WO2018173589A1

WO2018173589A1 - Distance measurement device and movement device

Info

Publication number: WO2018173589A1
Application number: PCT/JP2018/005889
Authority: WO
Inventors: 智浩江川; 佐伯　哲夫; 石丸　裕; 岡本　修治
Original assignee: 日本電産株式会社
Priority date: 2017-03-22
Filing date: 2018-02-20
Publication date: 2018-09-27

Abstract

A movement device that travels on a road comprises a distance measurement device. The distance measurement device radiates light to the exterior, receives reflection light reflected by an exterior object, and measures the distance to the object on the basis of the result of receiving the reflection light. The distance measurement device comprises a light source that emits light, a light radiation unit that radiates light to the exterior, and a motor having a shaft capable of rotating together with the light radiation unit about a central axis. The light radiation unit has a reflection member having a reflection surface that reflects light emitted by the light source, an adjustment member capable of adjusting the tilt of the reflection surface in a first circumferential direction about a first axis that lies in the reflection surface, and a support member for supporting the reflection member. The first axis is perpendicular to the axial direction, which is aligned with the central axis, and passes through a light reflection point on the reflection surface. The reflection member additionally has a first curved surface. The curvature of the first curved surface with respect to the first axis is fixed when viewed from a direction parallel to the first axis.

Description

Distance measuring device and moving device

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

In recent years, mobile devices such as automatic guided vehicles for carrying goods have been introduced in factories, warehouses, and the like. A distance measuring device is mounted on the moving device in order to avoid collision with surrounding objects. The distance measuring device detects the presence / absence of a surrounding object and the distance to the object based on the result of receiving the reflected light of the laser light applied to the surroundings. *

In addition, as an example of the prior art related to the present invention, Patent Document 1 teaches an automatic guided vehicle equipped with a laser obstacle detection sensor. In order to prevent the laser obstacle detection sensor from detecting the road surface as an obstacle, the laser light is irradiated with the optical axis of the laser light reflected by the light projection mirror facing upward from the horizontal line.

Japanese Patent Laid-Open No. 10-10233

However, when adjusting the tilt of the mirror that reflects the laser beam in order to change the reflection direction of the laser beam, if the reflection point of the laser beam on the reflecting surface is shifted, the base point of the laser beam irradiated to the outside changes. Therefore, an error may occur in the measurement result of the distance measuring device. Patent Document 1 makes no mention of this point. *

In view of the above situation, an object of the present invention is to provide a distance measuring device and a moving device that can reduce a measurement error due to adjustment of the inclination of a reflecting surface.

In order to achieve the above object, an exemplary distance measuring device of the present invention irradiates light outside, receives reflected light of the light reflected by the external object, and receives the reflected light as a result of receiving the reflected light. A distance measuring device for measuring a distance between the object and the light source, a light source that emits the light, a light irradiation unit that irradiates the light to the outside, and the light irradiation unit with a central axis as a center And a motor having a rotatable shaft, wherein the light irradiating portion has a reflecting member having a reflecting surface for reflecting the light emitted from the light source, and a first axis on the reflecting surface. An adjustment member capable of adjusting the inclination of the reflection surface in a first circumferential direction; and a support member that supports the reflection member, wherein the first axis is perpendicular to the axial direction along the central axis. The reflection member passes through a reflection point of the light on the reflection surface; Further has a first curved surface, when viewed from the first direction parallel to the axis, the curvature of the first curved surface with respect to the first axis is configured to be constant. *

In order to achieve the above object, an exemplary distance measuring device of the present invention irradiates light outside, receives reflected light of the light reflected by the external object, and receives the reflected light. A distance measuring device for measuring a distance between the object based on a result, a light source that emits the light, a light irradiation unit that irradiates the light to the outside, and the light irradiation around a central axis And a motor having a shaft that can rotate together with a part, wherein the light irradiation part includes a MEMS mirror element having a mirror part that reflects the light emitted from the light source by a reflection surface, and is on the reflection surface The tilt of the reflecting surface can be adjusted in the first circumferential direction by swinging the mirror portion in a first circumferential direction around the first axis, and the first axis is the central axis. Perpendicular to the axial direction along the reflective surface It is configured to pass through the reflection point. *

In order to achieve the above object, an exemplary mobile device of the present invention is a mobile device that travels on a road and includes the above-described distance measuring device.

According to the exemplary distance measuring device and the moving device of the present invention, it is possible to reduce measurement errors caused by adjusting the inclination of the reflecting surface.

FIG. 1 is a schematic side sectional view of a distance measuring device according to an embodiment of the present invention. FIG. 2 is a block diagram showing an electrical configuration of the distance measuring apparatus according to the embodiment of the present invention. FIG. 3 is a diagram illustrating a first configuration example of the light projecting mirror unit. FIG. 4 is a diagram illustrating a second configuration example of the light projecting mirror unit. FIG. 5 is a diagram illustrating a third configuration example of the light projecting mirror unit. FIG. 6 is a diagram illustrating a fourth configuration example of the light projecting mirror unit. FIG. 7 is a perspective view of a moving device according to an embodiment of the present invention. FIG. 8 is a side view of the moving apparatus according to the embodiment of the present invention. FIG. 9 is a plan view of the moving device according to the embodiment of the present invention as viewed from above.

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

<1. First Embodiment> <1-1. Definition in Distance Measuring Device> The distance measuring device 7 that functions as a laser range finder will be described. First, in the distance measuring device 7, a direction Da parallel to the central axis J of the motor 79 is referred to as “axial direction Da”. Furthermore, in the axial direction Da, the direction from the motor 79 toward the laser light source 71 is referred to as “upward”, and the direction from the laser light source 71 toward the motor 79 is referred to as “downward”. Further, on the surface of each component, the surface facing upward in the axial direction Da is called “upper surface”, and the surface facing downward in the axial direction Da is called “lower surface”. *

Further, a direction orthogonal to the central axis J is referred to as a “radial direction”, and a circumferential direction around the central axis J is referred to as a “circumferential direction”. Further, in the radial direction, a direction toward the central axis J is referred to as “inward”, and a direction away from the central axis J is referred to as “outward”. Further, of the side surfaces of each component, a side surface facing inward in the radial direction is called an “inner side surface”, and a side surface facing outward in the radial direction is called an “outer side surface”. *

Note that the direction and surface designations described above do not indicate the positional relationship and direction when incorporated in an actual device. In the following, the phrase “constant” includes “substantially constant”. *

<1-2. Configuration of Distance Measuring Device> The distance measuring device 7 is a device that measures a distance from an external object. The distance measuring device 7 irradiates the projection light L1 to the outside, receives the reflected light L2 of the projection light L1 reflected by the external object, and determines the distance to the object based on the light reception result of the reflected light L2. taking measurement. FIG. 1 is a cross-sectional view illustrating a configuration example of the distance measuring device 7. In FIG. 1, the distance measuring device 7 is cut along a cut surface including the central axis J of the motor 79. The distance measuring device 7 includes a laser light source 71, a collimating lens 72, a light projecting mirror unit 73, a light receiving lens 74, a light receiving mirror unit 75, a light receiving unit 77, a rotating housing 78, a motor 79, a housing, and a housing. A body 80, a substrate 81, a wiring 82, and a gyro sensor 83 are included. *

The casing 80 has, for example, a substantially cylindrical shape extending in the vertical direction in appearance and stores the laser light source 71 and the light projecting mirror unit 73 in the internal space. More specifically, the housing 80 stores the components 71 to 79 and 81 to 83 of the distance measuring device 7 as described above. A laser light source 71 and a substrate 81 on which a gyro sensor 83 is mounted are provided on the lower surface of the upper end portion in the axial direction Da of the housing 80. Note that the shape of the housing 80 in the external view is not limited to the example of the present embodiment, and may be, for example, a prismatic shape. *

The laser light source 71 emits laser light in the infrared region, for example, below the axial direction Da. The type of the laser light source 71 is not particularly limited, but a laser element that emits laser light in the infrared region is preferable in order to reduce manufacturing costs. *

The collimating lens 72 is disposed below the laser light source 71 in the axial direction Da. The collimating lens 72 emits laser light emitted from the laser light source 71 as parallel light below the axial direction Da. *

The light projecting mirror 73 is disposed below the collimating lens 72 in the axial direction Da, and is fixed to the rotary casing 78. The light projection mirror unit 73 is an example of a light irradiation unit that irradiates laser light to the outside of the distance measuring device 7. The optical path of the laser light emitted from the laser light source 71 and reaching the light projection mirror unit 73 is on the central axis J. The light projection mirror unit 73 reflects the laser beam emitted from the collimator lens 72 at the reflection point Pr on the reflection surface 731a, and emits the reflected laser beam as the projection light L1. A specific configuration of the light projecting mirror unit 73 will be described later. *

The rotary casing 78 is fixed to the shaft 79A of the motor 79, and is driven to rotate about the central axis J by the motor 79. Along with the rotation of the rotary casing 78, the light projecting mirror 73 is also driven to rotate about the central axis J. Therefore, the projection light L1 is emitted in a range of 360 [degree] in the circumferential direction around the central axis J. *

The housing 80 has a light-transmitting light transmitting portion 801 in the middle of the vertical direction. The light transmission portion 801 is formed using, for example, a resin material, glass, or the like. The light transmission part 801 has a cylindrical part 801A and a curved part 801B through which the projection light L1 irradiated to the outside from the light projection mirror part 73 passes. The curved portion 801B is provided adjacent to the upper portion of the cylindrical portion 801A in the axial direction Da, and is curved so as to protrude outward in the radial direction. More specifically, the cylindrical portion 801A and the curved portion 801B have an arc shape centered on the central axis J when viewed from the axial direction Da. Alternatively, the cylindrical portion 801A and the curved portion 801B may be annular with the central axis J as the center when viewed from the axial direction Da. Further, the curved portion 801B may have a cylindrical shape or a truncated cone shape along the central axis J, but preferably the reflection point Pr is seen from the circumferential direction centering on the central axis J as shown in FIG. The center is an arc shape. Furthermore, the inner side surface of the curved portion 801B facing the reflecting surface 731a is a concave surface. Therefore, the irradiation direction DL of the projection light L1 irradiated to the outside through the light transmission unit 801 is centered on the irradiation direction DL of the projection light L1 by adjusting the inclination of the reflection surface 731a described later and rotating the projection mirror unit 73. It is possible to suppress variation due to the movement in the circumferential direction around the axis J. *

Further, in the curved portion 801B, more preferably, the shortest distance r1 from the reflection point Pr of the projection light L1 on the reflective surface 731a to the inner surface of the curved portion 801B is constant as shown in FIG. That is, the curvature r2 of the first curved surface 731b with respect to the reflection point Pr is constant when viewed from the circumferential direction centered on the central axis J. In this way, it is possible to prevent a change in the distance r1 until the projection light L1 reaches the curved portion 801B of the light transmission portion 801 from the reflection point Pr on the reflection surface 731a. Therefore, variation in the irradiation direction DL of the projection light L1 irradiated to the outside can be prevented. *

The projection light L1 passes through the curved portion 801B and is irradiated to the outside of the housing 80. The curved portion 801B is arranged over a predetermined angular range θ in the circumferential direction around the central axis J so as to correspond at least to the predetermined angular range θ of scanning with the projection light L1. In the present embodiment, the predetermined angle range θ is set to 270 [degree] around the central axis J as an example. That is, the projection light L1 is transmitted through the curved portion 801B at least in the range of 270 degrees around the central axis J. Outside the angle range θ, the projection light L1 is blocked by the inner wall of the housing 80, the wiring 82, or the like. *

The light receiving lens 74 is provided on the side surface in the radial direction of the rotating housing 78. The light receiving mirror portion 75 is fixed to the lower surface of the upper end portion in the axial direction Da of the rotary casing 78 and is located below the light projecting mirror portion 73 in the axial direction Da. The light receiving portion 77 is positioned below the light receiving mirror portion 75 and is fixed to the upper surface of the lower end portion in the axial direction Da of the rotating housing 78. The light receiving lens 74 and the light receiving unit 77 are rotatable together with the rotating housing 78. The light receiving unit 77 is not limited to this example, and may be configured not to rotate. That is, for example, the light receiving unit 77 may be configured not to be fixed to the rotating casing 78 and to rotate around the central axis J. *

The projection light L1 emitted from the distance measuring device 7 is reflected by an external object and becomes diffused light. Part of the diffused light passes through the cylindrical portion 801A as reflected light L2 and enters the light receiving lens 74. The reflected light L2 transmitted through the light receiving lens 74 is incident on the light receiving mirror unit 75 and reflected downward by the light receiving mirror unit 75. The reflected reflected light L2 is received by the light receiving unit 77. The optical path of the reflected light L 2 that is reflected by the light receiving mirror unit 75 and reaches the light receiving unit 77 is on the central axis J. The light receiving unit 77 converts the received light into an electrical signal by photoelectric conversion.

The cylindrical portion 801A is configured in a circumferential range similar to the range in which the curved portion 801B is configured. When the rotating housing 78 is driven to rotate by the motor 79, the light receiving lens 74, the light receiving mirror unit 75, and the light receiving unit 77 are rotated together with the light projecting mirror unit 73. *

The motor 79 has a shaft 79 A that can rotate together with the projection mirror 73 around the central axis J. The motor 79 is connected to the substrate 81 by the wiring 82 and is driven to rotate when energized from the substrate 81. The motor 79 rotates the rotary casing 78 at a predetermined rotation speed. For example, the rotary casing 78 is driven to rotate at about 3000 rpm. The wiring 82 is routed in the vertical direction of the axial direction Da along the rear inner wall of the housing 80. *

The gyro sensor 83 detects the angular velocity or each acceleration of the distance measuring device 7. *

In addition, the distance measuring device 7 may further include a wavelength filter 76 that extracts light in the infrared region. The wavelength filter 76 is provided between the light receiving mirror unit 75 and the light receiving unit 77, for example. The wavelength filter 76 may be fixed to the rotary casing 78 and rotatable with the rotary casing 78. Alternatively, the wavelength filter 76 may be configured not to rotate. That is, the wavelength filter 76 may be configured not to be fixed to the rotary casing 78 and to rotate around the central axis J, for example. The reflected light L 2 reflected by the light receiving mirror unit 75 passes through the wavelength filter 76 and is received by the light receiving unit 77. By providing the wavelength filter 76, it is possible to suppress or prevent light derived from, for example, sunlight other than the reflected light L2 from entering the light receiving mirror unit 75. Therefore, noise included in the light reception result of the light receiving unit 77 can be reduced, so that the measurement accuracy of the distance measuring device 7 can be improved. *

<1-3. Electrical Configuration of Distance Measuring Device> Next, the electrical configuration of the distance measuring device 7 will be described. FIG. 2 is a block diagram showing an electrical configuration of the distance measuring device 7 according to one embodiment of the present invention. As shown in FIG. 2, the distance measuring device 7 includes a laser light emitting unit 701, a laser light receiving unit 702, a distance meter side unit 703, an arithmetic processing unit 704, a data communication interface 705, and a driving unit 707. Also have. *

The laser light emitting unit 701 includes a laser light source 71 (see FIG. 1), an LD driver 701a, and the like. The LD driver 701 a is mounted on the substrate 81 and controls driving of the laser light source 71. The laser light receiving unit 702 includes a light receiving unit 77, a comparator 702a, and the like. The comparator 702 a is mounted on the substrate 81 and receives an electrical signal output from the light receiving unit 77. Further, the comparator 702a compares the level of the electric signal with a predetermined threshold level, and outputs a measurement pulse having a high level or a low level according to the comparison result to the distance measuring unit 703. *

The laser emission unit 701 emits laser light using the laser emission pulse output from the arithmetic processing unit 704 as a trigger. At this time, the projection light L 1 is emitted from the light projecting mirror unit 73. When the emitted projection light L1 is reflected by an external object OJ (hereinafter, measurement object OJ), the reflected light L2 is received by the laser light receiving unit 702. A measurement pulse is generated according to the amount of light received by the laser light receiving unit 702, and the measurement pulse is output to the distance measuring unit 703. *

Here, a reference pulse is output from the arithmetic processing unit 704 to the distance measuring unit 703. The distance measuring unit 703 can acquire the distance to the external measurement object OJ by measuring the elapsed time from the rising timing of the reference pulse to the rising timing of the measurement pulse. That is, the distance measuring unit 703 measures the distance by a so-called TOF (Time Of Flight) method. The distance measurement result is output from the distance measurement unit 703 as measurement data. *

The drive unit 707 controls the rotational drive of the motor 79. The motor 79 is driven to rotate at a predetermined rotation speed by the drive unit 707. The arithmetic processing unit 704 outputs a laser emission pulse every time the motor 79 rotates by a predetermined unit angle. For example, the predetermined unit angle is 1 [degree]. As a result, the laser light emitting unit 701 emits light and the projection light L1 is emitted from the light projecting mirror unit 73 each time the rotating housing 78 and the light projecting mirror unit 73 rotate by a predetermined unit angle. *

The arithmetic processing unit 704 is arranged on an orthogonal coordinate system based on the distance measuring device 7 based on the rotation angle position of the motor 79 at the timing when the laser emission pulse is output and the measurement data obtained corresponding to the laser emission pulse. The position information of is generated. That is, the position of the external measurement object OJ is acquired based on the rotation angle position of the projection mirror unit 73 and the measured distance. The acquired position information is output from the arithmetic processing unit 704 as measurement distance data. In this way, a distance image of the external measurement object OJ can be acquired by scanning with the projection light L1 in the angle range θ. *

The data communication interface 705 is a communication unit for outputting the measurement distance data output from the arithmetic processing unit 704 to an external device. *

In addition, the distance measurement device 7 determines whether or not the external measurement object OJ is located in a predetermined area set around the distance measurement device 7 based on the measurement distance data output from the arithmetic processing unit 704. You may further provide the object determination part (not shown) to determine. For example, if the position of a certain external measurement object OJ indicated by the measurement distance data is located within a predetermined area, the object determination unit determines that the external measurement object OJ is located within the predetermined area. When the object determination unit determines that the external measurement object OJ is located within the predetermined area, the object determination unit outputs a detection signal that is a flag as a high level. On the other hand, when the external measurement object OJ is not located within the predetermined area, a detection signal having a low level is output. In this way, the distance measuring device 7 can be used as a device for detecting an obstacle (that is, an external measuring object OJ) located in a predetermined area around the distance measuring device 7. *

<1-4. Configuration of Projection Mirror Unit> Next, a specific configuration of the projection mirror unit 73 will be described with reference to first to fourth configuration examples. *

<1-4-1. First Configuration Example> First, a first configuration example of the light projecting mirror unit 73 will be described. FIG. 3 is a perspective view illustrating a first configuration example of the light projecting mirror unit 73. As shown in FIG. 3, the light projecting mirror unit 73 includes a reflection member 731, an adjustment member 732, a support member 733, and a fixing member 734. *

The reflective member 731 has a reflective surface 731a and a first curved surface 731b. The reflection surface 731 a reflects the laser light emitted from the laser light source 71. In FIG. 3, the curvature r2 of the first curved surface 731b with respect to the first axis Ax1 is constant as viewed from the direction parallel to the first axis Ax1. That is, the shortest distance r2 from the first axis Ax1 to the first curved surface 731b is constant when viewed from a direction parallel to the first axis Ax1. The first axis Ax1 is perpendicular to the axial direction Da along the central axis J and passes through the reflection point Pr of the laser beam on the reflection surface 731a. *

The material of the reflecting member 731 is not particularly limited, and a metal material, a resin material, glass, or the like can be used. More specifically, the reflecting surface 731a is provided on a member formed using the above-described material. *

The adjusting member 732 can adjust the inclination of the reflecting surface 731a in the first circumferential direction Dc1 centering on the first axis Ax1 on the reflecting surface 731a. The first circumferential direction Dc1 is a circumferential direction around the first axis Ax1. More specifically, the first circumferential direction Dc1 is a circumferential direction when the first axis Ax1 is a rotation axis, and is, for example, the pitching direction of the reflecting surface 731a. In the first configuration example, the adjustment member 732 is provided on the upper and lower portions of the reflection member 731. As shown in FIG. 3, the adjustment member 732 is reflected in the first circumferential direction Dc1 by rotating the reflecting member 731 in the first circumferential direction Dc1 with respect to the support member 733 around the first axis Ax1. The inclination of the surface 731a can be adjusted. *

The support member 733 supports the reflection member 731. The support member 733 includes a storage portion 733 a that stores the reflection member 731. The storage portion 733a has a second curved surface 733b. The second curved surface 733 b faces the first curved surface 731 b and is along the first curved surface 731 b of the reflecting member 731. *

According to the light projection mirror unit 73 of the first configuration example, the adjustment member 732 tilts the reflection surface 731a of the reflection member 731 in the first circumferential direction Dc1 with the first axis Ax1 on the reflection surface 731a as the center. By adjusting, the irradiation direction DL of the projection light L1 reflected by the reflecting surface 731a and irradiated to the outside can be adjusted to the first circumferential direction Dc1. The reflection member 731 supported by the support member 733 has a first curved surface 731b having a constant curvature r2 with respect to the first axis Ax1 on the reflection surface 731a when viewed from a direction parallel to the first axis Ax1. Have. Therefore, the inclination of the reflection surface 731a can be easily adjusted in the first circumferential direction Dc1 without shifting the reflection point Pr of the projection light L1 on the reflection surface 731a. Therefore, the measurement error of the distance measuring device 7 due to the adjustment of the inclination of the reflecting surface 731a can be reduced. *

Further, when the distance measuring device 7 is arranged with the central axis J parallel to the vertical line, even if the distance measuring device 7 is at a height close to the ground (such as a road surface of a road), the first circumferential direction Dc1 described above. For example, the reflection of the projection light L1 on the ground can be suppressed. Therefore, measurement errors such as the distance to an external object (measurement object OJ) can be reduced. *

Further, the reflection member 731 supported by the support member 733 is stored in the storage portion 733a having the second curved surface 733b along the first curved surface 731b. Therefore, when the inclination of the reflecting surface 731a is adjusted, the first curved surface 731b of the reflecting member 731 can be moved along the second curved surface 733b. Therefore, the tilt of the reflection surface 731a can be easily adjusted in the first circumferential direction Dc1 without shifting the reflection point Pr of the laser beam on the reflection surface 731a. Therefore, the measurement error of the distance measuring device 7 due to the adjustment of the inclination of the reflecting surface 731a can be reduced. *

The fixing member 734 fixes the reflecting member 731 to the support member 733. More specifically, after the inclination of the reflection surface 731 a is adjusted by the adjustment member 732, the reflection member 731 is fixed to the support member 733 by the fixing member 734. By doing so, it is possible to prevent a deviation in the inclination of the reflecting surface 731a, and thus it is possible to prevent a deviation in the irradiation direction DL of the projection light L1 after adjustment of the reflecting surface 731a. The fixing member 734 is not particularly limited, and an acrylic adhesive, an ultraviolet curing agent, or the like can be used. *

<1-4-2. Second Configuration Example> Next, a second configuration example of the light projecting mirror unit 73 will be described. In the second configuration example, a configuration different from the first configuration example will be described, and the same components as those in the first configuration example may be denoted by the same reference numerals, and the description thereof may be omitted. *

FIG. 4 is a perspective view illustrating a second configuration example of the light projecting mirror unit 73. In the light projection mirror unit 73 of the second configuration example, as illustrated in FIG. 4, the adjustment member 732 is further arranged in a plurality of second circumferential directions Dc2 around the respective second axes Ax2 on the reflection surface 731a. The inclination of the reflecting surface 731a can be adjusted. Each second axis Ax2 intersects the first axis Ax1 and passes through the reflection point Pr on the reflection surface 731a. Further, the second circumferential direction Dc2 is more specifically a circumferential direction when the second axis Ax2 is used as a rotation axis. The first curved surface 731b of the reflecting member 731 is a spherical surface having a constant curvature r2 with respect to the reflection point Pr. That is, as shown in FIG. 4, the shortest distance r2 from the reflection point Pr on the reflection surface 731a to the first curved surface 731b is constant. *

According to the light projecting mirror portion 73 of the second configuration example, the adjustment member 732 further tilts the reflection surface 731a of the reflection member 731 in the second circumferential direction Dc2 around the second axis Ax2 on the reflection surface 731a. By adjusting the irradiation direction DL, the irradiation direction DL of the projection light L1 reflected by the reflecting surface 731a and irradiated to the outside can be adjusted to the second circumferential direction Dc2. The first curved surface 731b of the reflecting member 731 has a curvature r2 with respect to the reflection point Pr on the reflecting surface 731a.
Is a constant spherical surface. Therefore, the tilt of the reflection surface 731a can be easily adjusted to the first circumferential direction Dc1 and the second circumferential direction Dc2 without shifting the reflection point Pr of the laser beam on the reflection surface 731a. Therefore, the measurement error of the distance measuring device 7 due to the adjustment of the inclination of the reflecting surface 731a can be further reduced.

Further, the second circumferential direction Dc2 is plural in FIG. 4, but is not limited to this example. There may be one second circumferential direction Dc2. More specifically, the second circumferential direction Dc2 only needs to include the third circumferential direction Dc3 centered on the third axis Ax3 on the reflecting surface 731a. The third axis Ax3 is orthogonal to the first axis Ax1 and passes through the reflection point Pr on the reflection surface 731a. The third circumferential direction Dc3 is more specifically a circumferential direction when the third axis Ax3 is a rotation axis, and is, for example, the yawing direction of the reflecting surface 731a. In this way, the inclination of the reflecting surface 731a can be adjusted also in the third circumferential direction Dc3. *

<1-4-3. Third Configuration Example> Next, a third configuration example of the light projecting mirror unit 73 will be described. In the third configuration example, a configuration different from the first and second configuration examples will be described, and the same components as those in the first and second configuration examples may be denoted by the same reference numerals, and the description thereof may be omitted. . *

FIG. 5 is a perspective view illustrating a third configuration example of the light projecting mirror unit 73. The light projecting mirror unit 73 of the third configuration example includes a MEMS mirror element 735. The MEMS mirror element 735 includes a mirror portion 735a that reflects the laser light emitted from the laser light source 71 on the reflection surface 731a. The MEMS mirror element 735 swings the mirror portion 735a in the first circumferential direction Dc1 centered on the first axis Ax1 on the reflection surface 731a, thereby tilting the reflection surface 731a in the first circumferential direction Dc1. It can be adjusted. The first axis Ax1 is perpendicular to the axial direction Da along the central axis J and passes through the reflection point Pr of the laser beam on the reflection surface 731a. *

The MEMS mirror element 735 adjusts the inclination of the reflecting surface 731 a based on the detection result of the gyro sensor 83 that detects the angular velocity or the angular acceleration of the distance measuring device 7. More specifically, a mirror drive control unit (not shown) is mounted on the substrate 81, for example, and controls the swing drive of the mirror unit 735a based on the detection result of the gyro sensor 83. *

According to the light projecting mirror unit 73 of the third configuration example, the light projecting mirror unit 73 includes the mirror unit 735a of the MEMS mirror element 735 in the first circumferential direction Dc1 centered on the first axis Ax1 on the reflection surface 731a. And the tilting direction of the reflecting surface 731a is adjusted to the first circumferential direction Dc1, so that the irradiation direction Dx of the projection light L1 reflected by the reflecting surface 731a and irradiated to the outside is changed to the first circumferential direction. It can be adjusted to Dc1. Further, the mirror portion 735a of the MEMS mirror element 735 is very small compared to the optical path length of the projection light L1 irradiated to the outside. For this reason, even if the mirror portion 735a is driven to swing, it can be said that the reflection point Pr of the laser beam on the reflection surface 731a does not shift. Therefore, the tilt of the reflecting surface 731a can be easily adjusted in the first circumferential direction Dc1 at any timing without shifting the reflection point Pr of the laser light on the reflecting surface 731a. Therefore, the measurement error of the distance measuring device 7 due to the adjustment of the inclination of the reflecting surface 731a can be reduced. *

Further, according to the light projecting mirror unit 73 of the third configuration example, the mirror unit 735a is driven to swing based on the detection result of the angular velocity or angular acceleration of the distance measuring device 7 by the sensor 83. Therefore, for example, the inclination of the reflecting surface 731a can be adjusted in consideration of the inclination of the distance measuring device 7 with respect to the vertical line. Therefore, for example, when the distance measuring device 7 is inclined in the first circumferential direction Dc1, the inclination of the reflecting surface 731a is set in the first circumferential direction Dc1 in consideration of the inclination of the first circumferential direction Dc1 in the distance measuring device 7. Can be adjusted. Therefore, even if the distance measuring device 7 is at a height close to the ground (road surface of the road, etc.), reflection of the projection light L1 on the ground (road surface of the road, etc.) can be more reliably suppressed. *

<1-4-4. Fourth Configuration Example> Next, a fourth configuration example of the light projecting mirror unit 73 will be described. In the fourth configuration example, a configuration different from the first to third configuration examples will be described, and the same components as those in the first to third configuration examples will be denoted by the same reference numerals and description thereof may be omitted. . *

FIG. 6 is a perspective view illustrating a fourth configuration example of the light projecting mirror unit 73. As shown in FIG. 6, the light projecting mirror unit 73 of the fourth configuration example includes a MEMS mirror element 736. The MEMS mirror element 736 can swing the mirror portion 735a in a first circumferential direction Dc1 centered on the first axis Ax1 and in a third circumferential direction Dc3 centered on the third axis Ax3. The third axis Ax3 is orthogonal to the first axis Ax1 and passes through the reflection point Pr on the reflection surface 731a. *

More specifically, the MEMS mirror element 736 swings the mirror portion 735a in the first circumferential direction Dc1 centering on the first axis Ax1 on the reflection surface 731a, thereby changing the inclination of the reflection surface 731a to the first. 1 in the circumferential direction Dc1. Further, the MEMS mirror element 736 further swings the mirror portion 735a in the third circumferential direction Dc3 centering on the third axis Ax3 on the reflecting surface 731a, thereby reducing the inclination of the reflecting surface 731a to the third circumference. Adjustment is possible in the direction Dc3. In this way, for example, the inclination of the reflecting surface 731a of the mirror portion 735a can be adjusted also in the third circumferential direction Dc3 that is the yawing direction of the reflecting surface 731a. *

<2. Second Embodiment> Next, a second embodiment will be described. In the second embodiment, the distance measuring device 7 is mounted on the moving device 200 that travels on the road G. The mobile device 200 can travel autonomously by two-wheel drive. In the second embodiment, a configuration different from that of the first embodiment will be described, and the same components as those in the first embodiment may be denoted by the same reference numerals, and the description thereof may be omitted. *

The use of the moving device 200 on which the distance measuring device 7 is mounted is not limited to the example of the present embodiment, but is suitable for an automatic guided vehicle for use in, for example, carrying goods. For example, automated guided vehicles are designed to be short to facilitate loading and unloading of articles. Therefore, the distance measuring device 7 is arranged at a position relatively close to the road surface of the road G when mounted on the automatic guided vehicle. Therefore, the laser beam is emitted from a position relatively close to the road surface. Here, as the irradiation distance of the laser light becomes longer, the spot size of the laser light becomes larger. Therefore, the laser light is easily reflected on the road surface of the road G. The reflected light from the road surface may cause detection errors of the measurement object OJ around the automatic guided vehicle, increase the measurement error of the distance to the measurement object OJ, or cause a measurement abnormality. Sometimes On the other hand, the moving device 200 as the automatic guided vehicle does not shift the reflection point Pr on the reflection surface 731a of the distance measuring device 7, and the inclination of the reflection surface 731a is at least in the first circumferential direction Dc1 (for example, the pitching direction). Can be adjusted. Therefore, the moving device 200 as an automatic guided vehicle can make it difficult for the laser light to be reflected on the road surface of the road G even when the irradiation distance of the laser light becomes long. Therefore, even in a short moving device 200 such as an automatic guided vehicle, generation of detection errors due to reflected light from the road surface, increase in measurement errors, and generation of measurement abnormalities can be more effectively suppressed or prevented. can do. *

<2-1. Definition in Moving Device> In the second embodiment, the upper part of the vertical line on the road G is referred to as “upper”, and the lower part of the vertical line is referred to as “lower”. Further, on the surface of each component, the surface facing upward of the vertical ship is called “upper surface”, and the surface facing downward of the vertical line is called “lower surface”. *

A direction perpendicular to the vertical line is referred to as a “horizontal direction”. Among the horizontal directions, the normal traveling direction of the moving device 200 is referred to as “front”, and the direction opposite to the normal traveling direction is referred to as “rear”. Furthermore, of the horizontal directions, the direction orthogonal to the normal traveling direction and facing the right side toward the front is referred to as “right”, and is orthogonal to the normal traveling direction and toward the left side toward the front. The direction is called “left”. Further, in each component of the moving device 200, a surface facing in the horizontal direction is referred to as a “side surface”. *

The direction and surface designations described above do not indicate the positional relationship and direction in an actual apparatus. *

<2-2. Configuration of Moving Device> FIG. 7 is a perspective view of a moving device 200 according to an embodiment of the present invention. FIG. 8 is a side view of the moving apparatus 200 according to an embodiment of the present invention. FIG. 9 is a plan view of the moving device 200 according to an embodiment of the present invention as viewed from above. *

The moving device 200 includes a vehicle body 1, a loading platform 2,

support portions

3L and 3R, drive

motors

4L and 4R,

drive wheels

5L and 5R, driven

wheels

6F and 6R, and a distance measuring device 7. Yes. *

The vehicle body 1 includes a base portion 1A and a base portion 1B. The plate-like pedestal 1B is fixed to the rear upper surface of the base 1A. The base part 1B has a triangular part Tr protruding forward. *

The plate-shaped loading platform 2 is fixed to the upper surface of the platform 1B. A load can be placed on the upper surface of the loading platform 2. The loading platform 2 extends further forward than the platform 1B. Thus, a gap S is formed between the front of the base 1A and the front of the loading platform 2. *

The support portion 3L is fixed to the left side of the base portion 1A and supports the drive motor 4L. The drive motor 4L is configured by an AC servo motor as an example. The drive motor 4L incorporates a reduction gear (not shown). The drive wheel 5L is attached to a shaft (not shown) of the drive motor 4L and contacts the road G. The drive wheel 5L can be rotated together with the shaft by the rotational drive of the drive motor 4L. *

The support portion 3R is fixed to the right side of the base portion 1A and supports the drive motor 4R. The drive motor 4R is configured by an AC servo motor as an example. The drive motor 4R incorporates a reduction gear (not shown). The drive wheel 5R is attached to a shaft (not shown) of the drive motor 4R and is in contact with the road G. The drive wheel 5R can be rotated together with the shaft by the rotational drive of the drive motor 4R. *

By rotating the

drive wheels

5L and 5R with the

drive motors

4L and 4R, the moving device 200 can be moved forward and backward on the road G. Further, by controlling so as to provide a difference in the rotational speeds of the

drive wheels

5L and 5R, the moving device 200 can be rotated clockwise or counterclockwise to change the direction. *

The driven wheel 6F is rotatably attached to the front side of the base portion 1A and is in contact with the road G. The driven wheel 6R is rotatably attached to the rear side of the base portion 1A and contacts the road G. The driven

wheels

6F and 6R rotate passively according to the rotation of the

drive wheels

5L and 5R. *

The distance measuring device 7 is a device that measures a distance from an external object (measurement object OJ). The distance measuring device 7 irradiates the projection light L1 to the outside, receives the reflected light L2 of the projection light L1 reflected by the external measurement object OJ, and measures the measurement object OJ based on the light reception result of the reflected light L2. Measure the distance between. Since the configuration of the distance measuring device 7 is the same as that of the first embodiment, the description thereof is omitted. *

The distance measuring device 7 is disposed at the front position of the apex of the triangular portion Tr of the base portion 1B in the gap S between the base portion 1A and the loading platform 2. The center axis J of the distance measuring device 7 is parallel to the vertical ship. In the gap S, at least the light transmission part 801 of the distance measuring device 7 is exposed. Without being blocked by the base 1 A and the loading platform 2 of the vehicle body 1 through the gap S, it is possible to irradiate the projection light L 1 from the distance measuring device 7 or to allow the reflected light L 2 to enter the distance measuring device 7 from the outside. It has become. *

Specifically, the projection light L1 irradiated from the distance measuring device 7 passes through the gap S, is irradiated to the outside of the moving device 200, and is scanned over the measurement range Rs having a predetermined angle range θ in the horizontal direction. The In this embodiment, as shown in FIG. 9, scanning is performed in the range of θ = 270 [degree] in the circumferential direction around the central axis J of the distance measuring device 7. More specifically, the angle range θ includes 180 [degree] in front of the moving device 200 and 45 [degree] in each of the left and right sides. The projection light L1 emitted from the distance measuring device 7 is reflected by the measurement object OJ and becomes diffused light. A part of the diffused light enters the distance measuring device 7 through the gap S as reflected light L2. The distance measuring device 7 measures the distance by a so-called TOF (Time Of Flight) method. Specifically, the distance measuring device 7 receives the reflected light L2 in which the projection light L1 is reflected by the measurement object OJ from the emission of the laser light that is reflected by the light projection mirror unit 73 and becomes the projection light L1. The distance to the measurement object OJ is measured based on the elapsed time until the light is received. Furthermore, the distance measuring device 7 acquires the position of the measurement object OJ based on the elapsed time and the scanning angle position of the projection light L1.

The moving device 200 is equipped with a distance measuring device 7 that can adjust the inclination of the reflecting surface 731a of the light projection mirror unit 73 at least in the first circumferential direction (for example, the pitching direction). For this reason, for example, since the light reflected by the light receiving unit 77 of the light reflected from the ground (road surface of the road, etc.) can be suppressed by adjusting the inclination, the measurement object OJ generated due to the reception of the light reflected from the ground can be suppressed. The measurement error of the distance between them can be reduced. In addition, since the distance measuring device 7 can reduce the measurement error due to the adjustment of the inclination of the reflecting surface 731a of the projection mirror unit 73, the measurement error such as the distance to the measurement object OJ can be reduced. Therefore, the mobile device 200 can accurately perform surrounding map information creation, self-position identification, obstacle detection, and the like. *

In addition, the mobile device 200 further includes a control unit U, a battery B, and a communication unit T as shown in FIGS. The control unit U, the battery B, and the communication unit T are accommodated in the base 1A. *

The control unit U is connected to the

drive motors

4L, 4R, the communication unit T, and the like. The control unit U is further connected to the distance measuring device 7 and receives various signals from the distance measuring device 7 to perform various controls. The control unit U also performs drive control of the

drive motors

4L and 4R. *

The communication unit T performs communication with an external tablet terminal (not shown) based on, for example, Bluetooth (registered trademark). Thereby, the mobile device 200 can be remotely operated by an external information device such as a tablet terminal. *

The battery B is composed of, for example, a lithium ion battery, and supplies power to each unit such as the distance measuring device 7, the control unit U, the communication unit T, and the like. *

<3. Others> The embodiment of the present invention has been described above. The scope of the present invention is not limited to the above-described embodiment. The present invention can be implemented with various modifications without departing from the spirit of the invention. In addition, the items described in the above embodiments can be arbitrarily combined as long as no contradiction occurs.

The present invention is useful for a distance measuring device mounted on a moving device such as an automatic guided vehicle, for example. *

DESCRIPTION OF SYMBOLS 1 ... Car body, 1A ... Base part, 1B ... Base part, 2 ... Cargo bed, 3L, 3R ... Support part, 4L, 4R ... Drive motor, 5L, 5R ...

Drive

6F, 6R ... driven wheel, 7 ... distance measuring device, 71 ... laser light source, 72 ... collimating lens, 73 ... projecting mirror unit, 701 ... laser emitting unit, 701a: LD driver, 702 ... laser light receiving unit, 702a ... comparator, 703 ... distance measuring unit, 704 ... arithmetic processing unit, 705 ... data communication interface, 707 ... drive Part, 731 ... reflective member, 731a ... reflective surface, 731b ... first curved surface, 732 ... adjustment member, 733 ... support member, 733 ... storage part, 733b ... first. Two curved surfaces 734 ... fixing members, 735, 736 ... EMS mirror element, 735a ... mirror part, 74 ... light receiving lens, 75 ... light receiving mirror part, 76 ... wavelength filter, 77 ... light receiving part, 78 ... rotating housing, 79 ..Motor, 80 ... housing, 801 ... transmission portion, 801A ... cylindrical portion, 801B ... curved surface portion, 81 ... substrate, 82 ... wiring, 83 ... gyro sensor , 200 ... moving device, U ... control unit, B ... battery, T ... communication unit, Tr ... triangular part, S ... gap, θ ... angle range, Rs · ..Measurement range, J ... center axis, L1 ... projection light, L2 ... reflection light, DL ... irradiation direction, Da ... axial direction, Pr ... reflection point, Ax1 ... -1st axis, Ax2 ... 2nd axis, Ax3 ... 3rd axis, Dc1 ... 1st circumferential direction, Dc2 ... 2nd , Dc3 ... third circumferential direction, r1, r2 ... curvature, OJ ... measurement object

Claims

A distance measuring device that irradiates light externally, receives reflected light of the light reflected by the external object, and measures a distance between the object based on a light reception result of the reflected light, A light source that emits the light, a light irradiation unit that irradiates the light to the outside, and a motor that has a shaft that can rotate with the light irradiation unit around a central axis, and the light irradiation unit includes: A reflecting member having a reflecting surface for reflecting the light emitted from the light source; and an adjusting member capable of adjusting the inclination of the reflecting surface in a first circumferential direction centered on a first axis on the reflecting surface; A supporting member that supports the reflecting member, wherein the first axis is perpendicular to an axial direction along the central axis, passes through the reflection point of the light on the reflecting surface, and the reflecting member is , Further having a first curved surface, When viewed from the direction parallel to the axis, the distance measuring device of curvature of the first curved surface with respect to said first axis is constant.
The distance measurement according to claim 1, wherein the support member has a storage portion that stores the reflection member, and the storage portion has a second curved surface that faces the first curved surface and extends along the first curved surface. apparatus.
The adjusting member is further capable of adjusting the inclination of the reflecting surface in a second circumferential direction centered on a second axis on the reflecting surface, and the second axis intersects the first axis. The distance measuring device according to claim 1, wherein the first curved surface is a spherical surface having a constant curvature with respect to the reflection point through the reflection point.
The second circumferential direction includes a third circumferential direction centered on a third axis on the reflection surface, and the third axis is orthogonal to the first axis and passes through the reflection point. 3. The distance measuring device according to 3.
The distance measuring device according to any one of claims 1 to 4, wherein the light irradiation unit further includes a fixing member that fixes the reflecting member to the support member.
A distance measuring device that irradiates light externally, receives reflected light of the light reflected by the external object, and measures a distance between the object based on a light reception result of the reflected light, A light source that emits the light, a light irradiation unit that irradiates the light to the outside, and a motor that has a shaft that can rotate with the light irradiation unit around a central axis, and the light irradiation unit includes: Including a MEMS mirror element having a mirror part for reflecting the light emitted from the light source by a reflecting surface, and swinging the mirror part in a first circumferential direction centering on a first axis on the reflecting surface. The tilt of the reflecting surface can be adjusted in the first circumferential direction, and the first axis is perpendicular to the axial direction along the central axis and passes through the light reflection point on the reflecting surface. Distance measuring device.
The distance measuring device according to claim 6, wherein the MEMS mirror element adjusts an inclination of the reflecting surface based on a detection result of a sensor that detects an angular velocity or an angular acceleration of the distance measuring device.
The MEMS mirror element further adjusts the tilt of the reflecting surface in the third circumferential direction by swinging the mirror portion in a third circumferential direction around the third axis on the reflecting surface. The distance measuring device according to claim 6 or 7, wherein the third axis is orthogonal to the first axis and passes through the reflection point.
The housing further includes a housing for storing the light source and the light irradiation unit, and the housing includes a light-transmitting light transmission unit having a curved part through which the light irradiated to the outside passes, The distance measuring device according to any one of claims 1 to 8, wherein the distance measuring device has an annular shape or an arc shape centered on the central axis, and an inner side surface of the curved portion facing the reflecting surface is a concave surface.
The distance measuring device according to claim 9, wherein a distance from the reflection point of the light on the reflection surface to the inner surface of the curved portion is constant.
A mobile device that travels on a road, comprising the distance measuring device according to any one of claims 1 to 10.