JP2009244192A - Device, method, and program for measuring moving body position - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the position measurement accuracy of a missile by designing a measuring method of an optical system without using a combination of a plurality of devices. <P>SOLUTION: When a laser section 1 generates and emits continuous laser pulses, a transmitting optical section 2 transmits transmitted laser pulses P1 to a target 10 at a predetermined time interval Δt. A receiving optical section 3 collects receiving laser pulses P2 reflected by the target 10, a multi-channel photodetection section 4 detects the receiving laser pulses P2 for each channel corresponding to an incidence direction, and a multi-channel ranging section 5 measures the time difference between the transmitting times of the transmitting laser pulses P1 and receiving times of the receiving laser pulses P2. A control section 8 calculates the distance to the target 10 based on the time difference measured by the multi-channel ranging section 5, and calculates the moving direction of the target 10 based on the position of the channel detected by the multi-channel photodetection section 4. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a moving object position measuring device, a moving object position measuring method, and a moving object position measuring program for measuring the position of a moving target, and in particular, the distance to a flying object at a long distance and the moving direction. The present invention relates to a moving body position measuring apparatus, a moving body position measuring method, and a moving body position measuring program that can measure simultaneously.

  Conventionally, a technology of a flying object position measuring device for measuring a distance to a moving target, in particular, a flying object such as an aircraft at a long distance, a moving direction, and a moving angular velocity thereof has been disclosed (for example, patents). Reference 1). According to this technology, even if an error angle of tracking delay occurs with respect to a flying object by position detection combining a pulse laser ranging device and an image tracking apparatus, laser light is directed to the flying object by image tracking. Thus, the position of the flying object can be accurately measured so that the flying object does not deviate from the range of the spread angle of the laser beam. In addition, the ballistic measurement of a small flying object (for example, a golf ball) is performed using a laser irradiator that irradiates the flying object with laser light and three laser receivers that receive laser light reflected from the flying object. The technique to perform is also disclosed (for example, refer patent document 2). According to this technique, the trajectory of the flying object can be measured by a triangulation method using three laser receivers spatially separated from the flying object.

In addition, a technique of a moving body position measuring apparatus as shown in FIG. 7 is also known. That is, this moving body position measuring apparatus is mounted on the scanning unit 30 of the biaxial gimbal mechanism that moves the laser ranging unit 10 and the image tracking unit 20 using the single-channel pulse laser ranging method in the left-right direction. The entire configuration is controlled by the scanning control unit 40 and the control unit 50. Thereby, the laser direction to the target 60, that is, the transmission direction of the transmission laser pulse from the laser ranging unit 10 is tracked by controlling the scanning unit 30 based on the angle data of the image tracking unit 20. The position of the target 60 can be accurately measured so that the target 60 does not deviate from the range of the spread angle of the transmission laser pulse (laser light).
JP-A-10-132935 JP-A-08-054466

  In the conventional flying object position measuring apparatus as shown in FIG. 7, the distance to the target 60 is measured by the laser ranging unit 10, and the moving direction (or moving angle) of the target 60 is detected by the image tracking unit 20. . However, since the distance to the flying object and the moving direction of the flying object are measured by separate devices, the flying object position measuring device becomes complicated and large. In addition, the flying object position measuring device disclosed in Patent Document 1 also uses the pulse laser distance measuring device and the image tracking device to measure the position and tracking of the flying object. Becomes complicated and large. Further, in the technique disclosed in Patent Document 2, in order to increase the position detection accuracy of the flying object, a large number of laser receivers that receive reflected light from the flying object must be arranged. The overall configuration of the measurement system becomes large.

  The present invention has been made in view of the above-mentioned circumstances, and does not use a combination of a plurality of devices such as a distance measuring device and a tracking device, but measures the position of a flying object by devising a measurement method using an optical system. It is an object of the present invention to provide a moving body position measuring device, a moving body position measuring method, and a moving body position measuring program that can improve accuracy.

  In order to solve the above-mentioned problems, a first configuration of the present invention relates to a moving body position measuring device that measures a propagation time of a laser pulse and measures a distance to the moving body, and at least two continuous laser pulses are provided. Is transmitted to the mobile body at a predetermined time interval, and the laser pulse reflected by the mobile body is received by each channel installed substantially at the focal position corresponding to the incident direction, and the transmission time of the laser pulse is received. The distance to the moving body is calculated based on the time difference between the time and the reception time, and the moving direction of the moving body is calculated based on two channels that have received two consecutive laser pulses.

  According to a second configuration of the present invention, there is provided a moving body position measuring method for measuring a distance to a moving body by measuring a propagation time of a laser pulse, and a first step of generating at least two continuous laser pulses; A second step of transmitting the laser pulse generated in the first step to the moving body as a transmission laser pulse at a predetermined time interval; and the laser pulse reflected by the moving body is collected by a condensing optical system. A third step of focusing as a received laser pulse, a fourth step of detecting the received laser pulse for each channel corresponding to an incident direction at a substantially focal position of the focusing optical system, and the transmission The fifth step of measuring the time difference between the transmission time of the laser pulse and the reception time of the received laser pulse, and the time difference measured in the fifth step, Calculates the distance to the body, is characterized in that it comprises a sixth step of calculating a moving direction of the moving body from the position of the channel detected by the fourth step.

  According to the configuration of the present invention, positioning based on the transmission / reception time difference between the transmission optical system that transmits a laser pulse to the target and the reception optical system that receives the laser pulse reflected from the target, and the laser pulse received by the reception optical system By combining with the detection position of the channel, it is possible to simultaneously measure the distance to the moving target, particularly the distance to the flying object at a long distance and the moving angular velocity of the target. For this reason, since the position of the flying object can be accurately measured by only one set of optical systems without using the laser distance measuring part and the image tracking part, the flying object position measuring apparatus can be reduced in size and weight. Is possible.

  First, an outline of an embodiment of the present invention will be described. A moving body position measuring apparatus as a preferred embodiment of the present invention includes a laser unit that generates at least two continuous laser pulses, and a laser pulse generated by the laser unit as a transmission laser pulse at a predetermined time interval. Transmitting optical unit for transmitting, receiving optical unit for condensing the laser pulse reflected by the moving body as a received laser pulse, and installed at a substantially focal position of the receiving optical unit, and receiving laser pulse for each channel corresponding to the incident direction A multi-channel light detection unit that detects the time difference between the transmission time of the transmission laser pulse and the reception time of the reception laser pulse, and the time difference measured by the multi-channel distance measurement unit. The distance is calculated, and the moving direction of the moving body is calculated from the position of the channel detected by the multi-channel light detector. And a control unit.

Embodiment 1

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a configuration diagram of a moving body position measuring apparatus according to a first embodiment of the present invention. In each embodiment described below, the same structural elements are denoted by the same reference numerals, and redundant description is omitted. FIG. 2 is a waveform diagram showing temporal transitions of the transmission laser pulse P1 transmitted from the transmission optical unit 2 in FIG. 1 and the reception laser pulse P2 received by the reception optical unit 3, and the horizontal axis represents time. It represents.

  First, the configuration of the moving body position measuring apparatus shown in FIG. 1 will be described. This moving body position measuring apparatus directs a laser unit 1 that generates and emits a pulsed laser beam (hereinafter referred to as a laser pulse) and a laser pulse (transmission laser pulse P1) received from the laser unit 1 toward a target 10. The transmission optical unit 2 that outputs the light, the reception optical unit 3 that collects the laser pulse (reception laser pulse P2) reflected from the target 10, and the reception optical unit 3 are installed at almost the focal position to detect the reception laser pulse P2. A multi-channel light detection unit 4 for performing the multi-channel light detection unit 4, a multi-channel distance measuring unit 5 for measuring a time difference between the transmission laser pulse P1 and the reception laser pulse P2, and optical axes of the transmission optical unit 2 and the reception optical unit 3 And a scanning control unit 7 for controlling the scanning unit 6 and a control unit 8 for controlling the entire apparatus. There.

  The function of each component will be described in more detail. The laser unit 1 generates a laser pulse with a wavelength of 1.5 μm, and transmits at least two continuous laser pulses to the transmission optical unit 2 at predetermined time intervals. For example, the laser unit 1 includes an oscillation signal of an Nd: YAG laser (laser made of yttrium, aluminum, or garnet doped with neodymium) and an OPO (Optical Parametric Oscillator) excited by an LD (Laser Diode). Are generated and transmitted to the transmission optical unit 2.

  Based on the laser pulse received from the laser unit 1, the transmission optical unit 2 generates two continuous transmission laser pulses P1 having a time interval Δt generated at time t1 and time t2 as shown in FIG. Are transmitted at a time interval of and transmitted toward the target 10. The energy of each transmission laser pulse P1 output from the transmission optical unit 2 is 200 mJ, and the pulse width is 5 ns. In addition, the receiving optical unit 3 receives the received laser pulse P2 that is reflected from the target 10 and that has a continuous time interval Δt that occurs at time t3 and time t4 as shown in FIG.

  In the multi-channel light detection unit 4, each channel is two-dimensionally or one-dimensionally arranged, and a reception signal is output from a channel corresponding to a direction in which the reception laser pulse P <b> 2 enters the reception optical unit 3. The multi-channel distance measuring unit 5 includes a plurality of distance measuring circuit units (not shown) corresponding to the respective channels of the multi-channel light detecting unit 4. Based on the control of the scanning control unit 7, the scanning unit 6 performs three-dimensional scanning of the transmission optical unit 2 and the reception optical unit 3 so that the optical axes of the transmission optical unit 2 and the reception optical unit 3 are directed toward the target 10. I do. The scanning control unit 7 transmits a control signal to the scanning unit 6 so that the transmission optical unit 2 and the reception optical unit 3 perform three-dimensional scanning. The control unit 8 calculates the distance from the measurement position (that is, the moving body position measurement device) to the target 10 based on the output signal from the multi-channel distance measurement unit 5, and at the same time, the reception laser pulse P2 is received. The moving direction of the target 10 is calculated from the channel position. Thereby, the distance to the target 10 and the moving direction of the target 10 can be detected simultaneously.

  FIG. 3 is a block diagram showing the internal configuration and peripheral portion of the transmission optical unit 2 shown in FIG. 1, and FIG. 4 is a block diagram showing the internal configuration and peripheral portion of the reception optical unit 3 shown in FIG. As shown in FIG. 3, the transmission optical unit 2 includes a beam expander 201 in which a convex lens 201a and a concave lens 201b are arranged on a straight line. By controlling the lens interval between the convex lens 201a and the concave lens 201b of the beam expander 201 by the control unit 8 (see FIG. 1), the spread angle Ωt of the transmission laser pulse P1 can be controlled between 0.5 and 5 mrad. it can.

  As shown in FIG. 4, the reception optical unit 3 is configured by arranging a reception telescope 301 and a zoom optical system 302 on a straight line. The photodetector array 401 is a constituent element of the multi-channel photodetector 4 (see FIG. 1). In FIG. 4, the receiving telescope 301 is schematically represented by a single convex lens, but in actuality, it is a Cassegrain type telescope composed of a parabolic primary mirror and a hyperboloid secondary mirror. The effective diameter of the reception telescope 301 is 200 mm. By controlling the effective focal length combined with the zoom optical system 302 by the control unit 8, the viewing angle Ωr of the reception laser pulse P2 is substantially equal to the spread angle Ωt of the transmission laser pulse P1. Controls to match.

  1 is a two-dimensional APD (Avalanche Photo Diode) array in which each channel is two-dimensionally arranged, and is configured by a photodetector array 401 as shown in FIG. Here, the photodetector array 401 is configured using 10 × 10 elements. The element spacing of each channel is 0.1 mm.

FIG. 5 is a diagram schematically showing the relationship between the directions of the multi-channel light detection unit 4 and the target 10, where (a) is a plan view and (b) is a side view. . As shown in FIG. 5B, the received laser pulse P2 first detected in the A channel of the photodetector array 401 is detected in the B channel after a predetermined time due to the movement of the flying object. That is, as shown in FIG. 5A, when the detection position of the photodetector array 401 moves from the A channel to the B channel, the angle of the received laser pulse P2 in the EL (Elevation) direction (elevation direction) is ΔΩ. and _EL changes, the angle of AZ (azimuth) direction (azimuth direction) will have been changed [Delta] [omega _AZ. When the viewing angle Ωr of the received laser pulse P2 shown in FIG. 4 is 1 mrad, the angular resolution in the EL direction (elevation direction) and the AZ direction (azimuth direction) is 0 in FIGS. .1 mrad.

  The multi-channel distance measuring unit 5 includes a plurality of distance measuring circuits (not shown) corresponding to the respective channels of the multi-channel light detecting unit 4. The ranging circuit of the multi-channel ranging unit 5 is a time-of-flight ranging circuit that measures the propagation time of light and calculates the distance to the object, and includes the transmission time of the transmission laser pulse P1, The distance to the target 10 is calculated by measuring the time difference from the reception time of the received laser pulse P2 input to any channel of the multi-channel light detection unit 4, that is, the number of clocks of the distance measuring counter. The frequency of the distance measuring counter is 50 MHz, which corresponds to the case where the distance resolution is 3 m.

  The scanning unit 6 includes a two-axis gimbal that is driven left and right like a pendulum by a general stepping motor. On this biaxial gimbal, a laser unit 1, a transmission optical unit 2, a reception optical unit 3, a multi-channel light detection unit 4, and a multi-channel ranging unit 5 are installed. The scanning range of the scanning unit 6 is 360 degrees in the Az direction (azimuth angle direction), 0 to 70 degrees in the EL direction (elevation angle direction), the maximum rotational angular velocity is 1 degree / second, and the angular resolution is 0.01 degrees (0 .18 mrad).

  The scanning control unit 7 is a device that controls the rotation axis of the scanning unit 6, that is, a control device that controls the direction of the reception visual field center. The control unit 8 includes an interface between a normal CPU and peripheral devices. The control unit 8 controls the entire moving body position measuring device, calculates the distance to the target 10 based on the output signal of the multi-channel distance measuring unit 5, and simultaneously the position of the channel from which the received laser pulse P2 is received. From the above, the moving direction of the target 10 is calculated.

  Next, the operation of the moving body position measuring apparatus shown in FIG. 1 will be described. The laser unit 1 generates two continuous laser pulses (transmission laser pulse P1) as shown in FIG. 2 at a predetermined time interval, and emits the laser beam toward the target 10 from the transmission optical unit 2. As shown in the diagram showing the relationship between the multi-channel light detection unit 4 and the direction of the target shown in FIG. 5, for example, the first transmission laser pulse P1 is emitted toward the target 10 at time t1 in FIG. It is assumed that the received laser pulse P2 that is a pulse is input to the A channel of the photodetector array 401 in the multi-channel photodetector 4 at time t3.

At this time, the time interval between the transmission laser pulse P1 at time t1 and the reception laser pulse P2 at time t3 is measured using the A channel signal of the multi-channel distance measuring unit 5. Based on the measured time interval, the distance R to the target 10 is given by equation (1).
R = c (t3-t1) (1)
Here, c is the speed of light in the atmosphere.

  Subsequently, after time Δt, the second transmission laser pulse P1 is emitted toward the target 10 at time t2, and the received laser pulse P2 at time t4, which is a reflection pulse thereof, is detected by the photodetector array in the multi-channel photodetector 4. Suppose that it is input to channel B 401 (see FIG. 5). At this time, since the time Δt is a small value (for example, 1 to 100 ms), the distance measured from the B channel signal is almost the same as the A channel.

  The spatial positions of the A channel and the B channel of the multi-channel light detection unit 4 as shown in FIGS. 5A and 5B correspond to the incident direction of the reception laser pulse P 2 incident on the reception optical unit 3. The direction in which the target 10 has moved during the time Δt can be calculated from the relative positions of the two channels (A channel and B channel) incident on the received laser pulse P2. When the plurality of photodetectors (that is, the photodetector array 401 in FIG. 4) of the multi-channel photodetector 4 are arranged in a two-dimensional array (that is, A and B) as shown in FIG. The moving direction and moving angular velocity of the target 10 in the Az direction (azimuth angle direction) and the EL direction (elevation angle direction) can be detected from the positions of the A channel and the B channel.

For example, the moving angular velocity ωEL in the EL direction is expressed as in Expression (2).
ωEL = ΔΩEL / Δt (2)

  The transmission optical axis of the transmission laser pulse P1 and the reception optical axis of the reception laser pulse P2 are adjusted to coincide with each other. At the same time, the spread angle Ωt of the transmission laser pulse P1 as shown in FIG. The viewing angle Ωr of the received laser pulse P2 is adjusted to be substantially the same. The viewing angle Ωr of the received laser pulse P2 needs to be set larger than the angle at which the target 10 moves during the time Δt. If the approximate moving angular velocity of the target 10 is known, the viewing angle of the received laser pulse P2 Setting the angle Ωr is relatively easy.

  For example, when the target 10 is moving about 50 km away in the direction perpendicular to the line-of-sight direction at a speed of 1000 m / s, Δt is set to 10 ms, and the moving angle therebetween is 0.2 mrad. Therefore, the viewing angle Ωr of the received laser pulse P2 may be set to about 1 mrad. The viewing angle Ωr of the reception laser pulse P2 and the spread angle Ωt of the transmission laser pulse P1 can be easily controlled by providing the reception optical unit 3 and the transmission optical unit 2 with a zoom function, respectively. Further, even when the viewing angle Ωr of the fixed reception laser pulse P2 is changed, the time Δt is changed in accordance with the moving angular velocity of the target 10, and when the moving angular velocity of the target 10 is large, the time Δt is reduced to reduce the target 10 to the receiving laser. It can be captured within the viewing angle Ωr of the pulse P2.

  In order to detect the distance and the moving direction of the target 10 while continuously tracking the target 10, the control unit is arranged so that the channel receiving the received laser pulse P2 from the target 10 is always at the center of the receiving field. It is necessary to control the direction of the rotation axis of the scanning unit 6 with a command from 8. For this purpose, when the next measurement of the continuous transmission laser pulse P1 is performed, the scanning unit 6 is controlled so that the channel that has received the second reception laser pulse P2 is at the center of the reception visual field. Alternatively, the moving direction of the target 10 is predicted and the scanning unit 6 is controlled in that direction.

Embodiment 2

  In the first embodiment, a two-dimensional APD array element is used as the multi-channel light detection unit 4. However, when the moving direction of the target 10 is almost constant, only the distance and the moving angular velocity need be detected. May be a one-dimensional APD array element.

  FIG. 6 is a block diagram showing an internal configuration of the second embodiment in the receiving optical unit 3 shown in FIG. In the second embodiment, instead of using the two-dimensional APD array of the first embodiment, a group of photodetectors including a two-dimensionally arranged optical fiber array 402 and a plurality of single APD elements connected to each fiber. The receiving optical unit 3 is configured by the combination of 403. The interval between the optical fiber arrays 402 is 0.1 mm, and the array arrangement method is a 10 × 10 two-dimensional array as in the first embodiment.

  In order to make the received laser pulse P2 incident on the optical fiber array 402, the optical parameters of the zoom optical system 302 need to be changed from those in the first embodiment, but other configurations are the same as those in the first embodiment.

The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and there are design changes and the like without departing from the gist of the present invention. Are also included in the present invention.
For example, it is also possible to incorporate the image tracking unit 20 (see FIG. 7) as described in the prior art, and to make tracking of the target easier by using this together with the tracking method of the first embodiment. Further, in the first and second embodiments, the function of changing the spread angle Ωt of the transmission laser pulse P1 and the viewing angle Ωr of the reception laser pulse P2 is provided. If the viewing angle Ωr is sufficient, these variable functions may be deleted. Further, the basic functions of the present invention are the same even if the wavelength and output of the laser used are changed. These parameters may be changed according to the type of target and moving speed.

  The moving body position detection apparatus of the present invention can be effectively used for position detection and tracking of a distant flying object such as a rocket or an aircraft.

It is a block diagram of the moving body position measuring apparatus which concerns on 1st Embodiment of this invention. It is a wave form diagram which shows the time transition of the transmission laser pulse transmitted from the transmission optical part of FIG. 1, and the reception laser pulse which a reception optical part receives. It is a block diagram which shows the internal structure and peripheral part of the transmission optical part shown in FIG. It is a block diagram which shows the internal structure and peripheral part of a receiving optical part shown in FIG. It is the figure which represented typically the relationship between the direction of a multichannel photon detection part and a target, the figure (a) is the figure seen planarly, and the figure (b) is the figure seen from the side. It is a block diagram which shows the internal structure of 2nd Embodiment in the receiving optical part shown in FIG. It is a block diagram of the conventional mobile body position measuring apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laser part 2 Transmission optical part 3 Reception optical part 4 Multichannel light detection part 5 Multichannel ranging part 6 Scanning part 7 Scan control part 8 Control part 201 Beam expander 301 Reception telescope 302 Zoom optical system 401 Photodetector array 402 Optical fiber array 403 Photodetector group

Claims (10)

A moving body position measuring device that measures the propagation time of a laser pulse and measures the distance to the moving body,
At least two consecutive laser pulses are transmitted to the moving body at a predetermined time interval, and the laser pulses reflected by the moving body are received by each channel installed substantially at the focal position corresponding to the incident direction. The distance to the moving body is calculated based on the time difference between the transmission time and the receiving time of the laser pulse, and the moving direction of the moving body is calculated based on two channels that have received two consecutive laser pulses. A moving body position detecting device. A moving body position measuring device that measures the propagation time of a laser pulse and measures the distance to the moving body,
A laser section for generating at least two successive laser pulses;
A transmission optical unit that transmits a laser pulse generated by the laser unit to the moving body as a transmission laser pulse at a predetermined time interval; and
A receiving optical unit that focuses the laser pulse reflected by the moving body as a received laser pulse;
A multi-channel light detection unit which is installed at a substantially focal position of the reception optical unit and detects the reception laser pulse for each channel corresponding to the incident direction;
A multi-channel distance measuring unit for measuring a time difference between a transmission time of the transmission laser pulse and a reception time of the reception laser pulse;
Calculating a distance to the moving body based on the time difference measured by the multi-channel ranging unit, and calculating a moving direction of the moving body from the position of the channel detected by the multi-channel light detecting unit; A moving body position measuring device comprising: A scanning unit that three-dimensionally drives the transmission optical unit so that the transmission laser pulse is directed toward the moving body and three-dimensionally drives the reception optical unit so that the reception laser pulse from the moving body is received. When,
The moving body position measuring apparatus according to claim 2, further comprising: a scanning control unit that drives and controls the scanning unit. Furthermore, an image tracking device that tracks the image of the moving body is provided,
The image tracking device and the scanning control unit are used together to drive and control the scanning unit, and the transmission optical unit is driven so that the transmission laser pulse is directed toward the moving body. 3. A moving body position measuring apparatus according to 3.   The time interval between the plurality of laser pulses generated by the laser unit, the spread angle of the transmission laser pulse output from the transmission optical unit, and the viewing angle of the reception laser pulse input to the reception optical unit are the moving body. 5. The moving body position measuring apparatus according to claim 2, wherein the moving body position measuring apparatus can be changed simultaneously or individually in accordance with a distance up to and an angular velocity of the moving body.   6. The moving body position detection apparatus according to claim 2, wherein the multi-channel light detection unit is configured by a one-dimensional or two-dimensional array type detector.   7. The moving body position according to claim 2, wherein the multi-channel light detection unit includes an optical fiber array and a number of photodetector groups corresponding to the number of channels. Detection device. A moving body position measuring method for measuring a propagation time of a laser pulse and measuring a distance to the moving body,
A first step of generating at least two consecutive laser pulses;
A second step of transmitting the laser pulse generated in the first step to the moving body as a transmission laser pulse at a predetermined time interval;
A third step of condensing the laser pulse reflected by the moving body as a received laser pulse by a condensing optical system;
A fourth step of detecting the received laser pulse for each channel corresponding to the incident direction at a substantially focal position of the condensing optical system;
A fifth step of measuring a time difference between a transmission time of the transmission laser pulse and a reception time of the reception laser pulse;
A sixth step of calculating a distance to the moving body based on the time difference measured in the fifth step, and calculating a moving direction of the moving body from the position of the channel detected in the fourth step;
A moving body position measuring method comprising:   9. The moving body position measuring method according to claim 8, further comprising a seventh step of controlling an irradiation direction so that the transmission laser pulse is directed toward the moving body.   A moving body position measuring program for causing a computer to execute the moving body position measuring method according to claim 8 or 9.

Images