JPH08193799A - Airframe controller - Google Patents

Abstract

PURPOSE: To realize an apparatus which can avoid the decrease in response or spatially stable performance at a low speed and high altitude of an airframe. CONSTITUTION: This airframe controller comprises a proportional control unit 1 and an integrating control unit 2 for inputting the deviation (e) of an acceleration command nC and an airframe acceleration (n), and a changeover switch 9 inputting the output signals of the units 1, 2 to switch and output an output signal according to whether the deviation (e) falls within the range of a predetermined allowable value ε or not, wherein since the designing of the units 1, 2 can be independently conducted, the performance of the control system can be raised to its limit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a body control device incorporated in an autopilot of a flying body.

[0002]

2. Description of the Related Art As shown in FIG. 4, a conventional airframe control device for a flying vehicle comprises a proportional controller 01 and an integral controller 02.
And the adder 03.

In the above, each controller 01, 0
2, the acceleration command n _C is subtracted from the body acceleration n detected by the acceleration sensor by the subtractor 05 and input, and the output signals of the controllers 01 and 02 are added by the adder 0.
4 is added, and the added output signal is output by the machine control device 03 to control the machine. The gains (coefficients) k _A and k _B of the controllers 01 and 02 are the flying objects. It was scheduled according to the altitude and speed of.

[0004]

In the conventional apparatus, the control performance is the performance at the nominal point (altitude, speed) when designing the controller even when scheduling the gain of the controller at the altitude or speed of the airframe. There is the following problem because it largely depends on.

That is, (1) the response decreases at low speed and high altitude. That is, the time constant becomes large. (2) Spatial stability performance (airframe motion characteristics) with respect to the seeker deteriorates.

Although such deterioration in performance is usually dealt with by increasing the gain of the controller, there is a limit because increasing the gain lowers the stability margin of the control system.
Further, the flying environment of the flying object (altitude, speed, etc.) is wide, and it has been difficult to optimize the control performance in all areas.

Therefore, the gain setting value of the controller must be a conservative value, and the above-mentioned problem cannot be avoided. The present invention is intended to solve the above problems.

[0008]

A body control device of the present invention inputs a proportional controller and an integral controller for inputting a deviation between an acceleration command and a body acceleration, and output signals of the respective controllers. Input the above deviation and output the output signal of the integral type controller when the deviation is within the range of the predetermined allowable value, and output the output signal of the proportional type controller when it is out of the range to control the aircraft. It is characterized by having a changeover switch for performing.

[0009]

In the above, the proportional controller has a function of controlling the speed at which the body acceleration follows the acceleration command, and the quick response of the control system can be improved by increasing the gain of this controller. .

Further, the integral type controller has a function of controlling the accuracy of following the acceleration of the body to the acceleration command, and the steady characteristic of the control system can be improved by increasing the gain of this controller.

Each of the controllers, to which the deviation between the acceleration command and the body acceleration is input, performs a predetermined calculation,
Each output signal is input to the changeover switch, and the changeover switch outputs the output signal of the integral type controller when the deviation is within the range of the predetermined allowable value, and outputs the output signal of the proportional type controller when it is out of the range. The output signal is output to control the machine.

Therefore, highly accurate control is possible when the above deviation is within a predetermined permissible value range, and highly responsive control is possible when the above deviation is outside the range, and system movement such as that of a flying object is possible. Even if the characteristics greatly change depending on the flight environment (altitude, speed), these influences on the control performance can be reduced.

Since the proportional controller and the integral controller are independent, the gain of each controller can be set higher than that of the conventional controller (proportional + integral controller). It is possible to improve the control performance in controlling the flying body or the like.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An airframe controller according to an embodiment of the present invention will be described with reference to FIG. In addition, this embodiment is applied to a flying object.

The apparatus of this embodiment shown in FIG. 1 has an acceleration command n _C (n _C = n _{C in} the case of proportional navigation) obtained by guidance calculation.
N'σ, N '; inductive gain, σ; inductive signal) and the vehicle body acceleration n obtained by the acceleration sensor 6 of the inertial device are input and the deviation e is output from the subtracter 5 which is the proportional type. The controller 1, the integral controller 2, the absolute value calculator 7, the subtracter 8 that inputs the absolute value | e | output from the absolute value calculator 7 and subtracts the allowable value ε, and each of the above controllers A changeover switch 9 for controlling the machine body is provided by inputting the output signals of 1 and 2 and the subtractor 8 and outputting a control signal.

In the above description, the proportional controller 1 determines the follow-up speed (rapid response) of the body acceleration n to the acceleration command n _C , and the quick response of the system is increased by increasing the gain k _A. be able to.

The integral type controller 2 determines the accuracy (steady characteristic) of the acceleration n following the acceleration command n _C , and the steady characteristic can be improved by increasing the gain k _B.

Each of the controllers 1 and 2 receives the deviation between the acceleration command n _C and the machine body acceleration n, performs a predetermined calculation, and inputs the respective output signals to the changeover switch 9.

Further, the acceleration command n _C and the body acceleration n
Deviation e of is also input to the absolute value calculator 7 and its absolute value |
After e | is obtained, the allowable value ε preset by the designer is subtracted from this absolute value | e |, and the subtracted value is input to the changeover switch 9.

The change-over switch 9 switches its output depending on whether the subtracted value is positive or negative.
When |-[epsilon]> 0 (e <-[epsilon], e> [epsilon]), the output signal of the proportional controller 1 is output with the changeover switch 9 on the 1 side, and | e |-[epsilon] ≤0 (-[epsilon] ≤e When ≦ ε), the changeover switch 9 is set to the 0 side and the output signal of the integral type controller 2 is output.

FIG. 2 shows the state of the changeover of the changeover switch 9 and the response of the acceleration when the machine body control is actually performed by using the apparatus 3 according to the present embodiment. The contents will be described below. The acceleration command n _C is a step function here.

In FIG. 2, first, at the start of control, the rising of the acceleration n is accelerated by proportional control, and at the subsequent transient response, the control deviation (e = n _C -n) is reduced while finely switching between proportional control and integral control. Control. Then, finally, integral control is performed so that the control deviation e becomes 0 as a steady characteristic.

The difference from the conventional controller (proportional + integral control) shown in FIG. 4 is that the conventional controller has a single control structure, whereas the embodiment shown in FIG. The control device 3 of 1 has a structure having two independent controllers 1 and 2.

Therefore, even in the design stage, the gains (coefficients) of the two controllers can be designed independently of each other, and the individual gains can be raised to their limits. Since the conventional control device cannot individually set the gains in this way, the gain distribution is conservative.

The above will be specifically described below by using a machine model represented by the following equation. [1 / (1 + τs)] · [ω ² / (s ² + 2ζωs + ω ² )] where τ is a time constant, ζ is a damping rate, ω is a natural frequency, and s
Is the Laplace operator.

Here, as a typical value, τ = 0.
2, ω = 55 Hz and ζ = 0.2 were used. Further, as the constants of the controllers 1 and 2, the proportional gain k _A = 10 and the integral gain k _B = 500 were used.

FIG. 3 shows the response of the acceleration n when the conventional type control (FIG. 4) and the variable structure control according to the present embodiment (FIG. 1) are performed on the above machine body model. As can be seen from FIG. 3, even if the conventional control becomes unstable, the variable structure control can stabilize the control.

This is because the gain distribution (k _A
= 10, k _B = 500) is too high. In the case of variable structure control, since the controller is switched according to the control situation, the individual gain can be set higher than in the conventional control, and thus the control performance can be improved.

[0029]

The airframe controller of the present invention inputs the output signals of the proportional type controller and the integral type controller for inputting the deviation between the acceleration command and the airframe acceleration, and the output signals of the respective controllers, and the deviation is set to a predetermined value. Since the controller can be designed independently by providing the changeover switch that switches and outputs the above output signal depending on whether it is within the range of the allowable value, the performance of the control system can be raised to the limit. It will be possible.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a body control device for a flying vehicle according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of an operation and an acceleration response of the changeover switch according to the embodiment.

FIG. 3 is a comparison diagram of a response between the above-described embodiment and a conventional control.

FIG. 4 is an explanatory diagram of a conventional device.

[Explanation of symbols]

 1 Proportional controller 2 Integral controller 3 Airframe controller 5 Subtractor 6 Accelerometer 7 Absolute value calculator 8 Subtractor 9 Changeover switch

Claims (1)

[Claims] 1. A proportional type controller and an integral type controller for inputting an acceleration command and a deviation of an airframe acceleration, and an output signal of the respective controllers, and the deviation is inputted and the deviation is a predetermined allowance. A fuselage characterized by including a changeover switch for controlling the fuselage by outputting the output signal of the integral controller when the value is within the range and by outputting the output signal of the proportional controller when the value is out of the range Control device.