Driving and control integrated structure pneumatic artificial muscle with self-sensing function

Abstract

The invention provides a driving and control integrated structure pneumatic artificial muscle with a self-sensing function. The driving and control integrated structure pneumatic artificial muscle comprises an upper end connecting piece, a main cavity and a lower end connecting piece. The upper end connecting piece is fixed to the top end of the main cavity, the lower end connecting piece is fixed to the bottom end of the main cavity, and the upper end connecting piece and the lower end connecting piece are connected with the main cavity through zigzag triangular lines so as to ensure assembly and air tightness of the pneumatic artificial muscle. According to the invention, acquisition, processing, driving and control integration and self-sensing functions of air pressure, deformation quantity and other signals of the pneumatic artificial muscle are realized. Meanwhile, parameters such as displacement, strain and pressure of the muscle are monitored in real time, an external sensor is not needed, compared with traditional pneumatic artificial muscle, the complexity, cost and size of a control system are reduced, the problem that the state of the muscle cannot be directly reflected due to the influence of the sensor position is solved, more accurate closed-loop control is achieved, and the reliability of the system is improved. And meanwhile, the application scene of the pneumatic artificial muscle under the conditions of limited space and the like is expanded.

Description

Technical Field

[0001] The present invention belongs to the field of bionic mechanical equipment, and particularly relates to a drive and control integrated pneumatic artificial muscle with self-sensing function. Background Art

[0002] The pneumatic artificial muscle is small in volume and light in weight, suitable for installation in equipment with limited space, and will not cause a burden on the overall system. It has a soft characteristic and can safely contact humans or other sensitive objects, reducing potential injuries caused by rigid machinery. At the same time, its working principle is simple and it can be driven by compressed air.

[0003] In addition, the pneumatic muscle can also be used as a driver in soft robot equipment.

[0004] At the same time, traditional pneumatic artificial muscles need to be used in conjunction with sensors to achieve the simplest closed-loop control effect in applications. However, in the actual application process, the setting of external sensors is restricted due to the actual application environment of the pneumatic muscle. For example, the application space is small and there is no installation space for external sensors. Secondly, the setting of external sensors usually affects the application effect of the pneumatic muscle. For example, for a robotic arm driven by a pneumatic muscle, the load of the robotic arm is greatly increased due to the installation of external sensors, increasing the usage limitations of the pneumatic artificial muscle. Summary of the Invention

[0005] Aiming at the deficiencies in the prior art, the purpose of the present invention is to provide a drive and control integrated pneumatic artificial muscle with self-sensing function, which can achieve the closed-loop control effect of cascade multi-loop of the pneumatic artificial muscle and reduce the influence of external sensors on the drive of the pneumatic artificial muscle.

[0006] To achieve the above purpose, the present invention provides the following technical solution: A drive and control integrated pneumatic artificial muscle with self-sensing function, characterized in that it includes an upper connector, a main cavity and a lower connector; The upper connector is fixed to the top of the main cavity, and the lower connector is fixed to the bottom of the main cavity. Both the upper connector and the lower connector are connected to the main cavity through serrated triangular patterns to ensure the assembly and airtightness of the pneumatic artificial muscle.

[0007] Compared with the prior art, the present invention has the following advantages and effects: The self-sensing function and drive-control integration of the pneumatic artificial muscle have significant advantages compared with traditional pneumatic muscles. Firstly, the self-sensing function enables the pneumatic artificial muscle to achieve closed-loop control without external sensors, significantly improving the control accuracy and response speed of the system. Secondly, the drive-control integration integrates control, drive, and sensing in the same system, reducing the dependence on external sensors and complex circuits, simplifying the system structure and installation, and reducing the maintenance cost. Finally, by optimizing the control strategy, the working parameters can be adjusted more efficiently, reducing energy waste and improving the overall energy efficiency. Generally speaking, the self-sensing and drive-control integration not only improves the performance of the pneumatic artificial muscle but also enhances its intelligence and automation level, providing a more flexible and reliable solution for complex tasks. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a schematic diagram of the external structure of a drive-control integrated pneumatic artificial muscle with self-sensing function according to an embodiment of the present application; Figure 2 It is a schematic diagram of the external structure of the upper connector according to an embodiment of the present application; Figure 3 It is a schematic diagram of the internal structure of the upper connector according to an embodiment of the present application; Figure 4 It is a schematic diagram of the movable component structure of the air charging and discharging control device according to an embodiment of the present application; Figure 5 It is a schematic diagram of the structure of the main cavity according to an embodiment of the present application; Figure 6 It is a schematic diagram of the structure of the lower connector according to an embodiment of the present application.

[0009] Description of the reference numerals: 1 - Controller and power supply, 2 - Cable harness, 3 - Fastener, 4 - Upper buckle, 5 - Braided network tube and silicone tube, 6 - Lower buckle, 7 - Force sensor, 8 - Air pressure detection device, 9 - Upper joint, 10 - Electromagnet, 11 - Movable ejector rod, 12 - Movable iron core, 13 - Movable ejector rod group, 14 - Inflation cavity channel, 15 - Exhaust cavity channel, 16 - Moving iron core spring, 17 - Piston seal, 18 - Exhaust hole, 19 - Conductive rubber tube, 20 - Lower joint. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0010] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the embodiments of the present application and the drawings.

[0011] As Figure 1As shown in the figure, an integrated driving and controlling pneumatic artificial muscle with self-sensing function (hereinafter referred to as pneumatic muscle) is provided in an embodiment of the present application. It can monitor its own state in real time without external sensors, thereby reducing the dependence on external sensors. The system does not require the installation and maintenance of additional external sensors, simplifies the structure of the overall control system, and thus reduces the overall weight and volume of the system. It has significant advantages especially in weight-sensitive applications (such as robots, bionics, etc.). The pneumatic muscle includes: an upper connector, a main cavity, and a lower connector.

[0012] The upper connector is fixed to the top of the main cavity, and the lower connector is fixed to the bottom of the main cavity. Both the upper connector and the lower connector are connected to the main cavity through serrated triangular patterns to ensure the assembly and airtightness of the pneumatic artificial muscle.

[0013] As Figure 2 shown, the upper connector includes: an upper buckle 4, a pressure detection device 8, and an upper joint 9. The upper buckle 4 is placed on the outermost layer of the upper connector, and the inner layer has the serrated triangular pattern. The upper joint 9 is located below the upper connector, and a pressure detection device 8 capable of wireless transmission is installed near the gas inlet and outlet on it. The pressure detection device 8 can perform pressure detection and transmit the pressure data to the controller through wireless transmission. The purpose of setting the pressure detection device 8 located on the upper joint 9 and facing the cylindrical cavity is to achieve real-time communication with the controller through the wireless communication module inside it, and obtain the internal pressure data of the main cavity in real time on the upper computer interface.

[0014] Furthermore, a controller and a power supply 1 are fixed to the outer surface of the upper connector using a fastener 3, which is used to detect the working state, control the movement of the pneumatic muscle, and supply power to the entire pneumatic muscle to ensure the normal operation of the entire pneumatic muscle.

[0015] Furthermore, the fastener 3 is made of aluminum alloy material.

[0016] As Figure 3 shown, an inflation channel 14, an exhaust channel 15, and an inflation and deflation control device are arranged inside the upper connector. The inflation channel 14 and the exhaust channel 15 are distributed on the left and right symmetric sides of the pneumatic artificial muscle, and the cross-section of the channel is a circular structure.

[0017] As Figure 3 and Figure 4 shown, the inflation and deflation control device is composed of an electromagnet 10, a moving iron core 12, a moving ejector rod group 13, a moving iron core spring 16, and a piston seal 17. The moving iron core 12 is located at the top of the moving ejector rod group 13, the moving ejector rod group 13 stands upright at the center point of the piston seal 17, and the moving iron core spring 16 surrounds the bottom of the moving ejector rod group 13.

[0018] Furthermore, an exhaust hole 18 is provided on the piston seal 17. When the inflation and deflation control device is in a closed state or the electromagnet is not powered, the piston seal 17 moves downward, the inflation cavity 14 is closed, and the exhaust hole 18 is connected with the exhaust cavity 15 to realize the exhaust function.

[0019] like Figure 5 As shown, the main cavity is a cylindrical cavity, the inner layer is a conductive rubber tube 19, and the outer layer is a braided mesh tube and a silicone tube 5. The inner wall of the braided mesh tube and the outer surface of the silicone tube fit tightly, and the outer wall of the conductive rubber tube and the inner wall of the silicone tube fit tightly. The elastic modulus of the conductive rubber and silicone rubber are basically consistent, and the two fit tightly when inflated. That is, the main cavity is respectively conductive rubber tube, silicone rubber tube and braided mesh tube from the inside to the outside; the outer layer is wrapped with a double-helix PET fiber braided mesh tube, the middle layer is a silicone rubber tube, and the inner layer is attached with conductive rubber. The purpose of setting a conductive rubber tube inside the cylindrical cavity is that when the pneumatic muscle is inflated, the cylindrical cavity expands and stretches, causing the cross-sectional area of ​​the rubber tube wall to change, thereby causing the resistance value to change accordingly, realizing the association between the inflation, expansion and contraction displacement of the pneumatic muscle and the resistance, and realizing the self-sensing function of the pneumatic muscle.

[0020] The specifications of the deformable part of the cylindrical cavity are: length 200mm, diameter 30mm. The braided mesh tube and the silicone tube are 200mm long, 30mm outer diameter, and 28mm inner diameter. The conductive rubber tube is 150mm long, 28mm outer diameter, and 26mm inner diameter. The outer wall of the conductive rubber tube fits tightly with the inner wall of the silicone tube and is located in the center of the silicone rubber tube.

[0021] Furthermore, the conductive rubber tube 19 is connected to a wire harness 2, and the wire harness 2 forms a loop with the power supply, which is used to provide voltage to the conductive rubber tube 19, and return the voltage change data during the deformation of the conductive rubber tube to the controller to achieve control of the change in the contraction amount of the pneumatic artificial muscle. During the inflation process, the conductive rubber expands, the diameter increases, and the cross-sectional area decreases, resulting in changes in the current path. The conductive rubber is provided with voltage through the wire, and the voltage data is then transmitted to the controller module to achieve control of the change in the contraction amount of the pneumatic muscle.

[0022] like Figure 6 As shown, the lower end connection member includes: a lower end joint 20, a lower end buckle 6 and an output force detection component. The lower end buckle 6 is ringed outside the lower end joint 20, and the sawtooth triangular pattern is arranged in the interlayer formed by the two.

[0023] Furthermore, the lower end joint 20 and the lower end buckle 6 are both made of alloy materials.

[0024] The output force detection component includes a force sensor 7, which is used to measure the output force of the pneumatic muscle, collect and output the output force data of the pneumatic muscle. The lower end connecting piece of the pneumatic muscle is connected to the upper end bolt of the force sensor. In actual application, the lower end of the force sensor is connected to an external load. When the pneumatic muscle inflates and contracts, the force sensor 7 transmits the output force data to the controller through wireless transmission to achieve closed-loop control of the output force of the pneumatic muscle.

[0025] The working principle of the embodiment of the present application is to place the control system of the pneumatic artificial muscle on the side of the fastener 3, and the host computer sends the displacement, output force, and air pressure signals of the pneumatic artificial muscle to the controller and the power supply 1.

[0026] When the control target is displacement, the host computer sends a signal to the controller. The controller controls the on-off time of the electromagnet to further control the time ratio of the charging and discharging states of the air pressure control device to achieve air pressure control. The host computer obtains the voltage change data during the deformation process of the conductive rubber tube, and after processing, returns it to the controller to achieve closed-loop control of the displacement of the pneumatic muscle.

[0027] When controlling the output force, the host computer sends a signal to the controller. The controller controls the on-off time of the electromagnet to further control the time ratio of the charging and discharging states of the air pressure control device to achieve air pressure control. The force sensor 7 returns the output force signal to the host computer, and after processing, it is transmitted to the controller to achieve closed-loop control of the output force of the pneumatic muscle.

[0028] The host computer sends a signal to the controller. When controlling the air pressure, the controller controls the on-off time of the electromagnet 10 to further control the time ratio of the charging and discharging states of the air pressure control device to achieve air pressure control. The air pressure sensor returns the output force signal to the host computer, and after processing, it is transmitted to the controller to achieve closed-loop control of the air pressure of the pneumatic muscle.

[0029] In summary, the present invention realizes the self-sensing function without an external sensor, and achieves the advantages of cascade multi-loop closed-loop control and integrated drive control structure. It can enable the system applying this pneumatic muscle to maintain excellent performance in a changing working environment, and has great advantages in the drive control of bionic flexible robots and pneumatic manipulators, and has a wide range of applications in many fields such as bionic robots and rehabilitation medicine.

Claims

1. A pneumatic artificial muscle with a drive and control integrated structure having a self-sensing function, characterized in that, It includes an upper end connector, a main cavity, and a lower end connector; The upper end connector is fixed to the top of the main cavity, and the lower end connector is fixed to the bottom of the main cavity. Both the upper end connector and the lower end connector are connected to the main cavity through serrated triangular patterns to ensure the assembly and airtightness of the pneumatic artificial muscle.

2. The integrated driving and controlling pneumatic artificial muscle with self-sensing function according to claim 1, characterized in that, The upper end connector includes: an upper end buckle, a pressure detection device, and an upper end joint; The upper end buckle is placed on the outermost layer of the upper end connector, and the inner layer has the serrated triangular pattern; The upper end joint is located below the upper end connector, and a pressure detection device is installed at the gas inlet and outlet positions thereon, and the pressure detection device faces the main cavity.

3. The integrated driving and controlling pneumatic artificial muscle with self-sensing function according to claim 2, characterized in that, A controller and a power source are fixed to the outer surface of the upper end connector using fasteners, which are used to detect the working state, control the movement of the pneumatic artificial muscle, and supply power to the entire pneumatic artificial muscle.

4. A drive and control integrated pneumatic artificial muscle with self-sensing function according to any one of claims 1-3, characterized in that, An inflation channel, an exhaust channel, and an inflation and deflation control device are provided inside the upper end connector; The inflation channel and the exhaust channel are distributed on the left and right symmetric sides of the pneumatic artificial muscle; The inflation and deflation control device includes a movable iron core, a movable ejector rod group, a moving iron core spring, and a piston seal; The movable iron core is located at the top of the movable ejector rod group. The movable ejector rod group stands upright at the center point of the piston seal, and the moving iron core spring surrounds the bottom of the movable ejector rod group.

5. A drive and control integrated pneumatic artificial muscle with self-sensing function according to claim 4, characterized in that, An exhaust hole is provided on the piston seal. When the inflation and deflation control device is in the closed state or the electromagnet is not powered, the piston seal moves downward, the inflation channel is closed, and the exhaust hole communicates with the exhaust channel to achieve the exhaust function.

6. The integrated driving and controlling pneumatic artificial muscle with self-sensing function according to claim 1, characterized in that, The lower end connector includes: a lower end joint, a lower end buckle, and an output force detection component; The lower end buckle rings outside the lower end joint, and the serrated triangular pattern is provided in the sandwich formed by the two; The output force detection component is installed at the bottom of the lower end connector, and the two are connected by bolts.

7. The integrated driving and controlling pneumatic artificial muscle with self-sensing function according to claim 6, characterized in that, The lower end of the output force detection component is connected to an external load. When the pneumatic artificial muscle inflates and contracts, the output force detection component transmits the output force data to the controller to achieve the closed-loop control of the output force of the pneumatic muscle.

8. The integrated driving and controlling pneumatic artificial muscle with self-sensing function according to claim 1, characterized in that, The main cavity is a cylindrical cavity. The inner layer is a conductive rubber tube, and the outer layer is a braided network tube and a silicone tube; the inner wall of the braided network tube and the outer surface of the silicone tube are closely attached, and the outer wall of the conductive rubber tube and the inner wall of the silicone tube are closely attached.

9. The integrated pneumatic artificial muscle with self-sensing function according to claim 8, characterized in that, The length of the braided network tube and the silicone tube is 200 mm, the outer diameter is 30 mm, and the inner diameter is 28 mm; the length of the conductive rubber tube is 150 mm, the outer diameter is 28 mm, and the inner diameter is 26 mm.

10. The integrated driving and controlling pneumatic artificial muscle with self-sensing function according to claim 8 or 9, characterized in that, The conductive rubber tube is connected to a wire bundle, and the wire bundle forms a circuit with the power source, which is used to provide voltage to the conductive rubber tube and transmit the voltage data to the controller to achieve the control of the change in the contraction amount of the pneumatic artificial muscle.

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