JP2913580B2 - Contact detection device for skid type aircraft - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact detection device for a skid-type aircraft for detecting whether or not a skid of an aircraft having a skid-type landing gear such as a helicopter is in contact with the ground.

[0002]

2. Description of the Related Art Aircraft equipped with flight control devices such as a digital autopilot system and a fly-by-wire system (all-electric control system) have landing gears such as skids or wheels grounded to the ground. Since the response of the aircraft is different between the case and the case where the aircraft is levitating in the air, it is necessary to determine whether or not the aircraft is in contact with the ground or in a levitating state, and to switch the control according to each state.

[0003] As a method of detecting whether or not the aircraft is in contact with the ground or levitating, in the case of an aircraft having a wheel type landing gear, when the aircraft is landing, the suspension of the wheels is caused by the weight of the aircraft. A method is used in which it is detected whether or not the vehicle is submerged, and when it is submerged, it is determined that the vehicle is grounded.

[0004] Further, regarding an aircraft landing gear, for example, JP-A-53-87498 and JP-A-60-116
598, JP-A-62-241800, JP-A-62-244795 and JP-A-1-3178.
No. 96 publication.

[0005]

However, in an aircraft equipped with a skid type landing gear, whether or not the skid is in contact with the ground or levitated has conventionally been determined by the operator's senses such as visual recognition. In such a case, there is a problem that the determination as to whether the skid is in contact with the ground depends on the environment such as the weather or the state of the ground.

SUMMARY OF THE INVENTION An object of the present invention is to provide a skid-type aircraft contact detection device that can easily and reliably determine whether or not the skid is in contact with the ground.

[0007]

SUMMARY OF THE INVENTION The present invention relates to a contact detection device mounted on a skid-type aircraft, comprising: a light emitting means for irradiating light downward from a contact portion of the skid; and a light from the light emitting means. Modulation means for modulating light, light receiving means for receiving light emitted from the light emitting means and reflected on the ground, demodulating means for demodulating a signal from the light receiving means, and light from the light emitting means to the light receiving means. Determining means for determining whether or not the light has arrived, wherein the light-emitting means and the light-receiving means are arranged such that a ground portion of the skid is interposed between the light-emitting means and the light-receiving means. This is an aircraft ground contact detection device. According to the present invention, since the light emitting means emits light downward from the grounding portion of the skid, when the aircraft is levitating, the light emitted from the light emitting means is reflected on the ground, and The light is received by the light receiving means via the space between the ground part and the ground. Therefore, by determining that the light from the light emitting means has reached the light receiving means, the determining means can determine that a space is generated between the skid of the aircraft and the ground. When the skid is in contact with the ground, there is no space between the ground of the skid and the ground, so the light from the light emitting means is blocked by the skid, and the light receiving means blocks the light from the light emitting means. No light is received. The determination means determines that the aircraft is grounded by determining that the light from the light emitting means has not reached the light receiving means. In this way, whether the skid is in contact with the ground is determined by whether or not light passes through the space between the skid and the ground, so that the skid can be easily contacted without being affected by the environment such as the weather. And can be accurately determined. The light emitted from the light emitting means is modulated by the modulation means and emitted from the light emitting means, and the light received by the light receiving means is demodulated by the demodulating means. Therefore, extraneous light such as sunlight can be easily distinguished from light, and the grounding state of the skid can be accurately determined.

The present invention is also a ground contact detection device mounted on a skid-type aircraft, comprising: ultrasonic transmitting means for transmitting an ultrasonic wave downward from a contact portion of the skid; and ultrasonic wave from the transmitting means. Modulating means for modulating, receiving means for receiving ultrasonic waves transmitted from the ultrasonic wave transmitting means and reflected on the ground, demodulating means for demodulating a signal from the receiving means, and ultrasonic waves from the ultrasonic transmitting means Determining means for determining whether or not the ultrasonic wave has reached the receiving means, wherein the ultrasonic transmitting means and the receiving means are arranged such that the ground portion of the skid is interposed between the ultrasonic transmitting means and the receiving means A landing detection device for a skid type aircraft, characterized in that: According to the present invention, if the aircraft levitates and a space is provided between the ground portion of the skid and the ground,
When the ultrasonic wave is modulated by the modulating means and the ultrasonic wave is transmitted below the ground surface of the skid from the ultrasonic wave transmitting means, the transmitted ultrasonic wave is reflected on the ground, and the space between the ground part of the skid and the ground is formed. The signal is received by the receiving means via the receiving means and demodulated by the demodulating means. When the skid is in contact with the ground, the ultrasonic waves from the ultrasonic transmitting means are blocked by the skid, and the ultrasonic waves reflected on the ground cannot pass between the skid and the ground, and the receiving means does not transmit the ultrasonic waves. Sound wave does not reach. The reception determining means determines whether the ultrasonic wave from the ultrasonic wave transmitting means has reached the receiving means. If the ultrasonic wave has reached the receiving means, it is determined that the aircraft is levitating.
If the ultrasonic wave has not reached the receiving means, it is determined that the skid is in contact with the ground. In this way, the ultrasonic wave reflected on the ground determines whether or not the skid is in contact with the ground based on whether or not the ultrasonic wave passes between the skid and the ground. Can be easily and accurately determined. In addition, the receiving means that receives the ultrasonic signal is relatively resistant to the effects of soil, mud, etc., even if it gets dirty. You can judge. The use of the ultrasonic wave in this manner makes it less likely to be affected by the environment such as mud and sand, so that maintenance is easy.

[0009]

FIG. 1 is a block diagram for explaining the operation of a grounding detection device 1 according to an embodiment of the present invention.
FIG. 2 is a perspective view showing the helicopter 14 including the ground detection device 1. A helicopter 14, which is an example of a skid-type aircraft, has a rotor 16 at an upper part of a body 15 and a skid 5 at a lower part. The skid 5 includes a pair of left and right skid bodies 13 extending parallel to each other along the body 15.
It is composed of a connecting member 17 for connecting the skid main body 13 and the body 15. The connection members 17 fixedly connect the vicinity of both ends in the longitudinal direction of each skid body 13 and the lower end of the body 15. In the vicinity of both ends of the pair of skid main bodies 13, ground detection devices 1a to 1d for detecting whether or not the skid 5 is in contact with the ground 4 are provided. Note that the grounding detection devices 1a to 1d are collectively referred to as grounding detection devices 1.

When the helicopter 14 is landing,
A grounding portion 8 as a lower end of the skid body 13 is grounded to the ground 4. The ground detection device 1 transmits light to the skid 5.
A light-emitting circuit 2 for irradiating downward from the grounding portion 8 of
A modulation circuit 9 for modulating light emitted from the light emitting circuit 2; a light receiving circuit 3 for receiving light emitted from the light emitting circuit 2 and reflected on the ground 4; and a demodulation circuit for demodulating a signal from the light receiving circuit 3 10 and a determination circuit 11 for determining whether or not light from the light emitting circuit 3 has reached the light receiving circuit 3.

The light emitting circuit 2 and the light receiving circuit 3 are attached to the skid main body 13 from the vicinity of the upper end 13a of the skid main body 13 via a support member 6 extending in one width direction and a support member 7 extending in the other width direction. . The light emitting circuit 2 includes, for example, a light emitting diode, and the light receiving circuit 3 includes, for example, a photodiode or a phototransistor.
The light emitting circuit 2 emits light from the light emitting unit 2a toward the lower side of the grounding unit 8 of the skid body 13. When the helicopter 14 floats and a space is created between the skid body 13 and the ground 4, the light emitted from the light emitting circuit 2 is reflected on the surface of the ground 4 and the other side in the width direction of the skid body 13. The light is received by the light receiving section 3a of the light receiving circuit 3 provided in the first position.

The modulation circuit 9 supplies a modulation signal to the light emitting circuit 2, and modulates the intensity of the light from the light emitting circuit 2 at a predetermined frequency, for example. When the light is received, the light receiving circuit 3 converts the light into an electric signal and supplies the electric signal to the demodulation circuit 10.
And demodulates the electric signal, and inputs the electric signal to the determination circuit 11. The determination circuit 11 determines whether the electric signal from the demodulation circuit 10 is higher or lower than a predetermined reference level, whereby a space is provided between the skid body 13 and the ground 4, and the helicopter 14 is floating. And judge.

Light emitted from the light emitting circuit 2 is modulated by a modulation circuit 9.
Therefore, the light can be distinguished from disturbance light such as natural light, and the light reaches the light receiving circuit 3 without fail.

FIG. 3 is a schematic diagram of the ground detection device 1 showing a state in which the skid 5 is grounded on the ground 4. When the skid 5 is in contact with the ground, there is no space between the ground portion 8 of the skid body 13 and the ground 4, so that the skid body 1
The light irradiated toward the lower side of the grounding portion 8 of the 3 and reflected on the ground 4 is blocked by the skid body 13, and the light does not reach the light receiving circuit 3. Therefore, the judgment circuit 11 is provided with the demodulation circuit 10
, An electric signal lower than the predetermined reference level is input, and it is determined that the skid 5 is grounded on the ground 4.

As described above, the light emitting circuit 2 and the light receiving circuit 3
Since the helicopter 14 is lifted up and a space is formed between the ground portion 8 of the skid 5 and the ground 4 because the helicopter 14 is mounted on both sides in the width direction with the skid body 13 interposed therebetween, light is transmitted through the space to the receiving circuit 3. When the skid 5 is grounded and there is no space between the ground portion 8 and the ground 4, the light emitted from the light emitting circuit 2 is blocked by the skid body 13 and does not reach the light receiving circuit 3. . Therefore, even when the skid 5 is slightly levitated, it can be determined that the skid 5 is not in contact with the ground, and the ground of the skid 5 can be determined with high accuracy.

The above-mentioned ground detecting devices 1a to 1d are provided near both ends in the longitudinal direction of each skid main body 13, respectively. These four ground detection devices 1a to 1d correspond to FIG.
Are respectively connected to OR (logical sum) circuits 12, and a signal indicating whether or not the skid 5 is grounded to the ground 4 is input to the OR circuit 12, and the ground detection devices 1a to 1d are provided.
If it is determined that at least one of them is grounded, the OR circuit 12 supplies a ground signal to various avionics (electric aircraft equipment).

Therefore, even if the ground 4 on which the helicopter 14 lands is not flat, and the helicopter 14 lands in a state where a part of the ground portion 8 of the skid 5 is not grounded, for example, a slight unevenness is formed by a stone or the like. When any one of the four ground detection devices 1a to 1d is grounded, it is determined that the skid 5 is grounded, so that malfunction can be prevented.

FIG. 4 is a schematic diagram showing an operation state of the ground detection device 1 when the helicopter 14 is at a predetermined altitude or higher. When the helicopter 14 is levitated above a predetermined altitude, the light emitted from the light emitting circuit 2 is applied to the ground 8 of the skid 5 as shown in FIG.
The light is emitted further downward and is reflected by the ground 4, but the reflected light passes through a position away from the light receiving section 3 b of the light receiving circuit 3, and the reception signal received by the light receiving circuit 3 is reduced.
Such a decrease in the received signal increases as the helicopter 14 moves up. However, helicopter 14
Combining the radio altimeter 18 for detecting the altitude of the ground with the ground detection device 1 to determine whether the reception signal received by the light receiving circuit 3 is small.
Alternatively, even when the value becomes 0, if the radio altimeter 18 determines that the helicopter 14 is levitating above a predetermined altitude, it is determined that the helicopter 14 is levitating. When the helicopter 14 is lower than a predetermined altitude, the light receiving circuit 3 receives sufficient light to determine the grounding.

By combining the radio altimeter 18 and the grounding detector 1 in this manner, it is possible to prevent a malfunction such as determining that the helicopter 14 is grounded when the helicopter 14 is levitating.

The grounding detection device of the present invention is not limited to a helicopter, but can be suitably applied to, for example, a glider having a skid.

FIG. 5 is a block diagram for explaining the operation of a ground detection device 20 according to another embodiment of the present invention. The grounding detection device 20 is similar to the grounding detection device 1 shown in FIGS. 1 to 4, and it should be noted that, instead of the above-described light emitting circuit 2, ultrasonic waves are directed downward from the grounding portion 8 of the skid 5. And a receiving circuit 22 for receiving ultrasonic waves transmitted from the ultrasonic transmitting circuit and reflected on the ground 4 instead of the light receiving circuit 3 described above. In FIG. 5, the same reference numerals are given to portions corresponding to the grounding detection device 1 shown in FIGS. The ultrasonic wave modulated by the modulation circuit 9 and transmitted from the ultrasonic transmission circuit 21 is reflected on the ground 4. When the skid 5 is floating, the ultrasonic wave is received by the receiving circuit 22 and demodulated by the demodulation circuit 10, and when the skid 5 is grounded, the ultrasonic wave is cut off by the skid 5 and is not received. The determination circuit 11 determines whether the skid 5 is grounded by determining whether or not the reception circuit 22 has received an ultrasonic wave.

In the helicopter 14, the receiving unit 22a may be soiled by mud or earth and sand adhered to the receiving circuit 22 depending on the state of the ground 4, but the ground detecting device 20 uses ultrasonic waves. Even if mud or the like adheres, the reception signal is prevented from being reduced, and the grounding of the skid can always be accurately determined.

[0023]

According to the present invention, since the light emitted from the light emitting means and reflected on the ground is received by the light receiving means, it is determined that the skid is floating from the ground, so that the skid is slightly lifted. Even if it does, it can be reliably determined that the aircraft is levitating. Further, when the skid is in contact with the ground, the light emitted toward the ground does not reach the light receiving means, so that it can be reliably determined that the skid is in contact with the ground. Thus, it can be easily determined whether or not the skid is in contact with the ground.

According to the present invention, whether or not the skid is grounded is determined by the ultrasonic wave transmitting means for transmitting the ultrasonic wave and the receiving means for receiving the ultrasonic wave. Even if it adheres, the reception signal received by the receiving means is prevented from being reduced, and it can be always accurately determined that the skid has touched the ground.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an operation of a ground detection device 1 according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a helicopter 14 including the ground detection device 1. FIG.

FIG. 3 is a schematic diagram of the grounding detection device 1 showing a state when the skid 5 is grounded on the ground 4;

FIG. 4 is a schematic diagram showing a state of the ground contact detection device 1 when the helicopter 14 is at a predetermined altitude or higher.

FIG. 5 is a diagram showing a ground detection device 2 according to another embodiment of the present invention.
FIG. 4 is a block diagram for explaining an operation of No. 0;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 20 Grounding detection device 2 Light emitting circuit 3 Light receiving circuit 4 Ground 5 Skid 6, 7 Supporting member 8 Grounding part 9 Modulation circuit 10 Demodulation circuit 11 Judgment circuit 12 OR circuit 13 Skid body 14 Helicopter 18 Radio altimeter 21 Ultrasonic transmission circuit 22 Receiver circuit

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-235000 (JP, A) JP-A 62-155100 (JP, U) JP-A-2-32498 (JP, U) (58) Survey Field (Int.Cl. ⁶ , DB name) B64C 25/06 B64C 25/32 B64C 25/52 B64C 27/04 B64D 45/00 B64D 45/04 B64D 47/00

Claims (2)

(57) [Claims] 1. A ground contact detection device attached to a skid type aircraft, comprising: a light emitting means for irradiating light downward from a grounded portion of the skid; and a modulating means for modulating light from the light emitting means. Light receiving means for receiving light emitted from the light emitting means and reflected on the ground; demodulating means for demodulating a signal from the light receiving means; and determining whether light from the light emitting means has reached the light receiving means. Determining means for determining whether or not the light emitting means and the light receiving means are arranged such that a ground contact portion of the skid is interposed between the light emitting means and the light receiving means. 2. A grounding detection device mounted on a skid type aircraft, comprising: an ultrasonic wave transmitting means for transmitting an ultrasonic wave downward from a grounding portion of a skid; and a modulation means for modulating an ultrasonic wave from the transmitting means. Means, receiving means for receiving ultrasonic waves transmitted from the ultrasonic wave transmitting means and reflected on the ground, demodulating means for demodulating a signal from the receiving means, and ultrasonic waves from the ultrasonic transmitting means to the receiving means. Determining means for determining whether or not the ultrasonic wave has arrived, wherein the ultrasonic transmitting means and the receiving means are arranged such that a ground portion of the skid is interposed between the ultrasonic transmitting means and the receiving means. Contact detection device for skid-type aircraft.