KR20170031901A - Scanning Method Using High Speed Scanning Device - Google Patents

Abstract

According to an embodiment of the present invention to solve the above mentioned problem, the present invention relates to a scanning method using a high speed scanning device, comprises: a step of obtaining an image of a specific area by using a vision sensor; a step of extracting a target object from the obtained image to set a scan area; a step of calculating a rotation angle for performing scanning by restricting within the scan area; a step of rotating an optical scanner for performing the scanning according to the calculated rotation angle; and a step of obtaining distance information of the target object by the optical scanner. More specific details of the present invention are included in the description and drawings of the specification.

Description

[0001] The present invention relates to a scanning method using a high-speed scanning device,

The present invention relates to a scanning method using a high-speed scanning apparatus, and more particularly, to a scanning method using a high-speed scanning apparatus, in which a region to be scanned by a vision is first determined and a fast scanning can be performed. Further, The present invention relates to a scanning method using a high-speed scanning device capable of performing scanning more quickly since Lada can start scanning immediately after shooting a vision image.

LIDAR (Laser Detection And Ranging) is a radar system that shoots laser pulses and measures the position coordinates of the object by measuring the time of reflection and return. Although the accuracy of object discrimination is somewhat low, Rada utilizes the ability to generate pulse signals of high energy density and short cycle, and is used in various fields such as more precise observation of the physical properties in the atmosphere and distance measurement.

Vision, on the other hand, is a device that gives visual and judgment functions to a machine. By capturing an image using an image sensor, the hardware and software systems recognize and recognize the object. Vision transforms three-dimensional space into two-dimensional image information, so additional sensors or stereo cameras are required to measure distances, and it is difficult to measure distances by itself. However, the ability to recognize and extract objects from captured images is excellent.

Recently, a technique has been proposed to improve both object recognition and distance measurement capability by combining Lada and vision. Particularly, it is utilized for Forward Collision Warning System (FCW) and avoidance obstacle and speed control in unmanned vehicle driving, so active research and development are being carried out in the field.

However, in the past, Lada and Vision operated independently, and distance information was obtained in Lida. In Vision, image information was obtained, and then information and distance were measured by synthesizing and analyzing the information obtained separately. Therefore, it took a lot of time for object recognition and distance measurement. Particularly, when a single Lada is used, the entire circumference is rotated 360 degrees and scanned. Even if only the front side is scanned, all the areas included in a predetermined viewing angle are scanned.

Korean Patent No. 1302944 Korean Laid-Open Publication No. 2014-0004413

SUMMARY OF THE INVENTION It is an object of the present invention to provide a scanning apparatus and a scanning method capable of improving both object recognition and distance measuring ability by combining vision with a lidar, Method.

Also, the present invention provides a scanning method using a high-speed scanning device that shortens the scanning time of the imaging lens by making the vision and the imaging lens rotate together, .

The problems of the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided a scanning method using a high-speed scanning apparatus, including: acquiring an image of a specific region using a vision sensor; Extracting an object from the acquired image and setting a scan area; Calculating a rotation angle for performing scanning only within the scan area; Rotating the optical scanner that performs the scanning according to the calculated rotation angle; And acquiring distance information of the object by the optical scanner.

Other specific details of the invention are included in the detailed description and drawings.

The embodiments of the present invention have at least the following effects.

By combining Lada with vision, both object recognition and distance measurement capabilities are improved. At the same time, vision recognizes and extracts objects in the area. By limiting the scan area of Lada, Lada scans only objects that are limited by vision The scanning time can be shortened.

In addition, since the vision and the lidar are fixed and rotated together, when the region is photographed by the vision, the lidar is directed in the same direction as the vision, and after the image of the vision, the lidar can perform the scanning without additional rotation of the lidar The scanning time can be further shortened.

In addition, if the scanning time of the Lada is shortened by the above-described method, it is possible to acquire data of a fast, more precise and high resolution.

The effects according to the present invention are not limited by the contents exemplified above, and more various effects are included in the specification.

1 is a block diagram of a scanning method using a high-speed scanning apparatus 1 according to an embodiment of the present invention.
2 is a reference view showing the basic principle of LIDAR in the optical scanner 11 according to an embodiment of the present invention.
3 is a perspective view of a high-speed scanning apparatus 1 according to an embodiment of the present invention.
4 is a flowchart of a scanning method using the high-speed scanning apparatus 1 according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Unless defined otherwise, all terms (including technical and scientific terms) used herein may be used in a sense commonly understood by one of ordinary skill in the art to which this invention belongs. Also, commonly used predefined terms are not ideally or excessively interpreted unless explicitly defined otherwise.

The terminology used herein is for the purpose of illustrating embodiments and is not intended to be limiting of the present invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. The terms " comprises "and / or" comprising "used in the specification do not exclude the presence or addition of one or more other elements in addition to the stated element.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a scanning method using a high-speed scanning apparatus 1 according to an embodiment of the present invention.

As shown in Fig. 1, in order to perform a scanning method using the high-speed scanning device 1, the present invention comprises a light scanner 11 for scanning a target object 2 by irradiating a laser beam onto the target object 2, A vision sensor 12 for capturing an image and extracting the object 2 from the image, and a pedestal 13 for supporting the optical scanner 11 and the vision sensor 12. [ Here, the optical scanner 11 refers to an apparatus that scans an object using light, and includes a laser (LIDAR) using a laser. The object 2 is an object to acquire distance information using the vision sensor 12 and the light scanner 11, and includes not only one but also a plurality of objects.

The vision sensor 12 rotates 360 degrees around itself and can take an image of the surroundings. If the user sets only a certain direction, the vision sensor 12 can also photograph the image only in the corresponding direction. The vision sensor 12 includes an image acquisition unit 121 for capturing an image of the corresponding region and an image processing unit 122 for extracting the object 2 by processing the acquired image, An operation unit 123 for calculating the coordinates of the light source 2 and calculating the angle to be scanned by the light scanner 11 based on the coordinates, and a communication unit 124 for transmitting the angle value and the control signal.

The image acquiring unit 121 acquires a two-dimensional image by photographing a corresponding area using an image sensor and is capable of photographing a subject such as a general CMOS (Complementary Metal Oxide Semiconductor) device or a CCD (Charge-Coupled Device) A camera element can be used. Here, the corresponding region refers to a space in which the object 2 exists, and is generally a three-dimensional space.

The image processing unit 122 first extracts edge information on image pixels from the acquired image. A gradient formula generally used for extracting the edge information can be used. The contour of the object 2 is revealed through the extracted edge information, and the scan area to be scanned by the light scanner 11 is determined based on the outline. Preferably, the vision sensor 12 may further include a storage unit (not shown) for storing the acquired image or various data. In this case, data on outline information is stored in advance in the storage unit (not shown), and the congestion of the object 2 can be recognized and discriminated by matching with the obtained outline information. As a method of extracting feature points for image matching, Scale Invariant Feature Transform (SIFT) or SURF (Speed Up Robust Features) techniques can be used. However, since the present invention aims at obtaining information quickly by shortening the time, .

The calculating unit 123 calculates an angle value for rotating the optical scanner 11 to scan the determined scan area. Since the rotation of the optical scanner 11 pans and tilts with respect to the x and y axes, the angular value requires at least two angles of the fan and an angle of the tilt. The angle value calculation is performed based on the position coordinates of the determined scan area and the lengths of the horizontal and vertical lengths of the area. As will be described below, the optical scanner 11 and the vision sensor 12 are fixedly coupled to each other so as to be constrained to operate. In this case, since the optical scanner 11 and the vision sensor 12 rotate together, the optical scanner 11 faces the same direction as the vision sensor 12 when the vision sensor 12 photographs the corresponding region. Accordingly, when the vision sensor 12 finishes imaging of the corresponding region, the optical scanner 11 can perform scanning immediately without rotating toward the corresponding region, thereby further shortening the scanning time. In this case, when calculating the angle value by the operation unit 123, the reference of the initial value becomes the central part of the image photographed by the vision sensor 12.

The communication unit 124 transmits a command signal and the angle value to the pedestal 13 so that the pedestal 13 makes a rotation corresponding to the angle value and sends the command signal and the angle value to the light scanner 11 so that the light scanner 11 starts scanning And transmits a command signal.

The pedestal 13 supports the optical scanner 11 and the vision sensor 12 and includes the motor 131 so that the optical scanner 11 and the vision sensor 12 function in various directions . The pedestal 13 may be coupled to the light scanner 11 or the vision sensor 12 while being fixed to the floor, but it is not limited thereto and may have various types of engagement.

2 is a reference view showing the basic principle of RIDAR (LIDAR) in the optical scanner 11 according to an embodiment of the present invention.

The configuration of the LIDAR is variously configured according to fields, but the basic configuration is as shown in FIG. 2, the laser transmitter 111 for generating a laser and transmitting the laser to an area to be scanned, A controller 113 for transmitting and receiving signals and data, a lens 114 for refracting the laser beam transmitted and received by the laser transmitter 111 and the laser detector 112 to adjust the traveling direction of the laser beam, ).

Rida can be classified into a time-of-flight (TOF) method and a phase-shift method according to a modulation method of a laser signal. As shown in FIG. 2, the TOF method measures the time that the laser transmitting unit 111 emits laser pulse signals and the reflected pulse signals from the objects 2 within the measurement range arrive at the laser detecting unit 112 It is a way to calculate distance. The phase-shift method is a method of calculating a time and a distance by emitting a continuously modulated laser beam with a specific frequency and measuring a phase change amount of a signal reflected from the object 2 within the measurement range.

A laser light source may have a specific wavelength or a variable wavelength in a wavelength range of 250 nm to 11 m, and recently, a semiconductor laser diode characterized by small size and low power is widely used. Since the wavelength of the laser has a direct influence on the permeability to the air, cloud, rain, and eye protection, the choice of wavelength is important depending on the field of use. In determining the performance of the optical scanner 11, basically, not only the laser output, the wavelength, the spectral characteristics, the pulse width and the shape but also the receiver sensitivity and dynamic range of the receiver and the characteristics of the optical filter and the lens 114, to be. In addition to this, Field Of View (FOV) indicating the measurement angle of the receiver, Field Stop for selecting the measurement range, and FOV overlap characteristic of the laser beam and the receiver are also important factors.

The existing Lada technology has been mainly studied for the purpose of meteorological observation and distance measurement. Recently, technologies for meteorological observations in satellite, unmanned robot sensor and 3D image modeling have been studied.

3 is a perspective view of a high-speed scanning apparatus 1 according to an embodiment of the present invention.

As shown in Fig. 3, the vision sensor 12 and the light scanner 11 are coupled side by side. According to an embodiment of the present invention, the vision sensor 12 and the image sensor 12 can be supported by a single pedestal 13 while having a more compact structure. The optical scanner 11 is positioned vertically and coupled. Either the vision sensor 12 or the light scanner 11 may be located above or below the light sensor 11, but according to an embodiment of the present invention, the light scanner 11 is located below the vision sensor 12 and is coupled , And the pedestal (13) is coupled to the optical scanner (11) to rotate the optical scanner (11).

The smaller the distance d1 between the center of the lens of the vision sensor 12 and the center of the lens of the laser transmission unit 111, the smaller the error in the calculation of the angle value. Therefore, the vision sensor 12 and the light scanner 11 are combined so that the lens of the vision sensor 12 and the lens of the laser transmitter 111 are close to each other. 3, the two axes connecting the focus of the lens of the vision sensor 12 and the focus of the lens of the laser transmission unit 111 are in parallel with each other, and the vision sensor 12 and the optical scanner 11, Are directed in the same direction.

As described above, the optical scanner 11 and the vision sensor 12 are fixed and coupled to each other while being constrained to each other, and the optical scanner 11 and the vision sensor 12 may be integrally formed.

In this case, since the optical scanner 11 and the vision sensor 12 rotate together, when the vision sensor 12 rotates to photograph the corresponding region, the optical scanner 11 rotates together with the vision sensor 12, (12). Accordingly, when the vision sensor 12 finishes imaging of the corresponding area, the optical scanner 11 can perform scanning immediately without rotating toward the corresponding area, thereby further shortening the scanning time. In this case, the reference at the time of calculating the angle in the operation unit 123 is the central part of the image captured by the vision sensor 12. [ It is assumed that the distance d1 during the calculation of the angle value is very small as compared with the distance d2 from the lens of the laser transmitting unit 111 to the object 2. [ The fact that the optical scanner 11 and the vision sensor 12 are fixed and coupled means that not only the optical scanner 11 and the vision sensor 12 are easily separated from each other but also the optical scanner 11 and the vision sensor 12 ) Do not rotate or move independently of each other.

The high-speed scanning apparatus 1 according to an embodiment of the present invention includes a pedestal 13 for supporting the optical scanner 11 and the vision sensor 12 to function in various directions while being rotated. The optical scanner 11 and the vision sensor 12 must have at least two degrees of freedom in order to perform functions by rotating all directions. 3, the pedestal 13 is provided with at least two motors 131 so that the optical scanner 11 can pan and tilt around at least two axes, And are installed on the pedestal 13 so as to be orthogonal to each other.

3, the pedestal 13 is fixed to the floor, and connection portions formed on both side surfaces of the light scanner 11 and both side surfaces of the pedestal 13 are mutually connected to each other so that the light scanner 11 is supported on the pedestal 13 so as to be rotatable. This pivoting motion includes a yaw-directional rotation indicating the relative rotational movement between the upper and lower portions of the pedestal 13 and a pitch-directional rotation indicating the relative rotational movement of the light scanner 11 with respect to the connecting portion of the pedestal 13. [

4 is a flowchart of a scanning method using the high-speed scanning apparatus 1 according to an embodiment of the present invention.

The vision sensor 12 first photographs the corresponding area (S401). As described above, the vision sensor 12 rotates 360 degrees around itself and can take an image of the surroundings. However, when the user sets only a certain direction, the vision sensor 12 can also take an image only in the corresponding direction. If the image acquisition unit 121 acquires the image of the corresponding region (S402), the image processing unit 122 determines whether the object 2 exists in the image (S403). If no edge information is extracted from the image, the object 2 does not exist. In this case, the light scanner 11 does not perform scanning, and the vision sensor 12 photographs another region and repeats the above steps .

However, if the edge information is extracted from the image, the target object 2 exists in the image processing unit 122, and the target object 2 is extracted (S404). The calculation unit 123 sets the position of the extracted object 2 as a scan area and the calculation unit 123 calculates the angle of rotation of the light scanner 11 based on the position coordinates of the object 2, (S405). At this time, since the vision sensor 12 and the optical scanner 11 are fixedly coupled to each other, the initial value in calculating the angle value is determined based on the center of the image. The pedestal 13 receives the angle value through the communication unit 124 and rotates in accordance with the angle value. The optical scanner 11 performs scanning toward the object 2 (S406). Thus, the distance information of the object 2 is obtained (S407). If there are a plurality of target objects 2, steps S404, S405, S406, and S407 are repeated by setting the order for each target object 2. At this time, the initial value in calculating the angle value is determined based on the scan area of the previous object 2.

The optical scanner 11 can quickly perform the scanning operation and the vision sensor 12 and the optical scanner 11 The optical scanner 11 can start scanning immediately after the image sensing of the vision sensor 12 is performed so that scanning can be performed more quickly and the distance information of the object 2 can be obtained quickly.

It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

1: High-speed scanning device 2: Target object
11: light scanner 12: vision sensor
13: pedestal 111: laser transmitter
112: laser detection unit 113:
114: Lidar lens 121: Image acquisition unit
122: image processor 123:
124: communication unit 131: motor

Claims (6)

Acquiring an image of a specific region using a vision sensor;
Extracting an object from the acquired image and setting a scan area;
Calculating a rotation angle for performing scanning only within the scan area;
Rotating the optical scanner that performs the scanning according to the calculated rotation angle; And
And acquiring distance information of the object by the optical scanner. The method according to claim 1,
Wherein the vision sensor and the optical scanner include:
And is rotatably supported by a pedestal so as to be free from relative movement. 3. The method of claim 2,
Wherein an axis connecting the center of the lens included in the vision sensor and an axis connecting the focal point and the center of the lens of the laser transmitter included in the optical scanner are parallel to each other, Scanning direction using a high-speed scanning device. 3. The method of claim 2,
The pedestal,
A scanning method using a high-speed scanning device comprising at least two motors, wherein the vision sensor and the optical scanner are rotatable in a yaw direction and a pitch direction. 5. The method of claim 4,
Wherein the at least two motors comprise:
And the motor shaft is installed on the pedestal so that the motor shaft is orthogonal to each other so that the pedestal can rotate in the yaw direction and the pitch direction. 3. The method of claim 2,
The rotation angle
Wherein the calculation is performed on the basis of the position information of the object and the length of the object in the scan area.

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