JPH03249401A - Pneumatic driving device - Google Patents

Abstract

PURPOSE:To achieve high speed and high accuracy at the time of positioning for a certain aimed position by using estimated or measured disturbance force to an operational part so as to perform disturbance compensation, and by integrating the deflection between the output of an ideal model part and that of an operational condition detection part so as to carry out disturbance compensation, at the same time. CONSTITUTION:A driving command value of control valve group that drives and controls a pneumatic actuator is output by an operational control part 10 as well as by a disturbance compensation part 11. Positional deflection between the operational part and an aimed position, speed of the operational part by a differentiator 12, the deflection between reference pressure of an air chamber of the actuator and the measured pressures P1, P2, are input by amplifiers 13a, 13b of the operational control part 10, and a feedback control system in the condition of a pneumatic driving system is formed thereby. The disturbance compensation part 11 is composed of a forward disturbance compensator 21, an ideal response generation part 23, a deflection integrating part 22, a weighting part 19, and of a disturbance compensation command value adder 20, while the outputs of the amplifiers 13a, 13b are corrected. The positioning for a certain aimed position can be thus be performed at a high speed and with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a pneumatic drive device that operates using a compressed air source as a drive source.

Conventional technology pneumatic drive devices have a high output-to-weight ratio of the operating parts, so they can be easily made smaller and lighter. In addition, there is no need for a rotary transmission mechanism, which can easily and freely transmit power from the drive source to the operating parts using piping, which is also advantageous in reducing size and weight. Furthermore, pneumatic drive is inexpensive, does not pollute the environment, and has the advantages of retaining force and storing it as pressure energy. Due to factors such as the compressibility of air and the friction of the cylinder seal, it was difficult to position the system at any position using the pneumatic drive system. At present, positioning is only performed at one or a few points.However, control valves that have the function of changing the opening area of the valve part according to the command value have been advanced. In the following, an example of the conventional pneumatic drive device mentioned above will be explained with reference to the drawings.

Figure 4 is an overall view showing an example of a conventional pneumatic drive device. In Figure 4, 1 is a pneumatic swing type cylinder having an air chamber, 4 is compressed air @, and 5a and 5b are air inflows into the air chambers. A control valve that has a function of changing the opening area of the valve portion according to a command value in order to allow outflow; 6a and 6b are pressure sensors that detect the internal pressure of the air chamber, and 7 is a position sensor that detects the position of the operating portion. , Is 8 negative? E 9a
, 9b are controllers that drive the control valves 5a and 5b, respectively; 10 is an operation control section; and 21 is a forward disturbance force compensator.

FIG. 2 is a detailed explanatory diagram of the pneumatically driven oscillating cylinder in FIG. 4. 1 is a pneumatic swing type cylinder cylinder having an air chamber; 2 is a vane that can move inside the cylinder 1 while maintaining airtightness; 3a and 3b are air chambers divided by the vane 2; 4 is compressed air #5a and 5b are air chambers, respectively. 3a and 3b are control valves that have a function of changing the opening area of the valve portion according to a command value in order to allow air to flow out. 6a and 6b are pressure sensors that detect the internal pressure of the air chambers 3a and 3b, respectively. be.

FIG. 5 is a detailed explanatory diagram of the motion control section 10 and forward disturbance force compensator 21 in FIG. 4.

In FIG. 5, 12 is a differentiator, 13a and 13b are amplifiers, 14 is a disturbance force detection a, and 15 is a disturbance compensation force component. This is the feedback gain component of the pressure deviation from the reference pressure of 3a and 3b, and these are the oscillating cylinder 1, vane 2, load 8
This constitutes a state feedback control system for the pneumatic drive system, including:

The respective pressures in the air chambers 3a and 3b are pl, p2,
The moment of inertia of the vane 2 and the entire load is J, the viscous friction coefficient is b, the pressure receiving area of the vane is A, the center radius between the outer radius and the inner radius of the pressure receiving part of the vane is the rotational displacement amount of the first vane is θ
, if the disturbance force acting on the vane is d, then Jθ+bri+d=A-rO-(pi-p2)...
...(1) The following relationship holds true1 Here, θ is 2 related to the time of θ
The same-aircraft portion, θ represents one same-aircraft portion with respect to the time of θ. Pressure pi (i=1.2) and control valve opening area 5i (i=1
．． The relationship with 2) is as follows: Assuming that there is a sufficient difference between the upstream pressure and downstream pressure of the control valve, and performing linearization around the equilibrium point (reference pressure po), p1-kl・Sl・ps- becomes 2.・po・θ・・・・・・・・・(2) p2=kl・S2・ps2・pO・θ・・・・・・
...(3) The following relationship can be obtained. Here, ps is 1 for the supply pressure,
k2 is a constant related to the vane shape, temperature, etc. Here, the control human power U of the pneumatic drive device is applied to the vane with the input uf that performs state feedback control to compensate for the influence of air compressibility, etc. Input uh to compensate for the disturbance force
First, let's consider a system with the following equation without any disturbances, which constitutes a state feedback control system to compensate for the effects of air compressibility, etc.

J'j+bM=A-r(1(pl-p2)...
...(5) At this time, the state equation of this pneumatic drive device (Yo-A
c−x +Bc−u f ・・・・・・・・・
(6) x-[θ θ pi-po p2-pO]T. kT means a transposed matrix. When state feedback is performed based on modern control theory, the command value ufl becomes uf=-kc-e...
・(7) e −[θ −θ d δ pi
-pOp2-pO]T. However, θd is the target trajectory of the rotational displacement θ of the operating part, and kc is the state feedback gain matrix 13a, 13b.
It is possible to achieve positioning at any position of the moving part by suppressing the influence of air compressibility on the positioning operation through link control. Suppose that it is possible to estimate or measure by some means. (For example, a disturbance estimation observer) At this time, if the estimated value of the disturbance force is de, then the disturbance compensation human force u
For h, use the disturbance compensation gain kh obtained from the state feed pan-nk gain matrix kc, u h= −kh−d e −−−
(8), and from equations (4), (7), and (8), control human power U (y u = -kc-e-kh-de . .
......(9). Therefore, the influence of the compressibility of air can be compensated for by performing state feedback control of state quantities including pressure, and the influence of friction in the sealing part (such as
An input for canceling the friction is constructed from a value estimated or measured by a disturbance estimation observer, etc., and can be compensated by adding it to the control valve drive command value forward to each control valve.
It has become possible to position at any point at high speed (patent pending by the inventors) Problems to be solved by the invention (Patent pending by the inventors) By using the measured disturbance force and adding it forward to the command value to each control valve, it is possible to perform high-speed positioning at any point. Friction estimation delay and compensation delay In addition, control valve hysteresis and variation In view of the above problems, the present invention estimates or measures the disturbance force acting on the moving part, and estimates or measures the estimated or measured disturbance force. Compensating for the disturbance force using: and performing disturbance force compensation by integrating the deviation between the output value from the ideal model part of the pneumatic drive device in which no disturbance force acts on the operating part and the output value of the operating state detection part. This invention provides a pneumatic drive device that realizes operations such as positioning to arbitrary target positions at high speed and with high accuracy. The pneumatic drive device includes a pneumatic actuator that has an air chamber and an operating section that can move within the air chamber while maintaining airtightness, and a pneumatic actuator that inflows or injects air according to a command value into each of the air chamber groups divided by the operating section. a group of control valves capable of causing the air to flow out; a fluid force detection section that detects respective fluid forces applied to the operating section of the air chamber group; an operating state detection section that detects the operating state of the operating section; A disturbance force detection unit that estimates or measures the disturbance force applied to the operating unit, and a disturbance that constitutes a compensation force that cancels out the disturbance force using the output of the disturbance force detection unit. a forward disturbance force compensator having a compensation force component; and an ideal model section having a model of a pneumatic drive device in which the disturbance force does not act on the operating section; and inputting the target operating state to the ideal model section. an ideal response generation section that generates an ideal response of the operating section; a model deviation integrator that time-integrates the deviation between the output value of the ideal response generation section and the output value of the operating state detection section; and the model deviation integrator. a deviation integrating section having an integral gain multiplier that multiplies the output value by an integral gain; and a deviation integrating section having an integral gain multiplier that multiplies the output value by an integral gain, and multiplying the output value of the forward disturbance force compensator by a non-negative number m times the weight to give the output value of the deviation integrating section. n not a negative number
a disturbance force compensator having a weighting unit that multiplies a double weight, and a disturbance compensation command value adder that adds two output values of the weighting unit; the operating state detecting unit; and the fluid force detecting unit. A control valve drive command value necessary for the operating section to move according to the target operating state is given to the control valve group by inputting the output signal of the output signal, the target operating state, the fluid force reference value, and the output value of the disturbance force compensator. and an operation control section that outputs the output.

Operation The present invention uses the above-described configuration to compensate for the disturbance force using the estimated or measured disturbance force in the case where there is an influence of friction estimation delay, compensation delay, etc. By using external disturbance force compensation by integrating the deviation from the output value from a model of a pneumatic drive device in which no disturbance force is applied to the And it can be realized with high precision.

EXAMPLE Hereinafter, a pneumatic drive device according to an example of the present invention will be described with reference to the drawings.

FIG. 1 is an overall view showing the configuration of a pneumatic drive device in an embodiment of the present invention.

In Fig. 1, 1 is a pneumatic swing type cylinder having an air chamber, 4 is compressed air i5a, and 5b has a function of changing the opening area of the valve part according to a command value in order to allow air to flow into and out of the air chamber. Control valves, 6a and 6b are pressure sensors that detect the internal pressure of the air chamber, 7 is a position sensor that detects the position of the operating part, 8 is a negative i9a, 9
b is a controller that drives the control valves 5a and 5b, respectively; 10 is an operation control section; 11 is a disturbance force compensator; 19 is a weighting star; 20 is a disturbance compensation command value adder; 21 is a forward disturbance force compensator; 22 is a deviation integration section; 23 is a FIG. 2 is a detailed explanatory diagram of the pneumatically driven oscillating cylinder shown in FIG. 1. The pneumatically oscillating cylinder is the same as the conventional example.

FIG. 3 shows the first pneumatic drive device according to the embodiment of the present invention.
In FIG. 3, 12 is a differentiator, 13a and 13b are amplifiers, 14 is a disturbance force detection plate, and 15 is a disturbance compensation force component 16.
17 is an integrator 18 is an amplifier; 9 is a weighting unit; 20 is a disturbance compensation command value adder; 21 is a forward disturbance force compensator; 22 is a deviation integrator; and 23 is an ideal response generator.

13a and 13b are feedback gain components of the positional deviation of the operating part with respect to the target position, the speed of the operating part, and the pressure deviation of the air chambers 3a and 3b from the reference pressure, respectively;
These components constitute a state feedback control system for the pneumatic drive system including the pneumatic swing cylinder 1, vane 2, and load 8. The forward disturbance force compensator 21 (disturbance force detection unit 14 and disturbance compensation force configuration unit) 15, it has an ideal response generation section 23 (and an ideal model section 16 on which no disturbance force acts) and generates an ideal response of the operating section by inputting the target position to this ideal model section. 1
6, and an amplifier 18 that multiplies the output of the integrator 17 by an integral gain. The weighting section 19 multiplies the output value of the forward disturbance force compensator 21 by a non-negative weight of m times, multiplies the output value of the deviation integration section 22 by a non-negative weight of n times, and performs disturbance compensation. A command value adder 20 adds the two output values of this weighting section. The ideal model section 16 adds the input of equation (7) to the equation of state of the pneumatic drive device in which no disturbance force acts in equation (6), xm=Ac-xm+Bc-(-kc-e)=(Ac-
Bc-kc) -xm 10 Bc-kp・θd ・・・・・・・・・(1
0) k c-[k P k v k
It is expressed as prl k pr2koT. Here, xm is the state quantity of the ideal model.The state quantity θm related to the position of the state quantity xm of the ideal model is
The deviation between the state quantity θ regarding the position of the pneumatic drive device is integrated over time, the integral gain is multiplied by 1, and the output from the amplifier 18 is obtained as follows: Lui=ki−f (θm−θ) dt
---------------(i i) Then, the weighting section 19 ! i The output ui of the amplifier 18 expressed by Equation (11) is multiplied by a weight m, and the output uh of the disturbance compensation force configuration unit 15, which can quickly compensate for disturbance force expressed by Equation (8), is multiplied by a weight n. Then, the disturbance compensation command value adder 20 adds the values multiplied by the weights by the weighting section 19, and outputs the sum to the motion control section to compensate for the disturbance force acting on the motion section and perform positioning control. Here, as an example, we will explain the case where both weights are set to 1. At this time, the control valve drive command value u i, t, Equation (7)
, (8) and (11), u=-kc-e-kh-de +ki-f (θm-θ) dt ------...
−(12).

As described above, according to this embodiment, high-speed positioning is performed by quickly compensating for the disturbance force using the estimated or measured disturbance force (Ideal model part 1 where no disturbance force acts)
Integrating the positional deviation between the ideal response in step 6 and the response of the operating part L, friction estimation delay, compensation delay, and even the effects of control valve hysteresis and variation can be compensated for, achieving highly accurate positioning control. Therefore, when an arbitrary disturbance force acts on the operating portion, an operation such as positioning to an arbitrary target position can be easily realized at high speed and with high accuracy by using the external signal.

In this example, the force that deals with a system with one degree of freedom (a system with multiple degrees of freedom is also a threat). At that time, the disturbance d is not only the friction of the moving part, but also the interference force from other moving parts, and,
Coreoli 9 Centrifugal 9 It also includes those caused by inertial fluctuations and model errors.

In this example, the force (
The pneumatic drive device LL of the present invention can be similarly realized with a direct-acting cylinder, but the effects of the invention are greater than the effects of the invention. a group of control valves that can cause air to flow in or out according to a command value into each of the air chamber groups divided by the operating section; and a fluid force that detects the respective fluid force applied to the operating section of the air chamber group. a detection unit; an operation state detection unit that detects the operation state of the operation unit; a disturbance force detection unit that estimates or measures the disturbance force applied to the operation unit; and a disturbance force detection unit that estimates or measures the disturbance force applied to the operation unit. A model of a forward-facing disturbance force compensator having a disturbance compensating force component that configures a compensating force for canceling the disturbance force using the output of the disturbance force detecting section, and a pneumatic drive device in which the disturbance force does not act on the operating section. an ideal response generation section that inputs the target operating state into the ideal model section and generates an ideal response of the operating section; a deviation integrator including a model deviation integrator that time-integrates a deviation from an output value; and an integral gain multiplier that multiplies the output value of the model deviation integrator by an integral gain; and an output value of the forward disturbance force compensator. is multiplied by an m-fold weight that is not a negative number. A weighting unit that multiplies the output value of the deviation integration unit by a non-negative weight that is n-fold, and a disturbance compensation that adds the two output values of the weighting unit. A disturbance force compensator having a command value adder, output signals of the operating state detecting section and the fluid force detecting section, a target operating state, a fluid force reference value, and an output value of the disturbance force compensating section are input. an operation control section that outputs a control valve drive command value necessary for the operation section to move according to the target operation state to the control valve group; Friction is estimated by compensating for the disturbance force by integrating the positional deviation between the ideal response of the ideal model section on which no disturbance force acts and the response of the operating section. It has the effect of compensating for delays and compensation delays, as well as the effects of control valve hysteresis and variations, making it possible to realize high-speed and highly accurate positioning control of any operation of the pneumatic drive device.

[Brief explanation of drawings]

Fig. 1 is the entire pneumatic drive device according to the embodiment of the present invention @ Fig. 2 is a detailed view of the pneumatically driven oscillating cylinder in the pneumatic drive device of the same embodiment or a conventional example Fig. 3 is the operation of the pneumatic drive device Detailed view of the control unit and disturbance force compensator. Fig. 4 is a detailed view of the entire plate of the conventional pneumatic drive device. Fig. 5 is a detailed view of the operation control unit and the forward disturbance force compensator in the pneumatic drive device.

Claims (7)

[Claims] (1) A pneumatic actuator having an air chamber and an operating section that can move within the air chamber while maintaining airtightness; and a pneumatic actuator that allows air to flow in or out according to a command value into each of the air chamber groups divided by the operating section. a group of control valves capable of causing the air to flow out; a fluid force detection section that detects respective fluid forces applied to the operating section of the air chamber group; an operating state detection section that detects the operating state of the operating section; a disturbance force compensator that compensates for the disturbance force applied to the section; and the output signal of the operating state detector and the fluid force detector, the target operating state, the fluid force reference value, and the output value of the disturbance force compensator as inputs. an operation control section that outputs a control valve drive command value necessary for the operation section to move according to the target operation state to the control valve group, and the operation section is controlled by the resultant force of the fluid force acting on the operation section. A pneumatic drive device driven by:
A disturbance compensation force configuration in which the disturbance force compensation unit includes a disturbance force detection unit that estimates or measures the disturbance force applied to the operating unit, and a compensation force that uses an output of the disturbance force detection unit to cancel the disturbance force. a forward disturbance force compensator having a section;
an ideal model section having a model of a pneumatic drive device in which the disturbance force does not act on the operating section, and an ideal response generation section that inputs the target operating state to the ideal model section to generate an ideal response of the operating section; , a model deviation integrator that time-integrates the deviation between the output value of the ideal response generation unit and the output value of the operating state detection unit; and an integral gain multiplier that multiplies the output value of the model deviation integrator by an integral gain. a deviation integral part having
a weighting unit that multiplies the output value of the forward disturbance force compensator by a non-negative weight of m times, and multiplies the output value of the deviation integration unit by a non-negative weight of n times; 1. A pneumatic drive device comprising: a disturbance compensation command value adder that adds two output values. (2) The pneumatic drive device according to claim 1, wherein the weighting section changes the weight of the forward disturbance force compensator and the weight of the output value of the deviation integration section according to the operating state of the operating section. (3) The weighting section decreases the weight m of the forward disturbance force compensator and increases the weight n of the deviation integration section as the magnitude of the positional deviation between the target operating state and the operating state of the operating section becomes smaller. The pneumatic drive device according to claim 2, characterized in that: (4) The weighting section divides the magnitude of the positional deviation between the target operating state and the operating state of the operating section by the magnitude of the positional deviation between the initial state of the target operating state and the initial state of the operating state of the operating section. The calculated number is the weight m of the forward disturbance force compensator, and the weight n of the deviation integral part is 1 using the weight m of the forward disturbance force compensator.
3. The pneumatic drive device according to claim 2, wherein -m. (5) The pneumatic drive device according to claim 1, wherein the operation control section compensates for the disturbance force by changing the fluid force reference value using the output value of the disturbance force compensation section. (6) The fluid force detection section is composed of a pressure detection device group that detects the pressure of each of the air chamber groups, and the operation control section is composed of an operation state detection section, an output signal of the fluid force detection section, a target operating state, and a reference. 2. The pneumatic drive device according to claim 1, wherein a control valve drive command value necessary for movement according to the target operating state is output to the control valve group by inputting pressure and an output value of the disturbance force compensator. (7) The pneumatic drive device according to claim 1, wherein the operating state detection section is constituted by any one of means for detecting position, velocity, and acceleration, or a combination thereof.