JP3430001B2 - Vehicle position measuring device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle position measuring device for measuring a running position of a vehicle with high accuracy. [0002] In recent years, GPS (Global Posi)
Tying System (Global Positioning System)
Vehicle position measuring devices based on kinematic positioning using only a vehicle are rapidly spreading, and are also used for applications such as checking a route to a destination. A vehicle speed detecting device which outputs a vehicle speed pulse signal based on rotation of an axle of the vehicle and detects the signal to measure a moving distance of the vehicle in a traveling direction is installed in general vehicles and widely used. I have. This vehicle speed detecting device is installed in a transformer box of a vehicle, and is operated directly by an internal gear. The travel distance in the traveling direction of the vehicle is calculated by integrating the vehicle speed pulse signal for a predetermined time. [0004] A vehicle position detection system is disclosed in, for example, Japanese Patent Application Laid-Open No. 9-61524. This is to detect the relative position of another vehicle with respect to the own vehicle by triangulation using an infrared sensor. [0005] Since the conventional vehicle position measuring device is configured as described above, a vehicle position measuring device using only GPS is surrounded by a tunnel or a group of buildings. In such places, communication with communication satellites was not possible, and there was a problem that positioning could not be performed. [0006] A GPS having an accuracy of cm used for measurement and the like.
Then, if communication with a communication satellite is interrupted even for a moment, such as when a vehicle passes under a radio wave obstacle such as an overpass, to measure position again with high accuracy, measure the error at the GPS reference station and then move Correction must be performed from the position measurement by GPS measured on the body vehicle side, and measurement with an accuracy of several cm can be performed only one or two minutes after communication is restored, and quick measurement can be performed. There were issues such as inability to do so. Further, in the running distance measurement using only the vehicle speed detecting device, errors are accumulated in long-distance running due to changes in tire pressure, changes in wheel radius due to tire wear, changes in road surface friction, etc., and accuracy is maintained. There were issues such as inability to do so. The vehicle position detecting system disclosed in Japanese Patent Application Laid-Open No. 9-61524 detects the relative position of another vehicle with respect to the own vehicle. There was a problem that the absolute position could not be measured with high accuracy. SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and enables a vehicle position to be detected with high accuracy (a few centimeters of error) even in a tunnel or a place surrounded by buildings where GPS positioning is not possible. It is an object of the present invention to obtain a vehicle position measuring device that can be measured. In a vehicle position measuring device according to the present invention, a lateral distance measuring device emits electromagnetic waves toward a road side.
Transmitter for transmitting and reception for detecting the reflected wave from the roadside
The lateral ranging sensor consisting of the
Processing unit is provided in the rear and rear sections,
Each distance detected by each lateral distance sensor
To calculate the position of the vehicle . An embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a block diagram showing a vehicle position measuring device according to Embodiment 1 of the present invention, FIG. 2 is a block diagram showing an internal configuration of a lateral distance measuring device, and FIG. 3 is a measuring method using a lateral distance measuring device and a vehicle speed detecting device. FIG. 4 is a plan view showing a measuring method using a lateral distance measuring apparatus. In the figure, 1 is a vehicle, 2 is a kinematic positioning device (GPS positioning device) which is a mobile station that performs highly accurate kinematic positioning by GPS, and 3 is a vehicle-mounted GPS.
Antenna (GPS positioning device), 4 is a vehicle-mounted wireless device, 5 is a vehicle-mounted wireless antenna, 6 is a terrestrial wireless device, 7 is a kinematic positioning device (GPS positioning device) as a reference station, 8 is a reference station GPS antenna (GPS positioning device), 9 is a roadside communication device (LCX). Reference numeral 10 denotes a vehicle speed detecting device for measuring the distance traveled by the vehicle 1 due to the rotation of the axle 11 or the tire.
For example, a vehicle speed pulse transmitter (not shown) that transmits four pulses per rotation of the axle 11 is provided. The vehicle speed detecting device 10 uses a speedometer and a mileage integrating device installed in a general vehicle, and is installed in a vehicle power unit 12 such as a transformer box. Reference numeral 13 denotes a roadside such as a guardrail, and reference numeral 14 denotes a sign marker provided as a high-luminance reflector provided on the roadside 13. Reference numeral 15 denotes a lateral distance measuring device that measures the distance between the vehicle 1 and the roadside 13 and detects that the vehicle 1 has passed the sign marker 14. The lateral distance measuring device 15 includes a lateral distance measuring sensor 16 and a lateral distance measuring unit 17. The lateral distance measuring sensor 16 includes a light transmitting unit (transmitting unit) 16a that transmits a plurality of near-infrared rays (electromagnetic waves) to the roadside 13;
And a light receiving section (receiving section) 16b for receiving the reflected light from the vehicle 1. A total of four light receiving sections are installed on the front, rear, left and right sides of the vehicle 1. That is, distance measurement data from both road sides 13, 13 of the road can be calculated. Further, the lateral distance measurement processing unit 17 analyzes the reflected light received by the light receiving unit 16b, calculates a distance between the vehicle 1 and the roadside 13 by calculating a delay time by comparing the reflected light with other significant signals, It is configured to calculate the luminance of the reflected light and determine whether the vehicle 1 has passed in front of the sign marker 14.
As described above, the lateral distance measuring device 15 is configured to be capable of measuring a distance by a so-called spread spectrum method. Reference numeral 18 denotes the vehicle 1 based on the most accurate measured value among the measured values of the kinematic positioning device 2, the measured values of the vehicle speed detecting device 10, and the measured values of the lateral distance measuring device 15.
Is a processing device that calculates the position of the vehicle and communicates with the terrestrial wireless device 6 using the on-vehicle wireless device 4. The processing device 18 is provided with software for determining the significance / insignificance of each of the measured values and calculating the position of the vehicle 1, and also pre-registers the installation position information (latitude / longitude) of the sign marker 14 and the like. Have been. Next, the operation will be described. First, the outline of the operation of the entire system will be described, and then the individual operation of each device will be described in detail. Usually, position measurement is performed using information from the kinematic positioning device 2 with the highest accuracy. The kinematic positioning device 2 uses a kinematic positioning device 7 as a reference station in order to obtain an accuracy of several cm.
Error information of the measured position is received, and the measured position is corrected to obtain a final absolute position. This value is converted by the processing device 18 into a value indicating a position on the road. On the other hand, if the processing unit 18 determines that signals from the required number of communication satellites cannot be captured due to obstacles such as traveling in a tunnel or a building, the vehicle speed detection unit 10 will be described later. Measurements and lateral ranging 15
Is used to calculate the position of the vehicle 1. The lateral distance measuring device 15 outputs a measured value from the roadside 13 and a sign marker recognition signal when the sign marker 14 is detected. Since the vehicle 1 normally travels in the left lane of the road, distances L1 and L2 between the vehicle 1 and the left roadside 13 are provided before and after the left side of the vehicle 1 as shown in FIG. Lateral ranging sensors 16, 16
And the deviation angle θ from the roadside 13 is determined from the measured distances L1 and L2 before and after. In the processing device 18, the vehicle speed detecting device 1
The moving distance L3 in the vehicle traveling direction is obtained by integrating the vehicle speed pulse signal output from 0. The deviation angle θ from the roadside 13 and the moving distance L in the vehicle traveling direction
Then, the position of the vehicle 1 in the traveling direction is obtained from the number 3. However, the vehicle speed pulse signal in this case includes an error due to a change in tire pressure, a change in wheel radius due to tire wear, a change in road surface friction, and the like. Therefore, in order to eliminate this error, the sign marker function of the lateral distance measuring device 15 is used. That is, the lateral distance measuring device 15
Each time the signature marker 14 is detected and the signature marker recognition signal is input to the processing device 18, the processing device 1
8, the position of the vehicle 1 is calculated again using the position information (longitude / latitude) of the sign marker 14 registered in advance. As a result, while the vehicle 1 is traveling between the sign markers 14, the above error is included. However, the vehicle position is recalculated when the vehicle 1 passes in front of the sign marker 14. Be eliminated. Therefore, even when positioning by the kinematic positioning device 2 is unstable due to obstacles such as traveling in a tunnel or a building, high-precision positioning can be performed. Next, the operation of the vehicle speed detecting device 10 will be described in detail. As shown in FIG. 3, a vehicle speed pulse signal is output from the vehicle speed detection device 10 by the rotation of the axle 11 to the processing device 1.
8 is output. In the processing device 18, the pulse signals are integrated, and a moving distance L3 in the traveling direction of the vehicle 1 is obtained. Since the vehicle speed detection device 10 uses a speedometer and a mileage integration device installed in a general vehicle, if the number of output of the vehicle speed pulse signal per one rotation of the axle 11 is increased, the speed per one pulse is increased. The traveling distance is shortened, and the measurement accuracy is improved. However, in the present invention, the accuracy is easily improved by improving the calculation algorithm without increasing the number of output vehicle speed pulse signals. That is, in the conventional calculation algorithm, regardless of whether or not the vehicle speed pulse signal is input, the error is accumulated because the signal continues to be counted until the vehicle speed pulse signal is read out after a certain period of time. On the other hand, according to the calculation algorithm of the present invention, when the processing device 18 receives the vehicle speed pulse signal from the vehicle speed detection device 10, the processing distance L3 in the traveling direction of the vehicle is controlled by an interrupt process on software.
And the distances L1 and L2 from the roadside 13 are calculated. This increases the load on the processing device 18,
Dramatic improvement in accuracy can be expected compared to the conventional method.
Note that the processing device 18 retains the previous value until the vehicle speed pulse signal is received and thus differs from the actual value. However, the error is within several cm immediately after the vehicle speed pulse signal is generated. Next, the operation of the lateral distance measuring device 15 will be described in detail. In order to measure the distance, the lateral distance measuring sensor 16 of the lateral distance measuring device 15 constantly transmits a plurality of pulses of near infrared rays from the light transmitting unit 16a, and receives the reflected light from the roadside 13 by the light receiving unit 16b. Then, the lateral ranging processing unit 17 calculates the distances L1 and L2 between the vehicle 1 and the roadside 13 based on the delay time of the received light signal.
In this case, the vehicle 1 is provided with a total of four lateral distance measuring sensors 16 for front, rear, left and right.
Distance data from 3 and 13 are obtained. However, due to the characteristics of the lateral distance measuring device 15, the error increases as the distance from the measurement target increases, so the vehicle position is calculated based on the value of the data closer to the roadside 13.
That is, since the vehicle 1 normally travels in the left lane of the road, the distance between the vehicle 1 and the road 13 is not the right side but the left side.
The separation data L1 and L2 are used for calculating the vehicle position. Before that
-Recognize in advance the difference in distance at the rear (L1-L2)
From the lateral ranging sensor 16 in front of the vehicle
From the distance to the later lateral distance sensor 16, the roadside
13 is calculated. The distance measurement in the spread spectrum method is usually performed by PN
Since the correlation between codes is used, it is not possible to obtain a distance accuracy within one pulse. When using light as a medium,
Even in order to obtain the accuracy of several tens of cm, the chip rate of the PN code becomes 300 MHz or more, and it is very difficult to modulate the laser radar diode and the light emitting diode. Realization is nearly impossible. Therefore, in the present invention, a distance measurement is performed using the gradient of the auto-correlation between the transmission PN code and the reception PN code, thereby achieving a measurement accuracy of several cm. The lateral distance measuring device 15 also has a function of detecting the sign marker 14. That is, when the vehicle 1 passes in front of the sign marker 14, the sign marker 14
The amount of reflected light from the roadside 13 is larger than that at a place where is not installed. The increase in the amount of reflected light is recognized by the lateral distance measuring device 15 and the sign marker recognition signal is processed by the processing device 18.
Output to Since the installation position information (latitude / longitude) of the sign marker 14 is registered in the processing device 18 in advance, each time the signature marker recognition signal is input to the processing device 18, the lateral distance measurement is performed. Roadside 1 by device 15
Then, the position of the vehicle in the traveling direction is corrected and calculated using the distance information from the vehicle 3 and the distance information obtained by integrating the pulse signal from the vehicle speed detection device 10. By this correction calculation, the position error in the vehicle traveling direction accumulated by the integration of the pulse signal from the vehicle speed detection device is eliminated, and highly accurate positioning can be obtained. Vehicle location (latitude
Longitude) indicates the position of the vehicle 1 with respect to the sign marker 14.
It is calculated using this. Car from sign marker 14
The distance in the road traveling direction to both cars 1 is
Difference between the moving distance L3 by the pulse signal integration and the roadside 13
From the angle θ. Also, from the roadside 13 to the vehicle 1
The distance in the cross direction at the road is measured from the lateral ranging device.
Obtained from the fixed distance L1 and the deviation angle θ between the roadside 13
You. Therefore, the road from the sign marker 14 to the vehicle 1
The distance in the direction of travel and the distance in the direction crossing the road can be calculated.
The installation position information (latitude / longitude) of the sign marker 14 is
Because it is known, the vehicle position (latitude / longitude) can be calculated
Wear. As described above, according to the first embodiment, the vehicle position can be measured with a high accuracy of several centimeters even in a place surrounded by a group of tunnels or buildings where the position cannot be detected by the GPS. Is obtained. Also, there is no need for advanced sensors etc. on the infrastructure side equipment,
It is only necessary to install the sign marker 14 on the roadside 13, and even in the case of disseminating it on a general road, the effect that the facility cost is small can be obtained. Further, the distance measuring means by the lateral distance measuring device 15 using the spread spectrum method has features such as good noise resistance, low transmission power, strong resistance to interference, and no interference with existing communication methods. This is very effective when used in a society where the radio communication infrastructure has been developed in recent years. In addition, since the measurement accuracy is improved by improving the calculation algorithm using the vehicle speed detection device 10 installed in a general vehicle, the manufacturing cost can be reduced and the device can be easily spread. Is also obtained. In the first embodiment, the description has been made on the assumption that near-infrared rays are used as electromagnetic waves transmitted from the light transmitting section 16a. However, the present invention is not limited to this, and visible rays, microwaves, and millimeter waves may be used. . As described above, according to the present invention, the latte
A transmission unit that transmits electromagnetic waves toward the roadside
And a receiver that detects the reflected wave from the roadside.
Ral distance sensors on the front and rear sides of both sides of the vehicle
The processing device is provided for each lateral measurement of the lateral distance measuring device.
Using each distance detected by the distance sensor,
Since the position is calculated , the position of the vehicle can be measured accurately.
There is an effect that can be performed well . [0031]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a vehicle position measuring device according to a first embodiment of the present invention. FIG. 2 is a block diagram showing an internal configuration of the lateral distance measuring device. FIG. 3 is a block diagram showing a measuring method using a lateral distance measuring device and a vehicle speed detecting device. FIG. 4 is a plan view showing a measuring method using a lateral distance measuring device. [Description of Signs] 1 vehicle, 2,7 kinematic positioning device (GPS positioning device), 3 in-vehicle GPS antenna (GPS positioning device), 8 reference station GPS antenna (GPS positioning device),
10 vehicle speed detection device, 11 axle, 13 roadside, 14
Sign marker, 15 lateral distance measuring device, 16 lateral distance measuring sensor, 16a light transmitting unit (transmitting unit), 16b light receiving unit (receiving unit), 17 lateral distance processing unit, 18 processing unit, L1, L2 distance to roadside , L3 travel distance (travel distance in the traveling direction of the vehicle).

Continuation of front page (56) References JP-A-2-124420 (JP, A) Masahiro Takeda, Yukiko Hanada, Ryuji Kohno, Study on Inter-Vehicle Communication and Ranging with Spread Spectrum using Interference Cancellation Circuit, Electronic Information IEICE Technical Report, Japan, The Institute of Electronics, Information and Communication Engineers, March 19, 1997, 25-30 (58) Fields investigated (Int. Cl. ⁷ , DB name) G01C 21/00

Claims (1)

(57) [Claims 1] G that measures the position of a vehicle by GPS
A PS positioning device, a vehicle speed detection device that measures a moving distance in a traveling direction of the vehicle based on rotation of an axle of the vehicle,
A lateral distance measuring device for measuring the distance between the vehicle and the roadside on the basis of the delay time of the reflected wave from the transmitted the roadside electromagnetic waves toward the road, at least one or more significant of said each measurement processing apparatus and the vehicle position measuring apparatus odor having a for calculating the position of the vehicle based on the Do measurements
The lateral ranging device transmits an electromagnetic wave toward the roadside.
Transmitting unit and a receiving unit that detects the reflected wave from the roadside
The lateral ranging sensor consisting of
The processing device is provided in each of the lateral and rear portions,
Using each distance detected by the distance sensor,
A vehicle position measuring device for calculating a position.