KR101105144B1 - Positioning method of moving object - Google Patents

Abstract

The position of the movable body is accurately estimated by correcting the traveling distance and the traveling angle displacement of the movable body according to the horizontal axis inclination of the road which is the left and right slope and the longitudinal axis inclination of the road which is the inclination of the front and rear directions based on the traveling direction of the movable body.

The control unit receives the horizontal and horizontal inclinations of the left and right sides of the moving object and the longitudinal axis inclination in the front and rear directions, the traveling angle displacement amount of the moving object, and the traveling distance information signal from the sensor unit, and calculates the traveling distance per unit time of the moving object using the received traveling distance information signal. And correcting the driving angle displacement with the input horizontal axis inclination and the longitudinal axis inclination, and correcting the traveling distance per unit time with the input horizontal axis inclination and the longitudinal axis inclination, and using the corrected driving angle displacement and the driving distance per unit time. The position of the current time point is determined accurately from the position of the previous time point of the moving object.

Navigation, Dead Reckoning, GPS, Positioning, Reliability, Horizontal Axis. Longitudinal axis, slope

Description

Method for determining position of vehicle

1 is a block diagram showing the configuration of a navigation system to which the positioning method of the present invention is applied.

Figure 2 is a signal flow diagram showing the operation of the control unit according to the positioning method of the present invention.

3 is a view for explaining the principle of correcting the traveling angle displacement amount of the moving body according to the positioning method of the present invention when the moving object is traveling on the curved road of the horizontal axis inclination.

Figure 4 is a view for explaining the principle of correcting the travel distance of the moving body according to the positioning method of the present invention when the moving object is traveling on a straight road of the longitudinal axis.

Figures 5a to 5c is a view showing the position of the moving body determined according to the conventional positioning method and the positioning method of the present invention on a curved road of the horizontal axis inclination.

Explanation of symbols on the main parts of the drawings

100: GPS satellite 102: GPS receiver

104: command input unit 106: sensor unit

108: map data storage unit 110: control unit

112: display drive unit 114: display unit

The present invention relates to a positioning method of a moving object for estimating the position of the moving object by the detection signals of sensors installed in the moving object when the GPS (Global Positioning System) satellite transmits and the reliability of the position information signal received by the GPS receiver is low. The present invention relates to a positioning method of a moving body that accurately estimates the position of the moving body by correcting the traveling distance and the traveling direction of the moving body according to the horizontal axis inclination, which is a left and right inclination of the moving body, and the longitudinal axis inclination before and after the traveling direction detected by the two-axis inclinometer.

GPS is a global positioning system developed by the U.S. Department of Defense, which allows GPS receivers to receive location information signals transmitted by GPS satellites, and calculates the location of GPS receivers in three-dimensional coordinates using the received location information signals. will be.

The GPS locates a plurality of GPS satellites on a geostationary orbit above the earth and transmits location information signals, respectively, and the GPS receiver receives the location information signals transmitted by at least three GPS satellites among the plurality of GPS satellites. It calculates the position vector of the GPS receiver by detecting the distance between the GPS satellite and the GPS receiver and the position vector of the GPS satellite by using the received position information signal. Can be detected accurately with the coordinates of.

Using the GPS, highly accurate position coordinates can be obtained. However, as can be seen from the principle, GPS can be used only in an area that can accurately receive GPS location signals. In other words, the GPS that calculates the position of receiving the location information signal using the GPS satellites does not accurately receive the location information signal transmitted by the GPS satellite such as in a tunnel, in a wooded forest, or in an urban area surrounded by tall buildings. In the unreceivable area, the position coordinates for receiving the position information signal of the GPS satellites cannot be calculated or the calculation result of the position coordinates is very inaccurate.

Therefore, in the area where location calculation is impossible because GPS satellite location information signal is not received correctly, the dead reckoning system is introduced to estimate the current location of moving object by measuring moving distance and direction of movement. The dead reckoning system continuously measures the moving distance and the moving direction from the initial position of the moving object by using a odometer and a gyroscope each having a sensor for detecting the rotational speed of the driving wheel and the traveling angle displacement of the moving object, and the measurement By continuously integrating the rotational speed and the driving angle change amount of the drive wheel from one moving distance and the moving direction, the current position of the moving body is continuously estimated independently without external help. This dead reckoning system is known as dead-reckoning navigation system because it must know the position coordinates of the moving object.

However, the dead reckoning system should accurately set initial position information of the moving object, and also accumulate measurement errors of each sensor when the moving object travels for a long time while estimating the position of the moving object using the dead reckoning system. Due to this, there is a problem that the position of the moving object to be measured is incorrect. For example, in long tunnels or areas with high mountains obstructed on both sides of the road, the dead reckoning must continue to estimate the position of the moving object.However, due to its dead reckoning navigation, the accumulation of measurement errors has elapsed over time. There is a problem that increases in proportion to.

In order to overcome this problem, a mixed navigation system has been developed in which a gyroscope for detecting the displacement of a traveling angle of a moving object and a odometer for detecting a traveling distance of a moving object are combined with a GPS receiver. The mixed navigation system is also referred to as a GPS + dead reckoning system because the GPS receiver receives the position information signal and provides the initial position coordinates of the moving object required for dead reckoning navigation.

The mixed navigation system includes a gyroscope for detecting a traveling angle displacement of a moving object, position information of dead reckoning (dead reckoning) that can be obtained using a traveling odometer for detecting a traveling distance of the moving object, and a GPS receiver. The position of the moving object can be accurately estimated using the received position information signal.

The conventional dead reckoning in such a mixed navigation system determines the position of the moving object entirely depending on the traveling angle displacement detection signal of the gyroscope and the traveling distance detection signal of the odometer.

However, the driving angle displacement detection signal output from the gyroscope does not accurately reflect the three-dimensional inclination of the road, thereby causing an error in positioning of the moving object, and also the driving distance detection signal of the odometer. It did not reflect the front and rear inclination of the road on which the moving body traveled, and thus, there was a problem in that a lot of difference with the planar driving distance on the actual map occurred.

In order to reduce this error, there is a method of using a cumulative inclinometer, but since the measurement error accumulates continuously, the estimated position in the process of estimating the final position of the moving object is inaccurate over time. have.

An object of the present invention is to install a two-axis inclinometer of the movable body to detect the horizontal axis inclination in the left and right direction, the longitudinal axis inclination in the front and rear direction based on the traveling direction of the moving body, and the traveling distance and running of the moving object with the detected horizontal axis inclination and longitudinal axis inclination The present invention provides a method for determining the position of a movable body that can accurately estimate the position of the movable body by correcting the angular displacement.

According to the positioning method of the moving object of the present invention having the above object, when the reliability of the position information signal received by the GPS receiver is low, the dead reckoning is performed to estimate the position of the moving object using the detection signals of the gyroscope and the odometer. do.

The dead reckoning removes cumulative errors that may occur in the existing cumulative gyroscope by using horizontal axis inclinations on the left and right sides of the moving direction and vertical axis inclinations before and after the driving direction, and estimates the position of the moving body.

According to the present invention, the traveling distance of the moving object is corrected by performing a process of projecting the traveling distance detection signal of the traveling odometer of the moving object to the plane traveling distance on the digital map by using the detection signal of the horizontal axis inclination and the vertical axis inclination of the moving object.

In addition, the present invention corrects the direction angle information of the Z-axis gyroscope for estimating the traveling angle displacement amount of the moving body by using the signals of the horizontal axis gradient and the longitudinal axis gradient, and accurately estimates the position of the moving body.

Therefore, in the positioning method of the moving object of the present invention, the control unit receives from the sensor unit the horizontal axis inclination and the longitudinal axis inclination in the front and rear directions of the moving object, the traveling angle displacement amount of the moving object, and the traveling distance information signal, and travels. The distance information signal calculates the driving distance per unit time, corrects the traveling angle displacement amount by the input horizontal axis inclination and vertical axis inclination, and corrects the driving distance per unit time by the input horizontal axis inclination and vertical axis inclination, and corrects the correction. The current position is determined from the position of the previous point of time of the moving object by one traveling angle displacement amount and the traveling distance per unit time.

In addition, in the positioning method of the moving object of the present invention, the control unit receives the position information signal received by the GPS receiver to determine the reliability, and when the reliability is good, the position of the moving object is determined by the position information signal, the reliability is good In case of failure, the control unit receives from the sensor unit the horizontal axis inclination and the longitudinal axis inclination in the front and rear directions, the traveling angle displacement of the moving object, and the travel distance information signal, and the travel distance per unit time as the travel distance information signal. Compensate the traveling angle displacement amount by the received horizontal axis inclination and longitudinal axis inclination, and corrects the traveling distance per unit time with the received horizontal axis inclination and longitudinal axis inclination, and corrects the travel angle displacement amount and traveling per unit time. The current position is determined from the position of the previous viewpoint of the moving object by the distance. Characterized in that the location of the fuselage map matching on the digital map and display.

Hereinafter, with reference to the accompanying drawings will be described in detail the positioning method of the moving body of the present invention.

1 is a block diagram showing the configuration of a navigation system to which the moving object position detecting method of the present invention is applied. As shown therein, a GPS receiver 102 for receiving a location information signal transmitted by the GPS satellite 100, a command input unit 104 for inputting an operation command according to a user's operation, and a gyroscope and a odometer for a moving object. And a sensor unit 106 for installing a two-axis inclinometer for detecting the transverse and longitudinal axis inclinations of the moving object to detect the traveling angle displacement, travel distance, transverse inclination and longitudinal axis inclination of the moving object, and map data for storing digital map data. Using the storage unit 108 and the position information signal received by the GPS receiver 104 and the detection signal of the sensor unit 106 to determine the position of the moving object by mixed navigation, the horizontal axis tilt and vertical axis tilt Determine the location of the moving object by mapping the determined location of the moving object to digital map data stored in the map data storage unit 108, and then The controller 110 controls the display of the digital map data and the position of the moving object, and the display driver 112 displays the position of the digital map data and the moving object on the display unit 114 under the control of the control unit 110. .

In the navigation system configured as described above, the GPS receiver 102 receives the position information signal transmitted by the GPS satellite 100 when the user commands the driving guidance of the moving object through the command input unit 104 to the control unit 110. The sensor unit 106 generates a pulse signal corresponding to the displacement amount and the travel distance according to the moving of the moving object and is input to the control unit 110.                     

Then, the control unit 102 determines whether the reliability of the position information signal received by the GPS receiver 102 is good, and when the reliability of the position information signal is good, detects the current position of the moving object by the position information signal. After matching the detected current position with the digital map data stored in the map data storage unit 108, the output is displayed on the display unit 112 and displayed on the display unit 112.

In addition, when the position of the moving object cannot be accurately detected because the reliability of the position information signal received by the GPS receiver 102 is high, the control unit 110 has high reliability of the position information signal and thus, accurately detects the position of the moving object. From the final position, the sensor unit 106 accumulates the traveling angle displacement amount and the number of pulse signals according to the traveling distance, and detects the accumulated traveling angle displacement amount and the number of pulse signals and the number of pulse signals generated per unit time. The position of the moving object is estimated using the traveling speed of the moving object, and the estimated position of the moving object is corrected to the horizontal and vertical axis inclinations of the moving object detected by the two-axis inclinometer, and then the digital map data stored in the map data storage unit 108. Are mapped to the display, and output to the display driver 112 to be displayed on the display 114.

2 is a signal flow diagram showing the operation of the control unit according to the positioning method of the present invention. As shown in FIG. 200, the control unit 110 inputs the position information signal received by the GPS receiver 102 and the reliability of the position information signal determined by the reception sensitivity of the position information signal and the electric field strength. In step 202, it is determined whether the reliability of the position information signal is good.

If the reliability of the position information signal is good as a result of the determination in step 202, the controller 110 sets the longitude P _x and latitude P _y calculated from the position information signal in step 204.

When the reliability of the position information signal is not good as a result of the determination of step 202, the control unit 110 receives the detection signal of the sensor unit 106 in step 206 and in step 208 the sensor unit 106. ), The horizontal axis inclination θ _{x in} both the left and right directions of the moving object and the longitudinal axis inclination θ _{y in the front} and rear directions of the moving object are determined by the detection signal of the biaxial inclinometer.

In the next step 210, the traveling distance d per unit time of the moving body is calculated by the detection signal of the traveling speedometer of the sensor unit 106, and in step 212, the traveling angle of the moving body is detected by the detection signal of the gyroscope of the sensor unit 106. It is determined by the displacement amount Δθ.

In the next step 214, the moving distance of the moving object on the digital map is calculated and corrected by the horizontal axis inclination θ _x , the longitudinal axis inclination θ _y and the driving distance d per unit time as shown in Equation 1 below.

In the next step 216, the traveling angle displacement amount A _-1 of the previously detected moving object, the current traveling angle displacement amount Δθ of the detected moving object, and the horizontal axis inclination θ _x of the moving object are used as shown in Equation 2 below. The travel angle displacement A of the moving body is calculated.

When the traveling angle displacement A of the moving object at the present time is calculated, in step 218 the traveling angle displacement A is stored as the previous traveling angle displacement A ₋₁ , and in step 220, the hardness coordinates of the moving body are as follows. Calculate P _x and latitude coordinates P _y .

Longitude coordinates in step 204 or step 220, as described above, P _x, and when latitude coordinates P _y is calculated, the previous longitude coordinates, the longitude coordinates P _x and latitude coordinates P _y in step (222), P _x-1 and Substituting the previous latitude coordinate P _y-1 so that it can be used to determine the position of the next moving object, and in step 224 the values of the current position variables P _x and P _y to the map matching algorithm to provide the position of the moving object Map matching and display on digital maps.

In the next step 226, it is determined whether or not the moving object travels, and when the moving object travels, the process returns to step 200 to determine the longitude coordinate P _x and latitude coordinate P _y according to the reliability of the received position information signal. The operation is repeated, and the process ends when the moving object does not travel.

According to the present invention, when the moving body is traveling on the horizontal axis inclination curve road, the principle of correcting the displacement of the moving angle of the moving body using the horizontal axis and the longitudinal axis, and correcting the traveling distance of the moving body using the inclination on the straight road inclined to the vertical axis The principle of doing this is explained in more detail.

3 is a view for explaining the principle of the correction of the rotation angle in the positioning method of the present invention when the moving object rotates on the horizontal axis inclination curve road of the horizontal axis inclination is θ _x . As shown in FIG. 2, the two-axis inclinometer of the sensor unit 106 is installed on the moving body to detect the horizontal and vertical axis inclinations of the road on which the moving body travels. Δθ. The displacement change angle of the detected moving object can accurately determine the traveling angle displacement amount of the moving object on the digital map when Δθ is converted into an orientation change angle based on the vertical axis (Z axis).

이 되고, 그 이동체의 주행각도 변위량

에 상기 단계(216)에서 이전에 검출한 이동체의 주행각도 변위량 A_-1을 가산하여 현재 시점에서의 이동체의 주행각도 변위량 A를 보정한다.In FIG. 3, the azimuth change angle of the movable body is Δθ = ΔZ · cosθ, so that the displacement of the traveling angle of the movable body is

The displacement of the traveling angle of the moving object

The traveling angle displacement amount A- ₁ of the moving object detected previously in step 216 is added to correct the traveling angle displacement A of the moving object at the present time.

4 is a view for explaining the principle of correcting the travel distance in the positioning method of the present invention when the moving object is traveling on a straight road of the longitudinal axis inclination of the longitudinal axis is θ _y . As shown in the drawing, when the moving body travels on the inclined straight road, the driving distance D on the map is shorter than the actual driving distance d of the moving body.

Therefore, when the moving object travels on the inclined straight road, if the traveling distance of the moving object is not corrected on the digital map according to the inclination, an error proportional to the inclination of the road occurs and the position of the moving object cannot be accurately determined.

Therefore, in the present invention, when the moving body travels on the inclined straight road, the traveling distance D of the moving body is corrected by the following equation (4).

로 보정한다.In this case, when the horizontal axis inclination of the movable body is θ _y , the traveling distance D of the movable body is determined as in step 214.

Correct with

The present invention was applied to an inclined curved road as shown in FIG. 5A when the moving object traveled to determine the position of the moving object.

In the conventional method of determining the position of the moving body using only the detection signals of the gyroscope and the speedometer installed in the moving body, an error that determines that the moving body travels a position off the road as shown in FIG. 5B has occurred. However, in the present invention, the position of the moving body is determined by correcting the detection signals of the gyroscope and the speedometer to the horizontal and vertical axis inclinations, thereby accurately determining the position at which the mobile body normally drives the road as shown in FIG. 5C.                     

On the other hand, while the present invention has been shown and described with respect to specific preferred embodiments, various modifications and changes of the present invention without departing from the spirit or field of the invention provided by the claims below It can be easily understood by those skilled in the art. For example, the signal flow diagram of FIG. 2 is described as an example in which the moving object travels on an inclined curve road. In the present invention, the signal flow diagram may be easily applied even when the moving object travels on an inclined straight road.

As described above, according to the present invention, when the position of the moving object is determined by reflecting the horizontal axis inclination and the longitudinal axis inclination of the road on which the moving object travels when the position of the moving object is determined by the dead reckoning due to the low reliability of the received position information signal. Can be determined more accurately.

When the dead reckoning algorithm is performed in the GPS shadowed area, the present invention compensates the error divergence caused by the error of the gyroscope with the detection signal of the 2-axis inclinometer, thereby eliminating the path deviation that may occur in the GPS shadowed area. It can be minimized.

In addition, since the dead reckoning reflecting the two-axis inclinometer of the present invention plays an important role in the navigation system, the overall performance of the navigation device can be improved through more accurate dead reckoning.

Claims (5)

(a) The control unit receives a horizontal axis inclination on the left and right sides of the moving object, a longitudinal axis inclination in the front and rear directions, a traveling angle displacement amount of the moving object, and a traveling distance information signal from the sensor unit, and calculates the traveling distance per unit time using the traveling distance information signal. process; (b) correcting the traveling angle displacement according to the received horizontal axis gradient and vertical axis gradient according to Equation 2 below; (c) correcting the driving distance per unit time according to the received horizontal axis gradient and vertical axis gradient according to Equation 1 below; And and (d) estimating the current position from the position of the previous time point of the movable body as the corrected traveling angle displacement amount and the corrected traveling distance per unit time according to Equation 3 below. Equation 2

Here, A is a traveling angle displacement amount of the corrected moving object, A _-1 is a traveling angle displacement amount at a previous time, Δθ is a traveling angle displacement amount of the moving object detected by the sensor unit, and θ _x is the horizontal axis inclination of the road. Equation 1

Here, D is the traveling distance of the corrected moving object, d is the traveling distance per unit time, θ _x is the horizontal axis inclination of the road, θ _y is the longitudinal axis inclination of the road. Equation 3

Here, P _x and P _y are the longitude and latitude coordinates of the corrected moving object, P _x-1 and P _y-1 are the longitude and latitude coordinates of the moving object detected before the unit time, and D is the mileage correction per unit time. The traveling distance per unit time of the moving body corrected in the process, A is the traveling angle displacement amount of the moving body corrected in the traveling angle displacement correction process. (a) receiving a position information signal received by the GPS receiver from the control unit and determining reliability; (b) determining the position of the moving object using the position information signal when the reliability is good; (c) When the reliability is not good, the sensor unit receives the transverse inclination and the longitudinal axis inclination in the front and rear directions of the moving object, the traveling angle displacement amount of the moving object, and the traveling distance information signal, and receives the traveling distance information signal. Calculating a driving distance per unit time; (d) correcting the traveling angle displacement according to the received horizontal axis gradient and vertical axis gradient according to Equation 2 below; (e) correcting the traveling distance per unit time according to the received horizontal axis gradient and vertical axis gradient according to Equation 1 below; And (f) determining a current position from a position of a previous time point of the moving body according to Equation 3 below using the corrected driving angle displacement and the corrected traveling distance per unit time; (g) a method of positioning a moving object comprising: mapping and displaying the position of the moving object determined in step (b) or the current position of the moving object determined in step (f) on a digital map. Equation 2

Here, A is a traveling angle displacement amount of the corrected moving object, A _-1 is a traveling angle displacement amount at a previous time, Δθ is a traveling angle displacement amount of the moving object detected by the sensor unit, and θ _x is the horizontal axis inclination of the road. Equation 1

Here, D is the traveling distance of the corrected moving object, d is the traveling distance per unit time, θ _x is the horizontal axis inclination of the road, θ _y is the longitudinal axis inclination of the road. Equation 3

Here, P _x and P _y are the longitude and latitude coordinates of the corrected moving object, P _x-1 and P _y-1 are the longitude and latitude coordinates of the moving object detected before the unit time, and D is the mileage correction per unit time. The traveling distance per unit time of the moving body corrected in the process, A is the traveling angle displacement amount of the moving body corrected in the traveling angle displacement correction process. delete delete delete

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