阅读说明：本技术 基于壅塞原理的软体机器人气动系统 (Soft robot pneumatic system based on congestion principle ) 是由 章军 刘禹 庞玮 王震宇 陈彦秋 吕兵 于 2021-06-08 设计创作，主要内容包括：本发明涉及一种基于壅塞原理的软体机器人气动系统,包括外部先导式减压阀,外部先导式减压阀的进气端连接气源；第一进气部分,第一进气部分连接软体机器人和所述外部先导式减压阀的出气端；其用于控制以大流量向所述软体机器人内进气,直至所述软体机器人内腔压力趋近目标压力；第二进气部分,所述第二进气部分连接软体机器人和所述外部先导式减压阀的出气端；用于当所述软体机器人内腔压力达到所述目标压力时,基于壅塞原理控制以微流量向所述软体机器人内进气。本发明气动系统,第一种运行模式下能够驱动软体机器人快速响应、反应灵敏；第二种运行模式下能够可靠的较长时间维持完全壅塞流状态,该模式下能够较高精度的控制驱动软体机器人动作。(The invention relates to a soft robot pneumatic system based on a choking principle, which comprises an external pilot type pressure reducing valve, wherein the air inlet end of the external pilot type pressure reducing valve is connected with an air source; the first air inlet part is connected with the soft robot and the air outlet end of the external pilot type pressure reducing valve; the device is used for controlling air to be fed into the soft robot in a large flow until the pressure of an inner cavity of the soft robot approaches a target pressure; the second air inlet part is connected with the soft robot and the air outlet end of the external pilot type pressure reducing valve; and the device is used for controlling the air to be fed into the soft robot in micro flow based on the congestion principle when the pressure in the inner cavity of the soft robot reaches the target pressure. The pneumatic system can drive the soft robot to quickly respond and respond sensitively in the first operation mode; in the second operation mode, the completely choked flow state can be reliably maintained for a long time, and the operation of the soft robot can be controlled and driven with higher precision in the second operation mode.)

1. A soft robot pneumatic system based on a choking principle is characterized in that: comprises the steps of (a) preparing a mixture of a plurality of raw materials,

the air inlet end of the external pilot type pressure reducing valve is connected with an air source;

the first air inlet part is connected with the soft robot and the air outlet end of the external pilot type pressure reducing valve; the system is used for controlling air to be fed into the soft robot at a first flow rate until the pressure of an inner cavity of the soft robot approaches a target pressure;

the second air inlet part is connected with the soft robot and the air outlet end of the external pilot type pressure reducing valve; the device is used for controlling air to enter the soft robot at a second flow rate based on the choking principle when the pressure of the inner cavity of the soft robot approaches the target pressure; the second flow rate is less than the first flow rate;

and the control gas circuit of the external pilot-operated pressure relief valve is connected with the inlet gas circuit of the soft robot.

2. The soft robotic pneumatic system according to claim 1, wherein the pneumatic system further comprises: the first air inlet part comprises an air inlet adjustable throttle valve, a low-frequency high-speed switch valve and a first air inlet pipeline, and the first air inlet pipeline is connected with the soft robot and the air outlet end of the external pilot type pressure reducing valve; the air inlet adjustable throttle valve is arranged on the first air inlet pipeline and is used for controlling air inlet at the first flow rate; the low-frequency high-speed switch valve is arranged on the first air inlet pipeline and is used for controlling the on-off of air inlet into the soft robot.

3. The soft robotic pneumatic system according to claim 1, wherein the pneumatic system further comprises: the second air inlet part comprises a small-hole throttle valve, a high-frequency high-speed switch valve and a second air inlet pipeline, and the second air inlet pipeline is connected with the soft robot and the air outlet end of the external pilot type pressure reducing valve; the small-hole throttle valve is arranged on the second air inlet pipeline and is used for controlling air inlet at the second flow rate; the high-frequency high-speed switch valve is arranged on the second air inlet pipeline and is used for controlling the on-off of air inlet into the soft robot; the high-frequency high-speed switch valve is arranged on the air outlet side of the small-hole throttle valve.

4. The soft robotic pneumatic system according to claim 2, wherein the pneumatic system further comprises: the second air inlet part comprises a small-hole throttle valve, a high-frequency high-speed switch valve and a second air inlet pipeline, and the second air inlet pipeline is connected with the soft robot and the air outlet end of the air inlet adjustable throttle valve; the small-hole throttle valve is arranged on the second air inlet pipeline and is used for controlling air inlet at the second flow rate; the high-frequency high-speed switch valve is arranged on the second air inlet pipeline and is used for controlling the on-off of air inlet into the soft robot; the high-frequency high-speed switch valve is arranged on the air outlet side of the small-hole throttle valve.

5. The soft robotic pneumatic system according to claim 1, wherein the pneumatic system further comprises: the system also comprises a pressure feedback part, wherein the pressure feedback part comprises a rear pressure sensor capable of dynamically detecting the pressure of the inner cavity of the soft robot.

6. The soft robotic pneumatic system according to claim 5, wherein the pneumatic system further comprises: the pressure feedback section also includes a pre-pressure sensor capable of dynamically measuring orifice throttle inlet pressure.

7. The soft robotic pneumatic system according to claim 1, wherein the pneumatic system further comprises: the system also comprises a safety gas path part, wherein the safety gas path part comprises a safety valve, the safety valve is arranged at the end of the gas inlet pipe of the soft robot, and the set pressure of the safety valve is less than or equal to the rated pressure of the inner cavity of the soft robot.

8. The soft robotic pneumatic system according to claim 1, wherein the pneumatic system further comprises: the system also comprises a first air outlet part, wherein the first air outlet part comprises a first air outlet pipeline connected with the soft robot, an air outlet adjustable throttle valve and an air outlet switch valve which are arranged on the first air outlet pipeline; or the second air outlet part comprises a second air outlet pipeline connected with the soft robot, a vacuum path switch valve arranged on the second air outlet pipeline and a vacuum pump.

9. The soft robotic pneumatic system according to claim 1, wherein the pneumatic system further comprises: the system is provided with a multi-way combination valve, and the external pilot type pressure reducing valve is assembled and fixed with the multi-way combination valve; a first interface (i1) of a valve body of the multi-way combination valve is connected with an air outlet of the external pilot type pressure reducing valve, a second interface (o1) of the multi-way combination valve is connected with a control air path inlet of the external pilot type pressure reducing valve, a third interface (o2) of the multi-way combination valve is connected with an inlet of a high-frequency high-speed switch valve, a fourth interface (i2) of the multi-way combination valve is connected with an outlet of the high-frequency high-speed switch valve, a fifth interface (o3) of the multi-way combination valve is connected with an inlet of an air inlet adjustable throttle valve, and an outlet of the air inlet adjustable throttle valve is connected with an inlet of a low-frequency high-speed switch valve; the sixth interface (o4) is connected with a rear pressure sensor; the valve body of the multi-way combination valve is also provided with three seventh interfaces (io), and the three seventh interfaces (io) are respectively connected with the outlet of the low-frequency high-speed switch valve, the inlet of the safety valve and the soft robot; the three seventh port, the fourth port (i2), the second port (o1), and the sixth port (o4) are communicated with each other within the valve body of the multiple combination valve.

10. The soft robotic pneumatic system according to claim 1, wherein the pneumatic system further comprises: the system is provided with a multi-way combination valve, wherein a first interface (i1) of a valve body of the multi-way combination valve is connected with an outlet of the external pilot-operated type pressure reducing valve, a second interface (o1) of the multi-way combination valve is connected with a control gas circuit inlet of the external pilot-operated type pressure reducing valve, a third interface (o2) of the multi-way combination valve is connected with an inlet of a high-frequency high-speed switch valve, a fourth interface (i2) of the multi-way combination valve is connected with an outlet of the high-frequency high-speed switch valve, a fifth interface (o3) of the multi-way combination valve is connected with an inlet of a low-frequency high-speed switch valve, and a sixth interface (o4) of the multi-way combination valve is connected with a rear pressure sensor; the valve body of the multi-way combination valve is also provided with three seventh interfaces (io), and the three seventh interfaces are respectively connected with the outlet of the low-frequency high-speed switch valve, the inlet of the safety valve and the soft robot; the three seventh port, the fourth port (i2), the second port (o1), and the sixth port (o4) are communicated with each other within the valve body of the multiple combination valve.

Technical Field

The invention relates to the technical field of pneumatic drive (pneumatic for short), in particular to a pneumatic system of a soft robot based on a choking principle, which is mainly applied to a pneumatic soft robot, and is particularly applied to pneumatic soft fingers or pneumatic artificial muscles.

Background

The soft robot is designed to simulate various soft organisms in the nature, such as earthworms, octopus, jellyfish and the like, is made of soft materials (such as rubber), can adapt to various unstructured environments, and is safer to interact with human beings. The soft robot is driven by a pneumatic system to realize action, and the difference between the soft robot and the cylinder driving is that the soft robot does not have two sealing frictions of a cylinder piston and a piston rod, so that the soft robot does not generate a creeping phenomenon during micro-flow driving.

For fast performance, the existing throttling for cylinder driven pneumatic systems is based on the principle of incomplete choked flow, with the disadvantages including: the high-speed air throttle valve is difficult to control the cylinder driving pressure with high precision through flow parameters.

In order to overcome the drawbacks of pneumatic systems based on the principle of incomplete choked flow, the related documents disclose pneumatic systems for cylinder driving based on the principle of complete choked flow, according to the aerodynamic principle of complete choked flow: the small-hole throttling valve (the non-adjustable throttling valve with the small hole) is adopted, the opening of the small-hole throttling valve is small and fixed, the small-hole throttling valve is equivalent to the phenomenon of slow air leakage of the small hole, when the ratio of the outlet pressure to the inlet pressure of the small-hole throttling valve is less than 0.528, the small-hole throttling valve enters a completely choked flow state, the gas speed at the small hole of the throttling valve is sound speed, the gas mass flow at the outlet of the small-hole throttling valve is constant, the step property of the mass flow of the small-hole throttling valve in the opening and closing process of the switching valve is good, and the modeling, the numerical calculation and the pressure control of a pneumatic actuator can be conveniently carried out through mass flow parameters. However, the volume flow under the completely choked flow is very small, the action of the pneumatic actuator is too slow, and the completely choked flow state with the ratio of the outlet pressure to the inlet pressure being less than 0.528 is related to the aperture of the orifice throttle valve and the inlet pressure, and the aperture is large, the inlet pressure is large, the flow is large, and the duration is short after the condition is met.

On the other hand, although the soft robot driven by the pneumatic system based on the choked flow principle can facilitate modeling, numerical calculation and pressure control of the pneumatic actuator through mass flow parameters, the response speed of the soft robot driven by the pneumatic system based on the choked flow principle is very slow.

Disclosure of Invention

Therefore, the technical problem to be solved by the invention is to overcome the problems that the pneumatic system for driving the soft robot in the prior art is difficult to maintain a completely choked flow state and causes slow response speed of the soft robot, and provide the soft robot pneumatic system based on the choking principle, wherein the soft robot can be driven to quickly respond and respond sensitively in a first operation mode; in the second operation mode, the completely choked flow state can be reliably maintained for a long time, and the operation of the soft robot can be controlled and driven with higher precision in the second operation mode.

In order to solve the above technical problems, the present invention provides a soft body robot pneumatic system based on the congestion principle, comprising,

the air inlet end of the external pilot type pressure reducing valve is connected with an air source;

the first air inlet part is connected with the soft robot and the air outlet end of the external pilot type pressure reducing valve; the system is used for controlling air to be fed into the soft robot at a first flow rate until the pressure of an inner cavity of the soft robot approaches a target pressure;

the second air inlet part is connected with the soft robot and the air outlet end of the external pilot type pressure reducing valve; the device is used for controlling air to enter the soft robot at a second flow rate based on the choking principle when the pressure of the inner cavity of the soft robot approaches the target pressure; the second flow rate is less than the first flow rate;

and the control gas circuit of the external pilot-operated pressure relief valve is connected with the inlet gas circuit of the soft robot.

In one embodiment of the invention, the first air inlet part comprises an air inlet adjustable throttle valve, a low-frequency high-speed switch valve and a first air inlet pipeline, and the first air inlet pipeline is connected with the soft robot and the air outlet end of the external pilot type pressure reducing valve; the air inlet adjustable throttle valve is arranged on the first air inlet pipeline and is used for controlling air inlet at the first flow rate; the low-frequency high-speed switch valve is arranged on the first air inlet pipeline and is used for controlling the on-off of air inlet into the soft robot.

In one embodiment of the invention, the second air inlet part comprises a small-hole throttle valve, a high-frequency high-speed switch valve and a second air inlet pipeline, and the second air inlet pipeline is connected with the soft robot and the air outlet end of the external pilot type pressure reducing valve; the small-hole throttle valve is arranged on the second air inlet pipeline and is used for controlling air inlet at the second flow rate; the high-frequency high-speed switch valve is arranged on the second air inlet pipeline and is used for controlling the on-off of air inlet into the soft robot; the high-frequency high-speed switch valve is arranged on the air outlet side of the small-hole throttle valve.

In one embodiment of the invention, the second air inlet part comprises a small-hole throttle valve, a high-frequency high-speed switch valve and a second air inlet pipeline, and the second air inlet pipeline is connected with the soft robot and the air outlet end of the air inlet adjustable throttle valve; the small-hole throttle valve is arranged on the second air inlet pipeline and is used for controlling air inlet at the second flow rate; the high-frequency high-speed switch valve is arranged on the second air inlet pipeline and is used for controlling the on-off of air inlet into the soft robot; the high-frequency high-speed switch valve is arranged on the air outlet side of the small-hole throttle valve.

In one embodiment of the invention, the system further comprises a pressure feedback part, wherein the pressure feedback part comprises a rear pressure sensor capable of dynamically detecting the pressure of the inner cavity of the soft robot.

In one embodiment of the invention, the pressure feedback section further comprises a pre-pressure sensor capable of dynamically measuring orifice throttle inlet pressure.

In one embodiment of the invention, the system further comprises a safety gas path part, wherein the safety gas path part comprises a safety valve, the safety valve is arranged at the end of the gas inlet pipe of the soft robot, and the set pressure of the safety valve is less than or equal to the rated pressure of the inner cavity of the soft robot.

In an embodiment of the invention, the system further comprises a first air outlet part, wherein the first air outlet part comprises a first air outlet pipeline connected with the soft robot, an air outlet adjustable throttle valve and an air outlet switch valve which are arranged on the first air outlet pipeline; or the second air outlet part comprises a second air outlet pipeline connected with the soft robot, a vacuum path switch valve arranged on the second air outlet pipeline and a vacuum pump.

In one embodiment of the invention, the system is provided with a multi-way combination valve, and the external pilot-operated reducing valve is assembled and fixed with the multi-way combination valve; a first interface (i1) of a valve body of the multi-way combination valve is connected with an air outlet of the external pilot type pressure reducing valve, a second interface (o1) of the multi-way combination valve is connected with a control air path inlet of the external pilot type pressure reducing valve, a third interface (o2) of the multi-way combination valve is connected with an inlet of a high-frequency high-speed switch valve, a fourth interface (i2) of the multi-way combination valve is connected with an outlet of the high-frequency high-speed switch valve, a fifth interface (o3) of the multi-way combination valve is connected with an inlet of an air inlet adjustable throttle valve, and an outlet of; the sixth interface (o4) is connected with a rear pressure sensor; the valve body of the multi-way combination valve is also provided with three seventh interfaces (io), and the three seventh interfaces (io) are respectively connected with the outlet of the low-frequency high-speed switch valve, the inlet of the safety valve and the soft robot; the three seventh port, the fourth port (i2), the second port (o1), and the sixth port (o4) are communicated with each other within the valve body of the multiple combination valve.

In one embodiment of the invention, the system is provided with a multi-way combination valve, wherein a first interface (i1) of a valve body of the multi-way combination valve is connected with an outlet of the external pilot-operated type pressure reducing valve, a second interface (o1) of the multi-way combination valve is connected with a control gas circuit inlet of the external pilot-operated type pressure reducing valve, a third interface (o2) of the multi-way combination valve is connected with an inlet of a high-frequency high-speed switch valve, a fourth interface (i2) of the multi-way combination valve is connected with an outlet of the high-frequency high-speed switch valve, a fifth interface (o3) of the multi-way combination valve is connected with an inlet of a low-frequency high-speed switch valve, and a sixth interface (o4) of the multi-way combination valve is connected with a rear pressure sensor; the valve body of the multi-way combination valve is also provided with three seventh interfaces (io), and the three seventh interfaces are respectively connected with the outlet of the low-frequency high-speed switch valve, the inlet of the safety valve and the soft robot; the three seventh port, the fourth port (i2), the second port (o1), and the sixth port (o4) are communicated with each other within the valve body of the multiple combination valve.

Compared with the prior art, the technical scheme of the invention has the following advantages:

according to the soft robot pneumatic system based on the choking principle, compressed air is firstly subjected to pressure reduction treatment by an external pilot type pressure reducing valve, the compressed air with stable pressure is output from an air outlet end of the compressed air, the compressed air treated by the external pilot type pressure reducing valve is divided into two paths, and one path of the compressed air is used for introducing air from a first air inlet part of a large-flow air path to an inner cavity of the soft robot, so that the quick response action of the soft robot is driven; one path of the air is fed into the inner cavity of the soft robot by the second progress part of the micro-flow air path, and the inlet and outlet pressure of the micro-flow air path is controlled to meet the completely choked flow state, so that the pressure of the inner cavity of the soft robot is accurately controlled to the target pressure, and the fine action of the soft robot is driven; meanwhile, the control gas circuit of the external pilot-operated pressure reducing valve is connected with the inlet gas circuit of the soft robot, so that the second gas inlet part with the micro-flow gas circuit can reliably maintain the completely choked flow state for a long time. The pneumatic system can compatibly realize quick response and sensitive response of the soft driving robot in the first operation mode; in the second operation mode, the completely choked flow state is reliably maintained for a long time, and the fine motion of the soft robot can be controlled and driven with higher precision in the second operation mode.

Drawings

In order that the present disclosure may be more readily and clearly understood, the following detailed description of the present disclosure is provided in connection with specific embodiments thereof and the accompanying drawings, in which,

FIG. 1 is a schematic diagram of a soft-body robot pneumatic system based on the congestion principle according to a first embodiment of the present invention;

FIG. 2 is a front view of a multiple combination valve used in the first embodiment; a

FIG. 3 is a sectional view of the multi-way combination valve A-A of FIG. 2;

FIG. 4 is a cross-sectional view of the multiple combination valve of FIG. 3 taken in the direction B-B;

FIG. 5 is a schematic diagram of a soft-body robot pneumatic system based on the congestion principle according to a second embodiment of the present invention;

FIG. 6 is a front view of a multiple combination valve used in the second embodiment;

FIG. 7 is a cross-sectional view of the multiplex combination valve C-C of FIG. 6;

fig. 8 is a sectional view of the multiple combination valve D-D shown in fig. 7.

The specification reference numbers indicate:

1-a soft robot; 2-external piloted pressure relief valve; 41-an air inlet adjustable throttle valve, 42-a low-frequency high-speed switch valve and 43-a first air inlet pipeline; 61-a small hole throttle valve, 62-a high-frequency high-speed switch valve, 63-a second air inlet pipeline; 81-a first gas outlet pipeline, 82-a gas outlet adjustable throttle valve and 83-a gas outlet switch valve; 91-a second air outlet pipeline, 92-a vacuum path switching valve and 93-a vacuum pump; 10-safety valve; 11-front pressure sensor, 12-back pressure sensor.

In the multichannel combination valve: 101. a valve hole wafer; 102. a large seal ring; 103. screwing a cover through the radial hole; 104. the plug can be disassembled; 105. a small seal ring; 106. a large valve body; 107. a small valve body; 108. the plug cannot be disassembled; 109. a cone head throttling valve core; 110. locking the thin nut; 111. a diamond-shaped seat; 112. and (4) a fine sealing ring.

Detailed Description

The present invention is further described below in conjunction with the following figures and specific examples so that those skilled in the art may better understand the present invention and practice it, but the examples are not intended to limit the present invention.

Example one

Referring to fig. 1, the invention discloses a soft robot pneumatic system based on a choking principle, which comprises an external pilot type pressure reducing valve 2, wherein an air inlet end of the external pilot type pressure reducing valve 2 is connected with an air source; the first air inlet part is connected with the air outlet ends of the soft robot 1 and the external pilot type pressure reducing valve 2; the system is used for controlling air to be fed into the soft robot 1 at a first flow rate until the pressure of an inner cavity of the soft robot 1 approaches a target pressure; the second air inlet part is connected with the air outlet ends of the soft robot 1 and the external pilot type pressure reducing valve 2; the device is used for controlling air to enter the soft robot 1 at a second flow rate based on the choking principle when the pressure in the inner cavity of the soft robot 1 reaches the target pressure; the second flow rate is much less than the first flow rate; and the control gas circuit of the external pilot type pressure reducing valve 2 is connected with the inlet gas circuit of the soft robot 1.

The soft robot pneumatic system based on the congestion principle comprises an external pilot type pressure reducing valve 2, wherein the air inlet end of the external pilot type pressure reducing valve 2 is connected with an air source, compressed air of the air source is subjected to pressure reduction treatment by the external pilot type pressure reducing valve 2, and the air outlet end of the air source outputs compressed air with stable pressure; the compressed air processed by the external pilot type reducing valve 2 is divided into two paths, and one path of the compressed air is supplied to the inner cavity of the soft robot 1 through a first air inlet part; one route is used for introducing air into the inner cavity of the soft robot 1 through the second air inlet part. The first air inlet part is used for controlling air to be fed into the soft robot 1 at a first flow rate until the pressure of the inner cavity of the soft robot 1 approaches a target pressure; the first flow is set to be large, and in an initial state or when the pressure of the inner cavity of the soft robot does not reach the target pressure, the first air inlet part is used for introducing air into the inner cavity of the soft robot in a large flow mode, so that the soft robot 1 is driven to respond quickly when the soft robot operates in the large flow mode.

When the pressure of the inner cavity of the soft robot 1 approaches the target pressure, the first air inlet part is disconnected, and the second air inlet part is used for introducing air into the soft robot 1 at a second flow rate until the pressure of the inner cavity of the soft robot 1 reaches the target pressure. The second flow is set to be micro-flow, and on the basis that the pressure of the inlet and the outlet of the small-hole throttle valve 61 of the second air inlet part meets the choked flow state, the pressure of the inner cavity of the soft robot is accurately controlled to the target pressure by controlling the two air inlet parts to be opened and closed quickly, so that the soft robot is driven to perform fine actions, such as accurately controlling the posture and the contact state of the soft robot 1.

The control gas circuit of the external pilot type pressure reducing valve 2 is connected with the inlet gas circuit of the soft robot 1, so that the second gas inlet part with a micro-flow gas circuit can reliably maintain a completely choked flow state for a long time. Specifically, referring to fig. 1, the first air intake part includes an air intake adjustable throttle valve 41, a low-frequency high-speed switching valve 42 and a first air intake pipeline 43, and the air intake adjustable throttle valve 41 has an adjustable flow rate; the switching frequency of the low-frequency high-speed switching valve 42 is less than 100 Hz; the first air inlet pipeline 43 is connected with the air outlet ends of the soft robot 1 and the external pilot type pressure reducing valve 2; the intake adjustable throttle valve 41 is provided in the first intake line 43 for controlling intake air at the first flow rate; the low-frequency high-speed switch valve 42 is disposed on the first air inlet pipeline 43 and is used for controlling the on-off of air inlet into the soft robot 1. The second air inlet part comprises a small hole throttle valve 61, a high-frequency high-speed switch valve 62 and a second air inlet pipeline 63, and the aperture of the small hole throttle valve is 0.05-2 mm; the switching frequency of the high-frequency high-speed switching valve 62 is 100Hz or more than 100 Hz. The second air inlet pipeline 63 is connected with the air outlet ends of the soft robot 1 and the external pilot type pressure reducing valve 2; the orifice throttle valve 61 is provided in the second intake line 63 for controlling intake air at the second flow rate; the high-frequency high-speed switch valve 62 is disposed in the second air inlet pipeline 63 and is used for controlling on-off of air inlet into the soft robot 1.

In order to ensure the safety of the soft robot 1, the system further comprises a safety gas path part, wherein the safety gas path part comprises a safety valve 10, the safety valve 10 is arranged at the end of a gas inlet pipe of the soft robot 1, the set pressure of the safety valve is less than or equal to the rated pressure of the inner cavity of the soft robot 1, and the safety of the soft robot 1 is ensured.

In an initial state or when the pressure in the inner cavity of the soft robot 1 is lower than 90-99% of target pressure, the first air inlet part is used for introducing air into the inner cavity of the soft robot 1 in a large flow, and when the pressure in the inner cavity of the soft robot 1 reaches 90-99% of the target pressure, the first air inlet part is disconnected, and the second air inlet part is used for introducing air into the inner cavity of the soft robot 1 in a micro-flow manner; when the pressure in the inner cavity of the soft robot 1 reaches the target pressure, the second air inlet part is disconnected.

In order to accurately control the switching of the two modes, the pneumatic system further comprises a pressure feedback part, the pressure feedback part comprises a post-pressure sensor 12 which can dynamically detect the pressure in the inner cavity of the soft robot 1 and the outlet pressure of the external pilot type pressure reducing valve 2, and the operation mode of the pneumatic system is switched according to the pressure in the inner cavity of the soft robot 1 fed back by the post-pressure sensor 12. According to the pressure of the pilot feedback port of the external pilot type reducing valve 2 (namely the pressure of the inner cavity of the soft robot 1) fed back by the rear pressure sensor 12, the second air inlet part can be controlled more accurately to maintain a completely choked flow state for a long time.

The control gas circuit of the external pilot type pressure reducing valve 2 is connected with the inlet gas circuit of the soft robot 1, the pressure of compressed air is lower than the rated pressure of the inner cavity of the soft robot 1, the safety requirement of the soft robot 1 is met, and the ratio of the outlet pressure to the inlet pressure of the small-hole throttle valve is less than 0.528, so that the choking condition is met. For example, the system pressure of a constant pressure air source consisting of an air compressor and an air tank is 0.7MPa, the set pressure of the safety valve 10 is 0.33MPa, the maximum bearing pressure of the inner cavity of the soft robot 1 is 0.35MPa, and the maximum working pressure is 0.32 MPa; the outlet pressure of the external pilot type pressure reducing valve 1 is required to be greater than 0.61 (namely 0.32/0.528, and the choking condition of the orifice throttle valve can be met under the condition that the pressure of the inlet gas circuit of the soft robot 1 reaches the maximum working pressure of 0.32 MPa); when the pressure of the inlet gas circuit of the soft robot 1 is less than 0.32MPa, the external pilot type pressure reducing valve 2 is opened; when the pressure of the inlet gas path of the soft robot 1 is equal to 0.32MPa, the external pilot type pressure reducing valve 2 controls the gas path to close, thereby ensuring that the small-hole throttle valve 61 always works in a completely choked flow state. On the premise that the pressure of the inlet gas circuit of the soft robot 1 is less than 0.32MPa, according to the pressure of the inner cavity of the soft robot 1 fed back by the rear pressure sensor 12, when the pressure of the inner cavity of the soft robot 1 reaches 90-99% of the target pressure (any value less than 0.32 MPa), the control is switched from the large flow mode to the micro flow mode, and according to the pressure of the pilot feedback port of the external pilot type pressure reducing valve 2 fed back by the rear pressure sensor 12 (namely the pressure of the inner cavity of the soft robot 1), the on-off of the high-frequency high-speed switch valve 42 is controlled by adopting a PWM mode to achieve the accurate target pressure.

Referring to fig. 1, the pneumatic system further includes a first air outlet portion, and the first air outlet portion includes a first air outlet pipeline 81 connected to the soft robot 1, an air outlet adjustable throttle valve 82 and an air outlet switch valve 83 both disposed on the first air outlet pipeline 81. After the duration time of the pose or contact state of the soft robot 1 is over, the 3DT is powered on, the air outlet switch valve 83 is powered on, the gas in the inner cavity of the soft robot 1 is directly discharged, or the gas is discharged through the air outlet adjustable throttle valve 82, the gas pressure in the inner cavity of the soft robot 1 is communicated with atmosphere (the gas pressure in the inner cavity is zero), the 3DT is powered off, and the air outlet switch valve 83 is powered off; when the initial state of the soft robot 1 needs to be changed, the gas pressure in the inner cavity of the soft robot 1 can be larger than zero (early power-off 3 DT).

The high-frequency high-speed switch valve 62 is arranged on the air outlet side of the orifice throttle valve 61, so that the inlet pressure of the orifice throttle valve 61 is not influenced at the opening and closing moment of the high-frequency high-speed switch valve 62, and the mass flow of the orifice throttle valve 61 is not influenced by the continuously increased change of the outlet pressure (namely the inner cavity pressure of the soft robot 1) of the orifice throttle valve 61 at the opening and closing moment of the high-frequency high-speed switch valve 62 under the condition that the ratio of the outlet pressure to the inlet pressure of the orifice throttle valve 61 is less than 0.5282. The mass flow rate at the moment of opening and closing the orifice throttle valve 61 in the micro flow rate mode has good step property, and the pulse control effect of the mass flow rate is achieved by opening and closing the high-frequency high-speed opening and closing valve 62.

Referring to fig. 1, the pneumatic system further includes a second air outlet portion, and the second air outlet portion includes a second air outlet pipeline 91 connected to the soft robot 1, a vacuum path switching valve 92 disposed on the second air outlet pipeline 91, and a vacuum pump 93. When the soft robot (such as a pneumatic soft finger) needs to be in an initial state of bending outwards and reversely or when the pneumatic soft finger grips outwards and reversely (grips outwards and outwards in an opening manner opposite to an inwards pinching manner), a negative pressure state is required, wherein the negative pressure state is realized by electrifying the 4DT and switching on the vacuum pump 93 or the vacuum tank by the vacuum circuit switch valve 92.

The external pilot type pressure reducing valve 2 control target includes: firstly, the driving gas pressure of the soft robot 1 is lower than the rated pressure of the inner cavity of the soft robot 1, so that the safety requirement of the soft robot 1 is met; secondly, the ratio of the outlet pressure to the inlet pressure of the orifice throttle valve is ensured to be less than 0.528, thereby satisfying the choking condition. The method comprises the following steps: compressed air of a constant-pressure air source is output through an external pilot type pressure reducing valve 2 and divided into two paths, one path enters an inner cavity of the soft robot 1 through a first air inlet pipeline, the other path enters the inner cavity of the soft robot through a second air inlet pipeline, an air inlet adjustable throttle valve 41 and a low-frequency high-speed switch valve 42 on the first air inlet pipeline control air inlet with large flow, a small-hole throttle valve 61 and a high-frequency high-speed switch valve 62 on the second air inlet pipeline control air inlet with micro flow in a choked state, then outlets of the first air inlet pipeline and the second air inlet pipeline are combined to an air inlet pipe of the soft robot 1, the compressed air enters the inner cavity of the soft robot 1 to be driven, and a feedback control air path of the external pilot type pressure reducing valve 2 is communicated with the air inlet pipe of the soft robot 2 (shown by dotted lines in figure 1); the rear pressure sensor 12, the inlet of the safety valve 10, the inlet of the air outlet switch valve 83 and the inlet of the vacuum path switch valve 92 are communicated with the air inlet pipe of the soft robot 1; the outlet of the air outlet switch valve 83 is directly communicated with the atmosphere, or is connected with the inlet of the air outlet adjustable throttle valve 82, and the outlet of the air outlet adjustable throttle valve 82 is communicated with the atmosphere; the multi-path pneumatic system of the soft robot 1 is provided with or without a vacuum air path consisting of a vacuum air path switch valve 11 and a vacuum pump 12 or a vacuum tank, and the outlet of the vacuum air path switch valve 11 is connected with the vacuum pump 12 or the vacuum tank.

The air source connected with the air inlet end of the external pilot type pressure reducing valve is a constant pressure air source or a non-constant pressure air source, when ultrahigh precision is required, the constant pressure air source consists of an air compressor and an air tank, and a chemical modeling and control strategy is simple when the constant pressure air source is adopted; when high accuracy is required, dynamic mathematical modeling and control strategies are complex when a non-constant pressure air source is adopted, the inlet end of the orifice throttling valve is connected with a preposed pressure sensor 11, and the inlet pressure of the orifice throttling valve is dynamically measured.

The application of the pneumatic system is matched with a multi-way combination valve, the multi-way combination valve comprises an external pilot type pressure reducing valve 2 (in a double-dotted line frame in figure 1), a small-hole throttle valve 61 and a connecting pipeline, and as shown in figures 2, 3 and 4, the external pilot type pressure reducing valve 2 (not shown in the figures) and the multi-way combination valve are assembled together by a screw; all gas circuits have been concentrated to big valve body 106 on the multi-channel combination valve, and the gas circuit is connected: the first interface i1 of the large valve body 106 is connected with the outlet of the external pilot type pressure reducing valve 2, the second interface o1 is connected with the inlet of the control gas path of the external pilot type pressure reducing valve 2, and the two interfaces are sealed by the small sealing ring 105; the third port o2 is connected with the inlet of the high-frequency high-speed switch valve 62 through a pipe, and the fourth port i2 is connected with the outlet of the high-frequency high-speed switch valve 62 through a pipe; the fifth interface o3 pipe is connected with the inlet of the air inlet adjustable throttle valve 41, and the outlet of the air inlet adjustable throttle valve 41 is directly connected with the inlet of the low-frequency high-speed switch valve 42; the sixth port o4 is connected with the rear pressure sensor 12; the large valve body is also provided with three seventh ports io, and the three seventh ports io, the fourth port i2, the second port o1 and the sixth port (o4) are communicated with each other in the valve body of the multi-way combination valve. The three seventh interfaces io are arbitrarily connected with the outlet of the low-frequency high-speed switch valve 42, the inlet of the safety valve 10 and the air passage of the soft robot 1 through pipes.

The valve hole circular sheet 101 is fixed on the large valve body 106 by the screw thread at the lower end of the radial hole rotary cover 103, a small sealing ring 105 is arranged between the valve hole circular sheet 101 and the large valve body 106 for end face sealing, and a large sealing ring 102 is arranged between the radial hole rotary cover 103 and the large valve body 106 for end face sealing; the lower part of the small hole in the center of the valve hole wafer 101 is a taper hole, the small hole in the center of the valve hole wafer 101, the taper hole and the taper hole on the large valve body 106 have coaxiality requirements, and the end part of the taper hole on the large valve body 106 is provided with a thread fastening seal of a detachable plug 104; the taper hole on the big valve body 106, the port o3 and the port i1 are communicated, and the big valve body 106, the valve hole wafer 101, the small sealing ring 105 and the radial hole rotary cover 103 form the small hole throttle valve 61.

The external pilot type reducing valve 2 is a reducing valve which introduces feedback control air pressure from the outside of a valve (an air inlet pipe of the soft robot 1) to a pilot valve core, the difference between the inlet pressure and the pressure of a downstream pressure-leading feedback pilot control port is large differential pressure, the downstream pressure-leading feedback pilot control air path is small in aperture and volume, and the pilot action air consumption is low.

According to the requirements of operation time and control precision, the orifice throttle valve 61 can replace the valve hole discs 101 with different orifice diameters, and the range of the orifice diameters is 0.05-2 mm.

In another scheme, an io, i2 port, an o1 port, an o4 port and four io ports are added, the seven ports are communicated, and an io pipe is connected with an inlet of the air outlet switch valve 83; or eight holes of two io, i2, o1, o4 and five io ports are added and communicated, and the two io ports are respectively connected with inlets of the air outlet switch valve 83 and the air path switch valve 92.

Example two

The embodiment of the invention also discloses a soft robot pneumatic system based on the choking principle, which is different from the first embodiment in that the second air inlet part is arranged differently:

referring to fig. 5, the second air inlet part comprises a small hole throttle valve 61, a high-frequency high-speed switch valve 62 and a second air inlet pipeline 63, wherein the second air inlet pipeline 63 is connected with the soft robot 1 and the air outlet end of the air inlet adjustable throttle valve 41; the orifice throttle valve 61 is provided in the second intake line 63 for controlling intake air at the second flow rate; the high-frequency high-speed switching valve 62 is disposed in the second air intake pipeline 63, and is configured to control opening and closing of air intake to the inner cavity of the soft robot 1.

The soft robot pneumatic system based on the congestion principle comprises an external pilot type pressure reducing valve 2, wherein the air inlet end of the external pilot type pressure reducing valve 2 is connected with an air source, compressed air of the air source is subjected to pressure reduction treatment through the external pilot type pressure reducing valve 2, the air outlet end of the air source outputs compressed air with stable pressure, and the compressed air treated by the external pilot type pressure reducing valve 2 is subjected to throttling treatment through an air inlet adjustable valve 41; the compressed air throttled by the air inlet adjustable throttle valve 41 is divided into two paths, and one path of compressed air enters the inner cavity of the soft robot 1 through a first air inlet pipeline 43; and one path is used for feeding air into the inner cavity of the soft robot 1 through a second air inlet pipeline 63. Controlling the first air inlet pipeline 43 to introduce air into the soft robot 1 at a first flow rate until the pressure in the inner cavity of the soft robot 1 approaches a target pressure; the first flow is set to be a large flow, and in an initial state or when the pressure in the inner cavity of the soft robot does not reach the target pressure, the first air inlet pipeline 43 supplies air to the inner cavity of the soft robot 1, and the soft robot 1 is driven to perform a quick response operation in a first mode (namely, a large flow mode). When the pressure of the inner cavity of the soft robot 1 reaches the target pressure, the second air inlet pipeline 63 is controlled to intake air into the soft robot 1 at a second flow rate until the pressure of the inner cavity reaches the target pressure. The second flow is set to be micro-flow, and the pressure of the inlet and the outlet of the small-hole throttle valve 61 is controlled to meet the choked flow state, so that the pressure of the inner cavity of the soft robot is accurately controlled to reach the target pressure, and the fine action of the soft robot is driven, such as the accurate control of the posture 1, the contact state and the like of the soft robot. The control gas circuit of the external pilot type pressure reducing valve 2 is connected with the inlet gas circuit of the soft robot 1, so that the second gas inlet part with a micro-flow gas circuit can reliably maintain a completely choked flow state for a long time.

Compressed air enters an inner cavity of the soft robot 1 to drive a feedback control air path of the external pilot type pressure reducing valve 2 to be communicated with an air inlet pipe of the soft robot 1; the rear pressure sensor 12, the inlet of the safety valve 10, the inlet of the air outlet switch valve 83 and the inlet of the vacuum path switch valve 92 are communicated with an air inlet pipe of the soft robot 1; the outlet of the air outlet switch valve 83 is directly communicated with the atmosphere, or is connected with the inlet of the air outlet adjustable throttle valve 82, and the outlet of the air outlet adjustable throttle valve 82 is communicated with the atmosphere; the pneumatic system of the soft robot is provided with or without a vacuum gas circuit consisting of a vacuum gas circuit switch valve 92 and a vacuum pump 93 or a vacuum tank, and the outlet of the vacuum gas circuit switch valve 92 is connected with the vacuum pump 93 or the vacuum tank.

The application of the pneumatic system is matched with a multi-way combination valve, the multi-way combination valve comprises a small-hole throttle valve 61 (in a double-dotted line frame in fig. 5), an air inlet adjustable throttle valve 41 and connecting pipelines, and as shown in fig. 6-8, an external pilot type pressure reducing valve 2 (not shown in the figure) is connected with a small valve body 107 through two pipelines; all gas circuits have been concentrated to little valve body 107, and the gas circuit is connected: the first interface i1 is connected with the outlet of the external pilot type pressure reducing valve 2 through a pipe, and the second interface o1 is connected with the inlet of the control air path of the external pilot type pressure reducing valve 2 through a pipe; the third port o2 is connected with the inlet of the high-frequency high-speed switch valve 62 through a pipe, and the fourth port i2 is connected with the outlet of the high-frequency high-speed switch valve 62 through a pipe; the fifth interface o3 is connected with the inlet of the low-frequency high-speed switch valve 42 through a pipe; the sixth port o4 pipe is connected with the rear pressure sensor 12; the small valve body is also provided with three seventh ports io, and the three seventh ports io, the fourth port i2, the second port o1 and the sixth port (o4) are communicated with each other in the valve body of the multi-way combination valve. The seventh interface io is arbitrarily connected with the outlet of the low-frequency high-speed switch valve 42, the inlet of the safety valve 10 and the air path of the soft robot 1 through pipes.

The valve hole circular sheet 101 is fixed on the small valve body 107 by the screw thread at the lower end of the radial hole rotary cover 103, the end face of the small sealing ring 105 is sealed between the valve hole circular sheet 101 and the small valve body 107, and the end face of the large sealing ring 102 is sealed between the radial hole rotary cover 103 and the small valve body 107; the lower part of the small hole in the center of the valve hole wafer 101 is a taper hole, the small hole in the center of the valve hole wafer 101, the taper hole and the taper hole on the small valve body 107 have coaxiality requirements, and the end part of the taper hole on the small valve body 107 is provided with a thread fastening seal of a detachable plug 104; the threads on the conical head throttling valve core 109, the locking thin nut 110 and the rhombic seat 111 are fine tooth adjusting threads, the upper hole and the lower hole of the rhombic seat 111 are fixed on the small valve body 107 through screws, the threads on the conical head throttling valve core 109 are locked by the locking thin nut 110 after being rotationally adjusted in place in the threaded hole on the rhombic seat 111, a fine sealing ring 112 is arranged between the rhombic seat 111 and the small valve body 107, the fine sealing ring 112 is used for sealing the end face of the rhombic seat 111 and also used for radially sealing the fine cylindrical section of the conical head throttling valve core 109, meanwhile, the small valve body 107 is provided with a small sealing ring 105, and the small sealing ring 105 is used for radially sealing the thick cylindrical section of the conical head throttling valve core 109; the outer end of a through hole which is connected with a taper hole on the small valve body 107, a clearance fit hole with the taper head throttle valve core 109 and an o3 hole is blocked by a non-detachable plug 108, and gas at an i1 hole on the small valve body 107 passes through a conical surface adjustable clearance (rotating the taper head throttle valve core 109) of the taper head throttle valve core 109, is communicated with the taper hole and an o3 hole and realizes flow regulation.

The small valve body 107, the valve hole wafer 101, the small sealing ring 105 and the radial hole rotary cover 103 form the small hole throttle valve 61; the small valve body 107, the cone head throttling valve core 109, the thin locking nut 110, the diamond-shaped seat 111, the fine sealing ring 112 and the small sealing ring 105 form the air inlet adjustable throttle valve 41.

The soft robot pneumatic system based on the choking principle in the embodiment is mainly applied to the fields of pneumatic soft robots and the like, such as pneumatic soft fingers and pneumatic artificial muscles, and overcomes the crawling defect when a cylinder is used because rubber sealing sliding friction does not exist; secondly, a high-flow gas path is controlled through a low-frequency high-speed switch valve 42, the response is sensitive, and the pressure of the inner cavity of the soft robot is initially controlled to be closer to the target pressure; thirdly, the final control precision of the pressure in the inner cavity of the soft robot 1 is high by controlling the high-frequency high-speed switch valve 62 due to the small output flow of the small-hole throttle valve 61; the high-frequency high-speed switch valve 62 is arranged on the air outlet side of the orifice throttle valve 61, the opening and closing of the high-frequency high-speed switch valve 62 does not influence the inlet pressure of the orifice throttle valve 61 instantly, and the mass flow of the orifice throttle valve 61 does not change instantly; and connecting a control port of the external pilot-operated pressure reducing valve with the inner cavity of the soft robot to control the maximum pressure of the inner cavity of the soft robot, so as to ensure the safety of the inner cavity of the soft robot in bearing, and simultaneously, adding a safety valve to further improve the safety of the soft robot in use. The pneumatic system has the advantages of good dynamic performance, sensitive response and high control precision, and simultaneously greatly improves the safety of the soft robot and reliably ensures the condition of a completely jammed state.

Has the following technical advantages:

based on the choking condition, the small-hole throttle valve 61 is applied to the field of pneumatic soft robots, particularly pneumatic soft fingers or pneumatic artificial muscles, and is convenient for mathematical modeling, numerical calculation and pressure control through mass flow parameters according to the principle that the mass flow of gas is constant.

And secondly, a micro-flow gas path and a large-flow gas path are connected in parallel, and under the feedback of a rear pressure sensor, when the target pressure is approached, the low-frequency high-speed switch valve 42 cuts off the large-flow gas path of the air inlet adjustable throttle valve 41, and simultaneously, the high-frequency high-speed switch valve 62 controls the on-off of the micro-flow gas path of the small-hole throttle valve 61 in a pulse mode, so that the pressure of an inner cavity of the pneumatic actuator, particularly the soft robot, is accurately controlled.

And thirdly, the high-frequency high-speed switch valve 62 is arranged on the outlet side of the small-hole throttle valve 61, and the inlet pressure of the small-hole throttle valve 61 is unchanged when the high-frequency high-speed switch valve 62 is opened, so that mathematical model establishment, dynamic analysis and flow control are facilitated.

Fourthly, an external pilot type reducing valve 2 is adopted, the difference between the inlet pressure and the pressure of a downstream pressure guiding feedback pilot control port is large differential pressure, the downstream pressure guiding feedback pilot control gas path is small in aperture and volume, and the pilot action gas consumption is low; the control gas circuit is connected to the gas inlet circuit of the soft robot, so that the driving pressure of the soft robot is lower than the bearing pressure of the soft robot, and the safety is good; particularly, the ratio of the outlet pressure to the inlet pressure of the orifice throttle valve 61 is less than 0.528, and the choke condition is satisfied, so that the orifice throttle valve 61 always works in the choke state.

A safety valve 10 is added, and the use safety of the soft robot is further improved.

Sixthly, a vacuum gas circuit is arranged, so that the soft robot acts reversely, and the action space is larger.

And seventhly, in the continuous process of the mass flow mode, the soft robot made of the elastic rubber material can inhibit the vibration of the soft robot in the motion process by dynamically controlling the opening and closing of the high-frequency high-speed switch valve 62 according to an algorithm.

The pneumatic system of the invention aims to: the low-frequency high-speed switch valve 42 is controlled to quickly approach the control target pressure as much as possible in a large flow mode, the mass flow step property at the opening and closing moment of the orifice throttle valve 61 in a micro flow mode is good, and the pulse control effect of the mass flow is achieved by opening and closing the high-frequency high-speed switch valve 62, so that the high precision of the pressure control is achieved.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.