JP2006266801A - Collision-preventing device and vehicle with it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a collision-preventing device adaptable to an actual traveling vehicle. <P>SOLUTION: The collision-preventing device comprises a device for acquiring the three-dimensional information of an object to be measured using laser beam and a computer for outputting a signal to a braking means of a mobile unit or an alarm installed in the mobile unit. The device 12 for acquiring three-dimensional information comprises a laser beam irradiation unit 20, an optical unit 30 for receiving incoming laser beam reflected off the object to be measured, and a radar circuit unit 50 for calculating the phase difference between the laser beam from the laser beam irradiation unit 20 and the laser beam received by the optical unit 30. The optical unit 30 is provided with a spatial modulator 38 which forms a reflection plane in accordance with different patterns of the number corresponding to the resolving power of the acquired three-dimensional information and guides the incoming laser beam to a light receiving section. The laser beam irradiation unit 20 is provided with a lens 22 for diffusing the laser beam to be irradiated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention detects an obstacle or the like existing in the traveling direction of the moving body, and prevents collision / contact with the detected obstacle or the like by interlocking with a braking means or the like mounted on the moving body. More particularly, the present invention relates to a collision prevention device that detects an obstacle or the like using electromagnetic waves, and a vehicle equipped with the collision prevention device.

As a vehicle collision prevention device that uses electromagnetic waves, particularly laser light, to prevent a vehicle collision, there is one disclosed in Patent Document 1, for example.
The anti-collision device disclosed in Patent Document 1 is equipped with a device that measures the distance with a laser beam on a vehicle, measures the distance to another vehicle traveling in front of the own vehicle, or an obstacle, By calculating the relative speed between the two, the degree of risk that the own vehicle will collide with another vehicle is calculated. Furthermore, Patent Document 1 describes that an alarm device that operates by detecting the degree of danger and an actuator that controls an accelerator, a brake, and the like are attached to maintain a safe distance from other vehicles.

Also, Patent Document 2 discloses that ranging is performed using laser light and this is used for collision prevention. The technique disclosed in Patent Document 2 is a collision prevention device for a self-supporting traveling vehicle. In Patent Document 2, a range (obstacle detection range) for irradiating a laser beam is determined, and whether or not an obstacle is detected within the obstacle detection range is detected, and a distance from the obstacle is measured. The vehicle is decelerated and stopped and an alarm is issued. According to such an apparatus, it can be easily determined whether an obstacle exists in the traveling direction of the host vehicle.
JP-A-6-131598 JP 2003-233423 A

  According to the device disclosed in Patent Document 1, it can be said that it is effective in preventing collision in a vehicle train that travels in a disciplined manner. However, the vehicle that actually travels is not limited to the prescribed travel line, and may change lanes or meander. Thus, when the position of the vehicle to be measured is uncertain, it is considered that it is substantially difficult to measure the relative speed between the own vehicle and another vehicle only by distance measurement.

  In addition, it is considered that the device disclosed in Patent Document 2 can be effectively used for a vehicle traveling indoors with few disturbing elements. However, when traveling on an outdoor roadway, it is considered difficult to determine what can be an obstacle and what is not an obstacle only by distance measurement.

In both Patent Documents 1 and 2, when receiving the laser beam, the laser beam is reflected using a polygon mirror, a galvanometer mirror, etc., so it is necessary to have a motor for rotating the mirror, and the device itself. There is a problem of increasing the size. Further, the distance measurement using the conventional laser beam performs a process of irradiating the spot type laser beam and sequentially calculating the three-dimensional data for each point irradiated with the laser beam to obtain the entire three-dimensional data. For this reason, it takes time to perform the calculation process from the laser irradiation until the entire three-dimensional data is acquired. For this reason, even though it is theoretically possible, in practice, measurement has not been able to cope with a practical vehicle speed.
An object of the present invention is to provide a collision prevention device capable of dealing with an actual traveling vehicle and a vehicle equipped with the collision prevention device.

  In order to achieve the above object, a collision preventing apparatus according to the present invention includes a three-dimensional information acquisition apparatus that acquires three-dimensional information of a measurement object using a laser beam, and a braking of a moving body based on the acquired three-dimensional information. Or a collision prevention device comprising a calculation means for outputting a signal to an alarm device provided in a moving body, wherein the three-dimensional information acquisition device comprises a laser light irradiation unit for irradiating a laser beam and an irradiated laser beam. Among them, an optical unit that receives laser light that has been reflected by the measurement target surface, a radar circuit unit that calculates a phase difference between the laser light emitted from the laser light irradiation unit and the laser light received by the optical unit, In the optical unit, a reflection surface is formed according to a number of different patterns corresponding to the resolution of the three-dimensional information to be acquired, and an incoming signal is received. Includes a spatial modulator for guiding laser light to the light receiving portion, the said laser beam irradiation unit, characterized by comprising a lens for diffusing the laser beam to be irradiated.

In the collision preventing apparatus having the above configuration, a micromirror array may be employed for the spatial modulator.
In the micromirror array, it is preferable that the reflection surface is constituted by at least half or more mirrors in each pattern.

The lens may be a cylindrical lens, and the laser beam may be irradiated in a fan shape, and the micromirror array may be configured so that the micromirrors are arranged in one row in the moving body width direction in correspondence with the fan-shaped laser beam. .
In order to achieve the above object, a vehicle equipped with a collision prevention device according to the present invention is equipped with the collision prevention device having the above configuration.

  With the collision prevention device having the above-described configuration, all of the laser beams that have been diffusely irradiated can be imaged on the reflecting surface that is configured for each pattern. For this reason, light reception is performed for the same pixel for each pattern in which the reflection surface corresponding to one pixel is configured, and the light reception efficiency is improved. In addition, since it is possible to acquire three-dimensional information for each pixel based on a plurality of light reception information acquired for each pattern, processing from laser irradiation to acquisition of three-dimensional information becomes easy, and an actual traveling vehicle collision It can be used as a prevention device.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a collision prevention device and a vehicle equipped with a collision prevention device according to the present invention will be described in detail with reference to the drawings. In addition, embodiment shown below shows a part of suitable embodiment which concerns on this invention, and this invention is not limited to the following embodiment.

  FIG. 1 is a block diagram showing a schematic configuration of an embodiment according to a collision preventing apparatus and a vehicle of the present invention. The collision prevention apparatus according to the present embodiment includes a three-dimensional information acquisition device (hereinafter referred to as a three-dimensional laser radar) 12 that irradiates and receives laser light, and an obstacle based on information acquired by the three-dimensional laser radar 12. A calculation means (computer) 70 for calculating the distance to the vehicle and outputting various signals, a display device 90 for receiving information from the calculation means 70 and displaying distance information to an obstacle, etc., and the calculation means 70 And a vehicle control device 80 that outputs a signal to the actuator (brake actuator 82, accelerator actuator 84, handle actuator 86) and alarm device 88 provided in the vehicle (moving body) 14 in response to a signal from the vehicle. And And the collision prevention apparatus mounting vehicle 10 which concerns on this invention mounts the collision prevention apparatus which has the said basic structure in the vehicle 14. As shown in FIG. Although not shown, naturally, the vehicle 14 is provided with a drive device and the like for driving the vehicle.

The three-dimensional laser radar 12 includes a laser irradiation unit 20, an optical unit 30, and a radar circuit unit 50. The three-dimensional laser radar 12 measures the state of a traveling road surface in the vehicle traveling direction, the presence or absence of an obstacle, and the distance to the obstacle. It is a device used to do.
The said laser irradiation unit 20 is a unit which irradiates a laser beam with respect to the course located ahead of the advancing direction of a vehicle. Specifically, a laser output unit 24 including a laser oscillator composed of a laser diode, a mirror, and the like, and a driver for operating the laser diode by giving a signal output from the radar circuit unit 50; and the laser output unit 24 And an optical lens 22 for diffusing the laser light output from. In this embodiment, for example, a cylindrical lens may be used as the optical lens in order to diffuse the irradiated laser light in a fan shape.

  The optical unit 30 is a unit that receives laser light that is reflected by a traveling road surface or an obstacle to be irradiated out of the laser light irradiated by the laser irradiation unit 20. Specifically, an optical lens 32, a prism 34, a micromirror array spatial modulator (hereinafter referred to as a spatial modulator) 38, a photodetector (photoelectric converter) 36, etc. are provided, and the reflected light (laser light) that has arrived. This unit receives light. In general, the optical unit 30 used for laser distance measurement is provided with a band-pass filter (not shown) that transmits only the light in the frequency band of the output laser light before the optical lens 32.

  The optical lens 32 collects the laser beam that has passed through the bandpass filter and guides it to the prism 34. The prism 34 changes the path of the incident laser light, guides it to the micromirror of the spatial modulator 38, and guides the laser light properly reflected by the micromirror to the photodetector 36. The spatial modulator 38 has a plurality of micromirrors (reflectors) arranged on a plane. For example, in the micromirror array 38 a arranged as shown in FIG. 2, the laser light guided by the prism 34 is directed in an appropriate direction (photodetector) by tilting the reflecting surface of each micromirror in a predetermined direction (direction). 36 light receiving surface). The spatial modulator 38 is connected to a micromirror control circuit 40 for individually controlling the operation of the micromirror, and the micromirror control circuit 40 is provided with a timing controller 42 for timing for controlling the micromirror. . The timing controller 42 controls the micromirror according to a certain period. When the micromirror of the spatial modulator 38 having such a control unit is turned on by control, the reflective surface is tilted in a predetermined direction, and in a state where the control is not performed (OFF state), the reflective surface Tilt to the opposite side of ON. For this reason, the laser light incident on the micromirror in the OFF state is not reflected in an appropriate direction and is not received by the photodetector.

  The micro mirror array ON / OFF pattern control is selected from a plurality of patterns corresponding to the desired number of pixels (resolution) of the three-dimensional data. The ON / OFF pattern of the micromirror array of this embodiment is set so that 50% or more of the micromirrors are turned on in each pattern in order to efficiently collect the diffused laser light.

  A Hadamard code may be used to control the ON / OFF pattern of the micromirror array. When Hadamard code is used for pattern control, each phase difference signal detected for each pattern detected by a radar circuit unit to be described later is recorded in the computer 70, and the phase difference of reflected light for each pixel is performed by inverse Hadamard transform. Can be derived. Thereby, the distance and height information for each corresponding pixel on the line irradiated with the laser beam can be obtained. For this reason, the arithmetic processing for acquiring the change of the line which irradiated the laser beam as three-dimensional data becomes easy. Therefore, it is possible to speed up a series of processes from scanning of the measurement surface using laser light to acquisition of three-dimensional data. Further, by using a Hadamard code for pattern control of the micromirror array, the light receiving efficiency is improved N / 2 times compared to the case of acquiring three-dimensional data for each point (N indicates resolution). Therefore, the S / N ratio of the received signal is improved, and it is less likely that the signal is buried in noise during processing such as amplification and detection in the radar circuit unit 50, which will be described in detail later.

  In the present embodiment, the micromirror array has a one-dimensional structure (one-row arrangement structure) that matches the resolution of the fan beam in the width direction in accordance with the laser beam to be irradiated as a fan beam. The control pattern is a one-dimensional Hadamard code. Thereby, since the calculation process performed in order to acquire the three-dimensional data of a driving | running road surface becomes only one dimension, speeding-up of three-dimensional data acquisition is accelerated | stimulated. For example, when the resolution in the vehicle width direction is 8, the micromirror array pattern can be eight patterns shown in FIG.

  According to the laser irradiation unit 20 and the optical unit 30 having the above-described structure, the light reflected in the laser light irradiation range is all for each pixel via the optical lens 32 and the prism 34 for each point determined by the resolution. The image is formed on the corresponding micromirror. For example, in the case of FIG. 4, the reflected light of the laser light irradiated to the point A is imaged on the micromirror at the point B. Based on such a principle, when the micromirror array is provided in the spatial modulator 38, the reflected light corresponding to each pixel is reflected to the photodetector by each micromirror. For this reason, a combination of a plurality of patterns allows the photodetector 36 to be incident with laser light having sufficient light intensity to obtain pixel-unit distance data. By using the Hadamard code for the control pattern of the micromirror array, it is possible to easily obtain distance data for each pixel imaged on the micromirror array, so that the processing speed until acquiring the three-dimensional data is increased. improves.

  In addition, by adopting a fan beam as a distance measuring laser, it is not necessary to change the irradiation angle as in the case of a spot laser. For this reason, a mechanism and a control circuit for changing the laser irradiation angle are not required, and the apparatus can be miniaturized. Furthermore, it is also possible to reduce the size and weight of the apparatus by eliminating the need for a rotational drive motor that is required when a polygon mirror or a galvanometer mirror is employed as the spatial modulator.

  The radar circuit unit 50 supplies an output signal to the laser irradiation unit 20 and gives the same signal as the output signal as a reference signal on the light receiving side, and the reference signal and a signal detected by the optical unit 30 This is a unit for extracting the phase difference. Specifically, a high-frequency oscillator (RF) 52, a power splitter 54, an RF amplifier 56, a hybrid 58, a mixer 60 (60a, 60b), and a low-pass filter (LPF) 62 (62a, 62b) and an A / D converter 64.

  The RF oscillator 52 oscillates a basic signal of the laser. The power splitter 54 divides the signal output from the RF oscillator 52 into a signal to be supplied to the laser irradiation unit 20 and a reference signal on the light receiving side, and outputs the same signal in two directions. A signal output as a supply signal to the laser irradiation unit 20 is input to the RF amplifier 56, amplified, and then input to the laser irradiation unit 20.

  On the other hand, the signal output as the reference signal on the light receiving side is input to the 90 ° hybrid 58, and is divided into two signals (0 ° and −90 °) having the same frequency with a phase difference of 90 °, respectively. Is input. In addition to the output signal from the 90 ° hybrid 58, each mixer 60 is configured to receive a light reception signal input by the photodetector 36 via an RF amplifier 66 and a power splitter 68. An intermediate frequency signal (IF (Intermediate Frequency) signal) is output from each mixer 60 to which two signals are input. The IF signal (sum: high frequency and difference: low frequency) output from the mixer 60 passes through the LPF 62. The difference signal that has passed through the LPF 62 is input to the A / D converter 64. In addition to the signal from the LPF 62, the A / D converter 64 receives a control signal for the spatial modulator 38 from the timing controller 42 of the optical unit 30. The two input signals are each converted into a digital signal and output to the computer 70.

  In the computer 70 to which the signal obtained as described above is input, the inverse conversion of the control pattern given to the micromirror array and the calculation of the distance data from the phase difference of the laser beam are performed, and the traveling with the laser beam irradiated The distance and height of obstacles on the road surface are derived.

  Note that a vehicle including a three-dimensional laser radar having the above structure emits laser light from the laser light irradiation unit in a state as shown in FIGS. That is, the laser beam is irradiated toward the traveling road surface obliquely downward at an angle θ from the three-dimensional laser radar mounting position.

で算出される。また、図５（Ｂ）に示すように、走行路面に障害物がある場合には、障害物とレーザ照射位置との距離をＺ_１とした場合、障害物と車両との距離Ｌ_１は、

で算出される。また、距離Ｌ_１における障害物の高さｈ_１は、

で算出される。なお、ｈは地表（走行路面）からレーザ光の照射位置までの高さを表す。 If the distance between the irradiation position of the laser beam calculated by the computer 70 using the TOF and the traveling road surface is Z ₀ , the distance L ₀ between the vehicle and the traveling road is:

Is calculated by Further, as shown in FIG. 5 (B), when the traveling road is an obstacle, if the distance between the obstacle and the laser irradiation position was Z _1, the distance L ₁ between the obstacle and the vehicle,

Is calculated by The height _{h 1} of the obstacle at a distance _{L 1} is

Is calculated by In addition, h represents the height from the ground surface (traveling road surface) to the irradiation position of the laser beam.

  By executing the above-described calculation by the computer 70, it is possible to obtain data (three-dimensional data) of amplitude and phase (distance and height) for each point on the line irradiated with the laser light. The computer 70 that has calculated the distance and height data for each point on the line sends the distance and height data for each point to the display device 90 described later along with the intensity (reflection intensity) of the received laser beam. Output.

  Further, the computer 70 can set a threshold value in advance for each of the reflection intensity of the laser beam (the intensity of the received laser beam), the distance from the obstacle to the traveling speed, and the height of the obstacle. The distance and height for each point calculated in this way, the reflection intensity of the laser beam, and the respective threshold values are compared. As a result of comparison, if it is determined that the value of the calculation result is large with respect to any threshold, signals such as brake and steering are output to the vehicle control device 80 described later.

  The reason why the threshold is set for the distance from the obstacle is to give priority to the operation by the driver. The reason why the threshold is set for the height of the obstacle is that there is no need to take an avoidance measure for an obstacle (for example, a pebble) or the like that the vehicle can get over. Further, the threshold value is provided for the reflection intensity of the laser beam in order to set the avoidance measure for a highly transmissive object such as rain when traveling in rainy weather.

  The display device 90 includes a monitor, and the distance data and height data corresponding to each point on the traveling road surface calculated by the computer 70 as described above, and the reflection intensity of the laser beam as numerical values or three-dimensional images. Then, it is displayed on the monitor in a state where the driver who drives the vehicle can visually recognize (see FIG. 6). The driver can take avoidance measures such as braking and steering by checking the information displayed on the monitor.

  When the acquired data is displayed as a three-dimensional image, as shown in FIG. 6, the three-dimensional image represented in the tomographic state is set to be displayed by sliding sequentially forward according to the traveling speed of the vehicle. Good. Thereby, even when the obstacle enters the blind spot in the laser irradiation range, the distance to the obstacle and the height (size) of the obstacle can be confirmed on the monitor.

  The vehicle control device 80 is based on a control signal from the computer 70, and an actuator 82 provided corresponding to each of a brake (not shown), an accelerator (not shown), a handle (not shown) and the like provided in the vehicle. , 84, 86 output operation signals. The automatic control by the vehicle control device 80 makes it possible to avoid the danger of a collision that the driver does not notice. A signal may be output to the alarm device 88 based on a signal from the computer 70 to issue an alarm. As a result, the driver can be alerted.

  Next, the difference between the laser beam irradiation range in the vehicle 10 equipped with the collision prevention device and the (light reception) field of view of the optical unit 30 is shown in FIG. 7 and the reason will be described. Here, FIG. 7A shows a side view, and FIG. 7B shows a top view. As can be seen from FIG. 7, the visual field of the optical unit 30 and the laser light irradiation range are substantially equal in the width direction. However, the visual field of the optical unit 30 is clearly set wider for the range in the vehicle traveling direction. This is because the field of view is set in a wide range including the laser light irradiation range, so that even if the field of view changes due to the influence of vibration or the like, the reflected laser light can be received. It depends on what you can do. That is, it is technically possible to perfectly match the visual field of the optical unit 30 with the laser light irradiation range, but in this case, if the optical unit's visual field is out of the laser light irradiation range, the laser light is received. It will not be possible. Therefore, in the present embodiment, the field of view of the optical unit is set wide particularly in the range in the height direction (vehicle traveling direction).

Next, with reference to the flowchart shown in FIG. 8, the flow of processing by the collision prevention apparatus according to the present embodiment will be described.
In the vehicle 10 equipped with the collision prevention apparatus having the above-described configuration, first, threshold values are set for the reflection intensity of the laser beam, the distance to the obstacle, and the height of the obstacle for the computer 70 (step 100). Note that the threshold for the distance may be set in detail for each traveling speed of the vehicle.

  The three-dimensional laser radar 12 is activated to drive the vehicle. As a result, the amplitude-modulated laser light is spread in the width direction of the vehicle by the cylindrical lens (optical lens) 22 and applied to the traveling road surface. For this reason, the irradiated laser light illuminates the traveling road surface in a line shape as a fan beam. On the other hand, in the optical unit 30 on the light receiving side, all the area (line) scattered light (reflected light) irradiated with the fan beam is condensed and imaged on the micromirror.

  More specifically, as shown in FIG. 4, point A on the laser light irradiation line forms an image on a micromirror located at point B on the micromirror array. Then, the laser beam reflected from each point is imaged on each of the micromirrors provided in accordance with the set resolution. At this time, the micromirror control circuit 40 receives the trigger signal from the timing controller 42 and performs ON-OFF control of the micromirror with a pattern according to the one-dimensional Hadamard code (step 110).

The laser beam reflected by the micromirror is received by the photodetector 36, mixed with a reference signal via the mixer 60, converted into a digital signal, and recorded in the computer 70 (step 120).
By performing one-dimensional Hadamard inverse transformation on all data relating to the reflected light recorded in the computer 70, the amplitude and phase (distance and height) and the reflection intensity of the laser light are obtained for each point (step 130).

The obtained result is output to the monitor of the display device 90 (step 140), and each data of the distance to the obstacle, the height of the obstacle, and the reflection intensity of the laser beam, and each data predetermined in step 100 are displayed. (Step 150).
As a result of outputting the data to the monitor of the display device 90, if an avoidance action is taken by the driver, the process returns to step 110 to acquire data on the traveling road surface again (step 160).

  On the other hand, if it is determined that there are points where the distance data to the obstacle, the height data of the obstacle, and the reflection intensity of the laser beam obtained in step 130 all exceed the threshold value determined in step 100, the vehicle A signal is output to the control device, an obstacle avoidance measure is taken (step 170), and the process returns to step 110. If there is no data exceeding the threshold value, or if any data does not exceed the threshold value, the process returns to step 110 without taking any avoidance measures.

The above-described control is repeatedly performed at a constant cycle by the timing controller, thereby preventing the vehicle from colliding.
The collision prevention apparatus as described above can improve the processing speed of the three-dimensional data obtained by the three-dimensional laser radar, and thus hinders traveling even when mounted on an actual vehicle. There is no.

For example, when the resolution in the vehicle width direction is 128 and the measurement pitch is 10 cm, the maximum speed that can be measured is about 75 km / h. This is a numerical value that can be derived by the following calculation.
First, it is assumed that a 1024 × 128 DMD (Digital Micromirror Device) array is used. The DMD has a 1-bit SRAM (Static Random Access Memory) for each mirror. By storing 1 or 0 data in this memory, the mirror can be tilted in the direction according to this data. .

となる。 Here, the data signal bit width is 64 bits and the frequency is 120 MHz. In this case, the time required to write 1, 0 data to the SRAM of the assumed DMD array is as follows:

It becomes.

となる。この場合、１秒あたりの計測回数は、約２１１回となる。したがって、計測ピッチを１０ｃｍとすると、最高速度は、２１１０ｃｍ／ｓである。これを時速に換算すると約７５ｋｍ／ｈとなる。 The time required to tilt the mirror according to the data stored in the SRAM is about 20 μsec. Also, since the number of patterns required for a resolution of 128 is 128, the time required to change the micromirror array for all patterns is

It becomes. In this case, the number of measurements per second is about 211 times. Therefore, when the measurement pitch is 10 cm, the maximum speed is 2110 cm / s. When this is converted into hourly speed, it becomes about 75 km / h.

When a multi-channel photodetector is used, the number of pixels in the vehicle width direction detected by one channel is reduced, so that the measurement pitch when traveling at the same speed can be shortened. For example, if the number of channels of the photodetector is 8 and the resolution in the vehicle width direction is 128, the number of pixels detected by one channel is 128/8 = 16. Therefore, the number of one-dimensional Hadamard patterns is better.
In this case, the measurement pitch is 10/8 = 1.25 cm.

In the embodiment, the number of laser beams to be irradiated has been described as one. However, in order to improve the S / N ratio of the received signal, the number of laser beams to be irradiated may be increased. When the number of laser beams to be irradiated is increased in order to improve the S / N ratio of the received signal, it becomes difficult to specify the phase difference of the laser beam at the time of light reception from the difference in the irradiation position of the laser beam. 3D data may not be obtained. In order to prevent this, when a plurality of laser beams are irradiated, it is preferable to superimpose an identification signal for each laser beam. Thereby, it becomes possible to specify the deviation of the irradiation source for each laser beam, and to obtain appropriate three-dimensional data. When the identification signal is superimposed on the laser light, it is necessary to perform demodulation processing by the radar circuit unit 50 or the computer 70 and specify the irradiation source of the incoming laser light. The identification signal may be a PN (Pseudo Noise) signal or the like.
As described above, according to the collision prevention device and the vehicle equipped with the collision prevention device of the present invention, three-dimensional data can be obtained at a practical level of traveling speed.

  In addition, even if it installs in the ship etc. other than a vehicle, for example, the collision prevention apparatus of this invention can be utilized effectively.

1 is a block diagram showing a collision prevention device and a vehicle equipped with a collision prevention device of the present invention. It is a figure which shows the operation state of a micromirror array. It is a figure which shows the ON-OFF pattern of a micromirror when the resolution is set to 8. It is a figure which shows the image of the light-receiving state of a laser beam. It is a figure which shows the principle of ranging of a vehicle, an obstruction, etc. It is a figure which shows the example of the three-dimensional image displayed on the monitor of a display apparatus. It is a figure which shows the difference of the laser beam irradiation range and the reading visual field of an optical unit in the vehicle mounted with the collision prevention apparatus of this invention. It is a flowchart which shows the flow of a process of a collision prevention apparatus.

Explanation of symbols

  10 ......... Vehicle with anti-collision device, 12 ......... 3D laser radar, 14 ......... Vehicle, 20 ......... Laser irradiation unit, 22 ......... Cylindrical lens, 24 ......... Laser output unit, 30 ... ...... Optical unit, 32 .... Optical lens, 34 ........ Prism, 36 .... Photodetector, 38 .... Micromirror spatial modulator, 40 .... Micromirror control circuit, 42 .... Timing Controller 50... Radar circuit unit 52... High frequency oscillator (RF oscillator) 54 54 Power splitter 56 RF amplifier 58 90 hybrid 60 (60a, 60b) ...... Mixer, 62 (62a, 62b) ......... Low-pass filter (LPF), 64 ......... A / D converter, 66 ......... RF amplifier, 68 ......... Power splice 70 ......... Calculation means (computer), 80 ......... Vehicle control device, 82 ......... Brake actuator, 84 ......... Accelerator actuator, 86 ......... Handle actuator, 88 ......... Alarm, 90 ... ...... Display device.

Claims (5)

A three-dimensional information acquisition device for acquiring three-dimensional information of a measurement object using laser light, and a calculation means for outputting a signal to a braking means for a moving body or an alarm provided in the moving body based on the acquired three-dimensional information An anti-collision device comprising:
The three-dimensional information acquisition device includes a laser beam irradiation unit that irradiates a laser beam;
Of the irradiated laser light, an optical unit that receives the laser light that is reflected by the measurement target surface, and
A radar circuit unit that calculates a phase difference between the laser light irradiated from the laser light irradiation unit and the laser light received by the optical unit;
The optical unit includes a spatial modulator that configures the reflecting surface according to a number of different patterns corresponding to the resolution of the three-dimensional information to be acquired and guides the incoming laser light to the light receiving unit,
The collision prevention apparatus, wherein the laser beam irradiation unit includes a lens that diffuses the laser beam to be irradiated.   2. The collision preventing apparatus according to claim 1, wherein a micromirror array is used for the spatial modulator.   The collision prevention apparatus according to claim 2, wherein the micro mirror array forms a reflection surface with at least half or more mirrors in each pattern.   The lens is a cylindrical lens, configured to irradiate a laser beam in a fan shape, the micromirror array is configured to correspond to the fan-shaped laser beam, and the micromirrors are arranged in one row in the moving body width direction. The collision preventing apparatus according to claim 3.   A vehicle equipped with the collision prevention device according to any one of claims 1 to 4, wherein the collision prevention device is mounted.

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