Control system for fluid actuator and flexible robotic arm

Abstract

This application relates to the field of software drive and control technology, and provides a drive and control system for a fluid actuator and a flexible robotic arm. The system includes: a fluid actuator, a fluid drive source, a fluid channel connecting the fluid actuator and the fluid drive source, and a fluid control valve disposed on the fluid channel. The fluid actuator can control the amount of fluid in its internal cavity through the fluid drive source and the fluid control valve to form a pressure difference change inside and outside the fluid actuator, thereby achieving extension and / or compression deformation. The fluid drive source includes: a first fluid source and a second fluid source having a relative fluid pressure difference, and a pressure difference regulating source with a fluid pressure between or outside the first fluid source and the second fluid source. The fluid actuator can increase or decrease the amount of fluid in its internal cavity through the first fluid source or the second fluid source. Through this application embodiment, the drive and control efficiency of the fluid drive source can be improved during the process of increasing or decreasing the amount of fluid in the internal cavity of the fluid actuator.

Description

Technical Field

[0001] This application belongs to the field of software drive and control technology, and in particular relates to a drive and control system for a fluid actuator and a flexible robotic arm. Background Technology

[0002] A flexible robotic arm is formed by stacking several fluid actuators (i.e., soft muscles) in parallel and / or in series, and the movement is achieved by driving the fluid actuators to extend and contract through a fluid drive source. In the prior art, the fluid drive source in the drive control system of the flexible robotic arm uses a two-bus design, that is, using a positive pressure source and a negative pressure source as the fluid drive source to drive the fluid actuator.

[0003] When the fluid drive source with a two-bus design increases the positive or negative pressure inside the fluid actuator cavity, the fluid drive source generally does not have problems. However, when it is necessary to reduce the positive or negative pressure inside the fluid actuator cavity, the driving efficiency of the fluid source in the fluid drive source may be affected. For example, when the positive pressure of the fluid actuator inside the cavity needs to be reduced, the valve of the negative pressure source needs to be opened to connect the negative pressure source to the fluid actuator. The positive pressure inside the fluid actuator will enter the negative pressure source, causing the pressure in the negative pressure source to increase rapidly. In a short time, the fluid pressure in the negative pressure source may even be higher than the working pressure of the fluid actuator. At this time, the negative pressure source loses its function and seriously affects the driving efficiency of the negative pressure source in the fluid drive source. Summary of the Invention

[0004] In view of this, embodiments of this application provide a drive and control system for a fluid actuator and a flexible robotic arm, which can improve the drive and control efficiency of the fluid drive source.

[0005] A first aspect of this application provides a drive and control system for a fluid actuator, comprising: a fluid actuator, a fluid drive source, a fluid channel connecting the fluid actuator and the fluid drive source, and a fluid control valve disposed on the fluid channel. The fluid actuator can control the amount of fluid in its internal cavity through the fluid drive source and the fluid control valve to form a pressure difference change inside and outside the fluid actuator, thereby realizing extension and / or compression deformation.

[0006] The fluid drive source includes: a first fluid source and a second fluid source having a relative fluid pressure difference, and a pressure difference regulating source with a fluid pressure between or outside the first fluid source and the second fluid source; the fluid actuator can increase or decrease the fluid volume in its internal cavity through the first fluid source or the second fluid source;

[0007] When the fluid pressure of the differential pressure regulating source is between the first fluid source and the second fluid source, during the process of increasing or decreasing the fluid volume in the internal cavity of the fluid actuator, the differential pressure regulating source can output / input fluid flowing from the fluid actuator to the first fluid source or the second fluid source in the forward / reverse direction and corresponding to the differential pressure portion, so as to reduce the original fluid pressure change of the first fluid source or the second fluid source.

[0008] When the fluid pressure of the differential pressure regulating source is outside the first fluid source and the second fluid source, during the process of increasing or decreasing the fluid volume in the internal cavity of the fluid actuator, the differential pressure regulating source can adjust the forward / reverse flow velocity of the fluid in the internal cavity of the fluid actuator between the first fluid source and the second fluid source by increasing the pressure difference with the first fluid source or the second fluid source.

[0009] A second aspect of this application provides a flexible robotic arm, which is composed of a plurality of fluid actuators stacked together, and the fluid actuators are driven and controlled based on the drive and control system of the fluid actuators described in the first aspect.

[0010] Compared with the prior art, the fluid actuator drive control system and flexible robotic arm provided in this application include, in addition to a first fluid source and a second fluid source with a relative fluid pressure difference, a pressure differential regulating source with a fluid pressure between or outside the first fluid source and the second fluid source. On the one hand, when the fluid pressure of the pressure differential regulating source is between the first fluid source and the second fluid source, during the increase or decrease of fluid volume in the internal cavity of the fluid actuator, the pressure differential regulating source can output / input flow from the fluid actuator to the first fluid source or the second fluid source in the forward / reverse direction, corresponding to the pressure difference portion. The differential pressure regulating source can reduce the original fluid pressure changes of the first or second fluid source, thereby reducing the impact on the driving efficiency of the first and second fluid sources in the fluid drive source. On the other hand, when the fluid pressure of the differential pressure regulating source is outside the first and second fluid sources, during the process of increasing or decreasing the fluid volume in the internal cavity of the fluid actuator, the differential pressure regulating source can increase the pressure difference with the first or second fluid source to adjust the forward / reverse flow velocity of the fluid in the internal cavity of the fluid actuator between the first and second fluid sources, thereby increasing the driving speed of the fluid actuator. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0012] Figure 1 This is a schematic diagram of the drive and control system of the fluid actuator provided in an embodiment of this application;

[0013] Figure 2 This is another schematic diagram of the drive and control system of the fluid actuator provided in the embodiments of this application;

[0014] Figure 3 This is another schematic diagram of the drive and control system of the fluid actuator provided in the embodiments of this application;

[0015] Figure 4 This is a schematic diagram of the structure of a fluid actuator provided in an embodiment of this application. Detailed Implementation

[0016] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0017] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0018] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0020] To facilitate understanding, the following first describes the definitions of positive pressure, negative pressure, and the characteristics of positive and negative pressure in the application:

[0021] Positive pressure refers to a state in which the pressure inside a system is higher than the external environment (atmospheric pressure) relative to the surrounding environment.

[0022] Negative pressure refers to a state in which the pressure inside a system is lower than the external environment (atmospheric pressure) relative to the surrounding environment.

[0023] Positive and negative pressure exhibit a significant asymmetry in physics. Specifically, reducing pressure requires more energy and time to achieve the same pressure difference compared to increasing it. Furthermore, compared to air pressure (one standard atmosphere), negative pressure can drop to less than one standard atmosphere, while the range of positive pressure is much wider. This is primarily because, in physics, pressure differences can be used to drive fluids from high-pressure to low-pressure regions. When we need to extract liquids or gases, we typically create a negative pressure in a low-pressure region, allowing the liquid or gas to flow from the high-pressure region to the low-pressure region. Maintaining this negative pressure requires energy to extract and sustain it. In contrast, applying positive pressure only requires sufficient pressure to push the liquid or gas from a low-pressure region to a high-pressure region. Because positive pressure propels the fluid by providing additional pressure, it typically consumes less energy than applying negative pressure; that is, the energy conversion efficiency of applying negative pressure is much lower than that of applying positive pressure, often requiring more energy to maintain the negative pressure state.

[0024] At normal atmospheric pressure, there are a vast number of gas molecules. However, in a vacuum, most or even all of these gas molecules need to be extracted. This means that the kinetic energy of a large number of gas molecules must be overcome to remove them from the container. In contrast, applying positive pressure only increases the pressure of the gas inside the container, without requiring the complete removal of a large number of gas molecules.

[0025] In existing technologies, when a fluid actuator with a two-bus design reduces the positive or negative pressure of the internal cavity, the driving efficiency of the fluid source may be affected. For example, when a fluid actuator with a certain positive pressure needs to reduce that pressure, a negative pressure valve opens, connecting the actuator to the negative pressure source. The positive pressure in the actuator then enters the negative pressure source. It can be assumed that the gas in the negative pressure source is an ideal gas. According to the Clapeyron equation PV = nRT (where P represents the state parameter pressure, V is volume, n is the amount of gas, T is the absolute temperature, and R is a constant), with constant temperature and volume, a rapid increase in the amount of gas leads to a rapid decrease in pressure. This causes the pressure in the negative pressure source to rise rapidly, even exceeding the operating pressure of the fluid actuator using negative pressure. In this case, the negative pressure source loses its function, severely affecting its driving efficiency. The driving system for the fluid actuator provided in this application solves these problems.

[0026] Please see Figure 1 , Figure 1A schematic diagram of the drive and control system of the fluid actuator 10 provided in this application includes a fluid actuator 10, a fluid drive source 20, a fluid channel 30 connecting the fluid actuator 10 and the fluid drive source 20, and a fluid control valve 40 disposed on the fluid channel 30. The fluid actuator 10 can control the amount of fluid in its internal cavity through the fluid drive source 20 and the fluid control valve 40 to form a pressure difference change inside and outside the fluid actuator 10, thereby realizing extension and / or compression deformation.

[0027] Specifically, the fluid drive source 20 includes: a first fluid source 201 and a second fluid source 202 having a relative fluid pressure difference, and a pressure difference regulating source 203 with a fluid pressure between or outside the first fluid source 201 and the second fluid source 202; the fluid actuator 10 can increase or decrease the amount of fluid in its internal cavity through the first fluid source 201 or the second fluid source 202.

[0028] Among them, such as Figure 1 As shown, the first fluid source 201 is controlled by the first fluid control valve 401, the second fluid source 202 is controlled by the second fluid control valve 402, and the differential pressure regulating source 203 is controlled by the third fluid control valve 403.

[0029] In some embodiments, the fluid pressure of the differential pressure regulating source 203 is pre-set between the first fluid source 201 and the second fluid source 202, or the fluid pressure of the differential pressure regulating source 203 is pre-set outside the first fluid source 201 and the second fluid source 202. In other embodiments, the fluid pressure in the differential pressure regulating source 203 can be dynamically adjusted to the required fluid pressure according to the current pressure requirement of the fluid actuator 10. For example, when the fluid actuator 10 needs to perform compression deformation or extension deformation, the fluid pressure of the differential pressure regulating source 203 is set between the first fluid source 201 and the second fluid source 202; when the fluid actuator 10 needs to drive and accelerate, the fluid pressure of the differential pressure regulating source 203 is set outside the first fluid source 201 and the second fluid source 202.

[0030] The following describes the drive and control system of the fluid actuator 10 in this embodiment when the fluid pressure of the differential pressure regulating source 203 is between the first fluid source 201 and the second fluid source 202:

[0031] When the fluid pressure of the differential pressure regulating source 203 is between the first fluid source 201 and the second fluid source 202, during the process of increasing or decreasing the fluid volume in the internal cavity of the fluid actuator 10, the differential pressure regulating source 203 can output / input fluid flowing from the fluid actuator 10 to the first fluid source 201 or the second fluid source 202 in the forward / reverse direction and corresponding to the differential pressure portion, so as to reduce the original fluid pressure change of the first fluid source 201 or the second fluid source 202.

[0032] In this embodiment, the fluid actuator 10 can be installed on a robotic arm, and the drive control system of the fluid actuator 10 can be the drive control system of the robotic arm. Furthermore, the robotic arm can be a robotic arm on a robot, and the robot can specifically be a charging robot, a handling robot, a sweeping robot, etc.

[0033] When the fluid pressure of the differential pressure regulating source 203 is between the first fluid source 201 and the second fluid source 202, the following situations exist:

[0034] First scenario:

[0035] The fluid pressure of the first fluid source 201 is positive, the fluid pressure of the second fluid source 202 is negative, and the fluid pressure of the differential pressure regulating source 203 is atmospheric pressure or a negative pressure between atmospheric pressure and the second fluid source 202; wherein, in this embodiment of the application, when the fluid pressure of the differential pressure regulating source 203 is atmospheric pressure, the differential pressure regulating source 203 can be connected to the atmosphere.

[0036] At this time, when the fluid actuator 10 is compressed and deformed, during the process of the fluid pressure in the internal cavity of the fluid actuator 10 switching from positive pressure to negative pressure, the fluid corresponding to the pressure difference between the first fluid source 201 and the pressure difference regulating source 203 can be pre-flowed into the pressure difference regulating source 203 through the opening and closing control of the corresponding fluid control valve 40, and then the fluid can flow into the second fluid source 202 in a negative direction to reduce the original fluid pressure change of the second fluid source 202.

[0037] The opening and closing control of the aforementioned fluid control valve 40 includes:

[0038] Open the fluid control valve 40 for controlling the differential pressure regulating source 203. After the fluid corresponding to the pressure difference between the first fluid source 201 and the differential pressure regulating source 203 flows negatively into the differential pressure regulating source 203, close the fluid control valve 40 for controlling the differential pressure regulating source 203, and open the fluid control valve 40 for controlling the second fluid source 202 until the fluid pressure in the fluid actuator 10 reaches the specified negative pressure value, and then close the fluid control valve 40 for controlling the second fluid source 202.

[0039] Specifically, when the fluid actuator 10 needs to be compressed and deformed, the third fluid control valve 403 is first opened. At this time, the fluid channel 30 between the fluid actuator 10 and the differential pressure regulating source 203 is connected. The fluid in the internal cavity of the fluid actuator 10 is currently at positive pressure from the first fluid source 201. It can be understood that the fluid pressure in the internal cavity of the fluid actuator 10 is the fluid pressure from the first fluid source 201. Furthermore, the fluid pressure of the differential pressure regulating source 203 is atmospheric pressure or a negative pressure between atmospheric pressure and the second fluid source 202. Therefore, after opening the third fluid control valve 403, the fluid actuator 10's internal cavity... The fluid in the pressure difference section between the first fluid source 201 and the pressure difference regulating source 203 will automatically flow into the pressure difference regulating source 203 in the negative direction, reducing the positive pressure inside the fluid actuator 10. At this time, the third fluid control valve 403 is closed and the second fluid control valve 402 is opened. Since the positive pressure inside the fluid actuator 10 is reduced, relative to the original fluid pressure inside the fluid actuator 10, connecting the fluid actuator 10 with the second fluid source 202 can reduce the original fluid pressure change of the second fluid source 202, thereby reducing the impact on the driving efficiency of the second fluid source 202 when the fluid actuator 10 is compressed and deformed.

[0040] The second scenario:

[0041] The fluid pressure of the first fluid source 201 is positive, the fluid pressure of the second fluid source 202 is negative, and the fluid pressure of the differential pressure regulating source 203 is atmospheric pressure or a positive pressure between atmospheric pressure and the first fluid source 201.

[0042] At this time, when the fluid actuator 10 extends and deforms, during the process of the fluid pressure in the internal cavity of the fluid actuator 10 switching from negative pressure to positive pressure, the fluid corresponding to the pressure difference between the second fluid source 202 and the pressure difference regulating source 203 can be pre-flowed into the pressure difference regulating source 203 through the opening and closing control of the corresponding fluid control valve 40, and then the fluid can flow forward to the first fluid source 201 to reduce the original fluid pressure change of the first fluid source 201.

[0043] The opening and closing control of the aforementioned fluid control valve 40 includes:

[0044] Open the fluid control valve 40 for controlling the differential pressure regulating source 203. After the fluid corresponding to the pressure difference between the second fluid source 202 and the differential pressure regulating source 203 flows forward into the differential pressure regulating source 203, close the fluid control valve 40 for controlling the differential pressure regulating source 203 and open the fluid control valve 40 for controlling the first fluid source 201 until the fluid pressure in the fluid actuator 10 reaches the specified positive pressure value, and then close the fluid control valve 40 for controlling the first fluid source 201.

[0045] Specifically, when the fluid actuator 10 needs to extend and deform, the third fluid control valve 403 is first opened. At this time, the fluid channel 30 between the fluid actuator 10 and the differential pressure regulating source 203 is connected. The fluid in the internal cavity of the fluid actuator 10 is currently under negative pressure from the second fluid source 202. It can be understood that the fluid pressure in the internal cavity of the fluid actuator 10 is the fluid pressure from the second fluid source 202. Furthermore, the fluid pressure of the differential pressure regulating source 203 is atmospheric pressure or a positive pressure between atmospheric pressure and the first fluid source 201. Therefore, after opening the third fluid control valve 403, the fluid actuator 10's internal cavity... The fluid in the pressure difference section between the second fluid source 202 and the pressure difference regulating source 203 will automatically flow in the positive direction into the pressure difference regulating source 203, reducing the positive pressure inside the fluid actuator 10. At this time, the third fluid control valve 403 is closed and the first fluid control valve 401 is opened. Since the negative pressure inside the fluid actuator 10 is reduced, relative to the original fluid pressure inside the fluid actuator 10, connecting the fluid actuator 10 with the first fluid source 201 can reduce the original fluid pressure change of the first fluid source 201, thereby reducing the impact on the driving efficiency of the first fluid source 201 when the fluid actuator 10 is stretched and deformed.

[0046] The third scenario:

[0047] The fluid pressure of the first fluid source 201 is positive, the fluid pressure of the second fluid source 202 is negative, and the fluid pressure of the differential pressure regulating source 203 is atmospheric pressure.

[0048] When the fluid pressure of the fluid actuator 10 is a first positive pressure, and the fluid pressure of the fluid actuator 10 needs to be reduced from the first positive pressure to a second positive pressure, the fluid control valve 40 for controlling the differential pressure regulating source 203 is opened until the fluid pressure of the fluid actuator 10 reaches the second positive pressure, and then the fluid control valve 40 of the differential pressure regulating source 203 is closed.

[0049] Specifically, the fluid pressure inside the cavity of the current fluid actuator 10 is positive. When it is necessary to reduce the positive pressure of the internal cavity, and the required air pressure after the reduction is also positive, the third fluid control valve 403 can be opened to connect the fluid actuator 10 with the differential pressure regulating source 203. Since the pressure of the differential pressure regulating source 203 is atmospheric pressure, the positive pressure inside the cavity of the fluid actuator 10 can be reduced directly through the differential pressure regulating source 203 without the need to use the second fluid source 202, thus avoiding a reduction in the driving efficiency of the second fluid source 202.

[0050] When the fluid pressure of the fluid actuator 10 is a first negative pressure, and the fluid pressure of the fluid actuator 10 needs to be increased from the first negative pressure to a second negative pressure, the fluid control valve 40 for controlling the differential pressure regulating source 203 is opened until the fluid pressure of the fluid actuator 10 reaches the second negative pressure, and then the fluid control valve 40 of the differential pressure regulating source 203 is closed, wherein the absolute value of the first negative pressure is greater than the absolute value of the second negative pressure.

[0051] Specifically, the fluid pressure inside the fluid actuator 10 is currently negative. When it is necessary to reduce the negative pressure inside the fluid actuator 10, and the required air pressure after the reduction is also negative, the third fluid control valve 403 can be opened to connect the fluid actuator 10 with the differential pressure regulating source 203. Since the pressure of the differential pressure regulating source 203 is atmospheric pressure, the positive pressure inside the fluid actuator 10 can be reduced directly through the differential pressure regulating source 203 without using the first fluid source 201, thus avoiding a reduction in the driving efficiency of the first fluid source 201.

[0052] When the fluid pressure of the differential pressure regulating source 203 is between the first fluid source 201 and the second fluid source 202, the following situations exist:

[0053] First scenario:

[0054] The fluid pressure of the first fluid source 201 is positive, the fluid pressure of the second fluid source 202 is atmospheric pressure or negative, and the fluid pressure of the differential pressure regulating source 203 is greater in absolute value than the negative pressure of the second fluid source 202; or, the first fluid source 201 is atmospheric pressure, the second fluid source 202 is negative, and the differential pressure regulating source 203 is greater in absolute value than the negative pressure of the second fluid source 202.

[0055] When the fluid actuator 10 is compressed and deformed, the pressure difference between the negative pressure end of the fluid actuator 10 and the first fluid source 201 can be increased by controlling the opening and closing of the differential pressure regulating source 203 and the corresponding fluid control valve 40, so as to increase the negative flow velocity of the fluid in the internal cavity of the fluid actuator 10 between the second fluid source 202.

[0056] The differential pressure regulating source 203 and the second fluid source 202 are connected in parallel or in series to form the negative pressure end. When the differential pressure regulating source 203 and the second fluid source 202 are connected in parallel, the structure of the drive and control system of the fluid actuator 10 is as follows: Figure 1 As shown, when the differential pressure regulating source 203 is connected in series with the second fluid source 202, the structure of the drive and control system of the fluid actuator 10 is as follows. Figure 2 As shown.

[0057] When the fluid actuator 10 is compressed and deformed, the opening and closing control of the fluid control valve 40 includes:

[0058] Open the fluid control valve 40 of the differential pressure regulating source 203 and the second fluid source 202, and increase the pressure difference between the negative pressure end and the first fluid source 201 through the differential pressure regulating source 203, so as to increase the negative flow velocity of the fluid in the internal cavity of the fluid actuator 10 between the second fluid source 202.

[0059] Specifically, such as Figure 1 or Figure 2 As shown, the second fluid control valve 402 and the third fluid control valve 403 are opened, so that the fluid actuator 10 is connected to the second fluid source 202 and the differential pressure regulating source 203.

[0060] In this embodiment, the faster the fluid in the internal cavity of the fluid actuator 10 flows in the negative direction between the second fluid source 202, the faster the driving speed of the fluid actuator 10. In the prior art, the negative pressure end of the fluid actuator 10 is only the second fluid source 202. However, the negative pressure end of this embodiment is composed of the second fluid source 202 and the differential pressure regulating source 203. The absolute value of the differential pressure regulating source 203 is greater than the negative pressure of the second fluid source 202. Therefore, compared with the negative pressure end of the prior art, the negative pressure end of this application has a larger pressure difference between the negative pressure end and the first fluid source 201, and a larger pressure difference between the negative pressure end and the internal cavity of the fluid actuator. This increases the negative flow velocity of the fluid in the internal cavity of the fluid actuator 10 between the second fluid source 202, thereby increasing the negative pressure driving speed of the fluid actuator 10.

[0061] Furthermore, when the normal driving fluid actuator 10 only needs to be driven under negative pressure (i.e., there is no need to increase the driving speed), only the second fluid control valve 402 needs to be opened during driving, without opening the third fluid control valve 403.

[0062] The second scenario:

[0063] The fluid pressure of the first fluid source 201 is atmospheric pressure or positive pressure, the fluid pressure of the second fluid source 202 is negative pressure, and the fluid pressure of the differential pressure regulating source 203 is greater than the positive pressure of the first fluid source 201; or, the fluid pressure of the first fluid source 201 is positive pressure, the fluid pressure of the second fluid source 202 is atmospheric pressure, and the fluid pressure of the differential pressure regulating source 203 is greater than the positive pressure of the first fluid source.

[0064] When the fluid actuator 10 extends and deforms, the pressure difference between the positive pressure end of the fluid actuator 10 and the second fluid source 202 can be increased by controlling the opening and closing of the differential pressure regulating source 203 and the corresponding fluid control valve 40, so as to increase the forward flow velocity of the fluid in the internal cavity of the fluid actuator 10 between the first fluid source 201.

[0065] The differential pressure regulating source 203 is connected in parallel or in series with the first fluid source 201 to form the positive pressure end; when the differential pressure regulating source 203 is connected in parallel with the first fluid source 201, the structure of the drive and control system of the fluid actuator 10 is as follows. Figure 1 As shown, when the differential pressure regulating source 203 is connected in series with the first fluid source 201, the structure of the drive and control system of the fluid actuator 10 is as follows. Figure 3 As shown.

[0066] When the fluid actuator 10 extends and deforms, the opening and closing control of the fluid control valve 40 includes:

[0067] Open the pressure differential regulating source 203 and the fluid control valve 40 of the first fluid source 201, and increase the pressure differential between the positive pressure end and the second fluid source 202 through the pressure differential regulating source 203, so as to increase the forward flow velocity of the fluid in the internal cavity of the fluid actuator 10 between the first fluid source 201.

[0068] Specifically, such as Figure 1 or Figure 3 As shown, the first fluid control valve 401 and the third fluid control valve 403 are opened, so that the fluid actuator 10 is connected to the first fluid source 201 and the differential pressure regulating source 203.

[0069] In this embodiment, the faster the forward flow velocity of the fluid in the internal cavity of the fluid actuator 10 between the first fluid source 201, the faster the driving speed of the fluid actuator 10. In the prior art, the positive pressure end of the fluid actuator 10 is only the first fluid source 201. However, the positive pressure end of this embodiment is composed of the first fluid source 201 and the differential pressure regulating source 203. The differential pressure regulating source 203 has a higher positive pressure than the second fluid source 202. Therefore, compared with the positive pressure end of the prior art, the positive pressure end of this application has a larger pressure difference between the positive pressure end and the second fluid source 202, and also a larger pressure difference between the positive pressure end and the internal cavity of the fluid actuator. This increases the forward flow velocity of the fluid in the internal cavity of the fluid actuator 10 between the first fluid source 201, thereby increasing the positive pressure driving speed of the fluid actuator 10.

[0070] Furthermore, when the normal driving fluid actuator 10 only needs to use positive pressure normal driving (i.e., there is no need to increase the driving speed), at this time, only the first fluid control valve 401 needs to be opened during driving, and the third fluid control valve 403 does not need to be opened.

[0071] In this embodiment, when the first fluid source 201 is under positive pressure, it is specifically a cylinder storing the corresponding positive pressure; when the first fluid source 201 is under atmospheric pressure, it is specifically a cylinder storing atmospheric pressure, or it can be directly connected to the atmosphere. When the second fluid source 202 is under negative pressure, it is specifically a cylinder storing the corresponding negative pressure; when the second fluid source 202 is under atmospheric pressure, it is specifically a cylinder storing atmospheric pressure, or it can be directly connected to the atmosphere. When the differential pressure regulating source 203 is under positive pressure, it is specifically a cylinder storing the corresponding positive pressure; when the differential pressure regulating source 203 is under negative pressure, it is specifically a cylinder storing the corresponding negative pressure; when the differential pressure regulating source 203 is under atmospheric pressure, it is specifically a cylinder storing atmospheric pressure, or it can be directly connected to the atmosphere.

[0072] Due to the asymmetry of positive and negative pressure, the cylinder of the positive pressure source can store positive pressure with a large pressure difference compared to standard atmospheric pressure, while the cylinder of the negative pressure source can only store negative pressure with a small pressure difference compared to standard atmospheric pressure (close to one atmosphere).

[0073] Furthermore, the fluid actuator 10 in this application is also provided with a pressure monitor, which is used to monitor the fluid pressure in the fluid actuator 10 in real time when the fluid actuator 10 increases or decreases the pressure. When the fluid pressure is detected to reach the specified pressure, the drive control system of the fluid actuator 10 is notified to stop the operation of increasing or decreasing the pressure of the fluid actuator 10.

[0074] Furthermore, this application also provides a flexible robotic arm, which is composed of a plurality of fluid actuators 10 stacked together, and the fluid actuators 10 are driven and controlled based on the aforementioned fluid actuator drive and control system.

[0075] In some implementations, the structure of the fluid actuator 10 provided in this application is as follows: Figure 4 As shown.

[0076] In summary, on the one hand, when the fluid pressure of the differential pressure regulating source 203 is between the first fluid source 201 and the second fluid source 202, during the process of increasing or decreasing fluid volume in the internal cavity of the fluid actuator 10, the differential pressure regulating source 203 can output / input fluid flowing from the fluid actuator 10 to the first fluid source 201 or the second fluid source 202 in the forward / reverse direction, corresponding to the differential pressure portion, to reduce the original fluid pressure change of the first fluid source 201 or the second fluid source 202, thereby reducing the impact on the first fluid source 201 and the second fluid source 202 in the fluid drive source. The influence of the two fluid sources 202 on the driving efficiency; on the other hand, when the fluid pressure of the differential pressure regulating source 203 is outside the first fluid source 201 and the second fluid source 202, during the process of increasing or decreasing the fluid volume in the internal cavity of the fluid actuator 10, the differential pressure regulating source 203 can increase the pressure difference with the first fluid source 201 or the second fluid source 202 to adjust the forward / reverse flow speed of the fluid in the internal cavity of the fluid actuator 10 between the first fluid source 201 and the second fluid source 202, thereby increasing the driving speed of the fluid actuator 10.

[0077] The embodiments described above are only used to illustrate the technical solutions of this application, and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A drive system for a fluid actuator, characterized by include: A fluid actuator, a fluid drive source, a fluid channel connecting the fluid actuator and the fluid drive source, and a fluid control valve disposed on the fluid channel. The fluid actuator can control the amount of fluid in its internal cavity through the fluid drive source and the fluid control valve to form a pressure difference change inside and outside the fluid actuator, thereby achieving extension and / or compression deformation. The fluid drive source includes: a first fluid source and a second fluid source having a relative fluid pressure difference, and a pressure difference regulating source with a fluid pressure between or outside the first fluid source and the second fluid source; the fluid actuator can increase or decrease the fluid volume in its internal cavity through the first fluid source or the second fluid source; When the fluid pressure of the differential pressure regulating source is between the first fluid source and the second fluid source, during the process of increasing or decreasing the fluid volume in the internal cavity of the fluid actuator, the differential pressure regulating source can output / input fluid flowing from the fluid actuator to the first fluid source or the second fluid source in the forward / reverse direction and corresponding to the differential pressure portion, so as to reduce the original fluid pressure change of the first fluid source or the second fluid source. When the fluid pressure of the differential pressure regulating source is outside the first fluid source and the second fluid source, during the process of increasing or decreasing the fluid volume in the internal cavity of the fluid actuator, the differential pressure regulating source can adjust the forward / reverse flow velocity of the fluid in the internal cavity of the fluid actuator between the first fluid source and the second fluid source by increasing the pressure difference with the first fluid source or the second fluid source.

2. The system according to claim 1, characterized in that, The fluid pressure of the first fluid source is positive, the fluid pressure of the second fluid source is negative, and the fluid pressure of the differential pressure regulating source is atmospheric pressure or a negative pressure between atmospheric pressure and the second fluid source. When the fluid actuator is compressed and deformed, during the process of the fluid pressure in the internal cavity of the fluid actuator switching from positive pressure to negative pressure, the fluid corresponding to the pressure difference between the first fluid source and the pressure difference regulating source can be pre-flowed into the pressure difference regulating source in a negative direction through the opening and closing control of the corresponding fluid control valve, and then the fluid can flow into the second fluid source in a negative direction to reduce the original fluid pressure change of the second fluid source.

3. The system according to claim 2, characterized in that, When the fluid actuator compresses and deforms, the opening and closing control of the fluid control valve includes: Open the fluid control valve for controlling the differential pressure regulating source. After the fluid corresponding to the pressure difference between the first fluid source and the differential pressure regulating source flows negatively into the differential pressure regulating source, close the fluid control valve for controlling the differential pressure regulating source and open the fluid control valve for controlling the second fluid source until the fluid pressure in the fluid actuator reaches the specified negative pressure value, then close the fluid control valve for controlling the second fluid source.

4. The system according to claim 1, characterized in that, The fluid pressure of the first fluid source is positive, the fluid pressure of the second fluid source is negative, and the fluid pressure of the differential pressure regulating source is atmospheric pressure or a positive pressure between atmospheric pressure and the first fluid source. When the fluid actuator extends and deforms, during the process of the fluid pressure in the internal cavity of the fluid actuator switching from negative pressure to positive pressure, the fluid corresponding to the pressure difference between the second fluid source and the pressure difference regulation source can be pre-flowed into the pressure difference regulation source through the opening and closing control of the corresponding fluid control valve, and then the fluid can flow forward to the first fluid source to reduce the original fluid pressure change of the first fluid source.

5. The system according to claim 4, characterized in that, When the fluid actuator extends and deforms, the opening and closing control of the fluid control valve includes: Open the fluid control valve for controlling the differential pressure regulating source. After the fluid corresponding to the pressure difference between the second fluid source and the differential pressure regulating source flows forward into the differential pressure regulating source, close the fluid control valve for controlling the differential pressure regulating source and open the fluid control valve for controlling the first fluid source until the fluid pressure in the fluid actuator reaches the specified positive pressure value, then close the fluid control valve for controlling the first fluid source.

6. The system according to claim 1, characterized in that, The fluid pressure of the first fluid source is positive, the fluid pressure of the second fluid source is atmospheric pressure or negative, and the fluid pressure of the differential pressure regulating source is greater than the negative pressure of the second fluid source in absolute value; or, the first fluid source is atmospheric pressure, the second fluid source is negative, and the differential pressure regulating source is greater than the negative pressure of the second fluid source in absolute value. When the fluid actuator is compressed and deformed, the pressure difference between the negative pressure end of the fluid actuator and the first fluid source can be increased by controlling the opening and closing of the differential pressure adjustment source and the corresponding fluid control valve, so as to increase the negative flow velocity of the fluid in the internal cavity of the fluid actuator between the second fluid source.

7. The system according to claim 6, characterized in that, The differential pressure regulating source and the second fluid source are connected in parallel or in series to form the negative pressure end; When the fluid actuator accelerates under negative pressure, the opening and closing control of the fluid control valve includes: Open the fluid control valves of the differential pressure regulating source and the second fluid source, and increase the pressure difference between the negative pressure end and the first fluid source through the differential pressure regulating source, so as to increase the negative flow velocity of the fluid in the internal cavity of the fluid actuator between the second fluid source.

8. The system according to claim 1, characterized in that, The fluid pressure of the first fluid source is atmospheric pressure or positive pressure, the fluid pressure of the second fluid source is negative pressure, and the fluid pressure of the differential pressure regulating source is greater than the positive pressure of the first fluid source; or, the fluid pressure of the first fluid source is positive pressure, the fluid pressure of the second fluid source is atmospheric pressure, and the fluid pressure of the differential pressure regulating source is greater than the positive pressure of the first fluid source. When the fluid actuator extends and deforms, the pressure difference between the positive pressure end of the fluid actuator and the second fluid source can be increased by controlling the opening and closing of the differential pressure regulating source and the corresponding fluid control valve, so as to increase the forward flow velocity of the fluid in the internal cavity of the fluid actuator between the first fluid source.

9. The system according to claim 8, characterized in that, The differential pressure regulating source is connected in parallel or in series with the first fluid source to form the positive pressure end; When the fluid actuator accelerates under positive pressure, the opening and closing control of the fluid control valve includes: Open the fluid control valves of the differential pressure regulating source and the first fluid source, and increase the pressure difference between the positive pressure end and the second fluid source through the differential pressure regulating source, so as to increase the forward flow velocity of the fluid in the internal cavity of the fluid actuator between the first fluid source.

10. The system according to claim 1, characterized in that, The fluid pressure of the first fluid source is positive, the fluid pressure of the second fluid source is negative, and the fluid pressure of the differential pressure regulating source is atmospheric pressure. When the fluid pressure of the fluid actuator is a first positive pressure, and the fluid pressure of the fluid actuator needs to be reduced from the first positive pressure to a second positive pressure, the fluid control valve for controlling the differential pressure regulating source is opened until the fluid pressure of the fluid actuator reaches the second positive pressure, and then the fluid control valve of the differential pressure regulating source is closed. When the fluid pressure of the fluid actuator is a first negative pressure, and the fluid pressure of the fluid actuator needs to be increased from the first negative pressure to a second negative pressure, the fluid control valve for controlling the differential pressure regulating source is opened until the fluid pressure of the fluid actuator reaches the second negative pressure, and then the fluid control valve of the differential pressure regulating source is closed, wherein the absolute value of the first negative pressure is greater than the absolute value of the second negative pressure.

11. A flexible robotic arm, characterized in that, The flexible robotic arm is composed of a plurality of fluid actuators stacked together, and the fluid actuators are driven and controlled based on the drive and control system of the fluid actuators according to any one of claims 1-10.

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