JPH01317896A - Controller for altitude of helcopter - Google Patents

Abstract

PURPOSE:To prevent a helicopter from climbing to at least a predetermined altitude by providing a float provided with a landing detecting switch through a predetermined length of a rope in a fuselage of a remote control system unmanned helicopter so that an altitude receiving signal is corrected to the low altitude when the helicopter reaches at least the predetermined altitude. CONSTITUTION:A rope 8 is suspended through a bracket 2a from a fuselage 2 of an unmanned helicopter 1 remote controlled by a radio control or the like for sprinkling agricultural chemicals, and provided on the lower end with a float 9 formed of foamed polstyrene or the like. The float 9 is provided with a mercury switch 10 to constitute a landing type altitude detecting device 7 which is turned on in landing and turned off in taking-off. The altitude signal of remote control signal by a pilot is employed when the helicopter is in the altitude within the length of the rope and said signal is corrected to the low altitude side of altitude receiving signal when in the altitude higher than the length of the rope. When the helicopter is located in a remote place and the altitude is difficult to grasp visually, it is prevented effectively from climbing to at least the predetermined altitude.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an altitude control device for an unmanned helicopter, for example, for spraying agricultural chemicals, which is remotely operated by radio control or the like. The present invention relates to a device that allows accurate control of flight altitude even in the event of a flight.

[Conventional technology]

For example, when spraying chemicals on farmland, forests, etc., it is conceivable to use a remote-controlled unmanned helicopter. In this case, the operator operates the transmitter to fly the helicopter along the spraying area, but in this chemical spraying, the chemical may leak out to the periphery of the spraying area, or conversely, there are areas where it is not sprayed. It is necessary to make sure that no residue remains. For this purpose, it is necessary to improve the control precision of the flight range and flight altitude of the helicopter. especially,
If the flight altitude is too high, there is a risk that the medicine will be blown away by wind speed, wind direction, etc.

[Problem that the invention seeks to solve]

However, when spraying chemicals using the unmanned helicopter mentioned above,
Since the flight area is generally wider, the helicopter flies at a much greater distance from the pilot. Therefore, in the method of controlling the flight position of the helicopter while visually observing the helicopter, it is difficult to grasp the flight altitude, and the altitude control B tends to be inaccurate.

The present invention was made in view of the above-mentioned situation of chemical spraying, and an object of the present invention is to provide an altitude control device for an unmanned helicopter that can significantly improve altitude control accuracy.

[Means for solving problems]

The present invention provides an altitude control device for a helicopter configured to control the altitude according to an altitude indication signal from an operator, including an altitude detection means, and when the detected altitude is higher than a reference altitude, the altitude indication signal is sent to a low altitude. It is characterized by comprising a correction means for correction on the side.

Here, the altitude detection means in the present invention may have various structures. For example, a float may be suspended from the aircraft body with a lobe of a predetermined length (corresponding to the reference altitude), and the float may be grounded to the ground. This is a ground-based altitude detection device that is equipped with a switch that turns on and off depending on the slope.It detects altitude by atmospheric pressure, or by emitting ultrasonic waves, light, radio waves, etc. to the ground surface and detecting the altitude by reflection. Both non-contact altitude detection devices can be adopted.

[Effect]

According to the altitude control device according to the present invention, when the detected altitude is below the reference altitude, the altitude is controlled to the same altitude as the altitude instruction signal from the pilot, but when the detected altitude is higher than the reference altitude, the altitude instruction signal from the pilot is Corrected to lower altitude. Therefore, even if the pilot cannot accurately determine the helicopter's altitude because the helicopter is flying far away, the helicopter's flight altitude will not be higher than the standard altitude, and as a result, if the helicopter is used for spraying chemicals. Since the chemical is less likely to be blown away by wind or the like, the spray area can be controlled with greater precision.

In addition, if a ground type is used as the altitude detection means, the structure is simple and the altitude detection accuracy can be improved. For example, in the case of a non-contact type, ultrasonic waves are absorbed by grass, grass, etc. In addition, in the case of light, it is reflected from the bottom of the water, so there is a concern that accuracy may deteriorate depending on the usage, but in the case of a contact type, there is no such concern.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 to 5 are diagrams for explaining an altitude control device for an unmanned helicopter according to an embodiment of the present invention, and this embodiment is an example in which a ground-type altitude detection means is adopted.

In the figure, reference numeral 1 denotes a remotely controlled unmanned helicopter for spraying agricultural chemicals. Legs 3 for supporting the helicopter 1 are attached to the front lower part of the body 2 of the helicopter 1. A main rotor 4 is attached to an output shaft extending vertically upward from the engine mounted inside the front part. In addition, the main rotor 4 is located at the rear end of the fuselage 2.
A tail rotor 5 is provided to cancel the reversal torque caused by the engine, and the rotor 5 is driven by the engine via a transmission belt. Note that 6 is a tail fin to ensure stability when moving forward.

Furthermore, a support bracket 2a extending forward is fixed to the front end of the body 2. A rod-shaped float 9 made of foamed polystyrene is suspended from the front end of the bracket 2a by a row 18 having a length corresponding to the reference altitude, and a mercury switch IO is attached to the float 9. This constitutes a grounded altitude detection device 7 in which when the float 9 touches the ground, it falls in either direction and the mercury switch 10 is turned on.

By the way, when the float 9 is on the ground, the rope 8
At this time, it is necessary to take special care in the shape of the connecting part between the float 9 and the lobe 8 so that it does not get caught on the crops being sprayed with pesticides. For example, as shown in Fig. 3+al. Rather than connecting one rope 18 to one center of the float 9, it is preferable to branch it into a plurality of ropes 8a and connect them to the periphery of the float 9, as shown in Figure 3. .

Further, the mercury switch IO is connected to the altitude control device L4 mounted on the aircraft body 2 through a conductive wire &113. A receiver 15 is connected to this control device 14.
The output of is connected to an amplifier 16, and a servo mechanism 17 is driven by the amplifier 16. In this way, this helicopter l receives instruction signals from a transmitter on the ground indicating altitude 1, horizontal position, etc. with the receiver 15 mounted on the aircraft body, and receives a drive signal from the control device 15 based on the signal. It is output to the servo mechanism 17 via the amplifier 16, and the mechanism 1
7 controls the pinch angle etc. of the rotor 4, thereby allowing remote control.

The control device 14 includes a CPU 14 as shown in FIG.
The instruction signal P is sent to a via the receiver 15.

(When the pulse width tJ is input, the CPU 14a
The drive signal Pg is output from the amplifier 16 to the amplifier 16. In addition, the mercury switch 10 has 1iii
It is connected between Vcc and ground, and the connection point with the power supply Vcc is connected to the base of transistor 14b. The connection point of this transistor 14b with the power supply Vcc is connected to the CPU 14a, and is inputted as a high/low correction signal P.

In this way, the CPU 14a receives the pulse width 1.0 from the receiver 15 during low altitude flight when the mercury switch 10 is on and the correction signal P0 is high. The altitude indication signal P is output to the amplifier 16 with the same pulse width, and the correction signal P is outputted to the amplifier 16 with the same pulse width.
During high-altitude flight when , is low, the pulse width is above [. t. It is designed to be corrected and output.

Next, the effects of this embodiment will be explained.

In the helicopter 1 of this embodiment, the altitude instruction signal P from the transmitter by the pilot, as well as longitudinal and lateral position instruction signals are received by the receiver 15, and the longitudinal and lateral position signals are received by the CPU 14a.
The signal is supplied as it is to the amplifier 16 via the servo mechanism 17, which changes the forward tilt angle of the rotor 4, etc., and controls the longitudinal and lateral positions of the helicopter 1.

On the other hand, the altitude instruction signal P is input to the amplifier 16 as is when the altitude is low, and after being corrected to t when the altitude is above the reference height.

First, the operation of the correction signal P0 will be explained.

When the altitude is low, as shown in FIG. 2, the float 9 touches the ground and falls down, which turns on the mercury switch 10. Then, in FIG. 4, the base voltage of the transistor 14b decreases and turns off, and the correction signal P becomes high.
On the other hand, when the altitude becomes higher than the reference altitude determined by the length of the row 18, the float 9 stands up and the mercury switch 10 turns off.

Then, the transistor 14b turns on and the correction signal P is generated. becomes low.

Next, the operation of the CPU 14a will be explained along the flowchart of FIG.

When the operation starts, it is determined whether the pulse of the altitude indication signal P is input, and the pulse width of Pl is determined.

(step Sl, 52), and then a correction signal P. If the altitude is high, it is assumed that the altitude is lower than the reference altitude, and the output instruction signal P3 is input pulse width t,
The height is output to the amplifier 16 in the same width as in step S5), and as a result, the altitude is controlled as instructed by the pilot. On the other hand, if the altitude is low, it is determined that the altitude is higher than the standard altitude, and
The altitude indication signal P1 with a pulse width t0 is changed to a pulse width t, xl+
-tM altitude indication signal P! is corrected and output to the amplifier 16 (step S4).

Here, t and l are values for correcting the altitude indication signal P. This setting of tyo makes it possible to satisfy the following conditions. That is, ■ The value is sufficient to correct the instruction signal from the pilot during normal flight, and ■ The instruction signal from the pilot when increasing altitude during abnormal situations such as danger avoidance is corrected by [Il]. The value must also be such that the altitude can be increased.

In this way, in this embodiment, if the detected altitude is lower than the reference altitude, the altitude is controlled according to the pilot's instruction signal, and if it is higher than the reference altitude, the pilot's instruction signal is corrected to the lower altitude side. As a result, the helicopter can always fly stably below the reference altitude, and the accuracy of altitude control can be improved even when the helicopter 1 is located far away and it is difficult to visually grasp the altitude.

In addition, in this embodiment, the float 9 is used as the altitude detection means.
Since the ground-based altitude detection device 7 is used, in which the detection switch is turned on and off in the tilted state when the robot touches the ground, the structure is very simple and reliable altitude detection is possible.

By the way, in the case of the method of determining the altitude based on the tilted state of the float when it touches the ground, there is a concern that the mercury switch 10 may malfunction depending on the direction in which the float 9 falls. It is desirable to attach multiple pieces around 9.

On the other hand, in the case of the structure shown in Figure 6, if the float is subjected to acceleration in the direction of arrow G, as shown in Figure 6, when the float is dragged in a fallen state, the mercury moves and malfunctions. There are concerns.

FIG. 7 shows an altitude detection device that can eliminate the above concerns. In the figure, 11 is a pair of styrofoam plates 11.
A and 11b are connected to each other so that they can be opened and closed.

A limit switch 12 is disposed between the styrofoam plates 11a and 11b, and is turned off when the float 11 falls down and the space between the drawing boards narrows.A pair of mercury switches 10a are provided at the tip of each. , 10b are arranged such that the detection section is located on the lower side.

In this altitude detection device, when the altitude is above the reference altitude, all the switches 12, 10a and 10b are turned on, as shown in Figure 7 (al, (bl), and it is determined that the altitude is high.

Furthermore, when the aircraft touches the ground and falls down, the limit switch 12 and the switch lOa are turned off, as shown in dl in the same figure, and it is determined that the altitude is low.

If you are dragged while lying down, switches 10a and 10b are turned on but the limit switch 12 is turned off, as shown in +dl in the same figure, so it is determined that you are at a low altitude, and there is no malfunction, and the sudden brake is applied. In this state, as shown in the same figure (C1), the limit switch 12
is turned on, but switches toa and 10b are turned off, so there is no malfunction in this case as well.

In the above embodiment, the altitude is determined by the inclination of the float as a ground-based altitude detecting means. However, various modifications can be made to the altitude detecting means of the present invention. For example, as shown in FIG. The one shown in FIG. 9 may also be used.

FIG. 8 shows an example in which a weight 19 is attached to the upper side of a spherical airbag 18, and a detection device 7 including a pressure sensor 20 with a temperature compensation function is connected to the lower end of a rope 8. In the case of this detection device 7, when the altitude decreases and the airplane touches the ground, the airbag 18 is compressed by the weight 19, and the internal pressure increases, so the output of the pressure sensor 20 changes, and thereby the altitude can be detected.

FIG. 9 shows an example in which a large number of plates 21a and a pressure sensor 20 with a temperature compensation function are attached to a rod-shaped airbag 21. In this case as well, since the internal pressure changes when it touches the ground,
This pressure change can be used to detect altitude.

By the way, in the method of suspending the float 9 or the airbag 18.21 with the rope 8 described above, as shown in FIG. There is a concern that it may malfunction. The same figure (bl, (C1) is an example in which such a problem can be solved, and a contact switch consisting of a metal ring 22 and a contact piece 23 is provided in the middle of the row 18. In this example, , when the rope 18 is caught in the crop 24 and the rope 8 is tilted significantly, the contact switch is activated, thereby detecting a drop in altitude.

In the above embodiment, an example of a ground-based altitude detection means was explained, but the altitude detection means of the present invention can be of various other types. A device that calculates altitude from the atmospheric pressure of
A system that detects altitude by emitting ultrasonic waves, light, or radio waves onto the ground surface and receiving reflected waves from the waves can be used.

Further, although the above embodiments have been described with respect to unmanned helicopters, the present invention can of course be applied to manned helicopters.

[Effects of the Invention] As described above, according to the helicopter altitude control device according to the present invention, when the detected altitude is higher than the reference altitude, the altitude instruction signal from the pilot is corrected to the lower altitude side. ,
Even if it is difficult to visually grasp the altitude because the helicopter is located far away, it is possible to prevent the helicopter from climbing above a certain altitude, which has the effect of improving altitude control accuracy accordingly.

[Brief explanation of the drawing]

1 to 5 are diagrams for explaining an altitude control device for an unmanned helicopter according to an embodiment of the present invention, and FIG.
The figure is a side view showing the overall configuration, Figure 2 1al, (b
l is a side view showing its grounding state, Fig. 2 1al, (b
) is a perspective view showing the float, FIG. 4 is a block diagram of its control device, FIG. 5 is a flowchart thereof, FIG. 6 (al), (bl is a side view showing a modified example of the float, and FIG. 7 (Al is a perspective view showing another modification of the float,
Fig. 7 (bl, (cl, +dl) is a side view showing its operation, Fig. 8 (屹伽) and Fig. 9 (a), lb) are side views showing still other modifications of the float, Fig. 10 Figure 1a
1 to (1)+1 are side views showing modified examples of the altitude detection means. In the figure, 1 is a helicopter, 2 is a fuselage, 7 is an altitude detection means, 14 is a control device (correction means), 8 is a rope, 9 is a float, 10 is a mercury switch, and 15 is a receiver. Patent Applicant Yamaha Motor Co., Ltd. Agent Patent Attorney Tsutomu Shimofu Figure 1 Figure 3 Figure 4/ Figure 5 (a) Figure 6 Figure 8 (a) (b) Figure 9 (a) ( b) 70,000 watts 77π' Figure 10(c)

Claims (2)

[Claims] (1) In a helicopter altitude control device configured to receive an altitude instruction signal from a transmitter on the ground with a receiver mounted on the aircraft and control the altitude of the aircraft according to the instruction signal, An altitude control device for a helicopter, comprising a detection means for detecting an altitude, and a correction means for correcting the received altitude instruction signal to a lower altitude when the detected altitude is higher than a reference altitude. (2) The altitude detecting means is a ground-based altitude detecting device configured by suspending a float from the aircraft body with a rope of a predetermined length, and attaching a switch to the float that turns on and off depending on the grounding state of the float. An altitude control device for a helicopter according to claim 1, characterized in that: