Telescopic mechanical arm structure with flexibility and rigidity adjusting capacity

Abstract

The invention discloses a telescopic mechanical arm structure with flexibility and rigidity adjusting ability, which comprises a first muscle pipeline sleeved with a first pneumatic muscle, a second muscle pipeline sleeved with a second pneumatic muscle, one end of the first muscle pipeline is fixedly connected with one end of the second muscle pipeline, and the other end of the first muscle pipeline is fixed on a base flange; the other end of the second muscle pipeline is connected with the through end of the second pneumatic muscle through the pipeline end cover, the through end of the first pneumatic muscle is fixed to the base flange, and the blocking end of the first pneumatic muscle and the blocking end of the second pneumatic muscle are oppositely arranged; the first muscle pipeline and the second muscle pipeline are arranged in the sleeve, and one end of the sleeve is fixed to the base flange. One end of the sliding cylinder is fixed to the tail end flange, the other end of the sliding cylinder is inserted into the sleeve, and the other end of the sliding cylinder, the blocking end of the first pneumatic muscle and the blocking end of the second pneumatic muscle are fixedly connected. The pneumatic muscles are oppositely arranged, so that double-side active movement and adjustment of the axial rigidity of the telescopic arm are achieved.

Description

Technical Field

[0001] The invention belongs to the field of robots and relates to the design of a telescopic mechanical arm structure with flexibility and rigidity adjustment capabilities. Background Art

[0002] With the rapid development of economy and the continuous progress of science and technology, the application of robotics has expanded from the traditional industrial manufacturing field to all aspects of daily life, including education, medical and service robots. Robots in these fields need to interact with people frequently, so higher requirements are placed on the flexibility and safety of robots. In order to meet these needs, soft robots have emerged. They use flexible materials as drivers and can move compliantly while ensuring the safety of human-machine interaction. The present invention aims to provide a flexible telescopic mechanical arm structure for a soft robot, which is used to provide axial linear motion freedom for the soft robot.

[0003] In traditional rigid robots, axial telescopic movement usually relies on linear motion components such as electric cylinders or pneumatic cylinders. Electric cylinders are driven by motors and lack flexibility, which poses a risk of safety interaction. Although pneumatic cylinders have a certain degree of flexibility due to air pressure drive, their pistons need to perform the dual tasks of sealing and movement at the same time, which will lead to severe wear in long-term operation, and the creeping phenomenon of the cylinders may also cause system instability. To this end, the present invention proposes a telescopic mechanical arm structure with flexibility and stiffness adjustment capabilities. Summary of the invention

[0004] The purpose of the present invention is to provide a telescopic mechanical arm structure with flexibility and stiffness adjustment capabilities to address the deficiencies of the prior art, so as to achieve bidirectional active motion and axial stiffness adjustment. The core idea of ​​the present invention is to use two pneumatic muscles to charge to achieve axial motion control. Bidirectional active telescopic motion can be achieved by inflating the muscles on both sides separately, and the axial stiffness can be regulated by adjusting the air pressure difference between the muscles on both sides.

[0005] The object of the present invention is achieved by the following technical solutions: a telescopic mechanical arm structure with flexibility and stiffness adjustment capability, comprising a base flange, a sleeve, a first muscle conduit, a second muscle conduit, a first pneumatic muscle, a second pneumatic muscle, a conduit end cap, a slide cylinder and an end flange;

[0006] The first muscle conduit is sleeved with a first pneumatic muscle, the second muscle conduit is sleeved with a second pneumatic muscle, one end of the first muscle conduit is fixedly connected to one end of the second muscle conduit, the other end of the first muscle conduit is fixed to the base flange, the other end of the second muscle conduit is connected to the through end of the second pneumatic muscle through a conduit end cover, the through end of the first pneumatic muscle is fixed to the base flange, and the blocked end of the first pneumatic muscle and the blocked end of the second pneumatic muscle are arranged opposite to each other;

[0007] The first muscle tube and the second muscle tube are arranged in the sleeve, and one end of the sleeve is fixed on the base flange; one end of the slide tube is fixed on the end flange, and the other end is inserted into the sleeve, and the other end of the slide tube, the blocking end of the first pneumatic muscle and the blocking end of the second pneumatic muscle are fixedly connected, which is used to transmit the axial movement of the pneumatic muscle to the slide tube, so that the slide tube performs axial movement.

[0008] Further, the pneumatic muscle comprises a through-end end cover, a through-end pressure head, a through-end head, a silicone tube, a braided mesh sleeve sleeved on the outside of the silicone tube, a plug, and a plug-end pressure head; the through-end head is provided with an air hole for filling air pressure into the silicone tube;

[0009] The through-end pressure head and the blocked-end pressure head are both provided with limiting grooves, and the two ends of the braided mesh sleeve are respectively installed in the limiting grooves of the through-end pressure head and the blocked-end pressure head, and the braided mesh sleeve sleeved on the outside of the silicone tube is used to limit the radial expansion of the silicone tube to achieve the axial extension of the pneumatic muscle;

[0010] One end of the silicone tube is sealed by pressing the through head and the through-end pressure head against each other (this end is the through end of the pneumatic muscle). Specifically, the through head is pressed into the silicone tube so that the silicone tube fits tightly against the through head, and the through-end pressure head presses the outer wall of the silicone tube; the other end is sealed by pressing the plug and the plug-end pressure head against each other (this end is the plug-end of the pneumatic muscle). Specifically, the plug is pressed into the silicone tube so that the silicone tube fits tightly against the plug, and the plug-end pressure head presses the outer wall of the silicone tube;

[0011] The through end cap of the first pneumatic muscle and the through head of the first pneumatic muscle cooperate to fix the through end of the first pneumatic muscle on the base flange.

[0012] Further, the through-end end cap of the first pneumatic muscle cooperates with the through-end head of the first pneumatic muscle, including:

[0013] The through head is provided with an external thread, and the through end cover is provided with a corresponding threaded hole, which is screwed together with the external thread provided on the through head.

[0014] Furthermore, the through-end pressure head and the blocking-end pressure head are both provided with square holes, and the through head and the blocking head are both provided with square shafts; the square hole of the through-end pressure head cooperates with the square shaft of the through head, and the square hole of the blocking-end pressure head cooperates with the square shaft of the blocking head, so as to maintain the same circumferential motion between the through-end pressure head and the through head, and between the blocking-end pressure head and the blocking head during the tightening process, and only retain the axial relative motion acting on the tightening.

[0015] Furthermore, the through-end pressure head and the blocking-end pressure head are both provided with step surfaces, and the through head and the blocking head are both provided with limiting surfaces; when pressed into place, the step surface of the through-end pressure head contacts the limiting surface of the through head, and the step surface of the blocking-end pressure head contacts the limiting surface of the blocking head, thereby achieving a limiting effect.

[0016] Furthermore, the through-end pressure head and the blocking-end pressure head are both provided with bite grooves for increasing the friction force and bite force during pressing; and / or

[0017] The through-end pressure head and the blocking-end pressure head are both provided with a flat surface for easy tightening; and / or

[0018] The through-head and the plug are both provided with arc surfaces for increasing the pressing effect.

[0019] Furthermore, the pneumatic muscle further comprises a blocking end cap and a blocking end nut;

[0020] The blocking end cover is provided with a connecting rod, and a corresponding slot is provided on the muscle tube 3 to provide movement space for the connecting rod extending from the blocking end cover;

[0021] The other end of the slide tube, the blocking end of the first pneumatic muscle and the blocking end of the second pneumatic muscle are fixedly connected, including: the other end of the slide tube, the blocking end cover of the first pneumatic muscle and the blocking end cover of the second pneumatic muscle are fixedly connected.

[0022] Furthermore, the plugging end cover is provided with a through hole; the plug is provided with an external thread, and the external thread portion thereof passes through the through hole of the plugging end cover and is fixed using a plugging nut to avoid unnecessary twisting of the silicone tube during assembly.

[0023] Further, the other end of the slide tube, the blocking end cover of the first pneumatic muscle and the blocking end cover of the second pneumatic muscle are fixedly connected, including:

[0024] The connecting rod on the blocking end cover of the first pneumatic muscle is provided with a first connecting hole connected to the slide cylinder, and the connecting rod on the blocking end cover of the second pneumatic muscle is provided with a second connecting hole connected to the slide cylinder; the other end of the slide cylinder is also provided with corresponding hole positions, and the bolt passes through the first connecting hole, the hole of the slide cylinder and the second connecting hole in turn and is tightened with the nut.

[0025] Furthermore, during installation, liquid raw tape is used to seal between the external thread and the corresponding threaded hole.

[0026] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0027] 1. Use pneumatic muscles as actuators to make the telescopic arm flexible.

[0028] 2. The muscles are used to drive the telescopic arm, so that both sides of the telescopic arm are actively moving, and the axial stiffness of the telescopic arm can be adjusted.

[0029] 3. Use square holes with threaded screws to achieve axial compression and sealing of the silicone tube and ensure that the pneumatic muscle can be easily installed and disassembled. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0031] Figure 1 An overall view of a telescopic arm provided in an embodiment of the present invention.

[0032] Figure 2 Exploded view of the telescopic arm.

[0033] Figure 3 Overall cross-sectional view of the telescopic arm.

[0034] Figure 4 Detailed diagram of pneumatic muscles.

[0035] Figure 5 Pneumatic muscle exploded view.

[0036] Figure 6 Pneumatic muscle cutaway.

[0037] Figure 7 Detailed schematic diagram of the pneumatic muscle access.

[0038] Figure 8 Schematic diagram of telescopic arm movement.

[0039] Telescopic arm main structure:

[0040] 1. Base flange; 2. Sleeve; 3. Muscle pipe (3A / 3B); 4. Pneumatic muscle (4A / 4B); 5. Pipe end cap

[0041] 6. Slide; 7. End flange;

[0042] The structure of pneumatic muscle 4:

[0043] 41. Through-end end cap; 42. Pressure head (42A / 42B); 43. Through-end cap; 44. Silicone tube; 45. Braided mesh sleeve; 46. Plug; 47. Plug-end end cap; Connecting rod 471; 48. Plug-end nut;

[0044] Some matching structures:

[0045] 411. threaded hole; 421. limiting groove; 422. plane; 423. square hole; 424. bite groove; 425. step surface;

[0046] 431. External thread; 432. Square shaft; 433. Limiting surface; 434. Air hole. DETAILED DESCRIPTION

[0047] The present invention is described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the features of the following embodiments and implementations can be combined with each other.

[0048] A telescopic mechanical arm structure with flexibility and rigidity adjustment capability of the present invention comprises a base flange, a sleeve, a first muscle pipeline, a second muscle pipeline, a first pneumatic muscle, a second pneumatic muscle, a pipeline end cover, a slide cylinder and an end flange;

[0049] The first muscle conduit is sleeved with a first pneumatic muscle, the second muscle conduit is sleeved with a second pneumatic muscle, one end of the first muscle conduit is fixedly connected to one end of the second muscle conduit, the other end of the first muscle conduit is fixed to the base flange, the other end of the second muscle conduit is connected to the through end of the second pneumatic muscle through a conduit end cover, the through end of the first pneumatic muscle is fixed to the base flange, and the blocked end of the first pneumatic muscle and the blocked end of the second pneumatic muscle are arranged opposite to each other;

[0050] The first muscle tube and the second muscle tube are arranged in the sleeve, one end of which is fixed on the base flange; one end of the slide is fixed on the end flange, and the other end is inserted into the sleeve, and the other end of the slide, the blocking end of the first pneumatic muscle and the blocking end of the second pneumatic muscle are fixedly connected, so as to transmit the axial movement of the pneumatic muscle to the slide, so that the slide moves axially. When different air pressures are respectively charged into the first pneumatic muscle and the second pneumatic muscle, the first pneumatic muscle and the second pneumatic muscle move axially, thereby driving the slide to move axially, that is, the mechanical arm performs telescopic movement.

[0051] Embodiment 1:

[0052] The muscle sealing method in the embodiment of the present invention adopts the idea of ​​threaded tightening and inclined surface pressing to ensure good sealing and convenience during installation and disassembly. The pneumatic muscle structure in the present invention is manufactured using light-curing 3D printing technology, which not only improves the flexibility of processing, reduces weight, but also helps cost control. The outer sleeve and slide are made of metal and are assembled with fixed connectors and other components.

[0053] See also Figure 1-Figure 8 The main structure of the telescopic arm in the embodiment of the present invention is mainly composed of the following parts: base flange 1, sleeve 2, muscle pipe 3, pneumatic muscle 4, pipe end cover 5, slide 6 and end flange 7. Among them, the muscle pipe 3 and the pneumatic muscle 4 are composed of two sets of identical structures, which are marked in the form of 3A, 3B and 4A, 4B in the figure. The muscle pipe 3A is the first muscle pipe, the muscle pipe 3B is the second muscle pipe, the pneumatic muscle 4A is the first pneumatic muscle, and the pneumatic muscle 4B is the second pneumatic muscle.

[0054] The pneumatic muscle 4 as a driver is mainly composed of the following parts: a through-end cap 41, a pressure head 42, a through-end cap 43, a silicone tube 44, a braided mesh sleeve 45, a plug 46, a plug end cap 47 and a plug end nut 48. The pressure head 42 has the same structure at both ends of the through-end cap and the plug end cap, which are marked as 42A and 42B in the figure. The pressure head 42A is the through-end pressure head, and the pressure head 42B is the plug end pressure head.

[0055] The movement of the pneumatic muscle in the embodiment of the present invention is mainly achieved by filling the silicone tube 44 with air pressure and limiting the radial expansion of the silicone tube 44 by the braided mesh sleeve 46 on the outside of the silicone tube 44 to achieve the axial extension of the pneumatic muscle. The braided mesh sleeve 46 will be limited by the limit groove 421 on the outside of the pressure head 42 to prevent the two ends of the braided mesh sleeve 46 from sliding off during movement. The seal between the silicone tube 44 and the main structure is mainly achieved by pressing the through head 43, the plug 46 and the respective pressure heads 42A and 42B against each other. A threaded hole 411 is left on the through end cover 41 for matching and tightening with the external thread 431 set on the through head 43. At the same time, a square hole 423 is left on the pressure head 42 to match and limit with the square shaft 432 on the through head 43. A flat surface 422 is also left on the outside of the pressure head 42 to facilitate tightening with tools such as wrenches. In this way, it is ensured that the main structures of the pressure head 42 and the through head 43 used to compress the silicone tube maintain the same circumferential motion during the tightening process, and only the axial relative motion acting on the compression is retained. In order to prevent the silicone tube 44 from being damaged due to excessive squeezing during muscle compression, a step surface 425 is designed on the pressure head 42 for limiting during compression. When the compression is in place, the limiting surface 433 on the through head 43 will contact the step surface 425 of the pressure head 42 to achieve a limiting effect. In order to achieve a better compression effect and prevent the silicone tube 44 from loosening, a tightly arranged bite groove 424 is provided on the inner wall of the pressure head 42 to increase the friction and bite force during compression. The part used for compression on the through head 43 is designed as an arc surface to achieve a better compression effect. A similar structure is also set at the plug end on the other side for sealing the silicone tube 44, except that the external thread on one side of the plug 46 is left longer, and the plug nut 48 is used to fix it after passing through the through hole on the plug end cover 47. In this way, it is not necessary to tighten the whole structure by rotating it during the final assembly, thereby avoiding unnecessary twisting of the silicone tube 44. In order to ensure the airtightness of the structure during actual installation, liquid raw tape will be used to seal between the threaded hole 411 and the external thread 431. In addition, the pneumatic muscle in the present invention uses air pressure as a power source. The driving air pressure will be connected to the through-end end caps 41 of the pneumatic muscles 4 on both sides through the air pipe and filled into the silicone tube 44 through the air holes 434 reserved inside the through head to realize the movement of a single muscle.

[0056] The movement of the telescopic arm as a whole is realized by respectively charging different air pressures p1 and p2 into the pneumatic muscles 4A and 4B on both sides to realize the axial telescopic movement. The corresponding hole position connected to the slide 6 is reserved on the end cover 47, and the pneumatic muscle as a whole is connected to the sleeve 2 through the base flange 1, and finally realizes the axial telescopic movement of the slide 6 relative to the sleeve 2. A muscle pipe 3 is designed on the outside of the pneumatic muscle 4 to further restrict the pneumatic muscle 4 to prevent it from producing unexpected deformation and buckling due to its own flexibility during the inflation process. At the same time, the muscle pipe 3 cooperates with the pipe end cover 5 to also play the role of fixing the pneumatic muscle as a whole to the base flange 1. For the convenience of installation, the muscle pipe 3 is designed as a symmetrically distributed structure, and 3A and 3B are connected by bolts. At the same time, in order to transmit the movement inside the muscle pipe 3 to the external slide 6, a corresponding slot is also set on the muscle pipe 3 to provide movement space for the connecting rod 471 extending from the end cover 47. At the same time, the axial stiffness of the telescopic arm is regulated by adjusting the air pressures p1 and p2 charged into the pneumatic muscles 4 on both sides.

[0057] It should be noted that the device embodiment shown in this embodiment matches the content of the above method embodiment, and the content of the above method embodiment can be referred to, which will not be repeated here.

[0058] The above embodiments are only used to illustrate the design ideas and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. The protection scope of the present invention is not limited to the above embodiments. Therefore, any equivalent changes or modifications made based on the principles and design ideas disclosed by the present invention are within the protection scope of the present invention.

Claims

1. A telescopic mechanical arm structure with flexibility and stiffness adjustment capability, characterized in that: It includes a base flange, a sleeve, a first muscle pipe, a second muscle pipe, a first pneumatic muscle, a second pneumatic muscle, a pipe end cap, a slide tube and an end flange; The first muscle conduit is sleeved with a first pneumatic muscle, the second muscle conduit is sleeved with a second pneumatic muscle, one end of the first muscle conduit is fixedly connected to one end of the second muscle conduit, the other end of the first muscle conduit is fixed to the base flange, the other end of the second muscle conduit is connected to the through end of the second pneumatic muscle through a conduit end cap, and the through end of the first pneumatic muscle is fixed to the base flange; The first muscle tube and the second muscle tube are arranged in the sleeve, and one end of the sleeve is fixed on the base flange; one end of the slide tube is fixed on the end flange, and the other end is inserted into the sleeve, and the other end of the slide tube, the blocking end of the first pneumatic muscle and the blocking end of the second pneumatic muscle are fixedly connected, so as to transmit the axial movement of the pneumatic muscle to the slide tube, so that the slide tube performs axial movement; the pneumatic muscle is driven by charging, so that both sides of the telescopic arm are actively moved, and the axial stiffness of the telescopic arm can be regulated.

2. A telescopic mechanical arm structure with flexibility and stiffness adjustment capability according to claim 1, characterized in that: The pneumatic muscle includes a through-end end cover, a through-end pressure head, a through-end head, a silicone tube, a braided mesh sleeve sleeved on the outside of the silicone tube, a plug, and a plug-end pressure head; the through-end head is provided with an air hole for filling air pressure into the silicone tube; The through-end pressure head and the blocked-end pressure head are both provided with limiting grooves, and the two ends of the braided mesh sleeve are respectively installed in the limiting grooves of the through-end pressure head and the blocked-end pressure head, and the braided mesh sleeve sleeved on the outside of the silicone tube is used to limit the radial expansion of the silicone tube to achieve the axial extension of the pneumatic muscle; One end of the silicone tube is sealed by pressing the through-end pressure head against each other, and the other end is sealed by pressing the plug against the end pressure head against each other; The through end cap of the first pneumatic muscle and the through head of the first pneumatic muscle cooperate to fix the through end of the first pneumatic muscle on the base flange.

3. A telescopic mechanical arm structure with flexibility and stiffness adjustment capability according to claim 2, characterized in that: The through-end end cap of the first pneumatic muscle cooperates with the through-end head of the first pneumatic muscle, including: The through head is provided with an external thread, and the through end cover is provided with a corresponding threaded hole, which is screwed together with the external thread provided on the through head.

4. A telescopic mechanical arm structure with flexibility and stiffness adjustment capability according to claim 2, characterized in that: The through-end pressure head and the blocking-end pressure head are both provided with square holes, and the through head and the blocking head are both provided with square shafts; the square hole of the through-end pressure head cooperates with the square shaft of the through head, and the square hole of the blocking-end pressure head cooperates with the square shaft of the blocking head, so as to maintain the same circumferential motion between the through-end pressure head and the through head, and between the blocking-end pressure head and the blocking head during the tightening process, and only retain the axial relative motion acting on the tightening.

5. A telescopic mechanical arm structure with flexibility and stiffness adjustment capability according to claim 2, characterized in that: The through-end pressure head and the blocking-end pressure head are both provided with step surfaces, and the through head and the blocking head are both provided with limiting surfaces; when pressed into place, the step surface of the through-end pressure head contacts the limiting surface of the through head, and the step surface of the blocking-end pressure head contacts the limiting surface of the blocking head, thereby achieving a limiting effect.

6. A telescopic mechanical arm structure with flexibility and stiffness adjustment capability according to claim 2, characterized in that: The through-end pressure head and the blocking-end pressure head are both provided with a bite groove for increasing the friction force and the bite force during pressing; and / or The through-end pressure head and the blocking-end pressure head are both provided with a flat surface for easy tightening; and / or The through-head and the plug are both provided with arc surfaces for increasing the pressing effect.

7. A telescopic mechanical arm structure with flexibility and stiffness adjustment capability according to claim 2, characterized in that: The pneumatic muscle also includes a plugging end cap and a plugging end nut; The blocking end cover is provided with a connecting rod, and a corresponding slot is provided on the muscle tube 3 to provide movement space for the connecting rod extending from the blocking end cover; The other end of the slide tube, the blocking end of the first pneumatic muscle and the blocking end of the second pneumatic muscle are fixedly connected, including: the other end of the slide tube, the blocking end end cover of the first pneumatic muscle and the blocking end end cover of the second pneumatic muscle are fixedly connected.

8. A telescopic mechanical arm structure with flexibility and stiffness adjustment capability according to claim 7, characterized in that: The plugging end cover is provided with a through hole; the plug is provided with an external thread, and the external thread portion thereof passes through the through hole of the plugging end cover and is fixed using a plugging nut to avoid unnecessary twisting of the silicone tube during assembly.

9. A telescopic mechanical arm structure with flexibility and stiffness adjustment capability according to claim 7, characterized in that: The other end of the slide tube, the blocking end cover of the first pneumatic muscle and the blocking end cover of the second pneumatic muscle are fixedly connected, including: The connecting rod on the blocking end cover of the first pneumatic muscle is provided with a first connecting hole connected to the slide cylinder, and the connecting rod on the blocking end cover of the second pneumatic muscle is provided with a second connecting hole connected to the slide cylinder; the other end of the slide cylinder is also provided with corresponding hole positions, and the bolt passes through the first connecting hole, the hole of the slide cylinder and the second connecting hole in turn and is tightened with the nut.

10. A telescopic mechanical arm structure with flexibility and stiffness adjustment capability according to claim 3 or 7, characterized in that: During installation, liquid raw tape is used to seal between the external thread and the corresponding threaded hole.

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