JPH0539094A - Automatic autorotation landing control device for rotorcraft - Google Patents

Abstract

PURPOSE:To provide a landing control device with which a helicopter can be controlled automatically and safely from sinking to landing after the engine is stopped in flight of the helicopter and the helicopter is in its autorotation state. CONSTITUTION:An automatic autorotation landing control device 3 is provided with sensors 4 to detect flight condition such as an airframe posture, speed, altitude, when the helicopter is landing in autorotation condition target value, computing devices 5 to give target values of control from autorotation to landing, control computers 7 to generate control signals from the flight conditions and the target values and a target value changing data output device 6 to change control target values in order by the flight condition and a prescribed condition. At the time of generating the control signal from the flight condition and the target value, it is appropriate to use a fuzzy inference.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a helicopter flight control device which enables automatic landing by automatic rotation of a helicopter.

[0002]

2. Description of the Related Art In general, current helicopters are capable of being landed by autorotation in the event of engine failure during flight. However, landing by autorotation requires advanced maneuvering skills, especially when landing before flaring and touching down, it is impossible to redo, and there is a risk of crashing into the ground with a small error, Also, since there are many items that must be controlled, extremely high skill and experience are required for the operation. In this way, landing by autorotation puts a heavy burden on the pilot, but at present, all the operations depend on the pilot's skill.

The autorotation landing can be roughly divided into an autorotation entry part from the engine stop to a stable autorotation descent, and a part from the autorotation descent to flare and landing. .. Of these, autorotation entry allows a certain amount of time if it can prevent stall due to a sudden decrease in rotor speed that accompanies engine stop, and its operation does not require such rigor. Is relatively easy. For the actual automation of only the autorotation entry part, see, for example, JP-A-63-13899.
It has already been proposed by the publication. Regarding fixed-wing aircraft, Japanese Patent Laid-Open No. 2-296595 discloses
A technique for performing attitude control during flight of an aircraft by using fuzzy control is disclosed.

On the other hand, in the autorotation landing part of the helicopter, a small operation error leads to a collision with the ground, and it is necessary to keep the rotor rotational speed proper until just before touchdown. Further, at the time of touchdown, the aircraft attitude is appropriate. It is necessary to keep the descent rate and the forward speed almost zero while maintaining However, no proposal has been made to automate the landing part of the autorotation landing.

[0005]

Therefore, the present invention solves the above-mentioned problems in autorotation landing, performs automatic control input from autorotation descent to landing, and performs flare motion and landing operation immediately before landing. It is an object of the present invention to provide a control device capable of safely landing a helicopter in an autorotation state by automatically performing the operation.

Another object of the present invention is to provide a control device which can be operated by the pilot directly when the pilot requires it.

[0007]

In order to solve the above-mentioned problems, the automatic autorotation landing gear of the present invention has the following features:
Sensors for detecting flight conditions such as speed and altitude,
Means for giving a target value for control from autorotation descent to landing, means for generating a control signal from the flight state and the target value, and output data for changing the target value according to predetermined conditions And a control means for sequentially changing the target value of the control according to the flight condition and the predetermined condition.

When generating a control signal from the flight state and the target value, it is appropriate to use fuzzy reasoning or optimal control theory.

Further, it is desirable to allow manual control by the pilot by overriding the input of the control signal of the automatic autorotation landing control device described above.

[0010]

When the helicopter detects that the engine has stopped during normal flight, for example, when the torque has become less than a certain value, it is automatically switched to the descent and landing control by the automatic autorotation landing control device. The flight condition parameters for control are detected by the respective sensors, and calculated by the target value generating means by the detected value and the data output from the data output means for changing the target value according to a predetermined condition. Then, the control target value for each axis is sequentially changed and output. From the control target value and the flight state detected by the sensor, for example, fuzzy reasoning, the control signal for each axis is transmitted by the control signal generation means using the optimal control theory, etc., the helicopter is automatic autorotation descent by this control signal, Landing control is performed.

The condition for changing the target value should be one that takes into account the characteristics of the target airframe, reflects the pilot's operational know-how, and incorporates the condition for changing the target value obtained from experience. The most desirable value is entered in the computer beforehand. In addition, depending on the model, the optimum change conditions greatly change depending on the weight, altitude, temperature, etc., so in that case, it is possible to automatically change the change conditions accordingly.

Furthermore, by using fuzzy inference for control signal generation, the control gain changes non-linearly when a large operation is performed to quickly respond to a change in the target value and when the movement is stabilized near the target value. Come to do.

As described above, the control device of the present invention makes it possible for the helicopter to automatically and safely achieve a series of operations from autorotation descent to flare and landing.

[0014]

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of a flight control system of a helicopter incorporating an automatic autorotation landing control device according to the present invention, which is an example using fuzzy inference for a control computer. Note that, due to space limitations, FIG.
a, FIG. 1b.

With reference to FIG. 1, a description will be given below of how the control device is used to perform control from the automatic rotation descent to the landing.

When flying normally, pilot 1
The pilot steering signals δ _yp , δ _xp , δ _zp , and δ _cpp and the control signals δ _y , δ _x , δ _z , and δ _cp from the control unit are switched by the switching unit 2 as shown by the solid line in the figure. However, when the engine stop is detected (for example, when the torque Q becomes a certain value Q _o or less), the connection is switched as shown by a broken line in the figure, and the automatic autorotation landing control device 3 The steering is performed by the control signals δ _y , δ _x , δ _z , δ _cp . The automatic autorotation landing control device 3 includes a sensor group 4 for monitoring various parameters related to flight conditions for control, and a pitch axis and roll from autorotation to landing based on the parameters monitored by these sensors. A target value calculation device group 5 including target value calculation devices 51, 52, 53, 54 for calculating control target values for the axes, the yaw axis, and the CP axis, and the target value calculation devices 51-54. A target value change data output device 6 for outputting target value change data for sequentially changing the target value according to a predetermined condition according to altitude and descent rate to the target value calculation device for each axis; A control signal is generated from each parameter of the flight state monitored by the sensor 4 and each target value calculated by the target value calculation device group 5. Pitch axis for the roll axis, yaw axis, the control computer of the CP axis 71,7
The control computer group 7 is composed of 2, 73 and 74.

The control signal transmitted from the control device 3 or the pilot steering signal from the pilot 1 is input to each actuator of the actuator group 8 including the main rotor pitch direction actuator 81, the main rotor roll direction actuator 82 and the tail rotor actuator 83. Then, the rotor movement is controlled by controlling these rotors. The body movement status is displayed on the display device 10 in the cockpit.

The following numerical values are monitored as parameters for control by the automatic autorotation landing controller.

Θ: Pitch attitude angle V: Velocity Φ: Roll attitude angle V ′: Acceleration Ψ: Yaw attitude angle H: Altitude Q: Pitch rate H ′: Descent rate P: Roll rate N _r : Main rotor rotation speed R: Yaw rate N _r ′: Main rotor rotation speed change rate A pitch attitude sensor and a pitch rate sensor 41 are provided to detect the pitch attitude angle Θ and the pitch rate Q, respectively, and the speed V and the acceleration V ′ described above are provided. To detect the roll attitude angle Φ and the roll rate P, and a roll attitude sensor and roll rate sensor 43 to detect the roll attitude angle Φ and the roll rate P, respectively. A yaw attitude sensor and yaw rate sensor 44 to detect
An altitude sensor and a descent rate sensor 45 are provided to detect the altitude H and the descent rate H ′, and a rotor speed sensor 46 is provided to detect the main rotor rotational speed N _r and the rotational speed change rate N _r ′. There is.

The rate of change Q ', P', and R'from the pitch rate Q, roll rate P, and yaw rate R detected by the pitch rate sensor, roll rate sensor, and yaw rate sensor, respectively. Is required.

Further, the detected values of the altitude H and the descent rate H'by the altitude sensor and the descent rate sensor 45 are the target value calculation device (C
In addition to being input to the P-axis) 54, it is also input to the target value change data output device 6.

In the control of the pitch axis, the pitch attitude angle Θ obtained from the pitch attitude sensor, the pitch rate sensor, the speed sensor and the acceleration sensor, the pitch rate Q, the rate of change Q ', the speed V, the acceleration V'and the target. supplying data for target value changes to the pitch axis which is output by the value change data output device 6 to the target value computing unit (pitch axis) 51, calculates a target value Q _ref pitch rate, the value of Q _ref The error Q _err between the target value and the current value is _calculated from the values of and
The values of Q _err and Q are supplied to the pitch axis control computer 71. The control computer 71 performs fuzzy inference based on those values and the membership function stored in the fuzzy data storage device 71a to calculate the steering amount δ _y in the pitch axis direction. The signal of the calculated δ _y is supplied to the actuator 81 in the pitch direction of the main rotor, whereby the pitch axis is controlled and the speed is maintained or changed.
In addition, the posture angle is changed during flare.

The roll axis is the roll posture sensor, the roll posture angle Φ obtained from the roll rate sensor 43, the roll rate P, and its change rate P'and the target value change data output device 6 for changing the target value. data supplied to the target value computing unit (roll axis) 52 for, calculates a target value P _ref of the roll rate, the error P _err between the target value and the current value from the values of the P in P _ref Then, the P _err and P values are supplied to the roll axis control computer 72. Control computer 7
In step 2, fuzzy inference is performed by using those values and the membership function stored in the fuzzy data storage device 72a to calculate the steering amount δ _x in the roll axis direction. The calculated δ _x signal is supplied to the roll-direction actuator 82 of the main rotor, whereby the roll-axis direction control is performed, and it is possible to maintain an appropriate value of the roll attitude during autorotation landing.

The yaw axis is used for changing the target value output from the yaw attitude sensor, the yaw attitude angle Ψ obtained from the yaw rate sensor 44, the yaw rate R, and its rate of change R ′ and the target value change data output device 6. Is supplied to the target value calculation device (yaw axis) 53, and the target value R of the yaw rate is calculated.
_{The ref} is calculated, the error R _err between the target value and the current value is obtained from the R _ref value and the R value, and the R _err and R values are supplied to the yaw axis control computer 73. The control computer 73 performs fuzzy inference based on those values and the membership function stored in the fuzzy data storage device 73a to calculate the steering amount δ _z in the yaw axis direction. Calculated δ _z
Is supplied to the actuator 83 of the tail rotor, whereby the yaw axis direction is controlled, the yaw attitude during autorotation landing can be appropriately maintained, and unnecessary yaw generation can be suppressed.

The CP axis is composed of an altitude sensor, a descent sensor 45,
The altitude H, the descent rate H ′, the main rotor rotational speed N _r , the main rotor rotational speed change rate N _r ′ obtained from the rotor rotational speed sensor 46, and the target value change data output device 6 output the data. Data for changing the target value for the CP axis is supplied to the target value calculating device (CP axis) 54, and the target value N _{rref of the} rotor speed is set according to the condition for changing the target value _.
Alternatively, the target value H _ref ′ of the descent rate is calculated, and the calculated value,
The value of N _r or H'is supplied to the control computer 74 for the CP axis. The control computer 74 performs fuzzy inference based on those values, the fuzzy data, the membership function stored in the storage device 74a, etc., and calculates the operation amount δ _cp of the collective pitch lever. Calculated δ _cp
Is supplied to the actuators 81 and 82 in both the pitch direction and the roll direction of the main rotor, whereby the collective pitch is controlled, and the value of the rotor rotation speed is maintained within an appropriate range during autorotation landing. It is possible to change the descent rate.

As described above, in the present invention, the autorotation landing is controlled by using the following four control signals as outputs for the four axes of pitch, roll, yaw, and CP. Δ _y : Main rotor cyclic pitch (pitch direction) δ _x : 〃 (roll direction) δ _z : Tail rotor collective pitch δ _cp : Main rotor collective pitch This allows the helicopter to land safely by autorotation.

Next, the change of the target value will be described.

As described above, in the control of each of the pitch axis, roll axis, yaw axis, and CP axis, the target value is the data for changing the target value supplied from the target value change data output device 6 and each sensor. It is determined by the flight conditions supplied from the car and changes sequentially from the autorotation descent to the landing. An example thereof is shown in FIG.

This shows changes in the target of control in the pitch axis direction. First, during the steady autorotation descent, the speed V _{y at} which the descent rate is the minimum is the target. In this case, the pitch attitude angle is a means for achieving the velocity V _y. When starting flare just before landing, the speed is not the target, and the pitch attitude angle during flare itself is the target value. If the speed and descent rate have decreased sufficiently due to flare, the pitch attitude angle should be returned to be almost horizontal for landing (Θ
= 0) is the goal.

The above is an example of control in the pitch axis direction.
Other items are similarly changed depending on the conditions.

The target value change data output device is mainly used for altitude H
The final target value such as speed and descent rate and the timing of changing the value are monitored in 4
It is supplied to the axis target value calculation device. The pilot's operational know-how is reflected in the timing of this change.
In the target value calculation device, the values (Q _ref , P _ref , R _ref , H _ref , N _rref ) that are the target of actual control are based on them.
Is calculated.

Next, the control calculation in the control computer 7 will be described.

In the present invention, fuzzy inference is used for control calculation, and the fuzzy inference will be described with reference to FIG.

The fuzzy inference is composed of membership functions 101 and 102 indicating the magnitude of input / output and fuzzy rules 103 indicating the contents of control. The flight condition obtained by each sensor, the control error obtained from the target value, and the value of the flight condition are the membership function 1 of the antecedent part of the rule.
01 is compared, and the goodness of fit is calculated. The rule applied by the goodness of fit and the degree of its application are determined,
The fuzzy output is thereby determined, and the control signal is obtained by defuzzifying 104 that value.

When fuzzy reasoning is used for control, it is possible to easily perform non-linear control. This is because the control law consists of linguistic rules and the use of a membership function with a special shape as shown in FIG.

Further, since the control law is established by the linguistic rule, it is relatively easy to cope with the introduction of the pilot know-how in changing the target value.

Because of these characteristics, by utilizing fuzzy inference for control, it is possible to relatively easily realize control of complicated autorotation landing in which the target value changes successively.

However, the calculation of the control signal can be performed by a method other than the fuzzy inference, and can be realized by a method based on the optimal control theory, for example.

In the present invention, as described above, basically, the pitch attitude and velocity are controlled by δ _y , the roll attitude is controlled by δ _x , the yaw attitude is controlled by δ _z , and the descent rate and rotor speed are controlled by δ _cp . However, other methods such as detecting the sideslip angle with a sensor and controlling it by δ _x , or using δ _cp for controlling the pitch attitude angle are also variations of the present invention.

Further, in the present invention, in the switching section between the pilot steering signal and the control signal from the control device shown in FIG.
When steering is performed by the control device, the pilot inputs a value equal to or more than a value such as a stick or a pedal (δ _yp > δ _{yp 1} , δ _xp > δ _xp1 , δ _zp > δ
_zp1 or δ _cp > δ _cp1 ), the connection is switched (override), and control of the aircraft can be taken over from the automatic control device at any time.

[0042]

As described above, according to the present invention, the autorotation landing can be automatically performed by the method of successively changing the control target value according to the flight condition and the predetermined condition. Therefore, it is now possible to safely and reliably perform autorotation landing, which has been extremely dangerous until now, which was very dangerous, and greatly contributes to the overall safety of the helicopter. To do.

[Brief description of drawings]

FIG. 1a is a block diagram showing an embodiment of a flight control system of a helicopter adopting an automatic autorotation landing control device according to the present invention, in combination with FIG. 1b.

FIG. 1b is a block diagram showing an embodiment of a flight control system of a helicopter adopting the automatic autorotation landing control device according to the present invention, in combination with FIG. 1a.

FIG. 2 is a schematic diagram showing an example of sequentially changing a control target value according to a predetermined condition of the present invention.

FIG. 3 is an explanatory diagram of fuzzy inference applied to the present invention.

FIG. 4 is a schematic diagram showing an example of the shape of a membership relationship used for fuzzy inference applied to the present invention.

[Explanation of symbols]

1 pilot 2 switching unit 3 automatic rotation landing control device 4 sensor group 5 target value calculation device group 6 target value change data output device 7 control computer group 8 rotor actuator group 101, 102 membership relationship used for fuzzy reasoning

Claims (5)

[Claims] 1. An automatic autorotation landing control device for a rotary-wing aircraft that automatically flares and landes after the engine has stopped during flight and has entered autorotation before landing in an autorotation state. In addition, a sensor for detecting flight conditions such as the aircraft attitude, speed, and altitude, means for giving a target value for control from autorotation descent to landing, and a control signal from the flight condition and target value. Means to generate,
And a means for outputting data for changing a target value according to a predetermined condition, characterized in that the target value of the control is sequentially changed according to a predetermined condition by the flight state and the data. Device to do. 2. The apparatus according to claim 1, wherein fuzzy reasoning is used in generating a control signal from the flight condition and a target value. 3. The apparatus according to claim 1, wherein an optimal control theory is used in generating a control signal from the flight condition and a target value. 4. The apparatus according to claim 1, wherein the condition for changing the target value is automatically changed to an optimum one according to the body weight, the flight altitude, the temperature, and the like. 5. The apparatus according to claim 1, wherein the pilot can be manually controlled by overriding the input of the control signal.