JP2005247009A - Control device for unmanned helicopter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device for an unmanned helicopter capable of performing the stable turning flight even when the helicopter is under strong wind or the weight of a helicopter body 3 is large while employing the configuration to facilitate the steering operation. <P>SOLUTION: A maximum turn bank angle setting means 23 is provided, which obtains the maximum turning bank angle allowing the stable flight in the present flight condition of the helicopter body 3. A turn yaw rate correction means 24 is provided, which set the turn yaw rate of the helicopter body 3 so that the actual turn bank angle is not larger than the maximum bank angle when the actual bank angle of the helicopter body 3 is larger than the maximum turn bank angle. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a control device for an unmanned helicopter that controls the flight of an unmanned helicopter that sprays agricultural chemicals or performs aerial photography of a dangerous area, for example.

  As a conventional control device for an unmanned helicopter of this type, for example, there is one disclosed in Patent Document 1. The unmanned helicopter shown in this publication flies using an engine as a power source, and detects various attitudes of servo motors for opening and closing the throttle valve and changing the state of the main rotor and tail rotor, and the attitude of the fuselage. A posture sensor, a speed sensor that detects the speed of the aircraft, a communication device that performs wireless communication with the ground control device, and the like are mounted.

The control device that controls the flight of the unmanned helicopter is configured to control the operation of each servo motor of the aircraft so that the aircraft flies along a target flight course. For example, when turning the airframe, the control device uses a bank angle (hereinafter referred to as the bank angle) from the flight speed of the airframe detected by the speed sensor and the turning yaw rate (turning angular velocity) corresponding to the target flight course to the turning center direction. The angle is referred to as a turning bank angle), and the aircraft can be tilted so that the tilt angle of the aircraft matches the turning bank angle.
In addition, the applicant could not find any prior art documents closely related to the present invention by the time of filing other than the prior art documents specified by the prior art document information described in the present specification. .
Japanese Patent Laid-Open No. 2001-80586 (5th page, FIG. 1)

  In the conventional unmanned helicopter control device configured as described above, it may be difficult to keep the altitude of the airframe constant during a turn flight depending on the flight conditions. This is because the conventional control device determines the turning bank angle of the aircraft at the time of turning from the flight speed of the aircraft and the turning yaw rate. In other words, unmanned helicopters may have an excessively large turning bank angle without being operated due to wind hitting the aircraft during turning. In such a case, the conventional control device can handle this. However, the aircraft's lift is insufficient and the altitude is lowered. Such a phenomenon of insufficient lift occurs similarly even when the wind is weak and the weight of the cargo loaded on the aircraft is large. In order to eliminate such problems, it is necessary to avoid complicated operation.

  The present invention has been made to solve such problems, and aims to enable a stable turning flight even under strong winds or when the weight of the aircraft is large, while adopting a configuration that facilitates maneuvering operations. To do.

  In order to achieve this object, the unmanned helicopter control device according to the present invention is an unmanned helicopter control device that sets the turning bank angle of the aircraft according to the flight speed and the turning yaw rate. The maximum turning bank angle setting means for obtaining the maximum possible turning bank angle, and the actual turning angle of the aircraft detected by the aircraft bank angle detection sensor is greater than the maximum turning bank angle. And a turning yaw rate correcting means for setting the actual turning bank angle to be equal to or smaller than the maximum turning bank angle.

  The unmanned helicopter control device according to the second aspect of the present invention is the unmanned helicopter control device according to the first aspect of the present invention, wherein the maximum turning bank angle setting means is configured such that the thrust of the fuselage is determined from the throttle valve opening of the engine. And a correction means for correcting the maximum turning bank angle corresponding to this thrust.

  The control device for an unmanned helicopter according to the present invention automatically sets the turning yaw rate so that the actual turning bank angle of the aircraft does not exceed the maximum turning bank angle during turning flight. Therefore, according to this control device, it is possible to always perform a stable turning flight without being affected by wind in the flying area, the weight of the aircraft, etc. without causing the aircraft operator to perform complicated calculations or complicated operations. Can do. In particular, as in the unmanned helicopter control device according to the present invention, it is possible to reduce the change in the flight speed during the turn by reducing the turning bank angle by changing the turning yaw rate. The behavior can be further stabilized.

Since the opening degree of the throttle valve of the unmanned helicopter varies depending on the flight speed, the weight of the fuselage, the temperature, and the like, the flight condition of the unmanned helicopter can be indirectly detected based on the opening degree of the throttle valve. Therefore, according to the second aspect of the present invention, the flight condition (temperature, aircraft weight, flight speed) is determined by utilizing the opening of the throttle valve that changes according to the temperature in the flight area, the weight of the aircraft, the flight speed, and the like. The maximum turning bank angle can be determined according to
Therefore, according to the present invention, the airframe can be turned at an appropriate turning bank angle adapted to the flight conditions, so that the stability during turning can be further improved.

Hereinafter, an embodiment of an unmanned helicopter control device according to the present invention will be described in detail with reference to FIGS.
1 is a block diagram of an unmanned helicopter control device according to the present invention, FIG. 2 is a block diagram of the unmanned helicopter control device according to the present invention, and FIG. 3 is a diagram for explaining a control method during a turning flight, FIG. Is a graph that becomes a map for obtaining the maximum turning bank angle corresponding to the flight speed, and FIG. 5 is a flowchart for explaining the operation of the unmanned helicopter control device according to the present invention.

  In these drawings, what is indicated by reference numeral 1 is an unmanned helicopter whose flight is controlled by the control device 2 (see FIG. 2) according to this embodiment. This unmanned helicopter 1 flies using an engine (not shown) as a power source, for example, sprays agricultural chemicals or performs aerial photography of dangerous areas. In FIG. 1, 3 indicates an airframe of the unmanned helicopter 1, 4 indicates an attitude sensor for detecting the attitude of the airframe 3, 5 indicates an airframe side communication device, and 6 indicates a radio control device. As is well known in the art, the wireless control device 6 and the aircraft-side communication device 5 use various data for controlling the aircraft (position data, altitude data, velocity data, attitude data, flight direction data) through wireless communication. Etc.).

  The control device 2 according to this embodiment includes servo motors 8 to 12 of the airframe 3 so that the airframe 3 flies along the target flight course set by the input device 7 of the radio control device 6 (see FIG. 2). As shown in FIG. 2, the attitude sensor 4, the speed sensor 13 for detecting the flight speed of the airframe 3, the position sensor 14 for detecting the position of the airframe 3, and the heading The azimuth sensor 15 for detecting, the throttle valve opening sensor 16 for detecting the opening of the throttle valve of the engine, the input device 7 and the CPU 21 provided in the radio control device 6, and the airframe 3 are mounted. The servo motors 8 to 12 are configured.

The servo motors on the machine body 3 side are an elevator servo motor 8, an aileron servo motor 9, a collective servo motor 10, a ladder servo motor 11, and a throttle valve servo motor 12.
The engine and sensors mounted on the airframe 3 are equivalent to those mounted on a conventional unmanned helicopter. In order to detect the flight speed of the airframe 3 or to detect the airframe position, although not shown, it can also be implemented using a GPS sensor mounted on the airframe.

The CPU 21 includes a flight control means 22, a maximum turning bank angle setting means 23, a turning yaw rate correction means 24, and the like which will be described later.
The flight control unit 22 performs feedback control to control each servo so that the target flight state input by the input device 7 of the radio control device 6 matches the actual flight state detected by each sensor of the airframe 3. The structure which controls operation | movement of the motors 8-12 is taken. Further, when the input device 7 is operated so as to turn the body 3 in the left-right direction, the flight control means 22 detects the flight speed detected by the speed sensor 13 of the body 3 and the input device 7. The target turning bank angle of the airframe 3 is set by calculation based on the turning yaw rate obtained from the input data, and the target turning bank angle and the actual turning bank angle of the airframe 3 detected by the attitude sensor 4 are determined. The airframe 3 is tilted so as to match.

The maximum turning bank angle setting means 23 includes a calculation means 25 for obtaining a limit value of the turning bank angle of the airframe 3 by calculation, and a correction means 26 for correcting the limit value in accordance with a flight environment condition and a flight speed. It is configured. Here, a method in which the calculation means 25 obtains the limit value of the turning bank angle will be described.
The minimum vertical thrust required to keep the unmanned helicopter stationary in the air (hovering state) is equal to the gravitational acceleration G acting on the airframe 3. For this reason, in order to fly the aircraft 3 with a turning bank angle of θ (deg) at the time of turning, when the total thrust of the helicopter is F, as shown in FIG.
F ≧ G × cos (θ) (1) must be satisfied. From this equation (1), the limit value of the turning bank angle of aircraft 3 (the maximum turning bank angle at which stable flight is possible) is
θ ≦ cos ⁻¹ (F / G) (2)

  The calculating means 25 obtains the limit value of the turning bank angle from the equation (2). When this calculating means 25 calculates | requires the said limit value, the value measured beforehand for every model as a value of the total thrust F of a helicopter is input. This limit value is a value when the air temperature and the weight of the airframe 3 are equivalent to those at the time of the measurement and are in a hovering state. The total thrust F of the helicopter changes according to the conditions of the flight environment such as air temperature and atmospheric pressure. Even if the total thrust F is constant, the thrust in terms of acceleration (from “force = mass × acceleration”) changes due to a change in the weight of the aircraft. For this reason, the limit value of the turning bank angle depends on the actual flight state (flight environment conditions and the weight of the airframe 3 are different from those at the time of measurement and the aerodynamic force is applied to the airframe 3 as the airframe 3 moves forward. Correction is performed by correction means 26 described later so as to correspond to the operating flight state).

  The correction means 26 is configured to obtain a correction coefficient for the total thrust F by utilizing a phenomenon in which the flight environment condition and the change in the weight of the airframe 3 are reflected in the opening of the throttle valve. More specifically, the correction means 26 detects the opening degree of the throttle valve by the throttle valve opening degree sensor 16, and numerical data of the correction coefficient of the total output F corresponding to the throttle valve opening degree is sent to the calculation means 25. send. The calculation means 25 to which the numerical data is sent corrects the value of the total output F based on the correction coefficient, and updates the limit value of the turning bank angle.

Further, the correction means 26 is configured to read a correction coefficient of the turning bank angle corresponding to the flight speed of the airframe 3 detected by the speed sensor 13 from the map 27 shown in FIG. 5 and send it to the calculation means 25 as numerical data. It is taken. The map 27 is formed by assigning a correction coefficient of the maximum turning bank angle (bank angle limit) to the flight speed. By sending the numerical data of the correction coefficient read from the map 27 to the calculation means 25, the calculation means 25 corrects the limit value of the turning bank angle based on the correction coefficient corresponding to the flight speed.
That is, the maximum turning bank angle setting means 23 according to this embodiment corrects the limit value of the turning bank angle unique to the airframe based on the current throttle valve opening and the flight speed, so that the conditions of the current flight environment The maximum turning bank angle at which stable flight is possible is determined based on the weight of the airframe 3 and the flight speed.

  The turning yaw rate correcting means 24 includes the actual turning bank angle of the airframe 3 detected by the attitude sensor 4 as the bank angle detecting sensor according to the present invention, and the maximum turning set by the maximum turning bank angle setting means 23. When the turning bank angle of the aircraft 3 is larger than the maximum turning bank angle, the turning yaw rate is set so that the actual turning bank angle matches the maximum turning bank angle. ing. This turning yaw rate is used when the flight control means 22 sets a target turning bank angle. Here, a method in which the turning yaw rate correcting means 24 sets the turning yaw rate as described above will be described.

The centrifugal force A (see FIG. 3) acting on the airframe 3 when the unmanned helicopter turns is assumed that the turning radius is R and the turning yaw rate is ω.
A = R × ω2 (3) At this time, since the flight speed V = R × ω,
Centrifugal force A = V × ω (4)
On the other hand, the bank angle θ when the centrifugal force and the thrust are balanced is
θ = atan (A / g) (5).
From the above equations (4) and (5), when the turning yaw rate ω is obtained under the condition that the bank angle θ and the flight speed V are constant, θ = atan (V × ω / G)
The turning yaw rate ω = G × tan (θ) / V (6).

That is, by substituting the maximum turning bank angle obtained by the maximum turning bank angle setting means 23 as the bank angle θ into the above equation (6) and substituting the value detected by the speed sensor 13 as the flight speed V, the maximum turning The turning yaw rate (ω) for turning so that the bank angle becomes θ and the flight speed becomes V can be obtained.
When the turning bank angle of the aircraft 3 is larger than the maximum turning bank angle, the turning yaw rate correcting means 24 obtains the turning yaw rate (ω) according to the equation (6) and uses the turning yaw rate (ω) as numerical data. This is sent to the flight control means 22. The flight control means 22 to which the numerical data is sent sets the target turning bank angle using the turning yaw rate (ω) indicated by the numerical data. As a result, the airframe 3 turns at a turning bank angle that does not exceed the maximum turning bank angle.

  In general, in an unmanned helicopter, changes in the turning bank angle affect the turning yaw rate and flight speed. As shown in this embodiment, by adopting a configuration that suppresses the turning bank angle by changing (decreasing) the turning yaw rate, it is possible to suppress the change in the flight speed during the turning. The stability of the aircraft can be kept high.

Here, the operations of the maximum turning bank angle setting means 23 and the turning yaw rate correction means 24 will be described with reference to the flowchart shown in FIG.
When the turning operation of the airframe 3 is performed by the input device 7, the maximum turning bank angle setting means 23, as shown in step S 1, the total thrust F corresponding to the flight environment based on the detection value of the throttle valve opening sensor 16. The correction coefficient is obtained.

Next, the maximum turning bank angle setting means 23 uses the total thrust F corrected by the correction coefficient obtained in step S1, and the limit value of the turning bank angle at a flight speed of 0 (m / s) according to the equation (2). Is obtained (step S2).
Thereafter, in step S3, the maximum turning bank angle setting means 23 reads a correction coefficient of the turning bank angle corresponding to the current flight speed from the map 27, and finally corrects the limit value by using this correction coefficient. Determine the maximum turning bank angle.

  After determining the maximum turning bank angle in this way, the turning yaw rate correcting means 24 detects the actual turning bank angle of the airframe 3 (step S4), and as shown in step S5, the actual turning bank angle of the airframe 3 and The maximum turning bank angle is compared. As a result of the comparison, if it is determined that the actual turning bank angle of the airframe 3 does not exceed the maximum turning bank angle (bank angle limit), the process proceeds from step S6 to step S8, where the turning yaw rate correcting means 24 controls the flight. A control signal indicating that the turning yaw rate is not adjusted is sent to the means 22. In this case, the flight control means 22 sets the target turning bank angle of the airframe 3 using the turning yaw rate set by the input device 7.

  On the other hand, if it is determined in step S5 that the actual turning bank angle of the airframe 3 exceeds the maximum turning bank angle (limit), the turning yaw rate correcting means 24, as shown in steps S7 to S8, A turning yaw rate suitable for the current flight speed and the maximum turning bank angle is obtained by the equation (6), and numerical data indicating the turning yaw rate is sent to the flight control means 22. As a result, the target turning bank angle of the airframe 3 becomes the maximum turning bank angle, and the airframe 3 continues turning flight in a stable state.

  Therefore, according to the unmanned helicopter control device 2 according to this embodiment, stable turning flight can be performed without being affected by the wind in the flight airspace, the weight of the airframe 3, or the like. In performing this turning flight, since the control device 2 automatically performs, it is not necessary for the aircraft operator to perform complicated calculations or complicated operations.

Since the control device 2 shown in this embodiment adopts a configuration in which the turning yaw rate is changed to keep the turning bank angle small, the change in the flight speed during turning is reduced, and the behavior of the airframe 3 is further stabilized. To come.
Further, the unmanned helicopter control device 2 according to this embodiment uses a throttle valve opening that changes according to the temperature of the flying airspace, the weight of the fuselage 3 and the flight speed, etc. (air temperature, weight of the fuselage 3 Since the configuration for obtaining the maximum turning bank angle in accordance with the (flying speed) is adopted, the stability during turning is further improved.

  In the above-described embodiment, the example in which the turning yaw rate is set to a value that matches the maximum turning bank angle when the actual turning bank angle of the airframe 3 is larger than the maximum turning bank angle. The turning yaw rate correcting means 24 can set the turning yaw rate so that the actual turning bank angle is equal to or less than the maximum turning bank angle.

  Moreover, although the flight control means 22 by embodiment mentioned above showed the thing of the structure which sets a target flight state by operating the input device 7 of the radio control device 6, the method of controlling the flight of the unmanned helicopter 1 is shown. Can be appropriately changed. For example, as the flight control means 22, it is possible to use a so-called autonomous flight type configuration in which the airframe 3 flies along a flight course stored in advance in a personal computer on the ground station side.

It is a block diagram of the control apparatus for unmanned helicopters concerning this invention. It is a block diagram of the control device for unmanned helicopters concerning the present invention. It is a figure for demonstrating the control method at the time of turning flight. It is a graph used as the map for calculating | requiring the maximum turning bank angle corresponding to a flight speed. It is a flowchart for demonstrating operation | movement of the control apparatus for unmanned helicopters which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Unmanned helicopter, 2 ... Control device, 3 ... Airframe, 4 ... Attitude sensor, 5 ... Airframe side communication device, 6 ... Radio control device, 8 ... Elevator servo motor, 9 ... Aileron servo motor, 10 ... Collective servo motor, DESCRIPTION OF SYMBOLS 11 ... Ladder servo motor, 12 ... Throttle valve servo motor, 14 ... Altitude sensor, 15 ... Direction sensor, 16 ... Throttle valve opening sensor, 21 ... CPU, 23 ... Maximum turning bank angle setting means 24 ... Turning yaw rate correction means, 25 ... calculation means, 26 ... correction means.

Claims (2)

  In a control device for an unmanned helicopter that sets a turning bank angle of an aircraft according to a flight speed and a turning yaw rate, a maximum turning bank angle setting means for obtaining a maximum turning bank angle capable of stable flight in the current flight state of the aircraft, and the aircraft When the actual bank turning angle detected by the bank angle detection sensor is larger than the maximum turning bank angle, the turning yaw rate of the aircraft is set so that the actual turning bank angle is equal to or less than the maximum turning bank angle. A control device for an unmanned helicopter, comprising: a turning yaw rate correcting means for setting. In the control device for an unmanned helicopter according to the first aspect of the invention, the maximum turning bank angle setting means obtains the thrust of the fuselage from the throttle valve opening of the engine, and corrects the maximum turning bank angle corresponding to this thrust. A control device for an unmanned helicopter provided with correction means.

Images