is rotatably connected to the base and driven by the displacement drive motor. The two end-forming mechanisms are respectively mounted on the fixed block and the sliding block.

[0005] A threaded engagement / disengagement assembly is provided between the sliding block and the lead screw. This assembly controls the threaded connection or disengagement of the sliding block and the lead screw. The end forming mechanism includes a servo motor, a traction wheel, a forming base, a housing, and a movable tendon. The forming base is fixed to the top of the corresponding fixed block or sliding block. The housing is fixed to the forming base. The traction wheel is rotatably connected inside the housing and is driven to rotate by the servo motor.

[0006] The molding base has an elongated artificial muscle mounting groove and a U-shaped clearance groove. The relative positions of the artificial muscle mounting groove and the U-shaped clearance groove create a U-shaped beam structure with one end suspended in the molding base. The bottom and top of the U-shaped beam structure have a first through hole and a second through hole, respectively; the first through hole communicates with the bottom of the artificial muscle mounting groove, and the second through hole communicates with the top of the artificial muscle mounting groove.

[0007] All movable tendons are made of drawstring; the two ends of each tendon are a winding end and a free end, respectively. During operation, the winding ends of both tendons are fixed to the outer circumference of the traction wheel. One tendon passes through the first through-hole and extends into the artificial muscle mounting slot. The other tendon bypasses the suspended section of the U-shaped beam structure, passes through the second through-hole, and extends into the artificial muscle mounting slot. The free ends of both tendons are fixed to the opening edge of the pneumatic artificial muscle. The free ends of the two tendons are symmetrical about the central axis of the pneumatic artificial muscle.

[0008] The artificial muscle mounting slot is equipped with a heating strip capable of lifting and lowering; the heating strip can squeeze and heat the end opening of the pneumatic artificial muscle located in the artificial muscle mounting slot, thereby closing the end opening of the pneumatic artificial muscle.

[0009] Preferably, the sliding block has a mounting groove. The lead screw passes through the mounting groove. The threaded opening and closing assembly includes two semi-threaded opening and closing blocks, two first electromagnets, and two second magnets. The two semi-threaded opening and closing blocks are slidably connected in the mounting groove, and each of their opposite sides has a semi-threaded groove. When the two semi-threaded opening and closing blocks are joined together, the two semi-threaded grooves together form a threaded hole that constitutes a helical pair with the lead screw. The semi-threaded opening and closing blocks are made of ferromagnetic material. The opposite sides of the two semi-threaded opening and closing blocks are respectively provided with mutually matching first electromagnets and slots. The two second electromagnets are respectively fixed on two opposite sidewalls of the mounting groove. The two second electromagnets are respectively located on opposite sides of the two semi-threaded opening and closing blocks.

[0010] Preferably, the servo motor is fixed to the housing. The output shaft of the servo motor is fixed to the traction wheel by a flange and bolts.

[0011] Preferably, the second through hole is located on the side of the first through hole away from the suspended end of the U-shaped beam structure. The active tendon passing through the second through hole connects to the edge of the pneumatic artificial muscle opening closest to the suspended end of the U-shaped beam structure; the active tendon passing through the first through hole connects to the edge of the pneumatic artificial muscle opening furthest from the suspended end of the U-shaped beam structure.

[0012] Preferably, the bottom of the U-shaped beam structure is provided with a guide boss; the longitudinal section of the guide boss is semi-circular and located on the side of the first through hole near the cantilevered end of the U-shaped beam structure. The active tendon passes around the guide boss before passing through the first through hole.

[0013] Preferably, the heating strip is provided with multiple heating plates; the heating plates are used to increase the surface temperature of the heating strip after power is applied. The length of the heating strip is greater than the width of the pneumatic artificial muscle in its initial state.

[0014] Preferably, the integrated fabrication and testing device for the foldable pneumatic artificial muscle also includes a detection module. The detection module includes a force sensor and a displacement sensor. The force sensor is mounted between the sliding block and its corresponding outer casing. The displacement sensor, employing a laser rangefinder, is mounted on the sliding block and faces the fixed block.

[0015] Preferably, the molded base includes a second reversing post and a first reversing post. One movable tendon bypasses the first reversing post; the other movable tendon bypasses the second reversing post.

[0016] Secondly, the present invention provides a method for fabricating and testing a foldable pneumatic artificial muscle, employing the aforementioned integrated fabrication and testing device; the method for fabricating and testing a foldable pneumatic artificial muscle includes the following steps:

[0017] Step 1: Compress the pneumatic artificial muscle with open ends into a flat shape and pass it through the artificial muscle mounting slots in the two end forming mechanisms.

[0018] Step 2: Attach the free end of the movable tendon to the opening of the pneumatic artificial muscle; fix the coiled end of the movable tendon to the traction wheel.

[0019] Step 3: Switch the threaded opening and closing assembly to the state of engagement with the lead screw; adjust the distance between the two end forming mechanisms by rotating the lead screw to straighten the pneumatic artificial muscle; rotate the traction wheel to drive the active tendon to retract; the active tendon pulls the edge of the pneumatic artificial muscle to deform towards the center, so that the pneumatic artificial muscle forms a folded structure with a preset folding ratio.

[0020] Step 4: The heating strip heats and compresses the pneumatic artificial muscle, closing the openings at both ends of the pneumatic artificial muscle and maintaining its folded structure.

[0021] Step 5: Pressurize the pneumatic artificial muscle and test the tension of the foldable pneumatic artificial muscle on the end forming mechanism to obtain the tension-pressure relationship curve of the foldable pneumatic artificial muscle.

[0022] Step 6: Switch the threaded opening and closing assembly to the state of being separated from the lead screw, pressurize the pneumatic artificial muscle, detect the displacement of the sliding block under the pull of the foldable pneumatic artificial muscle, and obtain the displacement-pressure relationship curve of the foldable pneumatic artificial muscle.

[0023] Preferably, in steps five and six, if the obtained tension-pressure relationship curve and displacement-pressure relationship curve do not meet the requirements, the folding ratio is adjusted and steps one to four are repeated to prepare a new foldable pneumatic artificial muscle.

[0024] The beneficial effects of this invention are:

[0025] 1. This invention, through a lead screw mechanism capable of switching between engagement and disengagement, combined with force and displacement sensors, enables the integrated fabrication, mechanical performance, and displacement performance testing of pneumatic artificial muscles. It measures the force output and deformation displacement of the artificial muscle while completing the fabrication of the pneumatic artificial muscle.

[0026] 2. This invention can produce a series of pneumatic artificial muscles with different mechanical properties by changing the folding ratio of the pneumatic artificial muscle and by understanding the relationship between the calibrated folding ratio and force output and deformation displacement.

[0027] 3. This invention uses an electromagnet as the locking mechanism for the lead screw, enabling both force output and deformation displacement testing modes. When force output is required, the central electromagnet is energized while the two side electromagnets are de-energized, closing the support base and locking the slide table to the lead screw. When deformation displacement is required, the central electromagnet is de-energized while the two side electromagnets are energized, separating the support base, slide table, and lead screw. The slide table can then slide on the slide rod, allowing the deformation displacement to be measured. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0029] Figure 2 This is a cross-sectional view of the displacement mechanism and the end forming mechanism in this invention.

[0030] Figure 3 This is a schematic diagram of the molded base in this invention.

[0031] Figure 4 This is a schematic diagram showing the connection between the servo motor and the flange in this invention.

[0032] Figure 5 This is a schematic diagram showing the deformation of the pneumatic artificial muscle before and after inflation in this invention.

[0033] Figure 6 This is a schematic diagram showing the deformation of the pneumatic artificial muscle before and after inflation during testing in this invention.

[0034] Figure 7 This is a schematic diagram of the connection structure between the sliding block and the threaded opening and closing assembly in this invention.

[0035] Figure 8 This is a schematic diagram illustrating the fabrication of a non-foldable pneumatic artificial muscle into a foldable pneumatic artificial muscle in this invention.

[0036] Figure 9 This is a cross-sectional schematic diagram of the foldable pneumatic artificial muscle before and after inflation in this invention.

[0037] Figure 10 This is a cross-sectional schematic diagram of the three-layer folded pneumatic artificial muscle prepared in this invention. Detailed Implementation

[0038] The present invention will be further described below with reference to the accompanying drawings.

[0039] like Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown, a foldable pneumatic artificial muscle fabrication and testing integrated device includes a base 2, a displacement mechanism, a detection module, a controller, and two end forming mechanisms 3.

[0040] The displacement mechanism includes a fixed block 4, guide pillars 7, a lead screw 11, a displacement drive motor 6, a threaded opening and closing assembly, and a sliding block 10. Two horizontally positioned guide pillars 7 are fixed to the base 2. The fixed block 4 is fixed to one end of the top of the base 2. The sliding block 10 is slidably connected to the two guide pillars 7. The lead screw 11 is rotatably connected to the base 2. The displacement drive motor 6 is fixed to the base 2, and its output shaft is fixed to one end of the lead screw 11.

[0041] Two end forming mechanisms 3 are respectively mounted on the fixed block 4 and the sliding block 10. The detection module is used to detect the distance between the two end forming mechanisms 3, as well as the tension applied by the pneumatic artificial muscle to the end forming mechanism 3.

[0042] A threaded opening and closing assembly is provided between the sliding block 10 and the lead screw 11. The threaded opening and closing assembly is used to control the threaded connection or separation between the sliding block 10 and the lead screw 11. The sliding block 10 has a mounting groove. The lead screw 11 passes through the mounting groove. The threaded opening and closing assembly includes two semi-threaded opening and closing blocks 12, two first electromagnets 16, and two second magnets 15.

[0043] Two semi-threaded opening and closing blocks 12 are slidably connected in the mounting groove, and each of their opposite sides is provided with a semi-threaded groove. When the two semi-threaded opening and closing blocks 12 are spliced ​​together, the two semi-threaded grooves together form a threaded hole that constitutes a helical pair with the lead screw 11.

[0044] The semi-threaded opening and closing block 12 is made of a ferromagnetic material that can be attracted by a magnet. A first electromagnet 16 and a slot are respectively provided on the opposite sides of the two semi-threaded opening and closing blocks 12. The first electromagnet 16 is used to fix the two semi-threaded opening and closing blocks 12 together, so that the threaded opening and closing assembly can drive the sliding block 10 to move under the drive of the lead screw 11, adjusting the distance between the two end forming mechanisms 3.

[0045] Two second electromagnets 15 are fixed on two opposite side walls of the mounting groove. The two second electromagnets 15 are respectively arranged on opposite sides of the two semi-threaded opening and closing blocks 12, and are used to separate the two semi-threaded opening and closing blocks 12 from the lead screw 11 by magnetic force.

[0046] The end forming mechanism 3 includes a servo motor 1, a flange 17, a traction wheel 8, a forming base 5, and a housing 9. The forming base 5 is fixed to the top of the corresponding fixing block 4 or sliding block 10. The housing 9 is fixed to the forming base 5. The servo motor 1 is fixed to the housing 9. The traction wheel 8 is rotatably connected inside the housing 9. The output shaft of the servo motor 1 is fixed to the traction wheel 8 via the flange 17 and bolts.

[0047] An elongated artificial muscle mounting groove 5-1 and a U-shaped relief groove 5-2 are formed on the molding base 5. The artificial muscle mounting groove 5-1 is nested between the two transverse sections of the U-shaped relief groove 5-2, thus forming a U-shaped beam structure 5-3 in the molding base 5. The U-shaped relief groove 5-2 forms the outer wall of the U-shaped beam structure 5-3; the artificial muscle mounting groove 5-1 forms the inner wall of the U-shaped beam structure 5-3. The U-shaped relief groove 5-2 makes the arc-shaped connecting section of the U-shaped beam structure 5-3 suspended.

[0048] The U-shaped beam structure 5-3 has a first through hole 18 and a second through hole 20 at its bottom and top, respectively. The first through hole 18 communicates with the bottom of the artificial muscle mounting groove 5-1. The second through hole 20 communicates with the top of the artificial muscle mounting groove 5-1. The second through hole 20 is located on the side of the first through hole 18 away from the cantilevered end of the U-shaped beam structure 5-3. A guide boss is provided at the bottom of the U-shaped beam structure 5-3. The longitudinal section of the guide boss is semi-circular and is located on the side of the first through hole 18 near the cantilevered end of the U-shaped beam structure 5-3.

[0049] The molding base 5 is provided with a second reversing column 13 and a first reversing column 19. Both movable tendons 21 are made of drawstring; the two ends of each movable tendon 21 are a winding end and a free end, respectively; the winding ends of both movable tendons 21 are fixed to the outer circumference of the traction wheel 8; one movable tendon 21 bypasses the first reversing column 19, passes through the first through hole 18, and extends into the artificial muscle mounting groove 5-1. The other movable tendon 21 follows the U-shaped relief groove 5-2, bypasses the second reversing column 13, the suspended section of the U-shaped beam structure 5-3, and the guide boss, passes through the second through hole 20, and extends into the artificial muscle mounting groove 5-1.

[0050] The free ends of both movable tendons 21 can be fixed to the edge of the air bag opening of the artificial muscle being produced by bonding or other connection methods.

[0051] A heating strip 14 capable of vertical movement is installed within the artificial muscle mounting slot 5-1. This vertical movement compresses the open ends of the artificial muscle air bag, thermally sealing the edges of the openings. Multiple heating plates are provided on the outer surface of the heating strip 14 to increase its surface temperature. The length of the heating strip 14 is greater than the fully extended length of the pneumatic artificial muscle. As an optional technical solution, the raising of the heating strip 14 is driven by an electromagnet, and its lowering is achieved using a spring-loaded return mechanism.

[0052] The U-shaped beam structure 5-3 is made of high-temperature resistant material. Through heating and compression by the heating strip 14, adhesiveness is created at the opening of the pneumatic artificial muscle, allowing them to bond together. After heating for a few seconds, the heating strip 14 is turned off, and the muscles are allowed to cool, resulting in pneumatic artificial muscles with different folding ratios.

[0053] In this embodiment, the pneumatic artificial muscle is generally made of polyacrylamide, which exhibits good stability and tolerance under high temperature conditions. It has excellent thermal stability, maintaining high adhesive strength and bonding performance even at high temperatures. Furthermore, polyacrylamide also exhibits good mechanical properties, possessing certain strength and stability under high temperature and pressure.

[0054] The detection module includes a force sensor and a displacement sensor. The force sensor is installed between the sliding block 10 and its corresponding housing 9. The displacement sensor is a laser rangefinder sensor, installed on the sliding block 10 and facing the fixed block 4. The force sensor and displacement sensor acquire analog signals and perform analog-to-digital conversion through a data acquisition module; the resulting digital signals are output to the controller for processing and analysis.

[0055] During operation, a tubular pneumatic artificial muscle, open at both ends, is compressed into a double-layered flat shape and passed through the artificial muscle mounting slots 5-1 in the two end forming mechanisms 3. The free ends of the two movable tendons 21 in the end forming mechanism 3 are respectively bonded to the opposite ends of the same opening of the pneumatic artificial muscle. This allows the two movable tendons 21 to pull and deform the edges of the pneumatic artificial muscle opening, forming a folded structure. The folding ratio of the pneumatic artificial muscle can be changed by the amount of coiling of the movable tendons 21 by the traction wheel 8. With the help of force and displacement sensors, the mechanical properties and length changes of the pneumatic artificial muscle with different folding ratios under different input pressures can be detected. When detecting the mechanical properties and length changes of the pneumatic artificial muscle, a heating strip 14 is used to clamp the pneumatic artificial muscle, fixing it to the two end forming mechanisms 3.

[0056] The working method of this integrated device for fabricating and testing foldable pneumatic artificial muscles includes the following steps:

[0057] Step 1, as follows Figure 6 As shown, the ends of two movable tendons 21 are bonded to both openings of the pneumatic artificial muscle; the two tendon connection points on the same opening of the pneumatic artificial muscle are symmetrical about the axis of the pneumatic artificial muscle. The pneumatic artificial muscle passes through the artificial muscle mounting slots 5-1 on the two molded bases 5; the movable tendons 21 at both ends of the pneumatic artificial muscle are fixed to the two traction wheels 8 respectively. Specifically, the movable tendons 21 connected to the pneumatic artificial muscle pass through the corresponding through holes, around the corresponding guide posts, around the traction wheels 8 and are fixed.

[0058] Step two, as Figure 7 By inflating and pressurizing the pneumatic artificial muscle, the muscle expands, generating force output and deformation displacement. For example... Figure 7 When the force output needs to be measured, the first electromagnet 16 is energized to generate magnetic force, causing the semi-threaded opening and closing block 12 to engage with the lead screw 11. When the displacement drive motor 6 is energized, it drives the lead screw 11 to rotate, allowing the threaded opening and closing assembly to move on the lead screw 11. When the deformation displacement needs to be measured, the first electromagnet 16 is de-energized, and the second electromagnet 15 is energized. The semi-threaded opening and closing block 12 is attracted by the two second electromagnets 15, and the device opens. At this time, the threaded opening and closing assembly is not fixed to the lead screw 11. When the servo motor 1 is energized and rotates, it will generate deformation displacement following the change in the folding ratio, moving on the slide rod. When the folding ratio needs to be changed, the servo motor 1 is energized and started, driving the flange 17 to rotate and simultaneously achieving coaxial rotation, driving the traction wheel 8 to rotate. When the traction wheel 8 rotates counterclockwise, the edge of the pneumatic artificial muscle is pulled inward at the same rate, increasing the folding ratio of the pneumatic artificial muscle. After inflating inward, it contracts axially and expands radially. Figure 8As shown, the folding ratio is defined as Fr = Wf / W0. Different folding ratios result in different performance of the pneumatic artificial muscle. Wf is the width of the folded portion; W0 is the initial width in the folded state.

[0059] Step 3: Both servo motor 1 and the pressure control valve are connected to the computer via an Arduino Mega 2560 microcontroller, which can also transmit angle feedback in real time. Simultaneously with servo motor 1 powered on, the force sensor and displacement sensor are activated. After power-on, the traction wheel 8 rotates, and the folding ratio of the pneumatic artificial muscle changes over time. The force sensor and displacement sensor can directly measure the output force and deformation displacement when the threaded opening and closing assembly closes and opens, respectively. The data signals are output to the computer for processing and analysis, generating curves. The relationship between different folding ratios and strain and strain force can then be observed.

[0060] Step four: When creating a pneumatic artificial muscle, after the above operations, adjust the inflated pneumatic artificial muscle 22 to the desired fold ratio, then turn on the heating strip 14. The surface temperature of the heating strip 14 rises, causing the pneumatic artificial muscle to become adhesive. Then turn off the heating strip 14 and allow it to cool down, after which the pneumatic artificial muscle adheres to the surface. The pneumatic artificial muscle with the changed fold ratio is then complete. The motor operates at different times to produce different fold ratios, which can be controlled by a microcontroller. This allows for the creation of pneumatic artificial muscles with different fold ratios and the testing of their performance.

[0061] The cross-sectional changes of the fabricated foldable pneumatic artificial muscle during inflation and expansion are as follows: Figure 9 As shown; furthermore, the present invention connects the movable tendon passing through the second through hole 20 to the edge of the pneumatic artificial muscle opening closest to the suspended end of the U-shaped beam structure; the movable tendon passing through the first through hole 18 connects to the edge of the pneumatic artificial muscle opening furthest from the suspended end of the U-shaped beam structure; thus, the concave folded area of ​​the pneumatic artificial muscle can be pulled inward to an overlapping degree, such as... Figure 10 As shown, a multi-layered folded pneumatic artificial muscle was obtained.

Claims

1. A foldable pneumatic artificial muscle fabrication and testing integrated device; comprising a base (2) and a displacement mechanism; characterized in that: It also includes two end forming mechanisms (3); the displacement mechanism includes a fixed block (4), a guide post (7), a lead screw (11), a displacement drive motor (6), a threaded opening and closing assembly, and a sliding block (10); the fixed block (4) and the guide post (7) are both fixed on the base (2); the sliding block (10) is slidably connected to the guide post (7); the lead screw (11) is rotatably connected to the base (2) and driven by the displacement drive motor (6); the two end forming mechanisms (3) are respectively installed on the fixed block (4) and the sliding block (10); A threaded opening and closing assembly is provided between the sliding block (10) and the lead screw (11); the threaded opening and closing assembly is used to control the threaded connection or separation of the sliding block (10) and the lead screw (11); the end forming mechanism (3) includes a servo motor (1), a traction wheel (8), a forming base (5), a housing (9) and a movable tendon (21); the forming base (5) is fixed on the top of the corresponding fixed block (4) or the sliding block (10); the housing (9) is fixed on the forming base (5); the traction wheel (8) is rotatably connected to the inside of the housing (9) and is driven to rotate by the servo motor (1); The molding base (5) is provided with an elongated artificial muscle mounting groove (5-1) and a U-shaped relief groove (5-2); the relative positions of the artificial muscle mounting groove (5-1) and the U-shaped relief groove (5-2) make a U-shaped beam structure (5-3) with one end suspended in the molding base (5); the bottom and top of the U-shaped beam structure (5-3) are respectively provided with a first through hole (18) and a second through hole (20); the first through hole (18) is connected to the bottom of the artificial muscle mounting groove (5-1); the second through hole (20) is connected to the top of the artificial muscle mounting groove (5-1); The active tendons (21) are all made of draw wire; the two ends of the active tendons (21) are the winding end and the free end, respectively; during operation, the winding ends of the two active tendons (21) are fixed to the outer circumference of the traction wheel (8); one of the active tendons (21) passes through the first through hole (18) and extends into the artificial muscle mounting groove (5-1); the other active tendon (21) passes around the suspended section of the U-shaped beam structure (5-3) and passes through the second through hole (20) and extends into the artificial muscle mounting groove (5-1); the free ends of the two active tendons (21) are fixed to the opening edge of the pneumatic artificial muscle; the free ends of the two active tendons (21) are symmetrical about the central axis of the pneumatic artificial muscle. The artificial muscle mounting groove (5-1) is equipped with a heating strip (14) capable of lifting and lowering; the heating strip (14) can squeeze and heat the end opening of the pneumatic artificial muscle in the artificial muscle mounting groove (5-1), so that the end opening of the pneumatic artificial muscle is closed.

2. The integrated device for fabrication and testing of foldable pneumatic artificial muscles according to claim 1, characterized in that: The sliding block (10) is provided with an installation groove; the lead screw (11) passes through the installation groove; the threaded opening and closing assembly includes two semi-threaded opening and closing blocks (12), two first electromagnets (16) and two second electromagnets (15); the two semi-threaded opening and closing blocks (12) are slidably connected in the installation groove, and semi-threaded grooves are provided on opposite sides; when the two semi-threaded opening and closing blocks (12) are spliced ​​together, the two semi-threaded grooves surround to form a threaded hole that forms a helical pair with the lead screw (11); the semi-threaded opening and closing blocks (12) are made of ferromagnetic material; the opposite sides of the two semi-threaded opening and closing blocks (12) are respectively provided with matching first electromagnets (16) and slots; the two second electromagnets (15) are respectively fixed on the two opposite side walls of the installation groove; the two second electromagnets (15) are respectively located on the opposite sides of the two semi-threaded opening and closing blocks (12).

3. The integrated device for fabrication and testing of foldable pneumatic artificial muscles according to claim 1, characterized in that: The servo motor (1) is fixed on the housing (9); the output shaft of the servo motor (1) is fixed to the traction wheel (8) by a flange (17) and bolts.

4. The integrated device for fabrication and testing of foldable pneumatic artificial muscles according to claim 1, characterized in that: The second through hole (20) is located on the side of the first through hole (18) away from the suspended end of the U-shaped beam structure (5-3); the active tendon passing through the second through hole is connected to the edge of the pneumatic artificial muscle opening closest to the suspended end of the U-shaped beam structure; the active tendon passing through the first through hole is connected to the edge of the pneumatic artificial muscle opening furthest from the suspended end of the U-shaped beam structure.

5. The integrated device for fabrication and testing of a foldable pneumatic artificial muscle according to claim 1, characterized in that: The bottom of the U-shaped beam structure (5-3) is provided with a guide boss; the longitudinal section of the guide boss is semi-circular and located on the side of the first through hole (18) near the suspended end of the U-shaped beam structure (5-3); the active tendon (21) passes through the first through hole (18) and bypasses the guide boss.

6. The integrated device for fabrication and testing of a foldable pneumatic artificial muscle according to claim 1, characterized in that: The heating strip (14) is provided with multiple heating plates; the heating plates are used to raise the surface temperature of the heating strip (14) after being powered on; the length of the heating strip (14) is greater than the width of the pneumatic artificial muscle in the initial state.

7. The integrated device for fabrication and testing of foldable pneumatic artificial muscles according to claim 1, characterized in that: The integrated device for manufacturing and testing foldable pneumatic artificial muscles also includes a detection module; the detection module includes a force sensor and a displacement sensor; the force sensor is installed between the sliding block (10) and its corresponding outer shell (9); the displacement sensor is a laser rangefinder sensor, installed on the sliding block (10) and facing the fixed block (4).

8. The integrated device for fabrication and testing of foldable pneumatic artificial muscles according to claim 1, characterized in that: The molding base (5) is provided with a second reversing column (13) and a first reversing column (19); one movable tendon (21) passes around the first reversing column (19); and another movable tendon (21) passes around the second reversing column (13).

9. A method for fabricating and testing foldable pneumatic artificial muscles, characterized in that: The device for fabricating and testing a foldable pneumatic artificial muscle as described in claim 1 is used; the method for fabricating and testing the foldable pneumatic artificial muscle includes the following steps: Step 1: Compress the pneumatic artificial muscle with open ends into a flat shape and pass it through the artificial muscle mounting slot (5-1) in the two end forming mechanisms (3). Step 2: Adhere the free end of the active tendon (21) to the opening of the pneumatic artificial muscle; fix the coiled end of the active tendon (21) to the traction wheel (8); Step 3: Switch the threaded opening and closing assembly to the state of being engaged with the lead screw (11); adjust the distance between the two end forming mechanisms (3) by rotating the lead screw (11) so that the pneumatic artificial muscle is straightened; rotate the traction wheel (8) to drive the active tendon (21) to coil; the active tendon (21) pulls the edge of the pneumatic artificial muscle to deform towards the center so that the pneumatic artificial muscle forms a folded structure with a preset folding ratio; Step 4: Heating strip (14) heats and squeezes the pneumatic artificial muscle, so that the openings at both ends of the pneumatic artificial muscle are closed and the folded structure is maintained; Step 5: Pressurize the pneumatic artificial muscle and test the tension of the foldable pneumatic artificial muscle on the end forming mechanism (3) to obtain the tension-pressure relationship curve of the foldable pneumatic artificial muscle. Step 6: Switch the threaded opening and closing assembly to the state of being separated from the lead screw (11), pressurize the pneumatic artificial muscle, detect the displacement of the sliding block (10) under the pull of the folded pneumatic artificial muscle, and obtain the displacement-pressure relationship curve of the folded pneumatic artificial muscle.

10. The method for fabricating and testing a foldable pneumatic artificial muscle according to claim 9, characterized in that: If the obtained tension-pressure relationship curve and displacement-pressure relationship curve do not meet the requirements in steps five and six, the preset folding ratio is adjusted and steps one to four are repeated to prepare a new foldable pneumatic artificial muscle.

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