JP2010002225A - Apparatus, system and method for measuring position by utilizing visible light communication - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a position measuring apparatus easily making a position measuring system practicable which utilizes a visible light communication and an image processing. <P>SOLUTION: In the position measuring system utilizing the visible light communication and the image processing, a vehicle is loaded with image sensors 19A, 19B and the in-vehicle position measuring apparatus 10. The image sensors 19A, 19B double as an receiving section of a visible light-communication beacon and an image inputting section for performing the image processing in order to measure a distance from a position of the visible light-communication beacon. The in-vehicle position measuring apparatus 10 measures the position of the traveling vehicle, based on inputs from the image sensors 19A, 19B. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a position measurement device using visible light communication, and more particularly to a position measurement device that measures the position of a vehicle traveling on a road.

  In recent years, as a method for measuring the current position of a vehicle typified by an automobile, a position measurement (position measurement) method using a GPS (global positioning system) has been incorporated into a car navigation device, for example.

In recent years, a position measurement method using a visible light communication system has been proposed as a method for realizing a highly accurate position measurement function. The visible light communication system is a communication method using a visible light signal, and transmits a visible light signal modulated with position information necessary for a position measurement function (see, for example, Patent Document 1).
JP 2007-81703 A

  The vehicle position measurement technique using GPS is a technique for measuring a position using radio waves transmitted from a plurality of satellites. However, in general, the measurement accuracy of vehicle position measurement using GPS has a position error of several tens to hundreds of meters, and in order to correct this, processing for matching with a map or the like is required. Furthermore, even if such correction processing is executed, it is difficult to eliminate a position error of several meters.

  On the other hand, in addition to GPS, it is possible to realize a position measurement method that can measure the current position of a vehicle traveling on a road with high accuracy by combining visible light communication technology and image processing technology. Specifically, a method of measuring the position of a vehicle equipped with the in-vehicle device by using the in-vehicle device including two CCD cameras for image input and a receiving element for receiving visible light It is. However, such a position measuring apparatus requires equipment and parts such as two CCD cameras and a photodiode as a receiving element, and therefore requires a relatively high cost to be realized as a product. For this reason, it is difficult to put into practical use a position measurement system that combines visible light communication technology and image processing technology.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a position measuring device that can easily put a position measuring system using visible light communication and image processing into practical use.

  An aspect of the present invention relates to a position measurement system that combines a visible light communication beacon that transmits position information with a visible light signal and an image process for measuring a distance from the position of the visible light communication beacon. It is a position measurement device having an image input means that also functions as an optical communication beacon receiving function.

  A position measuring device according to an aspect of the present invention is a position measuring device provided in a vehicle traveling on a road, wherein the image input means inputs images of a plurality of illumination lamps arranged along the road, and the image input means Means for receiving visible light emitted from each of the illuminating lamps, obtaining position information in a visible light communication signal included in the visible light, and each of the illuminating lights input by the image input means. Based on the image, distance calculation means for calculating the distance between the vehicle and each of the illuminating lights, and selecting the illuminating lamp with the shortest distance from the vehicle based on the distance by the distance calculating means, It is the structure provided with the position measurement means which measures the position of the said vehicle using the positional information contained in the used visible light communication signal, and the distance of the said vehicle and the said selected illumination light.

  According to the present invention, a position measurement system using visible light communication and image processing can be easily put into practical use, particularly by realizing a position measurement device mounted on a vehicle at low cost.

  Embodiments of the present invention will be described below with reference to the drawings.

(System configuration)
FIG. 1 is a diagram illustrating a main part of the position measurement system according to the present embodiment.

  The present embodiment is a system that measures the current position of a vehicle 1 such as an automobile using a visible light communication system. This system is roughly divided into a road illumination pillar 3 provided at a fixed position in the vicinity of the road 2 on which the vehicle 1 travels, and a position measuring device mounted on the vehicle 1 (hereinafter referred to as an in-vehicle position measuring device). It consists of ten.

  The road illumination pillar 3 includes a road illumination lamp 30 for performing illumination on the road 2 and a visible light communication device 31. The road illumination lamp 30 has a light emitting diode element for illumination (hereinafter referred to as LED), emits illumination light 300 for illuminating the road 2, and functions as a visible light communication beacon described later.

  The visible light communication device 31 configures a visible light communication beacon that drives and controls the LED of the road illumination lamp 30 and transmits a visible light communication signal 310 including position information. Hereinafter, in this embodiment, the equipment comprised of the road illumination pillar 3, the road illumination lamp 30, and the visible light communication device 31 provided at a fixed position may be collectively referred to as a visible light communication beacon.

  The vehicle-mounted position measurement device 10 receives a visible light communication signal transmitted from a visible light communication beacon, and measures the current position using position information demodulated from the visible light communication signal. The position information includes coordinate position information (longitude and latitude) of the visible light communication beacon at a fixed position and height information from the road 2 to the road illumination lamp 30 (that is, information indicating the height H of the visible light communication beacon). including.

(Configuration of visible light communication device)
As shown in FIG. 2, the visible light communication device 31 includes a power source 33, an LED driving device 34, a communication control device 35, and a storage device 36. It is fixed to the pillar 3. The LED drive device 34 is a driver that drives the LED 32 that is a light emitting element of the road illumination lamp 30. The communication control device 35 controls the blinking of the LED 32 via the LED driving device 34, thereby transmitting a visible light communication signal 310 modulated based on the position information stored in the storage device 36. The position information is information including coordinate position information and height information of a visible light communication beacon at a fixed position.

  The position information of the visible light communication beacon is stored in the storage device 36 in advance, or transmitted by wireless communication or the like and stored in the storage device 36. The visible light communication device 31 modulates the visible light emitted by the LED 32 of the road illumination lamp 30, thereby transmitting a visible light communication signal (visible light communication beacon signal) 310 carrying position information. The visible light modulation method may be appropriately selected from various modulation methods such as blinking control and RGB modulation.

(Configuration of in-vehicle position measuring device)
As shown in FIG. 3, the vehicle 1 according to the present embodiment includes two image sensors 19 </ b> A and 19 </ b> B together with the in-vehicle position measuring device 10. Each of the image sensors 19A and 19B is configured by, for example, a CMOS sensor or a photodiode array, functions as a receiving element that receives a visible light communication signal (visible light communication beacon signal), and images of a plurality of road illumination lights 30. Functions as an image input device.

  The on-vehicle position measurement device 10 includes a data processing unit 11, an image processing unit 12, a visible light communication unit 13, and an orientation measurement unit 14. The data processing unit 11 performs arithmetic processing necessary for position measurement processing described later.

  The image processing unit 12 inputs images of a plurality of road illumination lights 30 captured by the two image sensors 19A and 19B, and processes the images to extract a plurality of road illumination lights 30. That is, the image processing unit 12 extracts the position on the image for each road illumination lamp 30 from the input images of the image sensors 19A and 19B by the stereo image processing function. The data processing unit 11 calculates the distance between each road illumination lamp 30 and the vehicle 1 by the triangulation method from the position information calculated by the image processing unit 12 and the distance between the image sensors 19A and 19B on the vehicle 1. .

  The image processing unit 12 processes input images of the image sensors 19A and 19B, generates image information for calculating the height information of the visible light communication beacon, and transfers the image information to the data processing unit 11. Here, the data processing unit 11 and the image processing unit 12 are configured by a microprocessor and software.

  The visible light communication unit 13 demodulates position information from the visible light communication signal (visible light communication beacon signal) received by the image sensors 19A and 19B, and transfers the demodulated position information to the data processing unit 11. Here, the image processing unit 12 converts the visible light communication signal received by the image sensors 19 </ b> A and 19 </ b> B into an electrical signal and transfers the electrical signal to the visible light communication unit 13. The data processing unit 11 stores the position information of each road illumination light 30 demodulated by the visible light communication unit 13, that is, each visible light communication beacon, in an internal memory. The direction measurement unit 14 measures the travel direction of the vehicle 1 and outputs the measurement result to the data processing unit 11.

(Operation of position measurement system)
Hereinafter, the position measurement operation of the system of this embodiment will be described with reference to FIGS.

  In the present embodiment, as shown in FIG. 5, the vehicle 1 traveling on the road has a plurality of road illumination lights 30 in the traveling direction by the two image sensors 19 </ b> A and 19 </ b> B connected to the in-vehicle position measuring device 10. Each image is input by imaging (step S1). Here, as shown in FIG. 4, the vehicle 1 uses the image sensors 19 </ b> A and 19 </ b> B to display visible light together with an image 100 obtained by imaging the road illumination light 30 for each road illumination light 30 having a different distance from the vehicle 1. As a communication beacon, the visible light communication signal 200 on which the position information of the road lighting 30 is placed is received. That is, as shown in FIG. 5, the vehicle 1 receives the visible light communication beacons 200 </ b> A to 200 </ b> C from the road illumination lights 30 having different distances while traveling. The data processing unit 11 stores each position information of each road illumination lamp 30 demodulated by the visible light communication unit 13, that is, each visible light communication beacon 200A to 200C, in the internal memory.

  As shown in FIG. 5, the image processing unit 12 performs stereo image processing on the input image 190 of each of the image sensors 19A and 19B, and extracts each position on the image for each road illumination lamp 30 (step S2). Next, the data processing unit 11 uses a triangulation method based on the position information calculated by the image processing unit 12 and the distance between the image sensors 19A and 19B on the vehicle 1 to determine between the road illumination lights 30 and the vehicle 1. The distance is calculated (step S3).

  After calculating the distance to each road lighting 30, the data processing unit 11 selects the road lighting 30 closest to the vehicle 1, that is, the visible light communication beacon 200A having the shortest distance as shown in FIG. (Step S4). The data processing unit 11 extracts the position information of the selected visible light communication beacon 200A having the shortest distance from the internal memory.

  Next, as shown in FIG. 4, the data processing unit 11 calculates the height H of the road illumination pillar 3 corresponding to the selected visible light communication beacon 200 </ b> A having the shortest distance. Here, the data processing unit 11 calculates image information generated from the image processing unit 12 based on the input images 100 of the image sensors 19A and 19B, that is, image information for calculating the height information of the visible light communication beacon. Is used to calculate the height H. Specifically, the data processing unit 11 calculates the height H of the road illumination pillar 3 based on the position of each image sensor 19A, 19B, the imaging angle, and the position (position information) of the road illumination lamp 30.

  As shown in FIG. 4, the data processing unit 11 determines the ground of the road illumination pillar 3 having the road illumination lamp 30 with the shortest distance from the calculated height H of the road illumination pillar 3 with the shortest distance and the distance closest to the vehicle 1. Correction calculation for calculating the distance Lx to the vicinity is executed. Then, the data processing unit 11 uses the traveling direction obtained from the direction measuring unit 14, the distance Lx between the road illumination pillar 3 and the vehicle, and the position information of the visible light communication beacon 200A having the shortest distance, to determine the current vehicle. The position (longitude, latitude) of 1 is calculated (step S5).

  As described above, according to the present embodiment, two image sensors can be used without using a high-cost in-vehicle apparatus including two CCD cameras for image input and a receiving element for receiving visible light. And the position measuring system which combined visible light communication technology and image processing technology is realizable at low cost by the structure which uses the vehicle-mounted position measuring apparatus 10. FIG. Therefore, a position measurement system that can measure the position of a vehicle traveling on a road with high accuracy can be easily put into practical use by combining the visible light communication technique and the image processing technique.

  In the present embodiment, the configuration in which two image sensors are used as the image input device has been described. However, a monocular camera may be used. However, the processing procedure of the data processing unit 11 of the in-vehicle position measuring device 10 is different. In the present embodiment, the visible light communication beacon is configured using the road illumination lamp 30 provided at a fixed position on the road. However, the present invention is not limited to this, and is provided in a building or facility, for example. It may be constituted by a different illumination lamp. Further, the visible light communication beacon is not integrated with the illuminating lamp, but may be a dedicated facility (apparatus) that transmits a visible light signal.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

The figure which shows the principal part of the position measurement system regarding embodiment of this invention. The figure for demonstrating the structure of the visible light communication apparatus regarding this embodiment. The figure for demonstrating the structure of the vehicle-mounted position measuring apparatus regarding this embodiment. The figure for demonstrating the position measurement operation | movement of the system regarding this embodiment. The figure for demonstrating the image processing of the vehicle-mounted position measuring apparatus regarding this embodiment. The flowchart for demonstrating the process sequence of the system regarding this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Vehicle, 2 ... Road, 3 ... Road illumination pillar, 10 ... In-vehicle position measuring device,
DESCRIPTION OF SYMBOLS 11 ... Data processing part, 12 ... Image processing part, 13 ... Visible light communication part,
14 ... Direction measuring unit, 19A, 19B ... Image sensor, 30 ... Road light,
31 ... Visible light communication device, 32 ... Light emitting element (LED), 33 ... Power supply,
34 ... LED driving device, 35 ... communication control device, 36 ... storage device.

Claims (10)

In a position measuring device provided on a vehicle traveling on a road,
Image input means for inputting images of a plurality of illumination lamps arranged along the road;
Means for receiving visible light emitted from each of the illumination lamps using the image input means, and acquiring position information in a visible light communication signal included in the visible light;
Distance calculating means for calculating a distance between the vehicle and each illumination light based on an image of each illumination light input by the image input means;
Based on the distance by the distance calculation means, the illumination lamp of the shortest distance is selected from the vehicle, the positional information included in the visible light communication signal using the selected illumination lamp, and the vehicle and the selected illumination lamp A position measuring device comprising position measuring means for measuring the position of the vehicle using a distance. The image input means includes
The position measuring device according to claim 1, wherein the position measuring device includes a plurality of image sensors for imaging a plurality of illumination lamps and receiving the visible light. The distance calculating means includes
Means for performing stereo image processing on each image input by the plurality of image sensors and obtaining a position on the image of each illumination lamp;
The distance between each illumination light and a vehicle is calculated by a triangulation method using the position information for each illumination light and the distance between each image sensor. Position measuring device. The position measuring means includes
Means for calculating the height of the selected shortest distance lighting from the ground;
Means for correcting and calculating the distance to the shortest distance illuminating lamp using height information of the illuminating lamp,
The vehicle position is measured using the distance calculated by the correction calculation and the position information included in the visible light communication signal from the illumination lamp having the shortest distance. The position measuring device according to any one of 1 to 3. The position measuring means includes
Means for calculating the height of the selected shortest distance lighting from the ground;
Means for calculating and calculating a distance to the shortest distance illuminating lamp using the height information of the illuminating lamp;
Means for measuring the traveling direction of the vehicle,
The position of the vehicle is measured using the traveling direction, the distance calculated by the correction calculation, and position information included in a visible light signal from the illumination lamp having the shortest distance. The position measuring device according to any one of claims 1 to 3. A transmitting means for transmitting a visible light communication signal including position information using a plurality of illumination lamps arranged along a road on which the vehicle travels;
In a position measuring system including a position measuring device provided in the vehicle,
The position measuring device includes:
Image input means for inputting an image of each of the illumination lamps;
Means for receiving visible light emitted from each of the illumination lamps using the image input means, and acquiring position information in a visible light communication signal included in the visible light;
Distance calculating means for calculating a distance between the vehicle and each illumination light based on an image of each illumination light input by the image input means;
Based on the distance by the distance calculation means, the illumination lamp of the shortest distance is selected from the vehicle, the positional information included in the visible light communication signal using the selected illumination lamp, and the vehicle and the selected illumination lamp A position measuring system comprising position measuring means for measuring the position of the vehicle using a distance. The image input means includes
The position measurement system according to claim 6, wherein the position measurement system includes a plurality of image sensors for imaging a plurality of illumination lamps and receiving the visible light. The distance calculating means includes
Means for performing stereo image processing on each image input by the plurality of image sensors and obtaining a position on the image of each illumination lamp;
8. The distance between each illumination light and the vehicle is calculated by a triangulation method using position information for each illumination light and the distance between each image sensor. Position measurement system. The position measuring means includes
Means for calculating the height of the selected shortest distance lighting from the ground;
Means for correcting and calculating the distance to the shortest distance illuminating lamp using height information of the illuminating lamp,
The vehicle position is measured using the distance calculated by the correction calculation and the position information included in the visible light communication signal from the illumination lamp having the shortest distance. The position measurement system according to any one of 6 to 8. A position measuring method applied to a position measuring device provided in a vehicle traveling on a road,
A process of inputting images of multiple lighting lamps arranged along the road;
Receiving visible light emitted from each of the illumination lamps using the image input means, and obtaining position information of a visible light communication signal included in the visible light; and
A process of calculating the distance between the vehicle and each illumination light based on the image of each illumination light input by the image input means;
Based on the distance by the distance calculation means, the illumination lamp of the shortest distance is selected from the vehicle, the positional information included in the visible light communication signal using the selected illumination lamp, and the vehicle and the selected illumination lamp And a process for measuring the position of the vehicle using a distance.

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