JP2019219291A - Ranging device and ranging method - Google Patents

Abstract

To provide a ranging device which offers high resistance to contamination of a path of light or an electromagnetic wave for ranging, and to provide a ranging device and method, which allow for maintaining ranging accuracy even in the presence of an obstruction(s) in a path of light or an electromagnetic wave for ranging.SOLUTION: A ranging device of the present invention comprises a light-emitter configured to emit first output light in a first direction and second output light in a second direction, and a first deflector configured to deflect the first output light, and is characterized in that a first irradiation area irradiated with the first output light deflected by the first deflector at least partially overlaps with a second irradiation area irradiated with the second output light.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a distance measuring device and a distance measuring method.

  2. Description of the Related Art Conventionally, a distance measuring device that measures a distance to an object using light or electromagnetic waves has been used. For example, Patent Literature 1 discloses a radar device that switches the emission direction of a radar beam using a dielectric lens and performs detection in a plurality of different regions.

JP 2006-145399 A

  For example, in the case of a distance measuring device that measures the distance to an object using light or electromagnetic waves, a light-transmitting resin or other light-transmitting resin for protecting the device is provided in a region where the light for measuring the distance or the electromagnetic waves passes. A member is provided. If such a portion through which light or electromagnetic waves pass is soiled, there is a possibility that the accuracy of distance measurement is reduced or that distance measurement becomes difficult.

  Further, when the distance measuring device is installed in a room of a moving body such as an automobile, and, for example, distance measurement of the outside world is performed through a windshield, the distance measurement accuracy is reduced when the wiper is operated, or the distance measurement becomes difficult. May be lost.

  The present invention has been made in view of the above points, and has as its object to provide, for example, a distance measuring apparatus having high resistance to contamination in a path of light for measuring distance or an electromagnetic wave. An object of the present invention is to provide a distance measuring apparatus and a distance measuring method capable of maintaining distance measuring accuracy even when an obstacle exists on a path of light or electromagnetic waves for distance measuring.

  According to the first aspect of the present invention, a light emitting unit that emits first emission light in a first direction and emits second emission light in a second direction, and deflects the first emission light. A first deflecting unit, a first irradiation region irradiated with the first emission light deflected by the first deflection unit, and a second irradiation region irradiated with the second emission light. A distance measuring apparatus characterized in that at least a part thereof overlaps with each other.

  According to a ninth aspect of the present invention, a light emitting unit that emits first emitted light in a first direction and emits second emitted light in a second direction, and deflects the first emitted light. A distance measuring method for a distance measuring apparatus, comprising: a first deflecting unit; and a control unit that controls the light emitting unit, wherein the control unit causes the light emitting unit to emit the first emitted light. The control unit causes the light emitting unit to emit the second emission light, and the first irradiation region irradiated with the first emission light deflected by the first deflecting unit; The distance measurement method is characterized in that at least a part of a second irradiation area irradiated with the outgoing light overlaps with each other.

1 is a top view of an automobile equipped with a distance measuring device according to a first embodiment. FIG. 2 is a cross-sectional view of the distance measuring device according to the first embodiment. 1 is a side view of an automobile equipped with a distance measuring device according to a first embodiment. FIG. 3 is a functional block diagram of a controller of the distance measuring device according to the first embodiment. FIG. 3 is a diagram illustrating an operation control routine of the distance measuring apparatus according to the first embodiment. It is sectional drawing of the ranging device which concerns on a modification. FIG. 8 is a top view of an automobile equipped with the distance measuring device according to the second embodiment. FIG. 7 is a cross-sectional view of a distance measuring device according to a second embodiment. FIG. 9 is a side view of an automobile equipped with the distance measuring device according to the second embodiment. FIG. 9 is a functional block diagram of a controller of the distance measuring device according to the second embodiment. FIG. 9 is a diagram illustrating an operation control routine of the distance measuring apparatus according to the second embodiment. It is sectional drawing of the ranging device which concerns on a modification. It is a top view of the motor vehicle which mounts the distance measuring device concerning a modification.

  Hereinafter, examples of the present invention will be described in detail. In the following description, a case in which the distance measuring device is mounted on an automobile as an example of a moving object will be described as an example.

[Configuration of distance measuring device]
FIG. 1 is a top view of an automobile M equipped with the distance measuring device 10 according to the first embodiment. In the first embodiment, a case will be described in which the distance measuring device 10 is attached to a front bumper portion of an automobile M. In the following description, the front-back direction of the vehicle M is defined as an X direction, the left-right direction, that is, the width direction is defined as a Y direction, and the up-down direction is defined as a Z direction.

  The distance measuring device 10 is a laser distance measuring device that emits laser light, receives the reflected light of the emitted laser light reflected by an object, and measures the distance. The distance measuring device 10 is mounted on a central portion of a front end of the vehicle M. In other words, the distance measuring device 10 is attached so as to overlap with the center line AX along the front-rear direction of the vehicle M as viewed from above and below. The distance measuring device 10 is configured to emit a laser beam toward an irradiation area LR in front of the vehicle M. FIG. 1 shows, as an example, a case where the irradiation region LR is a region that is line-symmetric with respect to the center line AX when viewed from above the vehicle M.

  FIG. 2 is a cross-sectional view of the distance measuring device 10 in a plane including the center axis AX and the Z axis in FIG. The housing 11 extends in the front-rear direction of the vehicle M, that is, a square bottom 11A having a square cylindrical shape having a cylindrical axis in a direction along the X axis, and a rectangular bottom portion closing one of the openings of the cylindrical portion 11A. 11B. In other words, the housing 11 is a box in which the opening 11C is formed.

  At the center of the inner surface 11S of the bottom 11B of the housing 11, a laser emission light receiving device 13 is provided as a light emission unit capable of emitting a pulse laser in a direction variable toward the opening 11C. The laser emission light receiving device 13 includes, for example, a laser element (not shown) that emits laser light and a MEMS mirror (not shown) that variably reflects the laser light. The laser emitting light receiving device 13 as a light receiving unit has a light receiving element (not shown) that can detect the emitted laser light by receiving the reflected light reflected by the object. For example, the laser emission light receiving device 13 is a so-called laser LiDER device.

  The laser emission light-receiving device 13 can emit the first emission light EL1 to the first emission region ER1 in the first direction range when viewed from the laser emission light-receiving device 13. In addition, the laser emission light receiving device 13 can emit the second emission light EL2 to the second emission region ER2 in the second direction range when viewed from the laser emission light receiving device 13. In other words, the laser emission light receiving device 13 can emit the first emission light EL1 in the first direction within the first direction range, and can emit the second emission light EL1 in the second direction within the second direction range. The emitted light EL2 can be emitted. The laser emission light-receiving device 13 can scan the pulse laser toward the first emission region ER1 and the second emission region ER2.

  Note that the scanning mode of the pulse laser may be, for example, raster scanning or Lissajous scanning. That is, the entire first emission region ER1 and the entire second emission region ER2 may be sequentially scanned by raster scanning. Further, the entire first emission region ER1 and second emission region ER2 may be scanned at once by Lissajous scanning.

  The protection plate 15 is a plate-shaped translucent member such as a resin material or a glass material provided to cover the opening 11C. The translucent member used for the protection plate 15 is a member that transmits the light of the wavelengths of the emission lights EL1 and EL2 emitted from the laser emission light receiving device 13.

  The emitted light emitted from the laser emitting and receiving device 13 passes through the protective plate 15 and goes out of the distance measuring device 10 to the outside. The reflected light received by the laser emitting / receiving device 13 passes through the protective plate 15 and reaches the laser emitting / receiving device 13 from outside. The protection plate 15 has a function of transmitting the light emitted from the laser emitting / receiving device 13 and the reflected light to the laser emitting / receiving device 13 and preventing foreign matter from entering the distance measuring device 10. It should be noted that a removing device that removes foreign matter adhering to the surface 15S of the protective plate 15 may be provided. For example, a wiper device (not shown) operable along the surface 15S of the protection plate 15 may be provided.

  In the first embodiment, the case where the protection plate 15 is flat is described as an example. However, the protection plate 15 is, for example, convex toward the outside of the housing 10, that is, the emitted lights EL 1 and EL 2 of the laser emission light receiving device 13. May be a dome shape having a shape that is convex toward the emission direction.

  The deflecting plate 17 is a light-transmitting member made of a plate-like resin material or a glass material provided between the protection plate 15 inside the housing 11 and the laser emission light receiving device 13. The translucent member used for the deflecting plate is a member that transmits the light having the wavelengths of the emission lights EL1 and EL2 emitted from the laser emission light receiving device 13. That is, the light emitted from the laser emission light receiving device 13 passes through the deflection plate 17 and the protection plate 15 in this order, and goes out of the distance measuring device 10 to the outside. The reflected light received by the laser emitting / receiving device 13 passes through the protective plate 15 and the deflecting plate 17 in this order and reaches the laser emitting / receiving device 13 from outside.

  A first deflecting portion 17A is formed in a portion of the deflecting plate 17 through which the first emission light EL1 passes. The first deflecting unit 17A is a part having the function of a transmission type deflecting element that deflects the first emission light EL1 downward while transmitting the first emission light EL1. The first deflecting unit 17A may be, for example, a diffraction grating, a Fresnel lens, a hologram, or a dielectric lens.

  A second deflecting portion 17B is formed in a portion of the deflecting plate 17 through which the second emission light EL2 passes. The second deflecting unit 17B is a portion having a function of a transmission type deflecting element that transmits the second emission light EL2 and deflects the light upward. The second deflecting unit 17B may be, for example, a diffraction grating, a Fresnel lens, a hologram, or a dielectric lens.

  The first emission light EL1 is deflected downward when passing through the first deflecting unit 17A, and becomes the first irradiation light LL1 irradiated to the first irradiation region LR1. In other words, the first irradiation area LR1 is an area irradiated with the first emission light EL1 deflected by the first deflecting unit 17A.

  Further, the second emission light EL2 is deflected downward when passing through the second deflecting unit 17B, and becomes the second irradiation light LL2 irradiated to the second irradiation region LR2. In other words, the second irradiation area LR2 is an area irradiated with the second emission light EL2 deflected by the second deflecting unit 17B.

  As described above, the first deflecting unit 17A and the second deflecting unit 17B are formed in predetermined regions of the deflecting plate 17, respectively. In other words, the first deflecting unit 17A and the second deflecting unit 17B are held by the deflecting plate 17, and the deflecting plate 17 is a holding member of the first deflecting unit 17A and the second deflecting unit 17B. .

  The first deflecting unit 17A and the second deflecting unit 17B need not be formed in the deflecting plate 17. That is, the first deflecting unit 17A and the second deflecting unit 17B are formed separately from the deflecting plate 17, and the deflecting plate 17 holds the separate first deflecting unit 17A and the second deflecting unit 17B. You may do it.

  In this case, a hole is formed in the deflecting plate 17 at a position where the first deflecting unit 17A and the second deflecting unit 17B exist in FIG. 2, and a member forming the deflecting units 17A and 17B is fitted into the hole. Thus, the deflection plate 17 may hold them. Further, a member forming the deflecting portions 17A and 17B may be fixed to the surface of the deflecting plate 17 by bonding or the like, and the deflecting plate 17 may hold the deflecting portions 17A and 17B.

  It should be noted that portions other than the first deflecting portion 17A and the second deflecting portion 17B of the deflecting plate 17 do not need to have translucency because the outgoing lights EL1 and EL2 do not reach. Further, the first deflecting unit 17A and the second deflecting unit 17B may not be formed in the deflecting plate 17, and are respectively held on the optical path of the first outgoing light and the optical path of the second outgoing light. It would be fine. Therefore, the first deflecting unit 17A and the second deflecting unit 17B are formed by separate members, and are not held by the deflecting plate 17, but are held by another holding member fixed to the housing 11. You may do it.

  2, the center line CX1 of the first irradiation region LR1 and the center line CX2 of the second irradiation region LR2 are parallel to each other. That is, the first irradiation light LL1 and the second irradiation light LL2 are light beams irradiated in the same direction.

  Further, the first irradiation light LL1 and the second irradiation light LL2 are radiated to the outside through another part of the protection plate 15. That is, when transmitting through the protection plate 15, the first irradiation light LL1 and the second irradiation light LL2 are transmitted through different paths.

  FIG. 3 is a side view of the automobile M on which the distance measuring device 10 is mounted. FIG. 3 shows an enlarged front end portion of the vehicle M. In FIG. 3, the first irradiation light LL1 is indicated by a two-dot chain line, and the second irradiation light LL2 is indicated by a broken line.

  As shown in FIG. 3, the first irradiation light LL1 and the second irradiation light LL2 are applied to a slightly shifted but substantially overlapping region. That is, the first irradiation light LL1 and the second irradiation light LL2 irradiate substantially the same region. In other words, the first irradiation region LR1 and the second irradiation region LR2 at least partially overlap each other.

  As described above with reference to FIG. 2, the irradiation lights LL1 and LL2 exit from the opening 11A of the distance measuring apparatus (see FIG. 2) through different paths through different portions of the protective plate 15, but are macroscopic. According to the above, the light is irradiated on the area which is slightly shifted but is irradiated on the substantially same area. That is, the emitted lights EL1 and EL2 emitted in two different direction ranges are the emitted lights LL1 and LL2 applied to substantially the same area.

  In the distance measuring device 10, the irradiation lights LL1 and LL2 pass through different paths from the distance measuring device 10, specifically, pass through different portions of the protective plate 15, and are emitted almost outside the distance measuring device 10. It is configured to irradiate the same area. In other words, the distance measuring device 10 has a redundant configuration in which a plurality of irradiation light beams irradiating the same region by one laser emission light receiving device 13 can be measured by the plurality of irradiation light beams in the same region. ing.

  Therefore, even if the protection plate 15 of the distance measuring device 10 is partially soiled, accurate distance measurement can be performed. Specifically, even if a portion through which one of the irradiation lights LL1 or LL2 is contaminated, accurate distance measurement can be performed by measuring the distance using the other irradiation light.

[Controller configuration]
FIG. 4 is a diagram showing a configuration of the controller 20 which has a function of controlling light emission of the laser emission light receiving device 13 of the distance measuring device 10 and a distance measuring function. The controller 20 may be provided, for example, separately from the laser emission light receiving device 13 and may be communicably connected to the laser emission light receiving device 13. Further, the controller 20 may be provided in, for example, the laser emission light receiving device 13. In the following description, an example in which the controller 20 is provided separately from the laser emission light receiving device 13 will be described.

  The controller 20 is, for example, a device in which the mass storage device 23, the control unit 25, and the input / output unit 27 cooperate via the system bus 21.

  The large-capacity storage device 23 includes, for example, a hard disk device, an SSD (solid state drive), a flash memory, and the like, and stores an operating system and various programs such as terminal software. The various programs may be acquired from another server device or the like via a network, or may be recorded on a recording medium and read via various drive devices.

  That is, various programs stored in the large-capacity storage device 23 (including a program for controlling the laser emitting / receiving device 13 described below and executing a process for distance measurement) can be transmitted via a network. It is also possible to record and transfer the data on a computer-readable recording medium.

  The control unit 25 includes a CPU (Central Processing Unit) 25A, a ROM (Read Only Memory) 25B, a RAM (Random Access Memory) 25C, and functions as a computer. Then, the CPU 25A realizes various functions by reading and executing various programs stored in the ROM 25B and the large-capacity storage device 23.

  The input / output unit 27 is a functional part that performs information communication with the laser emitting / receiving device 13. The input / output unit 27 can transmit a control signal for controlling the operation of the laser emitting / receiving device 13 to the laser emitting / receiving device 13. Further, the input / output unit 27 can receive a light receiving signal, which is a signal when the laser emission light receiving device 13 receives the reflected light, from the laser emission light receiving device 13.

  The control unit 25 can calculate the distance between the object that has reflected the irradiation lights LL1 and LL2 and the distance measuring device 10 or the car M based on the received signal. For example, the control unit 25 can calculate the distance using a TOF (Time Of Flight) method or a phase difference method.

  The input / output unit 27 may be capable of communicating information with another device. For example, it may be possible to receive, from an external device, information indicating whether the distance measurement operation is currently required. The control unit 25 generates a control signal for controlling the laser emitting / receiving device 13 in accordance with the information indicating whether the distance measurement operation is required, and transmits the control signal to the laser via the input / output unit 27. It may be transmitted to the emission light receiving device 13.

  Note that, for example, the distance measuring device 10 may be provided with a removing device such as a wiper that can remove foreign matter attached to the surface 15S of the protective plate 15. That is, the distance measuring apparatus 10 may be provided with a removing unit that removes an obstacle on the optical path of the first irradiation term and the second irradiation light. In that case, the input / output unit 27 may be capable of communicating information with the removal device.

  For example, when the control unit 25 detects the presence of a foreign substance on the surface 15S of the protection plate 15, the control unit 25 generates a control signal for causing the removing device to perform the removing operation of the foreign substance. It may be possible to transmit the control signal to the removing device via the control device.

  The detection of foreign matter on the surface 15S of the protection plate 15 may be performed based on a light receiving signal which is a signal when the laser emission light receiving device 13 receives the reflected light. For example, when a distance measurement process is performed based on a light receiving signal and an object that is closer than a threshold is detected, a foreign object may be determined to be present on the surface 15S of the protection plate 15.

[Ranging operation control routine]
In the following, a description will be given of a ranging operation control routine executed by the control unit 25 in order to realize a redundant ranging operation of the ranging apparatus 10 of the first embodiment.

  FIG. 5 is a flowchart of an operation control routine R1 which is an example of the distance measurement operation control routine. For example, the operation control routine R1 is started when power is supplied to the distance measuring device 10, and is repeatedly executed. The operation control routine R1 may be started when the ACC power supply of the vehicle equipped with the distance measuring device 10 is turned on.

  In the operation control routine R1, the distance measurement is normally performed using both the irradiation lights LL1 and LL2. If a foreign substance adheres to the surface 15S of the protective plate 15 during the distance measurement using both the irradiation lights LL1 and LL2, the irradiation light that passes through the area of the irradiation lights LL1 and LL2 to which the foreign substance adheres is used. Cancels the used distance measurement. That is, the distance measurement is continued using only the irradiation light in which no foreign matter exists in the irradiation path.

  When the operation control routine R1 is started, the control unit 25 first determines whether or not a ranging operation is required in the vehicle M in step S11. This determination may be made, for example, based on whether the vehicle M is in the automatic driving state. Specifically, information on whether the vehicle M is currently under the automatic driving control or the manual driving control is acquired, and when the vehicle M is under the automatic driving control, it is determined that the ranging operation is required. May be.

  The determination as to whether or not the ranging operation is required may be made by determining whether or not a passenger has performed a ranging operation in the automobile M. The determination as to whether or not the distance measurement operation is required may be made based on the traveling speed of the vehicle M or the current traveling position of the vehicle M.

  If it is determined in step S11 that the distance measurement operation is not required (step S11: NO), the operation control routine R1 is executed again from the beginning. In step S11, when it is determined that the distance measurement operation is required (step S11: YES), the control unit 25 causes the laser emission light receiving device 13 to emit the emission lights EL1 and EL2 and perform scanning. The distance measurement in the normal scanning mode is started (step S12). In the normal scanning mode, raster scanning may be performed to scan the irradiation areas LR1 and LR2 alternately with the irradiation light LL1 and the irradiation light LL2. That is, the control unit 25 causes the laser emission light receiving device 13 as the light emission unit to emit the first emission light EL and the second emission light EL2.

  After execution of step S12, the control unit 25 determines in step S13 whether or not the ranging operation is required in the vehicle M again. This determination can be made in the same manner as the determination in step S111. If it is determined in step S13 that the distance measurement operation is not required (step S13: NO), the control unit 25 causes the laser emission light receiving device 13 to stop emitting the emission lights EL1 and EL2, and performs distance measurement. The operation ends (step S14). After the end of step S14, the operation control routine R1 is executed again from the beginning.

  If it is determined in step S13 that the distance measurement operation is still required (step S13: YES), the control unit 25 determines that there is a foreign substance on the surface 15S of the protection plate 15 on the path of the irradiation lights LL1 and LL2. It is determined whether or not it has been performed (step S15). This determination can be made by detecting the foreign matter based on a light receiving signal from the laser emission light receiving device 13. Specifically, for example, in the distance measurement using either the irradiation light LL1 or LL2, when an object at a distance closer than a predetermined threshold is detected, it is determined that a foreign substance exists on the surface 15S of the protection plate 15. May be.

  If it is determined in step S15 that there is no foreign object (step S15: NO), the control unit 25 executes step S13 again to determine whether the distance measurement operation is still required.

  If it is determined in step S15 that a foreign substance is present (step S15: YES), the control unit 25 measures the distance by using the irradiation light including the region where the foreign substance exists among the irradiation lights LL1 and LL2 in the path. Is stopped, and the mode shifts to the single scanning mode, which is a mode in which the distance is measured only by the irradiation light having no foreign matter on the path (step S16).

  In this single scanning mode, the laser emission light receiving device 13 may emit only one of the emission light EL1 and EL2. That is, of the irradiation lights LL1 and LL2, only the emission light serving as the irradiation light used for the distance measurement may be emitted to the laser emission light receiving device 13. Further, in the single scanning mode, both the emission lights EL1 and EL2 may be emitted from the laser emission light receiving device 13, and only one of the irradiation lights LL1 and LL2 may be used for distance measurement.

  After step S16 is executed, the control unit 25 determines again whether or not the ranging operation is required in the vehicle M in step S17. This determination can be made in the same manner as the determination in step S11. If it is determined in step S17 that the distance measurement operation is not required (step S17: NO), the control unit 25 causes the laser emission light receiving device 13 to stop emitting the emission lights EL1 and EL2, and performs distance measurement. The operation ends (step S14). After the end of step S14, the operation control routine R1 is executed again from the beginning.

  If it is determined in step S17 that the distance measurement operation is still required (step S17: YES), the control unit 25 determines whether the foreign matter detected in step S15 remains (step S15). Step S18). This determination can be made by detecting the foreign matter based on a light receiving signal from the laser emission light receiving device 13. Specifically, for example, when distance measurement is attempted using irradiation light that is not used in the single scanning mode, and an object that is closer than a predetermined threshold is detected, the object is detected on the surface 15S of the protection plate 15. It may be determined that foreign matter remains.

  If it is determined in step S18 that the foreign matter remains (step S18: YES), the control unit 25 executes step S17 again. That is, the distance measurement in the single scanning mode is continued.

  If it is determined in step S18 that no foreign matter remains (step S18: NO), the control unit 25 returns to the normal scanning mode for performing distance measurement using both the irradiation lights LL1 and LL2, and performs distance measurement. Is continued (step S19).

  In the case where the distance measuring device 10 is provided with a removing device such as a wiper capable of removing the foreign matter attached to the surface 15S of the protective plate 15, the foreign material is removed during the distance measuring in the single scanning mode. May be performed.

  As described above, in the distance measuring device 10, the irradiation lights LL1 and LL2 generated by the emitted lights EL1 and EL2 from the one laser emitting and receiving device 13 pass through different paths from the distance measuring device 10, and specifically, Has a configuration in which light is transmitted through different portions of the protective plate 15 and emitted to substantially the same region outside the distance measuring device 10. That is, the distance measuring device 10 has a redundant configuration in which the same area can be measured by the irradiation lights LL1 and LL2.

  When the operation control routine R1 is executed in the distance measuring apparatus 10 having the above-described configuration, accurate distance measurement can be continuously performed even if the protective plate 15 of the distance measuring apparatus 10 is partially soiled. Specifically, even if a portion through which one of the irradiation lights LL1 or LL2 passes is soiled, accurate distance measurement can be continued by measuring the distance using the other irradiation light.

  In the above description, the case where the two deflecting units of the deflecting units 17A and 17B are formed on the deflecting plate 17 has been described as an example, but the number of deflecting units may be one. For example, as shown in FIG. 6, only the deflection unit 17A may be formed, and only ER1 may be deflected. Also in this case, if the emission light EL1 is deflected so that the central axes CX1 and CX2 of the irradiation light LL1 and LL2 that have passed through the deflecting plate 17 become parallel, the irradiation light LL1 and the light LL1 are converted in the same manner as in the distance measuring device described above. The irradiation light LL2 is applied to almost the same area.

  Hereinafter, the distance measuring device 30 according to the second embodiment of the present invention will be described.

[Configuration of distance measuring device]
FIG. 7 is a top view of an automobile M equipped with the distance measuring device 30 according to the second embodiment. In the second embodiment, a case will be described in which the distance measuring device 30 is mounted inside the windshield FG of the automobile M. In the following description, the front-back direction of the vehicle M is defined as an X direction, the left-right direction, that is, the width direction is defined as a Y direction, and the up-down direction is defined as a Z direction.

  Similarly to the distance measuring apparatus 10 according to the first embodiment, the distance measuring apparatus 30 emits a laser beam, receives the reflected light of the emitted laser light reflected by an object, and measures the distance. It is. The distance measuring device 30 is mounted on a central portion inside the windshield FG of the automobile M. In other words, the distance measuring device 30 is attached so as to overlap the center line AX along the front-rear direction of the vehicle M when viewed from above and below.

  The distance measuring device 30 is configured to emit a laser beam toward an irradiation region LR in front of the vehicle M. FIG. 7 shows, as an example, a case where the irradiation region LR is a region that is line-symmetric with respect to the center line AX when viewed from above the vehicle M.

  FIG. 8 is a cross-sectional view of the distance measuring device 30 in a plane including the central axes AX and Z axes in FIG. The vehicle M is provided with a wiper device WP capable of removing foreign matter on the outer surface OS of the windshield FG.

  The casing 31 extends in the up-down direction of the automobile M, that is, a square bottom 31A having a square cylindrical shape having a cylindrical axis in a direction along the Z axis and a rectangular bottom portion closing one of the openings of the cylindrical portion 11A. 31B. In other words, the housing 31 is a box in which the opening 31C is formed.

  An opening end 31E as an opening end forming the opening 31C of the housing 31 has a shape along the inner surface IS of the windshield FG. That is, the open end 31E has an inclined shape that goes downward as it goes forward of the vehicle M. In the embodiment, the opening end 31E is covered with a windshield FG.

  At the center of the inner surface S31 of the bottom 31B of the housing 31, there is provided a laser emitting / receiving device 33 capable of emitting a pulse laser in a direction variable to the opening 31C. The laser emission light receiving device 33 is the same device as the laser emission light receiving device 13 of the first embodiment, and includes, for example, a laser element that emits laser light and a MEMS mirror that reflects the laser light in a variable direction. Further, the laser emission light receiving device 33 as a light receiving portion has a light receiving element capable of detecting the emitted laser light by receiving the reflected light reflected by the object. For example, the laser emission light receiving device 33 is a so-called laser LiDER device.

  The laser emission light receiving device 33 can emit the first emission light EL1 to the first emission region ER1 in the first direction range when viewed from the laser emission light receiving device 33. In addition, the laser emission light receiving device 31 can emit the second emission light EL2 to the second emission region ER2 in the second direction range when viewed from the laser emission light reception device 33. The laser emission light receiving device 33 can scan the pulse laser toward the first emission region ER1 and the second emission region ER2.

  Note that the scanning mode of the pulse laser may be, for example, raster scanning or Lissajous scanning. That is, the entire first emission region ER1 and the entire second emission region ER2 may be sequentially scanned by raster scanning. Further, the entire first emission region ER1 and second emission region ER2 may be scanned collectively by Lissajous scanning.

  The deflecting plate 35 is a light-transmitting member made of a plate-shaped resin material or a glass material provided at the opening end 31 </ b> E of the housing 31. The translucent member used for the deflecting plate is a member that transmits the emitted light EL1 and EL2 emitted from the laser emission light receiving device 33. That is, the light emitted from the laser emission light receiving device 33 passes through the deflection plate 35 and goes out of the distance measuring device 30 to the outside. The reflected light received by the laser emitting / receiving device 33 passes through the deflection plate 35 and reaches the laser emitting / receiving device 33 from outside.

  A first deflecting section 35A is formed in a portion of the deflecting plate 35 through which the first emission light EL1 passes. The first deflecting unit 35A is a part having a function of a transmission type deflecting element that transmits the first emission light EL1 and deflects the light forward. The first deflection unit 35A may be, for example, a diffraction grating, a Fresnel lens, a hologram, or a dielectric lens.

  A second deflecting portion 35B is formed in a portion of the deflecting plate 35 through which the second emission light EL2 passes. The second deflecting unit 35B is a part having a function of a transmission type deflection element that deflects the second emission light EL2 forward while transmitting the second emission light EL2. The second deflecting unit 35B may be, for example, a diffraction grating, a Fresnel lens, a hologram, or a dielectric lens.

  The first emission light EL1 is deflected forward when passing through the first deflecting unit 35A, and becomes the first irradiation light LL1 applied to the first irradiation region LR1. Further, the second emission light EL2 is deflected forward when passing through the second deflecting unit 35B, and becomes the second irradiation light LL2 applied to the second irradiation region LR2.

  8, the center line CX1 of the first irradiation region LR1 and the center line CX2 of the second irradiation region LR2 are parallel to each other. That is, the first irradiation light LL1 and the second irradiation light LL2 are light beams irradiated in the same direction.

  Further, the first irradiation light LL1 and the second irradiation light LL2 are radiated to the outside through another part of the windshield FG. That is, when transmitting the front glass FG, the first irradiation light LL1 and the second irradiation light LL2 are transmitted through different paths.

  FIG. 9 is a side view of an automobile M on which the distance measuring device 30 is mounted. FIG. 9 is an enlarged view of the vicinity of the front portion including the windshield FG of the vehicle M. In FIG. 9, the first irradiation light LL1 is indicated by a two-dot chain line, and the second irradiation light LL2 is indicated by a broken line.

  As shown in FIG. 9, the first irradiation light LL1 and the second irradiation light LL2 irradiate a slightly shifted but substantially overlapping region. That is, the first irradiation light LL1 and the second irradiation light LL2 irradiate substantially the same region.

  As described above with reference to FIG. 8, the irradiation lights LL1 and LL2 exit from the opening 11A (see FIG. 2) of the distance measuring device through different paths through different portions of the windshield FG. According to the above, the light is irradiated on the area which is slightly shifted but is irradiated on the substantially same area. That is, the emitted lights EL1 and EL2 emitted in two different direction ranges are the emitted lights LL1 and LL2 applied to substantially the same area.

  In the distance measuring device 30, the irradiation lights LL 1 and LL 2 pass through different paths from the distance measuring device 30, specifically, pass through different portions of the windshield FG, and are emitted almost outside the distance measuring device 30. It is configured to irradiate the same area. That is, the distance measuring device 30 has a redundant configuration in which the same area can be measured by the irradiation lights LL1 and LL2. Therefore, even if the windshield FG of the distance measuring device 30 is partially contaminated, accurate distance measurement can be performed. Specifically, even if a portion through which one of the irradiation lights LL1 or LL2 is contaminated, accurate distance measurement can be performed by measuring the distance using the other irradiation light.

  The distance measuring device 30 has an opening end 31E having a shape along the inner surface IS of the windshield FG. Thereby, it is possible to install the distance measuring device compactly, for example, on a dashboard and close to or very close to the windshield FG. The distance measuring device may be partially or entirely buried in the dashboard, that is, may be buried in the dashboard.

  The opening end 31E of the distance measuring device 30 may be in close contact with the inner surface IS of the windshield FG. The opening end 31E of the distance measuring device 30 may be separated from the inner surface IS of the windshield FG. When the opening end 31E and the inner surface IS of the windshield FG are separated from each other, a sealing material may be filled in the portion.

[Controller configuration]
FIG. 10 is a diagram showing a configuration of a controller 40 which has a function of controlling light emission of the laser emission light receiving device 33 of the distance measuring device 30 and a distance measuring function. The controller 40 may be provided separately from, for example, the laser emission / light reception device 33 and may be communicably connected to the laser emission / light reception device 33. Further, the controller 40 may be provided in, for example, the laser emission light receiving device 33. In the following description, a case in which the controller 40 is provided separately from the laser emission light receiving device 33 will be described as an example.

  Further, the controller 40 may be communicably connected to a driving unit WPA that drives the wiper WP. Specifically, the wiper device may be driven by a signal from the controller 40. Further, the controller 40 may be able to detect whether or not the wiper device is operating.

  The controller 40 is, for example, a device in which the mass storage device 43, the control unit 45, and the input / output unit 47 cooperate via the system bus 41.

  The large-capacity storage device 43 includes, for example, a hard disk device, a solid state drive (SSD), a flash memory, and the like, and stores an operating system and various programs such as terminal software. Note that the various programs may be obtained from another server device or the like via a network, or may be recorded on a recording medium and read via various drive devices.

  In other words, various programs stored in the large-capacity storage device 43 (including a program for controlling the laser emitting / receiving device 33 described below and executing a process for distance measurement) can be transmitted via a network. It is also possible to record and transfer the data on a computer-readable recording medium.

  The control unit 45 includes a CPU (Central Processing Unit) 45A, a ROM (Read Only Memory) 45B, a RAM (Random Access Memory) 45C, and functions as a computer. The CPU 45A implements various functions by reading and executing various programs stored in the ROM 45B and the large-capacity storage device 43.

  The input / output unit 47 is a functional part that performs information communication with the laser emitting / receiving device 43. The input / output unit 47 can transmit a control signal for controlling the operation of the laser emitting / receiving device 33 to the laser emitting / receiving device 33. In addition, the input / output unit 47 can receive a light receiving signal, which is a signal when the laser emitting / receiving device 33 receives the reflected light, from the laser emitting / receiving device 33.

  The control unit 45 can calculate the distance between the object that has reflected the irradiation lights LL1 and LL2 and the distance measuring device 30 or the car M based on the received signal. For example, the control unit 45 can calculate the distance using a TOF (Time Of Flight) method or a phase difference method.

  The input / output unit 47 may be capable of communicating information with other devices. For example, it may be possible to receive, from an external device, information indicating whether the distance measurement operation is currently required. The control unit 45 generates a control signal for controlling the laser emitting / receiving device 33 according to the information on whether the distance measurement operation is required, and outputs the control signal to the laser via the input / output unit 47. It may be transmitted to the emission light receiving device 33.

  Further, the input / output unit 47 may be capable of communicating information with a wiper driving unit WPA that is a driving unit of the wiper WP as the removing device. For example, when the control unit 45 detects that a foreign substance is present on the outer surface OS of the windshield FG, the control unit 45 generates a control signal that causes the removing device to perform the foreign substance removing operation, The control signal may be transmitted to the wiper driving unit WPA via the control unit.

  The detection of foreign matter on the outer surface OS of the windshield FG may be performed based on a light receiving signal which is a signal when the laser emission light receiving device 33 receives reflected light. For example, when a distance measurement process is performed based on a light receiving signal and an object close to a threshold value or more is detected, it may be determined that a foreign object is present on the outer surface OS of the windshield FG.

[Ranging operation control routine]
In the following, a description will be given of a ranging operation control routine executed by the control unit 45 in order to realize a redundant and accurate ranging operation of the ranging apparatus 30 of the first embodiment.

  FIG. 11 is a flowchart of an operation control routine R2 which is an example of the distance measurement operation control routine. For example, the operation control routine R2 is started when power is supplied to the distance measuring device 30, and is repeatedly executed. The operation control routine R2 may be started when the ACC power supply of the vehicle equipped with the distance measuring device 30 is turned on.

  In the operation control routine R2, the distance measurement is normally performed using both the irradiation lights LL1 and LL2. Then, when the wiper WP operates during the distance measurement using both the irradiation lights LL1 and LL2, the distance measurement using the irradiation light passing through the area of the irradiation light LL1 and LL2 through which the wiper WP is passing. To stop. That is, the distance measurement is continued using only the irradiation light in which the wiper WP does not exist in the irradiation path.

  When the operation control routine R2 is started, the control unit 45 first determines whether or not the ranging operation is required in the vehicle M in step S21. This determination may be made, for example, based on whether the vehicle M is in the automatic driving state. Specifically, information on whether the vehicle M is currently under the automatic driving control or the manual driving control is acquired, and when the vehicle M is under the automatic driving control, it is determined that the ranging operation is required. May be.

  The determination as to whether or not the ranging operation is required may be made by determining whether or not a passenger has performed a ranging operation in the automobile M. The determination as to whether or not the distance measurement operation is required may be made based on the traveling speed of the vehicle M or the current traveling position of the vehicle M.

  If it is determined in step S21 that the distance measurement operation is not required (step S21: NO), the operation control routine R1 is executed again from the beginning. When it is determined in step S21 that the distance measurement operation is required (step S21: YES), the control unit 45 causes the laser emission light receiving device 33 to emit the emission lights EL1 and EL2 and perform scanning. The distance measurement in the normal scanning mode is started (step S22). In the normal scanning mode, raster scanning may be performed to scan the irradiation areas LR1 and LR2 alternately with the irradiation light LL1 and the irradiation light LL2.

  After execution of step S22, the control unit 45 determines in step S23 whether or not the ranging operation is required in the vehicle M again. This determination can be made in the same manner as the determination in step S21. If it is determined in step S23 that the distance measurement operation is not required (step S23: NO), the control unit 45 causes the laser emission light receiving device 33 to stop emitting the emission lights EL1 and EL2, and performs distance measurement. The operation ends (step S24). After the end of step S24, the operation control routine R1 is executed again from the beginning.

  If it is determined in step S23 that the ranging operation is still required (step S23: YES), the control unit 45 determines whether the wiper WP is operating (step S25). This determination can be made by detecting the wiper based on a light receiving signal from the laser emission light receiving device 33. Specifically, for example, in distance measurement using either the irradiation light LL1 or LL2, even when it is determined that the wiper WP is operating when an object at a distance closer than a predetermined threshold is detected. Good.

  Since the wiper driving unit WPA and the controller 40 are communicably connected as described above, whether or not the wiper WP is operating may be determined based on a signal from the wiper driving unit WPA.

  If it is determined in step S25 that the wiper WP is not operating (step S25: NO), the control unit 45 executes step S13 again to determine whether the distance measurement operation is still required. .

  In step S25, when it is determined that the wiper WP is operating (step S25: YES), the control unit 45 measures the irradiation light LL1 and LL2 using the irradiation light including the area where the wiper passes in the path. The distance is stopped, and a transition is made to a wiper scanning mode, which is a mode in which the distance is measured only by irradiation light having no foreign matter on the path (step S26).

  In the wiper scanning mode, the laser emission light receiving device 33 may emit only the emission light EL1 or EL2 according to the current position of the wiper WP. That is, of the irradiation lights LL1 and LL2, only the emission light serving as the irradiation light used for distance measurement may be emitted to the laser emission light receiving device 33. In the wiper scanning mode, the laser emission light receiving device 33 emits both the emission lights EL1 and EL2, and the distance measurement is performed by measuring the reflected light of the irradiation light LL1 and LL2, of which the wiper WP does not exist on the path. Only one may be used.

  After step S26 is executed, the control unit 45 determines in step S27 whether or not the ranging operation is required in the vehicle M again. This determination can be made in the same manner as the determination in step S21. If it is determined in step S27 that the distance measurement operation is not required (step S27: NO), the control unit 45 causes the laser emission light receiving device 33 to stop emitting the emission lights EL1 and EL2, and performs distance measurement. The operation ends (step S24). After the end of step S24, the operation control routine R2 is executed again from the beginning.

  If it is determined in step S27 that the distance measurement operation is still required (step S27: YES), control unit 45 determines whether or not wiper WP is still operating (step S28). This determination can be made in the same manner as the determination in step S25.

  If it is determined in step S28 that the wiper WP is still operating (step S28: YES), the control unit 45 executes step S27 again. That is, the distance measurement in the wiper scanning mode is continued.

  If it is determined in step S28 that the operation of the wiper WP has stopped (step S28: NO), the control unit 45 returns to the normal scanning mode for performing distance measurement using both the irradiation lights LL1 and LL2. To continue the distance measurement (step S29).

  As described above, in the distance measuring device 30, the irradiation light LL1 and the light LL2 travel through different paths from the distance measuring device 30, specifically, pass through different portions of the windshield FG, and exit. It is configured to irradiate substantially the same area outside the device 30. That is, the distance measuring device 30 has a redundant configuration in which the same area can be measured by the irradiation lights LL1 and LL2.

  By executing the operation control routine R2 in the distance measuring apparatus 30 having the above configuration, it is possible to continue accurate distance measurement even when the wiper WP is operating in the vehicle M. Specifically, even when the wiper WP exists in a portion through which one of the irradiation lights LL1 and LL2 is transmitted, accurate distance measurement can be continued by measuring the distance using the other irradiation light. It is possible.

  In the above description, the case where the windshield FG and the deflecting plate 35 are formed separately has been described as an example. However, the deflecting plate 35 may be formed integrally with the windshield FG. For example, as shown in FIG. 12, by integrally forming the deflecting portions 35A and 35B in the windshield FG, the deflecting plate 37 can be omitted.

  Further, in the control unit 45 of the distance measuring apparatus 30 of the second embodiment, a routine similar to the operation control routine R1 of the first embodiment may be executed. In that case, for example, the wiper WP may be operated after step S15 to positively remove foreign matter.

[Modification]
In the above embodiment, the case where the deflecting units 17A, 17B, 35A, and 35B can deflect the emitted lights EL1 and EL2 in a certain direction has been described. However, one or both of the deflecting units 17A and 17B and one or both of the deflecting units 35A and 35B may be a variable deflecting unit having a function of deflecting the emitted lights EL1 and EL2 in a variable direction. For example, the variable deflection unit may include a liquid crystal alignment control element.

  FIG. 13 is a top view of the automobile M equipped with the distance measuring device 10 in the first embodiment when the deflection unit 17B is a variable deflection unit. FIG. 13 shows a case where the polarization direction of the deflecting unit 17B changes from the state of FIG. 1, that is, from the irradiation light center line AX to the Y direction.

  For example, in the first embodiment, by making the deflecting unit 17B a variable deflecting unit, the outgoing light EL2 is deflected in the width direction of the automobile M, that is, in the Y direction according to the road conditions, and is applied to an area different from the irradiation light LL1. The light LL2 may be irradiated. For example, when operating as in the above-described operation control routine R1, the deflection direction of the irradiation light LL2 is changed in the normal scanning mode in which the irradiation lights LL1 and LL2 are in a redundant state that can be used for distance measurement without any problem. Alternatively, a plurality of areas may be measured.

  The determination as to whether or not to irradiate the irradiation light LL1 and the irradiation light LL2 to another area is made based on, for example, a situation in front of the vehicle M prepared in advance or obtained by the distance measurement devices 10 and 30. You may. The determination as to whether to irradiate the irradiation light LL1 and the irradiation light LL2 to another area may be made based on, for example, map data.

  In the above-described embodiment, the case has been described where the emitted lights EL1 and EL2 are deflected by the deflecting units 17A, 17B, 35A, and 35B having the function of the transmission type deflecting element. However, the emitted lights EL1 and EL2 may be deflected by the deflecting unit having the function of the reflection-type deflecting element and irradiated as the irradiation light LL1 and the irradiation light LL2.

  The various configurations and the like in the above-described embodiments are merely examples, and can be appropriately selected according to the application and the like.

Reference Signs List 10 distance measuring device 11, 31 housing 11C, 31C opening 13, 33 laser emission light receiving device 15 protection plate 17, 35 deflection plate 17A, 35A first deflection portion 17B, 35B second deflection portion 31E opening end WP wiper

Claims (9)

A light emitting unit that emits first emitted light in a first direction and emits second emitted light in a second direction;
A first deflecting unit that deflects the first outgoing light;
A first irradiation area irradiated with the first emission light deflected by the first deflection unit and a second irradiation area irradiated with the second emission light at least partially overlap each other A distance measuring device characterized by the following. A second deflecting unit for deflecting the second emitted light,
2. The distance measuring apparatus according to claim 1, wherein the second irradiation area is an area irradiated with the second emitted light that has passed through the second deflection unit. 3.   The distance measuring device according to claim 2, further comprising a holding member that holds the first deflecting unit or the second deflecting unit.   When an obstacle is present on one of the optical paths of the first irradiation light and the second irradiation light, the light emitting unit emits only light included in the other irradiation light. The distance measuring apparatus according to claim 1.   The distance measuring apparatus according to any one of claims 1 to 4, further comprising a removing unit configured to remove an obstacle on an optical path of the first irradiation light and the second irradiation light.   A light receiving unit configured to receive the first irradiation light and the second irradiation light reflected by the distance measurement target; and the light emitting unit outputs the reflected first irradiation light and the second irradiation light. The distance measuring apparatus according to any one of claims 1 to 5, wherein an emission mode of the first emission light and the second emission light is changed according to a result of light reception.   The light emitting unit includes a laser light source that emits the first emission light and the second emission light, and the light emission unit emits the first emission light in a manner to scan the first emission light in the first direction. The distance measuring apparatus according to any one of claims 1 to 6, wherein the light is emitted in such a manner as to scan the second emitted light in a second direction.   The distance measuring apparatus according to claim 1, wherein the first deflecting unit is capable of deflecting the first outgoing light in a variable direction. A light emitting unit that emits first emitted light in a first direction and emits second emitted light in a second direction;
A first deflecting unit that deflects the first outgoing light;
A control unit for controlling the light emitting unit, and a distance measuring method for a distance measuring device having:
The control unit causes the light emission unit to emit the first emission light,
The control unit causes the light emission unit to emit the second emission light,
A first irradiation area irradiated with the first emission light deflected by the first deflection unit and a second irradiation area irradiated with the second emission light at least partially overlap each other A distance measuring method characterized by the following.

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