KR102577079B1 - 3 dimensional scanning device using cone shape rotation with coaxial mirror - Google Patents

Abstract

The present invention relates to a three-dimensional scanning device, which includes a lower reflector unit that changes the path of laser light transmitted from a light source and reflects it, a lower body unit that rotates the lower reflector unit, and a device that reflects the laser light transmitted from the lower reflector unit. It includes an upper reflector unit that rotates the upper reflector unit, and an upper body unit that rotates the upper reflector unit, wherein the lower reflector unit includes a pair of lower mirrors arranged to be spaced apart from each other, and each of the pair of lower mirrors is separated from the rotation axis of the lower reflector unit. They are disposed at different separation distances to form a conical rotating light path between the lower reflector and the upper reflector during irradiation of the laser light and rotation of the lower reflector, and the upper body rotates the upper reflector and It includes an upper driving part that is stacked and disposed on the upper side of the lower driving part, and the upper driving part is formed of a hollow motor, so that there is no need for a complicated structure such as installing multiple lasers or multiple motors. Since a cone-shaped rotating beam can be formed using a rotating method, it is possible to easily scan an area in the vertical direction while rotating 360°, and the connecting wire for driving the upper reflector prevents the scanning beam from being blocked. A LiDAR scanning device capable of 3D scanning can be provided.

Description

3D scanning device using coaxial mirror double rotation method {3 DIMENSIONAL SCANNING DEVICE USING CONE SHAPE ROTATION WITH COAXIAL MIRROR}

The present invention relates to a three-dimensional scanning device, and more specifically, to a coaxial mirror double rotation type three-dimensional scanning device that can easily scan an area in the vertical direction using two rotating reflectors arranged to face each other. will be.

In general, LiDAR (Light Detection And Ranging, LiDAR) detects the presence of a specific object or obstacle by firing a laser to reach a specific target and measuring the distance by calculating the time for the laser to reflect or scatter and return. This is a sensor for

These LIDARs are often called laser radars or 3D scanners because the means for detecting objects and measuring distances is lasers. Compared to radar, the use of lasers with short wavelengths instead of electromagnetic waves increases measurement precision and allows accurate identification of surrounding information, making it applicable to autonomous driving systems, which have recently become an issue.

Conventional scanning lidar radiates a laser in a fixed, specific direction and then rotates 360 degrees to obtain scanning information for a designated area, so there is a problem with limitations in the measurement area.

As a way to solve this problem, there is a method of obtaining scanning information by radiating several lasers in each specific direction to obtain information about multiple vertical directions. However, in this method, vertical direction information of a large area is obtained. In order to obtain scanning information, at least 4 to 64 lasers are stacked vertically to obtain scanning information. Therefore, the use of multiple lasers and light receivers increases the manufacturing cost and makes the implemented structure complicated. There is.

In addition, as a method to obtain information about the vertical direction, a motor that rotates the light source or mirror 360° and a motor that moves the light source or mirror in the up and down directions are installed, and the light source or mirror is rotated up and down by the two motors. A method has been proposed to obtain information about the vertical or vertical direction by moving in one direction.

However, the structure of moving up and down while rotating by two motors not only makes the structure of the device complicated and expensive to manufacture, but also has the problem of deteriorating the durability of the device because the device itself must be mechanically rotated.

In addition, a method of acquiring information in the vertical direction has been proposed as a way to expand the scanning area using a diffusion lens. However, in the case of LiDAR devices, there is a problem in that the measurement distance is reduced due to the diffusion of the laser.

On the other hand, when performing 3D scanning using two rotating reflectors arranged to face each other, each driving unit must be installed to rotate the upper and lower rotating reflectors. In order to drive the upper and lower driving units, power must be supplied to each driving unit. There is no choice but to deploy a front line that does this.

When installing such a power supply wire, the connection wire for supplying power to the upper drive unit must be installed up and down across the frame or protective tube, so there was a problem in that the scanning beam was obscured by the connection wire.

Korean Patent No. 10-1903960 (LiDAR device)

The present invention aims to solve the problems of the prior art described above. The purpose of the present invention is to easily scan the area in the vertical direction by converting the light beam into a cone-shaped rotating beam through reflectors disposed at the top and bottom, while driving the reflector at the top. The aim is to provide a LiDAR scanning device capable of 3D scanning that can prevent the scanning beam from being obscured by the connecting wire.

Another object of the present invention is to provide a LiDAR scanning device capable of 3D scanning that has a simple structure and can be miniaturized by enabling easy scanning of an area in the vertical direction even when using a single light source.

In order to achieve the above-mentioned object, the three-dimensional scanning device of the coaxial mirror double rotation method according to the present invention includes a lower reflector portion that changes the path of the laser light transmitted from the light source and reflects it, a lower body portion that rotates the lower reflector portion, and , an upper reflector portion that reflects the laser light transmitted from the lower reflector portion, and an upper body portion that rotates the upper reflector portion, wherein the lower reflector portion includes a pair of lower mirrors arranged to be spaced apart from each other, and Each of the pair of lower mirrors is disposed at different distances from the rotation axis of the lower reflector unit, forming a conical rotating light path between the lower reflector unit and the upper reflector when the laser light is irradiated and the lower reflector unit rotates, The upper main body includes an upper driving part that rotates the upper reflector and is stacked on an upper side of the lower driving part, and the upper driving part is formed of a hollow motor.

Here, the upper main body further includes a cylindrical protective tube on one side of which is inserted into the hollow of the upper driving unit and on the other side of which the upper reflector is attached.

Here, the upper body portion is characterized in that an inclined surface on which the upper reflector portion is installed is formed.

Here, the pair of lower mirrors includes a first lower mirror disposed close to the rotation axis of the lower reflector portion and a second lower mirror disposed close to the outer peripheral surface of the lower reflector portion.

Here, the first lower mirror and the second lower mirror are installed at different inclination angles with respect to the horizontal plane, and the upper reflector portion is disposed inclined with respect to the horizontal plane.

Here, the lower body portion includes a light source portion that irradiates laser light, an optical path portion that transmits the laser light irradiated from the light source portion, and a lower driving portion that rotates the lower reflector portion and is formed with a hollow portion through which the laser light passes. It is characterized by

Here, the lower reflector portion is formed of a pentaprism having two reflecting surfaces in place of a pair of lower mirrors, and the pentaprism is eccentrically disposed with respect to the central axis of the lower reflector portion to irradiate the laser light and the lower reflector. A conical rotating light path is formed between the pentaprism and the upper reflector when the unit rotates.

Here, the upper reflector portion is characterized in that it is a right-angled prism installed to replace the upper reflector.

According to the present invention having the above-described configuration, a conical turning beam is generated in a double turning method through reflectors arranged up and down, without the need for a complicated structure such as installing a plurality of lasers or a plurality of motors as in a conventional lidar scanning device. Since it can be formed, it can easily scan the area in the vertical direction while rotating 360°, and can prevent the scanning beam from being blocked by the connection wire for driving the upper reflector. A LIDAR scanning device may be provided.

In addition, according to the present invention, not only is it possible to implement it economically at a low cost because it does not use an optical lens, but it is also economical because it does not require expensive parts such as slip rings because the electrical components do not rotate and only the upper and lower reflectors rotate. A simple 3D scanning device can be provided.

In addition, according to the present invention, even if a single light source is used, an area in the vertical direction can be easily scanned, and the upper and lower reflectors can be rotated at high speed, so ultra-high-speed scanning is possible, and a 3D scan with a simple structure and miniaturization is possible. A LIDAR scanning device may be provided.

Figure 1 is a diagram schematically showing a coaxial mirror double rotation type 3D scanning device according to the present invention.
2A and 2B are diagrams showing an example of the lower reflector portion of the present invention.
3A and 3B are diagrams showing an example of the upper reflector portion of the present invention.
Figure 4 is a diagram explaining the path of the cone-shaped turning light beam of the present invention.

Hereinafter, a three-dimensional scanning device using a coaxial mirror double rotation method according to the present invention will be described in detail as an example with reference to the attached drawings.

As shown in Figures 1 to 4, the three-dimensional scanning device 1 according to the present invention includes an upper body portion 10, a protective barrel 12, a lower body portion 30, and an upper reflector portion 20. ) and a lower reflector portion 50.

The upper body portion 10 is configured to rotate the upper reflector portion 20.

In this embodiment, the upper body portion 10 includes an upper driving portion 11 and a protective barrel 12.

Since the connection wire for supplying power to the upper drive unit must be installed up and down across the protective tube, the scanning beam is blocked by the connection wire. The scanning device according to this embodiment uses the connection wire described above. It is composed of an unformed structure.

As shown in FIG. 1, the upper driving unit 11 is stacked and disposed above the lower driving unit 32. The upper driving part 11, like the lower driving part 32, is formed of a hollow motor having a hollow shaft.

The upper main body is provided with a cylindrical protective barrel (12).

The protective barrel 12 preferably has both inner and outer surfaces made of non-reflective coating and is made of a material with high infrared transmittance and mechanical strength, so that it can withstand heat generation and temperature rise due to high-speed rotation of the reflector.

In addition, the protective barrel 12 is formed as a spherical barrel or a cylindrical barrel, and the interior is maintained in a vacuum or filled with an inert gas (e.g., nitrogen) to prevent temperature rise and aging oxidation of the reflector surface. It is desirable.

The lower part of the protective barrel 12 is inserted into the hollow shaft of the upper driving unit 11, is connected to the upper driving unit 11 via a bearing, and is rotated by the upper driving unit. In addition, an inclined surface 13 is formed on the upper surface of the protective barrel 12, and the upper reflector unit 20 is attached to the inner surface of the inclined surface.

By the above-described configuration, the lower driving part and the upper driving part, each composed of a hollow motor, are rotated and driven, respectively, so that the lower reflector part and the upper reflector part can be rotated, respectively, and at the same time, the connecting wire as described above can be omitted. .

An upper reflector portion 20 is installed in the upper body portion.

As shown in FIG. 3A, the upper reflector portion 20 is installed as a reflector and is disposed at an angle with respect to the horizontal plane to reflect the laser light transmitted from the lower reflector portion toward the light irradiation object. In this embodiment, the upper reflector unit 20 is disposed inclined at 45° with respect to the horizontal plane, but the inclination angle is not necessarily limited to this and the inclination angle is changed to an angle of 45 degrees or less so that the high-low angle scan range looks slightly downward. You can also configure it.

A lower body portion 30 that rotates the lower reflector portion 50 is installed on the lower side of the upper body portion 10.

The lower body portion 30 includes a light source portion 31 and a lower driving portion 32.

The light source unit 31 generates and irradiates laser light for scanning the distance measurement object. The optical path unit 31a connected to the light source unit 31 forms an optical path that transmits the laser light emitted from the light source unit. The optical path portion 31a is formed in a substantially hollow cylindrical shape. An optical path change mirror 34 is installed at the end of the optical path portion 31a.

The optical path change mirror 34 is installed at the end of the optical path unit and is installed at an angle of approximately 45° with respect to the optical path of the optical path unit, so as to reflect the laser light irradiated from the light source unit 31 to the bottom. It is configured to reflect toward the neck 50.

A lower driving unit 32 is installed on the optical path change mirror and the upper part of the optical path unit. The lower driving unit 32 is composed of a hollow motor having a hollow shaft in the center and a hollow rotor provided around the hollow shaft. The laser light whose path has been changed by the optical path change mirror 34 passes through the hollow part of the lower driving part and is transmitted to the lower reflector part 50.

As a result, the optical path of the optical path unit can be easily secured and the overall configuration of the lower driving unit and the lower main body can be configured simply.

A lower reflector unit 50 is installed on the upper part of the lower body unit.

The lower reflector unit 50 includes a pair of lower mirrors 51 and 52, and the pair of lower mirrors 51 and 52 are installed on the upper part of the lower reflector support body 50a.

The lower reflector support 50a of the lower reflector unit is fastened to the inside of the lower drive unit 32 via the lower bearing 33, and the lower reflector support body is rotated by the rotational drive of the lower drive unit 32.

Each of the pair of lower mirrors is disposed at different distances from the rotation center axis of the lower reflector unit 50. As shown in FIG. 2A, the first lower mirror 51 is disposed close to the rotation axis of the lower reflector portion, and the second lower mirror 52 is disposed close to the outer peripheral surface of the lower reflector portion.

Additionally, the first lower mirror 51 and the second lower mirror 52 are installed at different inclination angles with respect to the horizontal plane.

As shown in Figures 1 and 4, the laser light irradiated from the horizontally irradiated light source is reflected by the optical path change mirror to change the optical path in the vertical direction, and the laser light irradiated in the vertical direction is reflected by the optical path change mirror. After passing through the hollow part of the driving unit, it is reflected by the first lower mirror 51 disposed close to the central axis of the lower reflector unit and transmitted to the second lower mirror 52. The laser light irradiated toward the second lower mirror 52 is irradiated at an angle α toward the upper reflector portion 20 by the second lower mirror 52 disposed at an angle with respect to the horizontal plane.

When the lower reflector unit configured as described above rotates at a speed w1, as shown in FIGS. 2A and 4, the laser light is reflected from the second lower mirror 52 and irradiated to the upper reflector unit 20. Forms a conical rotating ray path having an angle α with respect to the upper reflector portion.

As shown in FIGS. 3A and 4, the laser light forming a conical rotating beam path is reflected by the upper reflector unit 20 rotating at high speed while inclined at 45 degrees with respect to the horizontal plane, and the elevation angle of ψ and θ It is irradiated with an azimuth angle of , and a cone-shaped rotating ray is irradiated with respect to the scan target surface, enabling scanning of the area in the vertical direction.

Here, the scanning range of the scan target surface can be adjusted by adjusting the installation position of the second lower mirror 52, the installation angle of the first and second lower mirrors, and the installation angle of the upper reflector unit.

Meanwhile, the lower reflector portion and the upper reflector portion may be rotated at different speeds.

When the lower reflector unit 50 is driven for one rotation, a cone-shaped rotating light beam is generated once per cycle, enabling scanning of the upper and lower areas, respectively. Here, the rotation speed of the lower mirror unit can be adjusted according to the number of scans per rotation of the lower reflector unit, and the rotation speed of the upper reflector unit can be adjusted according to the rotation speed of the lower reflector unit. The same scan resolution can be achieved by lowering the rotation speed of the lower reflector unit and increasing the rotation speed of the upper reflector unit.

As described above, according to the scanning device of the present invention, an area in the vertical direction can be easily scanned while rotating 360° using the lower reflector without the need for a complicated structure such as installing multiple lasers or multiple motors. . In addition, the scan resolution can be adjusted by adjusting the rotation speed of the lower reflector unit and adjusting the rotation speed of the upper reflector unit in accordance with the rotation speed of the lower reflector unit.

Meanwhile, the lower reflector portion may be formed of a pentaprism 53 as shown in FIG. 2B instead of a pair of lower mirrors as shown in FIG. 2A.

The pentaprism 53 is constructed by coating two surfaces of the pentaprism so as to have two reflecting surfaces 54, and is disposed eccentrically with respect to the central axis of the lower reflector portion.

As shown in FIG. 2, the eccentrically arranged pentaprism 53 is configured such that the laser light reflected through the reflective surface 54 is irradiated toward the upper reflector portion 20 at an angle of α. , when rotating at a speed of w1, it is configured to form a conical turning light path having an angle of α with respect to the upper reflector portion.

Additionally, the upper reflector portion may be formed of a right-angled prism 21 installed to replace the upper reflector, as shown in FIG. 3B.

As described above, by forming the lower reflector portion as a pair of lower mirrors or a pentaprism and forming the upper reflector portion as a reflector or a straight prism, the upper and lower reflector portions can be formed in a plurality of combinations.

That is, the lower part is composed of a pair of mirrors and the upper part is a reflector, the lower part is composed of a pentaprism and the upper part is a reflector, the lower part is composed of a pair of mirrors and the upper part is composed of a right-angled prism, or the lower part is composed of a pair of mirrors and the upper part is composed of a right-angled prism. It is composed of a pentaprism and the upper part is composed of a right-angle prism, so it can be easily installed in an appropriate configuration as needed.

This embodiment only clearly shows part of the technical idea included in the present invention, and modifications and specific embodiments that can be easily inferred by a person skilled in the art within the scope of the technical idea included in the specification of the present invention are It is obvious that all are included in the technical idea of the present invention.

1: Coaxial mirror double rotation type scanning device
10: upper body part
20: upper reflector part
30: lower body part
50: lower reflector part

Claims (8)

A lower reflector that changes the path of the laser light transmitted from the light source and reflects it,
A lower body portion that rotates the lower reflector portion,
an upper reflector portion that reflects the laser light transmitted from the lower reflector portion,
It includes an upper body portion that rotates the upper reflector portion,
The lower reflector unit includes a pair of lower mirrors arranged to be spaced apart from each other, and each of the pair of lower mirrors is arranged at different distances from the rotation axis of the lower reflector unit, so that irradiation of the laser light and rotation of the lower reflector unit occur. Forming a conical rotating ray path between the lower reflector and the upper reflector,
The upper body part is stacked and disposed on an upper side of a lower driving part that rotates the lower reflector unit, and includes an upper driving part that rotates the upper reflector unit.
According to claim 1,
The upper driving part is formed of a hollow motor,
The upper main body further includes a cylindrical protection tube on one side of which is inserted into the hollow of the upper driving part and on the other side of which the upper reflector is attached.
According to claim 2,
A coaxial mirror double rotation type three-dimensional scanning device, characterized in that an inclined surface on which the upper reflector portion is installed is formed in the upper body portion.
According to claim 1,
The pair of lower mirrors,
a first lower mirror disposed close to the rotation axis of the lower reflector unit;
A coaxial mirror double rotation type three-dimensional scanning device comprising a second lower mirror disposed close to the outer peripheral surface of the lower reflector portion.
According to claim 4,
The first lower mirror and the second lower mirror are installed at different inclination angles with respect to the horizontal plane,
A coaxial mirror double rotation type three-dimensional scanning device, wherein the upper reflector portion is disposed at an angle with respect to the horizontal plane.
According to claim 1,
The lower main body,
A light source unit that irradiates laser light,
an optical path unit transmitting laser light emitted from the light source unit;
A three-dimensional scanning device of a coaxial mirror double rotation type, characterized in that it includes a lower driving part that rotates the lower reflecting mirror and has a hollow part through which the laser light passes.
According to claim 1,
The lower reflector portion is formed of a pentaprism having two reflecting surfaces, replacing a pair of lower mirrors,
The pentaprism is disposed eccentrically with respect to the central axis of the lower reflector portion,
A three-dimensional scanning device of a coaxial mirror double rotation type, characterized in that a conical rotating light path is formed between the pentaprism and the upper reflector when the laser light is irradiated and the lower reflector is rotated.
According to claim 1,
A coaxial mirror double rotation type three-dimensional scanning device, wherein the upper reflector unit is a right-angled prism installed in place of the upper reflector.

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