JPH0411440B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides a gust load reduction control system that reduces the load caused by the gust by detecting the gust acting on an aircraft and automatically performing compensatory steering in response to the gust. In particular, the present invention relates to a gust load reduction control system for aircraft that can reduce loads in response to both standing gusts and continuous gusts.

BACKGROUND ART Conventional gust load reduction control systems for aircraft include an open-loop control system as shown in FIG. 5 and a closed-loop control system as shown in FIG. 6. First, the open loop control method uses the fifth
As shown in the figure, when the aircraft 1 encounters a gust, there is a gust response unit 3 that detects the gust component and operates control surfaces such as ailerons and elevators using an actuator 2; The damper section 4 damps the vertical movement of the aircraft body 1 caused by the wind gust, and these operations reduce the load caused by the gust of wind. Here, the gust response section 3 includes a first sensor 5, such as an angle of attack meter, which is installed in the nose of the aircraft and detects the vertical component of the gust, and a sensor 5 that cuts out the extremely low frequency region or the extremely high frequency region of the gust component. Aircraft 1 with washout filter 6 and steering to cope with gusts.
a prefilter 7 that corrects the characteristics to increase stability so that they do not become unstable; and a first gain that determines how many times the value corrected by the prefilter 7 is to be given to the actuator 2 as a control value. It consists of a setting device 8. The damper section 4 also includes a second sensor 9, such as an accelerometer, which is installed in the center of the fuselage and detects the motion of the entire aircraft, and the actuator 2, which multiplies the detection amount of the second sensor 9. It consists of a second gain setter 10 that determines whether to give it as a control value. The first sensor 5 detects the relevant gust component at the nose of the aircraft before the gust reaches the main wing, and the control surface is steered before the gust reaches the main wing and shakes the aircraft 1. The gust load is reduced by determining the amount of gust and steering the aircraft 1 in synchronization with the phase of the oscillation caused by the actual gust to suppress the oscillation.

Next, the closed loop control method described above is applied to the sixth
As shown in the figure, a first sensor 11, a first gain setting device 12, and a control surface for controlling ailerons, elevators, etc., detect movements caused by gusts on the aircraft body 1, main wings, etc. and a gust corresponding part 13 operated by the actuator 2, and these operations reduce the load caused by the gust of wind. Here, the gust response section 13 includes a second sensor 14 such as an accelerometer that is installed in the center of the fuselage and the tip of the main wing and detects the aircraft movement of the entire aircraft;
A compensator 15 that matches the phase of the gust and the phase of the control surface by steering corresponding to the gust as much as possible so that the characteristics of Second gain setter 16 that determines whether to give it as a control value
It consists of The first sensor 11 is an angle of attack meter installed in the nose of the aircraft, and the first gain setter 12 multiplies the detection amount of the first sensor 11 and sends it to the actuator 2 as a control value. The first sensor 11 and the first gain setter 12 determine whether the gust corresponding part 1
This serves as a damper section that dampens the vertical movement of the aircraft 1 due to the steering operation in step 3. Then, the second sensor 14 detects that the gust of wind has reached the main wing, causing a change in the lift of the main wing, which causes the aircraft 1 to vibrate, and also determines the amount of steering of the control surface to suppress the vibration. It was designed to reduce the gust load by steering the aircraft in a restraining manner.

Problems to be Solved by the Invention However, in the open-loop control system described above, the first sensor 5 such as an angle of attack meter installed in the nose of the aircraft quickly detects the vertical component of the gust, and the load caused by the gust is Since the control surface is steered to reduce It was small. In addition, in the closed-loop control system described above, second sensors 14 such as accelerometers installed at the tips of the main wings and in the center of the fuselage detect the movements of the entire aircraft caused by gusts of wind. Since the control surface is steered in a pressing manner,
The load reduction effect was large for continuous gusts containing a wide range of frequency components, but the load reduction effect was small for impactful arcing gusts.
Furthermore, there are some models that have both the open-loop control method and closed-loop control method mentioned above.
Each of these control systems is independent, and gust load reduction is mainly performed using an open-loop control system.
The closed-loop control scheme was only used as a damper of the high frequency adverse effects caused by the open-loop control. Therefore, the open-loop control system and the closed-loop control system cannot perform optimal control for both standing gusts and continuous gusts. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a gust load reduction control system for an aircraft that can reduce the load in response to standing gusts and continuous gusts with a single control system.

Means for Solving the Problems The means of the present invention for solving the above problems is to detect the vertical component of a gust using a gust sensor installed in the nose of the aircraft, and reduce the load caused by the gust by controlling the control surface. It has an open loop control section and
It has a closed-loop control unit that detects aircraft movement using whole-aircraft motion sensors installed in the center of the fuselage and the tips of the main wings, and suppresses elastic vibrations of the aircraft using control surface steering.
The aircraft is controlled by adding the steering amount control value generated from the detection signal of the gust sensor in the open loop control section and the steering amount control value generated from the detection signal of the whole aircraft motion sensor in the closed loop control section. This is achieved by configuring an optimal control system that operates the actuator that steers the control surface to reduce the gust load acting on the aircraft body.

Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the accompanying drawings.

FIG. 1 is a block diagram showing an embodiment of the gust load reduction control method for an aircraft according to the present invention. This gust load reduction control system reduces the load caused by the gust by detecting the gust acting on the aircraft and automatically performing compensatory steering accordingly. The actuator 2 has an actuator 2 that operates a control surface such as an aileron or an elevator provided on the turret, an open-loop control section 20, and a closed-loop control section 21.

The open loop control unit 20 mainly reduces the load caused by the gust component by controlling the control surface.
A gust sensor 22 (see Figure 2) such as an angle of attack meter installed in the nose of the aircraft body 1 to detect the vertical component of gust wind, and a washout that cuts out the extremely low frequency range or extremely high frequency range of the gust component. Filter 23
, a prefilter 24 that corrects the characteristics of the aircraft 1 to the side that increases stability so that it does not become unstable due to steering in response to gusts, and this prefilter 24
and a first gain setter 25 for setting a gain constant to determine how many times the corrected value is to be given to the actuator 2 as a control value.

The closed-loop control unit 21 is mainly used to suppress elastic vibrations of the aircraft 1 due to aircraft motion by control surface steering, and is provided at the center of the fuselage and the wing tips of the aircraft 1 to detect acceleration of the entire aircraft. All-machine motion sensors 26 (see Figure 2) such as gauges and pitch rate gauges (provided only on the fuselage);
A compensator 27 that matches the phase of the gust as much as possible with the phase of the control surface by steering corresponding to the gust so that the characteristics of the aircraft 1 do not become unstable, and this compensator 27
and a second gain setter 28 for setting a gain constant that determines how many times the value given by is to be given to the actuator 2 as a control value.

The control value of the steering amount generated from the detection signal of the gust sensor 22 of the open loop control section 20 and the control value of the steering amount generated from the detection signal of the whole machine motion sensor 26 of the closed loop control section 21. An optimal control system is constructed in which the actuator 2 that steers the control surface of the aircraft body 1 is actuated by adding them together at the addition point A.

FIG. 2 is an explanatory diagram showing an outline of an aircraft to which the gust load reduction control method of the present invention is applied. The above-mentioned gust sensor 22 is provided with its vanes exposed to the airflow on both sides of the nose portion. Also,
The whole aircraft motion sensor 26 includes an accelerometer 26a provided at the wing tip of the main wing, an accelerometer and pitch rate meter 26b provided at the center of the fuselage, and the like. Furthermore, actuators 2a, 2a are provided within the main wing tips to operate the outboard ailerons 29, 29, which serve as control surfaces for main wing motion, and within the horizontal stabilizer, elevators are provided as control surfaces for overall aircraft motion. Actuators 2b, 2b for actuating the actuators 30, 30 are provided. Further, a control computer 31 is provided at the front of the fuselage of the aircraft 1, and a part of this control computer 31 includes a washout filter 23, a prefilter 24, and first and second gain setting devices 2.
5, 28, a compensator 27, etc. are incorporated. The control computer 31, the gust sensor 22, the whole machine motion sensors 26a, 26b, and each actuator 2a, 2b are connected to a data bus 32.
By transferring data through this connection, the control computer 31 controls the operation of each element shown in FIG.

Next, the operation of such a gust load reduction control system will be explained. First, when the aircraft encounters a gust of wind, the gust sensors 22, 22 of the open loop control unit 20 detect the vertical component of the gust before it reaches the main wing W. The detection signals output from the gust sensors 22, 22 are input to a washout filter 23, where extremely low frequency ranges or extremely high frequency ranges are cut out. Next, the output signal of the washout filter 23 is input to the prefilter 24, and the open-loop control unit 20 performs steering to accommodate the gusts of wind to correct the characteristics of the aircraft 1 to the side that increases its stability so that the characteristics do not become unstable. be done. Thereafter, the output signal of the prefilter 24 is input to the first gain setter 25 and multiplied by the gain constant at an appropriate ratio to generate a control value for the open loop control section 20 for the actuator 2. In this way, before the gust reaches the main wing W and shakes the aircraft 1, the open loop control unit 20 determines the amount of steering of the control surfaces such as the outer aileron 29 and the elevator 30. .
Then, the control value of this steering amount is set to the actuator 2.
By inputting, the aircraft 1 due to the actual gust
The outer aileron 29 or elevator 30 shown in FIG.
to steer. At the same time, the whole aircraft motion sensor 26 of the closed loop control unit 21 detects that a gust of wind acts on the main wing W, causing a change in lift of the main wing W, which causes the aircraft 1 to vibrate. Then, the detection signal output from the whole aircraft motion sensor 26 is input to the compensator 27, and the phase of the gust is matched as much as possible with the phase of the control surface by the closed-loop control unit 21's steering corresponding to the gust, thereby improving stability. It is corrected to the side that increases. Next, the output signal of the compensator 27 is input to the second gain setter 28 and multiplied by the gain constant at an appropriate ratio to generate a control value for the closed loop control section 21 for the actuator 2. In this way, at the same time that the fuselage 1 is vibrated by the gust of wind, the closed loop control section 21 determines the amount of steering of the control surfaces such as the outboard aileron 29 and the elevator 30. Then, by inputting the control value of this steering amount to the actuator 2, the outer aileron 29 or the elevator 30 shown in FIG. 2 is steered so as to suppress the shaking of the aircraft 1 due to gusts. for example,
If there is an upward gust of wind, the outboard ailerons 29
Steering the trailing edge downward to reduce lift. Also,
When the pitching motion of the aircraft 1 is excited by a gust of wind, the elevator 30 is
When pitching with the head raised, the elevator 30 is steered to lower the trailing edge. Through such an operation, the open loop control unit 20 controls the gust sensor 22 such as an angle of attack meter installed in the nose of the aircraft to quickly detect the vertical component of the gust and reduce the load caused by the gust. Since the control surface is used for steering, the load can be reduced in the case of shocking gusts of wind. In addition, mainly in the closed-loop control unit 21, whole-plane motion sensors 26 such as accelerometers installed in the center of the fuselage and the tips of the main wings detect the motion of the whole plane caused by gusts of wind and calculate the motion. Since the control surface is steered to suppress the load, the load can be reduced against continuous gusts containing a wide range of frequency components.

Although FIG. 2 shows the outer aileron 29 and the elevator 30 as control surfaces, the present invention is not limited thereto, and the inner aileron 33, 33 may be used in combination.

Figures 3 and 4 are graphs showing the results of mathematical simulations performed using the aileron effectiveness determined by the quasi-steady lift surface theory, and each expresses the load due to gusts in terms of the bending moment at the root of the main wing. First, Fig. 3 is a graph showing the load response time history to a standing gust, and shows that the conventional closed-loop control method shown by the dashed line b has a load reduction effect compared to the case without control surface control shown by the broken line a. In contrast, it can be seen that the gust load reduction control method of the present invention shown by the solid line c significantly improves the load reduction effect. Next, Fig. 4 is a graph showing the load power spectrum for continuous gusts, and shows that the conventional open-loop control method shown by the dashed line e has less load reduction effect than the case without control surface control shown by the broken line d. In contrast, it can be seen that the gust load reduction control method of the present invention shown by the solid line f significantly improves the load reduction effect.

Effects of the Invention As described above, the present invention is based on the control value of the steering amount generated from the detection signal of the gust sensor 22 of the open loop control section 20 and the detection signal of the whole machine motion sensor 26 of the closed loop control section 21. An optimal control system is constructed that operates the actuator 2 that steers the control surface of the aircraft 1 by adding the control value of the generated steering amount. It is possible to reduce the gust load due to continuous gust wind including a wide range of frequency components mainly by the closed loop control unit 21. Therefore, according to the present invention, a single control system can exhibit the effect of reducing the load against standing gusts and continuous gusts. In addition, the open loop control section 20 and the closed loop control section 21
do not operate independently,
They are added at addition point A in the control system,
Optimization control can be performed for both standing gusts and continuous gusts. Due to these factors, the structure of the aircraft can be made lighter, and the comfort of the aircraft can also be improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the gust load reduction control method for an aircraft according to the present invention, FIG. 2 is an explanatory diagram showing an overview of an aircraft to which the gust load reduction control method of the present invention is applied, and FIG. Figure 4 is a graph of numerical simulation results showing the load response time history for standing gusts, Figure 4 is a graph of numerical simulation results showing the load power spectrum for continuous gusts, Figure 5 is a block diagram showing the conventional open loop control method. FIG. 6 is a block diagram showing a conventional closed loop control system. 1... Airframe, 2, 2a, 2b... Actuator, 20... Open loop control section, 21... Closed loop control section, 22... Gust sensor,
23...washout filter, 24...prefilter, 25...first gain setting device, 26,
26a, 26b... Whole aircraft motion sensor, 27... Compensator, 28... Second gain setter, 29... Outer aileron, 30... Elevator, 33... Inner aileron, W... ...Main wing.

Claims (1)

[Claims] 1. It has an open-loop control unit that detects the vertical component of gusts using a gust sensor installed in the nose of the aircraft and reduces the load caused by the gust using control surface steering. It has a closed-loop control unit that detects the aircraft movement using a motion sensor and suppresses the elastic vibration of the aircraft using control surface steering, and the control value of the steering amount generated from the detection signal of the gust sensor of the open-loop control unit and the closed-loop control unit. By configuring one optimal control system that adds the control value of the steering amount generated from the detection signal of the whole aircraft motion sensor in the control unit and operates the actuator that steers the control surface of the aircraft, it is possible to An aircraft gust load reduction control method characterized by reducing gust load.