KR100882737B1 - 3 dimensional distance sensor and method for operating the same - Google Patents

Abstract

The present invention relates to a three-dimensional distance sensor, the scan is made in a vertical direction as well as one line scan has a feature that can measure the distance in three dimensions three-dimensional. The three-dimensional distance sensor of the present invention emits through the reflection of the mirror a reflector for reflecting the emitted light and incident light, a rotating body including a rotating means for rotating the mirror, and the emitted light used for distance measurement, And a fixed body configured to receive incident light returned from the object through reflection of the mirror, and a vertical moving body adjusting the inclination of the mirror.

Distance, sensor, measurement, mirror, three-dimensional, emission light, incident light, rotation, tilt

Description

3 dimensional distance sensor and method for operating the same}

1 is a diagram illustrating a distance sensor using two mirrors in the related art.

2 is a diagram illustrating a distance sensor using one mirror in the related art.

Figure 3 is a schematic diagram of each device of the three-dimensional distance sensor according to an embodiment of the present invention.

Figure 4 is a cross-sectional view of the three-dimensional distance sensor coupled to each other the rotating body, the fixed body, the vertical moving body according to an embodiment of the present invention.

5 is a view showing a vertical drive means implemented as an actuator according to an embodiment of the present invention.

6 is a view showing a vertical drive means implemented by a rotary motor according to another embodiment of the present invention.

7 is a diagram illustrating a distance measurement of the 3D distance sensor at a specific position according to an embodiment of the present invention.

8 is a diagram illustrating a distance measurement in a position where the mirror of the three-dimensional distance sensor is rotated 180 ° according to an embodiment of the present invention.

9 is a view showing the appearance of the emitted light and incident light when the mirror has a certain tilt (tilt) by the vertical movement of the vertical moving body according to an embodiment of the present invention.

10 is a diagram illustrating a distance measuring section for each vertical movement trajectory of the vertical moving body according to an embodiment of the present invention.

FIG. 11 is a flowchart illustrating a process of three-dimensionally measuring a distance in three dimensions by using a three-dimensional distance sensor according to an exemplary embodiment of the present invention.

12 (a) is a view showing the state of the emitted light and the incident light when using a single mirror according to an embodiment of the present invention.

12 (b) is a diagram illustrating the appearance of emitted light and incident light when using two mirrors according to another embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

300: rotating body 301: rotating motor unit

302: fixed axis 303: mirror

304: mirror mount plate 305: connecting shaft

306: hinge 307: rotary movement axis

310: fixed body 311: base

312: light emitting element 313: collimator

314: light receiving element 315: condenser lens

320: vertical moving body 321: drum

322: guide rail

The present invention relates to a distance sensor.

Existing distance sensor is generally composed of light source, rotating body, sensor, etc. When the light source emitted from the light source hits the object and returns again, the signal is detected through the sensor to determine the distance by performing a series of numerical calculations. That's the way it is. The rotating body rotates the light source and the sensor so as to perform all within a given angle range.

The conventional distance sensor has a structure in which the optical axis of the mirror coincides with the axis of the motor which rotates the mirror by using two mirrors as shown in FIG. 1.

1 (a) is a structure that can be easily configured using two mirrors 101 and 102 as an example of a conventional distance sensor, but the light path of the emitted light and the light path of the incident light are different so that there is a possibility of occurrence of a detection error. Big. In order to compensate for this, as shown in FIG. 1 (b), the beam splitter method is applied to the emission mirror and the incident light to match the optical path by using the combined light mirror 111 and the combined mirror 112. Structure. In this case, the amount of incident light decreases to about 1/4 as compared with FIG.

In order to improve the problem of using two mirrors as shown in FIG. 1, a structure using one mirror 201 as shown in FIG. 2 has been proposed. In the structure of Figure 2 by changing the mechanical structure of the optical system to use one mirror 201, to keep the light source and the sensor close to minimize the error.

However, since the mechanical structure shown in FIGS. 1 and 2 only performs a scan for one line, only the distance of the one-dimensional portion can be determined, and the three-dimensional three-dimensional distance can be measured. There is no problem.

In order to solve the above problems, an object of the present invention is to propose a mechanical structure of a distance sensor capable of measuring a distance in three dimensions and a measuring method thereof.

The three-dimensional distance sensor of the present invention emits through the reflection of the mirror a reflector for reflecting the emitted light and incident light, a rotating body including a rotating means for rotating the mirror, and the emitted light used for distance measurement, And a fixed body configured to receive incident light returned from the object through reflection of the mirror, and a vertical moving body adjusting the inclination of the mirror.

The fixture may include a condenser lens for condensing incident light reflected through the mirror, a light receiving element that senses an optical signal condensed through the condenser lens, and emits light toward the mirror by using a laser. And a collimator for converting the light emitted from the light emitting device into parallel light, and a base for fixing the light emitting device, the collimator, the light receiving device, and the condenser lens.

The fixture may include a condensing lens for condensing incident light reflected through the mirror, a light receiving element for sensing an optical signal condensed through the condensing lens, a light emitting element for emitting light using a laser; And a collimator for converting the light emitted from the light emitting device into parallel light, positioned between the mirror and the light receiving device, reflecting the emitted light emitted from the light emitting device to the mirror, and receiving incident light reflected from the mirror. And a base to fix the light incident element toward the light receiving element, and a light emitting element, a collimator, a light receiving element, a condenser lens, and a combined mirror.

In addition, the mirror is mounted by a mirror mount for fixing the mirror, the rotating means is located on the outer periphery of the fixed body and the rotational motor portion for rotational movement, fixed to connect the mirror and the rotation motor portion Include the axis.

The mirror mount may include a mirror mount plate including a plate supporting and supporting the mirror, a connecting shaft connecting the mirror mount plate to one end of the hinge, and the other end of the hinge, It includes a rotation axis of movement that moves along the guide rail is inserted into the guide rail formed in a circular groove on the inner surface.

In addition, the fixed shaft has a first fixed shaft and a second fixed shaft on both sides of a circular diameter of the mirror mount plate, respectively, and has a characteristic of supporting the mirror mount plate by connecting to the rotating motor part.

The vertical moving body may include a drum having a cylindrical shape located at an outer periphery of the rotating body, a guide rail having horizontal grooves horizontally formed on an inner surface of the drum, and vertical driving means for moving the drum up and down. Include.

In addition, the up and down drive means is characterized by being implemented as a one-dimensional actuator, and also has a feature implemented by the rotary motor by placing the rotary motor around the drum.

In addition, the measuring method of the three-dimensional distance sensor of the present invention, the first step of obtaining the distance information for one point of the three-dimensional space by emitting light through the mirror and converge it through the same mirror, and the mirror 360 A second step of acquiring distance information about one line about the horizontal axis by rotating the angle; and a third step of finally obtaining three-dimensional stereoscopic information by repeatedly performing the second step while changing the tilt of the mirror. .

Hereinafter, the detailed description of the preferred embodiments of the present invention will be described with reference to the accompanying drawings. In the following description of the reference numerals to the components of the drawings it should be noted that the same reference numerals as possible even if displayed on different drawings.

3 is a schematic view of each device of the three-dimensional distance sensor according to an embodiment of the present invention, Figure 3 (a) is a view showing a rotating body 300 for rotating a mirror (mirror), Figure 3 (b) FIG. 3 is a view showing a fixture 310 for processing emitted light and incident light, and FIG. 3 (c) is a view showing a vertical moving body 320 for moving a mirror up and down. 4 is a cross-sectional view of a three-dimensional distance sensor in which the rotating body 300, the fixing body 310, and the vertical moving body 320 are coupled to each other according to an embodiment of the present invention.

The emitted light emitted by the light emitting element 314 in the fixture 310 is reflected by a specific object and returned as incident light. The present invention provides a structure in which the mirror 303 can have a predetermined tilt as well as 360 degree rotation. Thus, the distance can be measured three-dimensionally. To this end, the mirror 303 may be rotated 360 degrees by the rotating body 300, and may also be moved up and down by the vertical moving body 320.

First, the structure of the rotor 300 of FIG. 3 (a) will be described. The rotor includes a mirror 303, a mirror mount 304, 305, 306, 307, and a rotation means 301, 302. The mirror 303 reflects the light emitted from the light emitting element 312 of the fixture 310 to the outside, and reflects the light coming back to the external object by the emitted light as incident light to the condensing lens 315. Perform the send function. Therefore, since the light is emitted through the same mirror 303 and converged again through the same mirror, accurate measurement is possible.

The mirror mounts 304, 305, 306, 307 fix the mirror to serve as a support, and the mirror mount is composed of a mirror mount plate 304, a connection shaft 305, and a rotation movement shaft 307. The mirror mount plate 304 is implemented as a plate supporting and supporting the mirror 303, and the connecting shaft 305 connects the mirror mount plate 304 to one end of the hinge 306. The rotational movement shaft 307 is connected to the other end of the hinge 306 and is inserted into a guide rail 322 formed as a circular groove on the surface of the vertical moving body 320, thereby providing the guide rail 322. Move along the rotation.

Therefore, when there is rotation of the rotating body 300, the mirror 303 connected to the fixed shaft 302 is rotated along the guide rail 322 in the vertical moving body 320. In addition, when the vertical moving body 320 moves up and down, the mirror mount plate 304 to which the mirror 303 is attached moves up and down inclined at a constant tilt by the rotation of the hinge 306.

The rotating means includes a rotating motor unit 301 and a fixed shaft 302, which rotates the mirror 303 on the upper part of the fixture. The rotation motor unit 301 rotates the mirror 303 by 360 degrees. For this purpose, the mirror motor unit 301 and the mirror mount plate 304 are connected by the fixed shaft 302. As shown in FIG. 4, the fixed shaft 302 is connected to both surfaces of the circular surface diameter of the mirror mount plate 304 by the first fixed shaft 302a and the second fixed shaft 302b, respectively. Support 304. Therefore, the mirror 303 rotates 360 degrees along the rotational movement shaft 307 inserted into the guide rail 322 by the rotation of the rotary motor unit 301. In addition, the mirror 303 has a vertical tilt of a predetermined tilt around the first fixed shaft 302a and the second fixed shaft 302b by the vertical movement of the vertical moving body 320.

Referring to the structure of the fixture 310 of Figure 3 (b), the fixture 310 is a light receiving element 314 for sensing the incident optical signal as incident light, by condensing the incident optical signal to the light receiving element A focusing lens 315, a light emitting device 312 emitting light (light) using a laser, and a collimator 313 for converting the laser light emitted from the light emitting device 312 into parallel light. a collimator and a base 311 for fixing the light receiving element 314, the condenser lens 315, the light emitting element 312, and the collimator 313. The collimator 313 is located above the light emitting device 312 as an optical device for forming parallel light.

Light emitted from the light emitting device 312 is converted into parallel light through the collimator 313, reflected by the mirror 303, and emitted as signal light to the outside. At this time, the point at which the light is emitted varies depending on the rotational position and the tilt of the mirror 303. When the emitted light hits an object and returns as signal light, the signal light is reflected by the mirror 303 and is incident on the light receiving element 314 through the condenser lens 315.

First, the structure of the vertical moving body 320 of FIG. 3 (c) will be described. The vertical moving body 320 has a cylindrical drum 321 and a circular groove formed horizontally on the inner surface of the drum 321. It consists of a guide rail 322 and a vertical driving means (not shown) for moving the drum 321 up and down. The guide rail 322 has a rotary shaft 307 for connecting the mirror mount plate 304 is inserted, the rotary shaft 307 is guide rail 322 in accordance with the rotation of the rotating body 300 It can rotate 360 degrees along.

The drum 321 is moved up and down by the operation control of the vertical drive means, this vertical drive means can be implemented in two ways. One is implemented using a one-dimensional actuator 501 as shown in Figure 5 and the other is implemented by applying a rotary motor 601 as shown in FIG.

In the one-dimensional actuator 501 of FIG. 5, a linear actuator is disposed below the vertical moving body 320 to move the drum up and down by the operation of the actuator. The one-dimensional actuator 501 is able to move the drum up and down by pushing the drum up or down by using the electric magnetic field or the force of the vacuum.

In the method using the rotary motor of FIG. 6, the rotary motor 601 is positioned around the vertical moving body 320, and a rail of a threaded shape is disposed on the inner surface of the rotary motor 601, and according to the rotation of the rail. The drum of the up and down moving body 601 is bitten by the rail can be implemented to move up and down.

As described above, the three-dimensional distance sensor consisting of the rotating body 300, the fixed body 310, the vertical moving body 320, the rotation of the mirror 303 and the tilt of the mirror 303 can be made free, three-dimensional three-dimensional You can measure the distance. 7 and 8 illustrate the state of the emitted light and the incident light according to the rotation of the mirror 303, and the state of the emitted light and the incident light according to the vertical movement of the mirror 303.

FIG. 7 is a view illustrating a distance measurement of a 3D distance sensor at a specific position according to an embodiment of the present invention, and FIG. 8 is a position where the mirror of the 3D distance sensor is rotated 180 ° from the position point of FIG. 7. Figure shows the distance measurement in.

Referring to FIG. 7, the emitted light 701 emitted from the light emitting device is emitted to the right through the mirror, and thus, incident light 702 enters from the right and enters the light receiving device via the mirror. On the other hand, when the mirror is rotated by 180 ° due to the movement of the rotating body as shown in FIG. 8, the emitted light 801 emitted from the light emitting element is emitted to the left through the mirror, and thus their incident light 802 from the left side. ) Enters through the mirror and enters the light receiving element.

FIG. 9 is a view showing the state of the emitted light and the incident light when the mirror has a certain tilt due to the vertical movement of the up and down moving body. The mirror basically has a 45 ° tilt as shown in FIG. 9 (b). In this state, when the vertical moving body 320 moves downward as shown in FIG. 9 (a), the vertical moving body 320 has a larger inclination than the basic inclination of 45 ° by the rotation of the hinge 306 connected to the guide rail. Likewise, when the vertical moving body 320 moves upward as shown in FIG. 9 (c), the vertical moving body 320 has a smaller tilt than 45 °, which is a basic tilt by the rotation of the hinge 306 connected to the guide rail. The inclination range of the mirror preferably has a range of ± 10 ° rather than the reference inclination of 45 °.

The distance measurement section for each vertical movement trajectory of the up and down moving body is illustrated in the graph of FIG. 10, and the tilt change operation of the mirror is performed in an idle range in which distance measurement is not performed during mirror rotation. That is, when there is rotation of the mirror opposite to the measurement direction during the measurement, the inclination of the mirror is changed in the idle section.

FIG. 11 is a flowchart illustrating a process of three-dimensionally measuring a distance in three dimensions by using a three-dimensional distance sensor according to an exemplary embodiment of the present invention.

To measure the distance in three dimensions in relation to a specific object, measure the distance about one line around the horizontal axis of the object (S1104), and then rotate the rotating body while continuously changing the tilt of the mirror (S1106). (S1104), it is possible to obtain desired three-dimensional distance information.

In detail, first, a step (S1102) of obtaining distance information on a point of an object is obtained. Looking at the state of obtaining the distance information for the point, the light emitting device 312 in the three-dimensional distance sensor of the present invention emits the laser light as the emission light and the collimator 313 converts the laser light into parallel light. . The laser light that reaches the object is scattered or reflected back from the surface of the object and part of the light is returned to the three-dimensional distance sensor. The light returned to the three-dimensional distance sensor is reflected by the mirror 303 and then focused on the light receiving element 314 via the condenser lens 315. The focused signal from the light receiving element 314 is sensed and transferred to the computing device of the system. In this manner, distance information on one point of the three-dimensional space is obtained. As described above, by emitting light through the same mirror 303 and converging it through the same mirror, a measurement error rate may be reduced.

After obtaining the distance information for one point of the three-dimensional space as described above (S1102) by rotating the rotating body by rotating the mirror 360 ° to obtain a distance for one line around the horizontal axis (S1104). That is, whenever there is a rotation of the mirror by a predetermined angle (for example, 1 ° of the mirror), the step S1102 is repeated for each unit to measure the distance of one line around the horizontal axis. At this time, the mirror is rotated by the rotation of the rotating motor unit connected to the mirror and the fixed shaft, the mirror is rotated, along the axis connected to the guide rail formed on the drum inner surface surrounding the outside of the mirror Rotate 360 °.

After the distance measurement for one line is completed, the mirror tilt is continuously changed step by step using the up and down moving object (S1106), and the distance information in one line is performed by performing the step S1104 in the tilt step of the mirror. Acquire. The inclination change of the mirror is a hinge is connected to the vertical movable body that can move up and down, the tilt change is made by the vertical movement of the vertical movable body. At this time, when the tilt change of the mirror is made, the tilt change operation of the mirror is performed in an idle range in which distance measurement during mirror rotation is not made.

As a result, by rotating the rotating body while continuously changing the position of the up and down moving object until the mirror reaches the maximum inclination that can be inclined (S1108), step S1104 and S1106 are performed, resulting in three-dimensional stereoscopic distance information ( S1110) can be made.

Meanwhile, in the present invention, as shown in FIG. 12 (a) of the fixed body 310, the emitted light emitted from the light emitting device 312 is emitted to the right through the mirror 303, and the emitted light is reflected by the object to incident light. As a result, it has a structure of returning back to the light receiving element 314 through the condenser lens 315 through the same mirror 303, and measuring the distance in three dimensions three-dimensionally according to the vertical tilt change of the mirror and the 180 ° rotation change of the mirror. Can be.

By the way, the fixture 310 of the present invention can not only measure the distance in three dimensions by using a single mirror 303, as shown in Figure 12 (a), but also as another embodiment of the present invention As shown in b), even when the light path of the emission light and the light path of the incident light are coincided with each other using two mirrors 1201 and 1202, the distance can be measured in three dimensions. That is, as shown in FIG. 12 (b) of the fixed body 310, the emission light and the incident light are formed by using the light transmission mirror 1201 and the combined mirror 1202 by applying a beam splitter method. Under the structure of matching, the distance can be measured three-dimensionally in three-dimensional manner according to the vertical tilt change of the light transmission mirror 1201 and the 180 ° rotational change of the light transmission mirror like the mirror 303. The light transmission mirror 1201 is the same as the mirror 303 of FIG. 12 (a) which reflects the emitted light and the incident light, but differs only in name. If there is a difference, the mirror 303 of FIG. 12 (a) has a different light path of the emitted light and the incident light, but the light transmission mirror 1201 of FIG. 12 (b) has the same light path of the emitted light and the incident light.

As described above, matching the optical paths of the emitted light and the incident light reflected by the transmissive mirror 1201 is performed by the combined mirror 1202 between the transmissive mirror 1201 and the light receiving element 314. 1202 is a polarizing mirror and is installed to have a predetermined slope between the light receiving element 314 and the combined mirror 1202. In addition, the light emitting device 312 is provided to have a structure that emits light in parallel toward the combined mirror 1202 rather than the upper side.

The light emitted from the light emitting device 312 is reflected by the combined mirror 1202 by the collimator 313 to the transmission mirror 1201, and the reflected light is reflected back from the transmission mirror 1201 and is emitted as external light. Is released on. The incident light reflected by the emitted light reflected on the object to be measured is reflected from the transmissive mirror 1201 toward the combined mirror 1202, and the combined mirror transmits the reflected light to the light receiving element 314 as it is.

In the above description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the scope of the present invention is not to be determined by the embodiments described above, but will be apparent in the claims as well as equivalent scope.

Compared to the conventional method of performing one-dimensional distance measurement by scanning only one line, the present invention has an effect that distance measurement with respect to three-dimensional space can be made by rotating the lens at an angle in the vertical direction.

Claims (15)

A rotating body including a mirror supported by the mirror mount to reflect the emitted light and the incident light, and a rotating means for rotating the mirror; A fixture for emitting emission light used for distance measurement through reflection of the mirror and receiving incident light returning from the object through reflection of the mirror; A circular groove is formed horizontally on the inner surface of the drum outside the rotating body and the end of the mirror mount is inserted to adjust the tilt of the mirror. 3D distance sensor comprising a. The method of claim 1, wherein the fixing body, A condenser lens for condensing incident light reflected through the mirror; A light receiving element configured to sense an optical signal focused through the condenser lens; A light emitting device emitting light toward the mirror using a laser; A collimator for converting light emitted from the light emitting device into parallel light; A base for fixing the light emitting element, collimator, light receiving element, and condenser lens 3D distance sensor comprising a. The method of claim 1, wherein the fixing body, A condenser lens for condensing incident light reflected through the mirror; A light receiving element configured to sense an optical signal focused through the condenser lens; Light emitting device for emitting light using a laser; A collimator for converting light emitted from the light emitting device into parallel light; A combined mirror positioned between the mirror and the light receiving element to reflect the emitted light emitted from the light emitting element to the mirror, and incident light reflected from the mirror to the light receiving element; Base for fixing the light emitting element, collimator, light receiving element, condenser lens, combined mirror 3D distance sensor comprising a. delete According to claim 1, The rotating means, A rotary motor unit positioned around the outer periphery of the fixed body and rotating; Fixed shaft connecting the mirror and the rotary motor unit 3D distance sensor comprising a. The method of claim 1, wherein the mirror mount, A mirror mount plate comprising a plate supporting and supporting the mirror; A connecting shaft connecting the mirror mount plate to one end of a hinge; A rotational shaft connected to the other end of the hinge and inserted into a guide rail formed in a circular groove on a surface of the vertical moving body and moving along the guide rail; 3D distance sensor comprising a. 6. The three-dimensional distance of claim 5, wherein the fixed shaft is connected to the rotating motor part as a first fixed shaft and a second fixed shaft on both sides of a circular diameter of the mirror mount plate, respectively. sensor. According to claim 1, The vertical moving body, A drum having a cylindrical shape located around the outer periphery of the rotating body; A guide rail having a circular groove horizontally formed on an inner surface of the drum; Vertical drive means for moving the drum up and down 3D distance sensor comprising a. The three-dimensional distance sensor according to claim 8, wherein the vertical driving means is implemented by a one-dimensional actuator. The three-dimensional distance sensor of claim 8, wherein the up and down driving means is implemented by the rotating motor by placing a rotating motor around the drum. A first step of obtaining distance information on one point of the three-dimensional space by emitting light through the mirror and converging it through the same mirror; A second step of obtaining distance information about one line about a horizontal axis by rotating the mirror 360 degrees along an axis connected to a guide rail formed on an inner surface of a drum surrounding the outer surface of the mirror; A third step of finally obtaining three-dimensional stereoscopic information by repeatedly performing the second step while changing the tilt of the mirror; 3D distance sensor measuring method comprising a. 12. The method of claim 11, wherein the third step comprises changing a tilt of the mirror in an idle range in which distance measurement during mirror rotation is not performed. 12. The method of claim 11, wherein in the second step, the mirror is rotated by the rotation of the rotating motor unit connected to the mirror with the fixed shaft. delete 12. The method of claim 11, wherein the third step includes a mirror hinged to a vertically movable body that is movable up and down, and the tilt is changed by vertically moving the vertically movable body.

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