JP2907937B2 - Moving object position detection device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position detecting device for a moving body (hereinafter, referred to as a moving body) such as a vehicle suitable for use in an automobile navigation system.

[Conventional technology]

2. Description of the Related Art Navigation systems for providing information such as current position information required for a moving body to efficiently reach a destination to a driving driver have been actively developed.
Conventionally, three methods such as self-contained navigation, GPS navigation, and close proximity wireless navigation have been known as position detection methods for knowing the current position of a moving object.

The self-contained navigation includes dead reckoning navigation and map matching navigation. Dead reckoning is a method of accumulating and calculating the moving direction and moving distance of a moving object based on the detection outputs of a direction sensor and a distance sensor provided on the moving object, and adding these to the coordinates of the starting point. The map matching method is a method in which a moving trajectory obtained by dead reckoning is collated with a road map, and a cumulative error in dead reckoning is corrected.

In the above GPS navigation, signals from a plurality of GPS (Global Positioning System) satellites are received by a GPS receiver provided on the mobile object,
In this method, the current position is known by calculating the distance from each satellite based on the transmission delay time of each signal.

The close proximity wireless navigation is a method of correcting an error in dead reckoning navigation based on position information from a sign post provided at a key point on a road.

As a technique related to the present invention, for example,
There is a technology disclosed in Japanese Patent Application Laid-Open No. 171377/1988 and Japanese Patent Application Laid-Open No. 63-148115.

[Problems to be solved by the invention]

Conventional methods for detecting the position of a moving object include the above.However, in the above-described self-contained navigation, it is necessary to input the coordinates of the starting point.In the case of dead reckoning navigation, sensor errors are accumulated during traveling. Therefore, there is a disadvantage that the detection accuracy is poor.
The above GPS navigation also has the disadvantage that the detection accuracy is poor and it is difficult to identify which road you are on. In addition, the above-mentioned proximity wireless navigation has drawbacks such as requiring ground facilities such as a sign post. As described above, each of the conventional position detection methods has disadvantages, and it has been an issue to realize a position detection method with as few defects as possible.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has as its object to obtain a position detecting device for a moving object having better detection accuracy.

[Means for solving the problem]

The invention according to claim (1) shows a GPS receiver for receiving a signal from a satellite and an elliptical or rectangular error range including the position of the moving object by performing a predetermined operation based on the received signal. It is composed of a GPS calculator that outputs position data, a map data memory that stores map data, an azimuth sensor and a distance sensor that are provided on the moving body, and obtains a moving trajectory of the moving body from a signal obtained by the sensor. And a map matching calculator for determining the current position of the moving object based on the moving trajectory, the map data, and the position data indicating the error range output from the GPS calculator. The position is determined.

According to a second aspect of the present invention, there is provided a GPS receiver for receiving a signal from a satellite, and a GPS for outputting a position data indicating an error range including a position of a moving body by performing a predetermined operation based on the received signal. It consists of an arithmetic unit and an azimuth sensor and a distance sensor provided on the moving body. A moving trajectory of the moving body is obtained from a signal obtained by the sensor, and a plurality of positions are obtained based on the moving trajectory and the map data. in case of
The current position of the moving object is selected and determined from the position calculation unit and the data from the map data memory that stores the map data. Things.

[Action]

As described above, the detection of the position of the moving object in the invention according to claim (1) is performed by performing a predetermined calculation based on a signal received by the GPS receiver to thereby obtain an elliptical or rectangular error range including the position of the moving object. Output position data indicating
A GPS calculator, a map data memory for storing map data, an azimuth sensor and a distance sensor provided on a moving object,
The trajectory of the moving object is obtained based on the azimuth and the moving distance obtained from the sensors, and the current position is determined based on the trajectory, the map data, and the position data indicating the error range output from the GPS calculator. Is determined, the first position from the position of the moving object including the error range is set as the actual moving position.

The position detection of the moving object in the invention of claim (2) performs a predetermined calculation based on a GPS receiver provided on the moving object and receiving signals from a plurality of GPS satellites and a signal received by the receiver. Thus, a GPS calculator that outputs position data indicating an error range including the position of the moving object, an azimuth sensor and a distance sensor provided on the moving object, and a moving azimuth and a moving distance obtained from the azimuth sensor and the distance sensor When a plurality of positions are obtained based on the movement trajectory and the map data, the moving object is obtained from among the plurality of positions based on the position data obtained from the GPS calculator. The position calculation unit that selects / determines the current position of the map and the map data memory that stores the map data allow the unnecessary position to be quickly removed from among the multiple positions to reduce the actual movement position. It is constant.

〔Example〕

The principle of the present invention will be described below. As shown in FIG. 2, one of three GPS satellites GPS1, GPS2 and GSP3 is used.
The transmission time of the radio wave from one satellite is measured, and the pseudo distance L from the satellite to the moving object is obtained. Next, the satellite position (U, V, W) is obtained based on the orbit data transmitted by the satellite. Here, assuming that the position coordinates of the moving object are (X, Y, Z) and the error between the clock of the moving object and the clock of the satellite is A, the following positioning equation is established.

Three satellites GPS1, GPS2, GSP3 each upright the positioning equations, by solving them as simultaneous equations to determine the first position p ₁ of the moving body as in the second figure. However, the altitude Z of the moving object is assumed to be known. Actually, the above (U, V,
Since W) includes an error, a true position exists in a circle B having a radius d indicating an error range.

Then based on the first position p _1, call map data as in the third view showing the vicinity of a circle B of the radius d, and circle B data including the same position p ₁ of the first Compare.
The map indicated by the map data includes a road a and roads b and c branched from the road a as shown in the figure. The map and by matching the above circle B, it is assumed that the moving body portion both overlaps are present and the position at the shortest distance 1 from the first position p ₁ of the overlapping portion and the second position p ₂ ,
The position p ₂ of the second to the current position of the moving body. In the case of FIG. 3, it is assumed that a road c is included in a portion where the map and the circle B intersect, and a moving object exists on the road c. Then, in a portion included in the circle B of the road c, the first
The position at the shortest distance ₁ from the position p ₁
The position p ₂ of.

FIG. 1 shows an embodiment of a movement position detecting device based on the above principle.

In FIG. 1, reference numeral 1 denotes a GPS receiver provided on a mobile body (not shown) for receiving signals from the satellites GPS1, GPS2, and GSP3 via an antenna 1a, and 2 denotes a reception signal from the GPS receiver 1. Based on the above formula (1), the first position is calculated.
GPS arithmetic unit for outputting a first position data indicating a circle B of radius d including p _1, 3 is the first reading map data indicating a map of its vicinity based on the position data of the to the map data memory, 4 by matching the read-out map data and the first position data from the map data memory 3, the map matching calculator for calculating the second position data indicating a second position p _2, 5 is the first This is a display for displaying the position p2 of No. ₂ on a map.

 Next, the operation will be described.

The GPS computing unit 2 receives each satellite GPS1, G received from the GPS receiver 1.
PS2, by performing calculation based on the reception signal from GSP3, outputs the first position data indicating a circle B of radius d including the first position p ₁ as shown in Figure 2. Based on the first position data, map data indicating a map near the circle B, for example, map data including roads a, b, and c in FIG. 3, is read from the map data memory 3. Map matching calculator 4
In, the first position data and the map data are matched as shown in FIG. Then, the road c included in the circle B is obtained, and the first position on this road c is determined.
second position p ₂ is determined to be the shortest distance 1 from p _1, second position data consisting of data and the map data indicating the second position is outputted. Thus, in the display device 5, the road a, b, together with the map of c is displayed, the second position p ₂ are displayed as the current position of the moving body on the road c.

That is, the present invention uses both the map matching navigation and the GPS navigation among the self-contained navigations described above.

FIG. 4 shows an embodiment of a moving object position detecting apparatus based on the above principle, and portions corresponding to those in FIG.

In Figure 5, now moving body has moved the moving track e indicated by the dotted line starting from the start point p ₀ in the direction of the arrow.
The map matching navigation will be sequentially added to the coordinates of the starting point p ₀ for the moving azimuth and the travel distance is input in advance is accumulated based on the measurement of the azimuth sensor and distance sensor in accordance with this movement, whereby the trajectory e Is required. Related map data is read out based on the locus e, and in the case of FIG. 5, map data including roads a, b, and c is read out. In this case, the current position is displayed on the assumption that the moving object exists on the road a close to the trajectory e, although it is the actual trajectory e. When the moving body passes the road a, the trajectory e becomes the road b
Assuming that _one point is located approximately at the middle point e between the points
It will not be possible to determine whether it is on the road or on the road c. At this time, two second positions p ₂₁ and p ₂₂ are generated.

On the other hand, by using a GPS navigation, from said positioning equations with (1), circle B of radius d including the first position p ₁ is determined. Next, this circle B is superimposed on the map including the two second positions p ₂₁ and p ₂₂ , one second position p ₂₂ in the circle B is determined as the current position, and the other second position p ₂₂ is determined. Delete the position p ₂₁ of.

As shown in Figure 6, the shape of the error range when located without biasing the囲Ri three satellites GPS1, GPS2, GSP3 is mobile (the first at position p ₁₎ is substantially circular B. On the other hand, as shown in FIG. 7, three satellites GPS1, GPS2, GSP3
Is offset to the moving body, the shape indicating the error range is an ellipse D. As shown in the figure, the angle between the vertical axis f and the major axis g is θ, and the radius of the major axis g is d.
This d is larger than in the case of FIG.
The ellipse D may be regarded as a rectangle.

Figure 8 shows a case where said overlaid ellipse D and road a, b, and c, and the second position p ₂₂ within the ellipse D it can be seen that effective. In the case of FIG. 5 described above, when the radius d of the circle B increases and becomes a circle B indicated by a virtual line in FIG. 8, both of the second positions p ₂₁ and p ₂₂ are circles. will fall within the B, and which one as the active is not the determine, by using the above ellipse D, it is possible to choose one of the second position p _22. In the case of carrying out another embodiment, FIG.
The GPS calculator 2 is an ellipse D (or rectangle) including the angle θ.
Will be output.

As described above, based on the moving direction and the moving distance obtained from the direction sensor 6 and the distance sensor 7 provided on the moving body, the map matching calculator 8 calculates the moving trajectory e in FIG. The data is read from the map data memory 3 and, for example, the two second positions p ₂₁ , p in FIG.
The second position data including ₂₂ is created and added to the comparator 9.
The comparator 9 compares the second position data with the first position data indicating a circle B having a radius d including the first position p ₁ obtained from the GPS calculator 2. And enable the second position p ₂₂ within circle B This comparison since it can be seen that to invalidate the other second position p _21, the map matching calculator 8 to that effect
Notify. Map matching computation unit 8 in response to this is to remove the other second position p _21, make the road a, b, c and display data representing a second position p _22, through the comparator 9 To display 5. Accordingly, the display device 5 road a, b, and displays a second position p ₂₂ on the road c as c and the current position.
In FIG. 4, the map operation unit 8 and the comparator 9 constitute a position operation unit.

〔The invention's effect〕

As described above, according to the invention of claim (1), based on the signal from the GPS satellite, the position data indicating the error range of the elliptical or rectangular shape including the position of the moving object is generated, and the position data is obtained from the direction sensor and the distance sensor. By calculating the obtained trajectory and comparing these position data with the related map data, the position of the moving object included in the error range is determined, so that the detection error of the conventional GPS navigation is compensated. As a result, the effect that the position can be detected with high accuracy can be obtained.

According to the invention of claim (2), based on a signal from a GPS satellite, position data indicating an error range including the position of the moving body is created, and movement from an azimuth sensor and a distance sensor provided on the moving body is performed. A moving path of the moving object is obtained based on the azimuth and the moving distance, and a position of the moving object is determined based on a plurality of position data obtained based on the moving path and the map data and position data obtained from the GPS calculator. If there are multiple moving object positions on the map indicated by the map data, it can be processed quickly to remove unnecessary objects and determine the actual moving object position with high accuracy. In addition to this, there can be obtained an advantage that an arithmetic unit having a relatively low capacity can be used.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a moving object position detecting device based on the present invention, FIGS. 2 and 3 are configuration diagrams for explaining the principle of the moving object detecting device, and FIG. FIG. 5 is a block diagram showing the position detecting device, FIG. 5 is a configuration diagram for explaining the principle of the device, and FIGS. 6, 7, and 8 are configurations for explaining the principle of the device based on the present invention. FIG. 1 is a GPS receiver, 2 is a GPS calculator, 3 is a map data memory, 4 is a map matching calculator, 6 is a direction sensor, 7 is a distance sensor, 8 is a map matching calculator, and 9 is a comparator. In the drawings, the same reference numerals indicate the same or corresponding parts.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-64-42000 (JP, A) JP-A-63-247613 (JP, A) JP-A-3-26913 (JP, A) JP-A 63-24713 247612 (JP, A) Akio Yasuda et al., “On GDOP and Positioning Error Distribution in GPS”, Transactions of the Society of Navigation, Japan, The Society of Navigation, Japan, September 25, 1988, No. 79, 25-31. Page (58) Field surveyed (Int. Cl. ⁶ , DB name) G01S 5/00-5/14 G01C 21/00

Claims (2)

(57) [Claims] An information processing apparatus includes: a GPS receiver provided in a mobile body for receiving signals from a plurality of GPS satellites; and a position of the mobile body by performing a predetermined operation based on a signal received by the GPS receiver. A GPS calculator that outputs position data indicating an error range of an elliptical or rectangular shape, a map data memory that stores map data, an azimuth sensor and a distance sensor provided on the moving object, and a directional sensor and a distance sensor. The moving trajectory of the moving object is obtained based on the obtained moving direction and moving distance, and the current position of the moving object is determined based on the moving trajectory, the map data, and the position data indicating the error range output from the GPS calculator. A position detecting device for a moving object, comprising: a map matching calculator for determining a position. 2. A GPS receiver provided in a mobile unit for receiving signals from a plurality of GPS satellites, and including a position of the mobile unit by performing a predetermined operation based on a signal received by the GPS receiver. A GPS calculator that outputs position data indicating an error range, an azimuth sensor and a distance sensor provided on the mobile object, and a movement of the mobile object based on a moving azimuth and a moving distance obtained from the azimuth sensor and the distance sensor. When a plurality of positions are obtained based on the movement trajectory and the map data while determining the trajectory, the current position of the moving body is determined from the plurality of positions by the position data obtained from the GPS calculator. A position detecting device for a moving object, comprising: a position calculating unit for selecting and determining; and a map data memory for storing the map data.