JP2522227B2 - Travel position display device for vehicles - Google Patents

Description

Detailed Description of the Invention [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention determines the position of a moving vehicle.
The present invention relates to a vehicle running position display device that is displayed overlaid on a map.
Vehicles that are calculated from various sensors, especially
It is effective for correcting the position error. [0002] 2. Description of the Related Art Conventionally, a vehicle has a direction sensor and a vehicle speed sensor.
These sensors are used to detect the direction and direction of travel of the vehicle.
It is known to determine the position of a vehicle by determining the distance traveled.
You. Then, based on this position, it is displayed on the CRT screen.
It is also known to display the position of the vehicle on the displayed map.
You. [0003] However, the azimuth section
A slight error is included in the detection value of the sensor or the vehicle speed sensor.
Therefore, the calculation of the vehicle obtained by integrating these outputs
A large error occurs in the position. The present invention has been made in view of the above problems
It was done with a simple structure
And pull the calculated position of the vehicle to the specified point on the map.
The purpose is to make the displayed vehicle position accurate.
You. [0004] The present invention solves the above problems.
To determine, set it on the road map as shown in Figure 1.
The moving distance from the start position and the moving direction are integrated, and
A calculator that calculates the distance traveled from the start position and the calculated position
Stage and the starting position when the calculating means starts calculation
And the initial setting means to set on the road map
Storage means for storing the positions of a plurality of feature points
Among the characteristic points, the vehicle is facing regardless of the traveling route.
The target feature points that are
The target detection means that is output and the calculated position
The curvature calculation means for calculating the curvature and the curvature calculation means
Of the curvatures calculated by
Maximum calculator that calculates the maximum curvature point indicating the given calculation position
And a first step for determining whether the target feature point is an intersection.
Judgment means and judges whether the maximum curvature is larger than a predetermined value
The second determination means that performs
Third judgment to judge whether it is within a predetermined range from the position of the sign point
Means and the judgments of the first to third judgment means are all true
At some time, the start position is updated to the position of the target feature point
Update means for displaying the calculated position on the road map
And a display means. [0005] As described above, according to the present invention, the target feature points
It is judged whether or not is an intersection by the first judgment means, and the maximum curvature
Is determined by the second determination means to determine whether
Whether the large curvature point is within a predetermined range from the position of the target feature point
It is judged by the judgment means of No. 3 and judged by the first to third judgment means.
When all the settings are true, the start position is set to the position of the target feature point.
I am updating. In the first determining means, the target feature point is the intersection.
Is determined. This allows vehicles to cross the intersection.
It is determined to have. Vehicle by the second determination means
It was determined that the maximum curvature during driving was greater than the specified value.
Set. As a result, the vehicle is traveling straight ahead at the intersection.
Instead of judging that you have made a right or left turn at the intersection
Is. The third determining means is a device that gives the maximum curvature.
The calculated position is within the predetermined range set as the target feature point.
Is determined. As a result, the maximum curvature point is azimuth,
It is determined that the location is at the intersection. And the
When the judgments of the first to third judgment means are all true,
Is the maximum curvature point when the vehicle passes the intersection
When is within the predetermined range from the position of the intersection,
The start position used as the reference for the calculation is updated to the position of the intersection.
The position where the curvature becomes maximum when passing through the intersection by turning right or left
Corresponds to the position of the intersection, so the maximum curvature value
By pulling in and setting this position as the new start position,
It is possible to prevent accidental pulling in when passing a right or left turn.
Wear. [0008] EXAMPLE An example to which the present invention is applied will be described. Ma
First, the configuration of this embodiment will be described with reference to the drawings. Figure
Reference numeral 1 is a block of a vehicle traveling route display device according to this embodiment.
It is a block diagram. The components shown in FIG. 1 are mounted on a vehicle.
However, by providing only the direction sensor and the vehicle speed sensor in the vehicle,
The data is transmitted by the communication device and the vehicle position is determined by the fixed station.
May be reproduced. The direction sensor 1 detects the traveling direction of the vehicle.
In this embodiment, the geomagnetic field is detected and the azimuth is detected.
Is used. However, as this direction sensor
Is due to the gyro compass and the turning of the left and right steering wheels.
Accumulate the steering angle of the vehicle obtained from the difference
It may be one that obtains the bearing. Vehicle speed sensor 2 is the vehicle
Is to detect the traveling speed of the
By processing, the traveling distance of the vehicle is obtained. The map memory 3 is a compact disc or the like.
It is a large-capacity storage device. In this map memory 3, for example,
For example, a certain area such as Tokyo, Aichi prefecture or Tokai region
The map data and the feature point data that describes the features of the road
Remembered Map data is road shape, road width, road
A device for reproducing maps such as road names, buildings, place names, and terrain.
Data. The feature point data is the displayed vehicle position and direction.
Driving direction obtained from position sensor 1, vehicle speed sensor 2
Map data is provided to correct the traveled distance
Is data created based on actual measurement. This practice
In the example, the road is approximated by a collection of linestrings and each line
The feature points are the end points and intersections of roads. And
The following information as data about these characteristic points
have. Feature point number Absolute position (latitude / longitude) of feature point P_t. Area number containing the feature point Angle formed by polygonal lines on both sides of the feature point (curvature θ) The number of other feature points connected to the feature point (i; 1
m) The number of other feature points connected to the feature point Distance to other feature points connected to the feature point
(D_i) Direction (α to other feature points connected to the feature point_i) (However, the area number is, for example, divided into several parts of Japan.
If you do, there are as many partition numbers ,. ) If the road continues without branching, the feature points will be
Is determined. The control switch 4 is the first driver
You can enter the period price and select the map to be displayed.
Various switches are provided. Micro Computer
The data 5 includes a direction sensor 1, a vehicle speed sensor 2 and a control.
The position of the vehicle can be determined from the initial value input from switch 4.
calculate. Then, the calculated position and the map data are C
Input to the RT controller 6. The CRT controller 6 displays the CRT 7
Control. Location transferred from the microcomputer 5
When the figure data is reproduced as a map on the screen of CRT7,
The calculation of the vehicle transferred from the microcomputer 5
Display the location on the currently displayed map. Then this fruit
The operation of the embodiment will be described with reference to the drawings. 2 to 5 show a microcomputer 5
5 is a flowchart showing the operation of the above. Micro Computer
The data 5 operates when a power switch (not shown) is turned on.
To stop when the power switch is cut off. 2,
FIG. 3 shows a process of correcting the calculated position according to the present invention in this embodiment.
It is a flow chart which shows a reason. CRT controller 6
The display command processing for is repeated every predetermined time shown in FIG.
It is executed according to the display interrupt flowchart. Control
When the roll switch 4 is operated, the switch shown in FIG.
The flow chart of the switch interrupt is executed. In this embodiment, the calculated position of the vehicle is the starting position.
The product of the traveling direction from the vehicle and the traveling distance in this traveling direction
Calculated from arithmetic. And this starting position is shown in FIG. 2 and FIG.
The absolute position of the target feature points
The driving direction and running from this new start position
Calculate the calculated position by integrating the distance and. In FIG.
When the power is turned on, step 101 is executed and the memory and
Dista etc. are initialized. In step 102, the vehicle
The process of setting the initial position is performed. Here the crew
Operates control switch 4 to display on CRT 7
Select the map to be displayed and indicate your vehicle position on this map.
Shall be shown. In addition to this, the last vehicle stop
The calculation position at time is stored in the non-volatile memory and
The position may be set as the initial position. In step 103
Is the initial target feature point P _tDecision is made. That is,
Characteristic point P where the vehicle is heading_tFrom the feature point data
Search. Here, the direction sensor 1
Among the feature points in the direction of the vehicle
Period target feature point P_tAnd In step 104, the settings in step 102 are set.
Initial target feature point with the determined initial position as a temporary feature point
P_tThe distance d to is calculated. In addition, this step
In step 104, the feature points and targets passed from the feature point data
Feature point P_tTo find the distance to. In step 105,
The radius r of the test circle is calculated. Here, as shown in FIG.
The radius r of the constant circle gradually increases as the mileage increases.
Turn left or right at the intersection or go through a bend.
Each time you pass, multiply the mileage to calculate the radius of the test circle again
Start counting. In this embodiment, the verification circle radius r is calculated from the following formula.
Calculate R = K₁・ Dis + K₂・ Σdis + r_O K₁, K₂Constant (K₁> K₂) dis; distance between feature points Σdis; Distance from the intersection or inflection point r_OInitial value (minimum test circle radius) In step 106, the initial target feature point (target feature point) P
_tIf is an intersection or a bend, then YES. If not,
Branch to NO. In the case of NO, that is, one target feature point P
If it is a road point, perform steps 107 to 111.
Run. In step 107, the above-mentioned initial position is set.
Or, the calculated position P is calculated by adding up from the previously passed feature points.
And the travel distance D is calculated. In step 108,
The mileage D calculated in step 107 is calculated in step 104.
If it is larger than the calculated feature point distance d,
Returns to step 107. In step 109, traveling
Calculated position P when the distance D becomes the feature point distance d_dPlayed
Calculate In step 110, obtained in step 109
Calculation position P_dIs the target feature point P_tIs it within the test circle of
To determine. If not, the flowchart of FIG.
Move on. In step 111, the calculation position P_dThe goal
Feature point P _tPosition and the calculation position after that is the target feature.
Point P_tIt is calculated by adding up from. These steps
By the processing of steps 107 to 111, the feature point P shown in FIG.
_t0, P_t1, P_t2, P_t3, P_t4Will be pulled in. If YES in step 106,
That is, the target feature point P_tIs an intersection or a turning point
If it is determined, the processing of steps 114 to 121 is executed.
To go. In step 114, the above-mentioned step 107 and
Similarly, the calculated position P and the traveling distance d are calculated. Steps
In 115, 116, 117, the traveling distance D is (dr)
When it is more than and equal to or less than (d + r), it is determined in step 114.
Calculation position P_mAnd the two calculated positions P obtained by this
_n-1, P_n-2From, the previous calculation position P_{n- 1}Curvature of
Ask for. Here, as shown in Fig. 7 (a), the straight lineNumber 1And straight
lineNumber 2Angle θ_n-1Is calculated. The mileage D is (d
-R) or more, the process proceeds to step 118. [0021] (Equation 1) [0022] ## EQU00002 ## In step 118, steps 114 and 11
Curvature θ calculated in the loop of 5, 116, 117_n-1Horse
The maximum value θ_n-1And its calculated position P_n-1Up to
Large curvature θ_MAnd the maximum curvature point Pθ. Ste
In 119, this maximum curvature θ_MIs the predetermined value θ_TGreater than
It is determined whether or not, and if not, the process branches to step 109.
This means that when the curvature is below a certain value (eg 20 °),
Go straight through the difference point or bend the curve at the bending point to fill the road width
It is used as a curved road and moved to the same process as a straight road.
It is. In step 120, the maximum curvature point Pθ is the target
Feature point P_tIf it is in the test circle of
The process moves to the flowchart of FIG. 3 described later. In step 121
Is the position of the maximum curvature point P.theta._tThe position of
You. Then, the calculated position thereafter is the target feature point P_tFrom
Calculated by adding up. These steps 114 to 12
By the processing of 1, the characteristic point P shown in FIG._t3, P_t5Withdrawal
Only is done. At step 112, azimuth correction is performed.
In this embodiment, a magnetic sensor that detects geomagnetism is used as an orientation sensor.
Although an azimuth sensor is used, the declination of the geomagnetism and the magnetization of the vehicle body
Causes a slight error. Also, as a direction sensor,
The one that integrates the angular acceleration obtained from the gyro sensor,
Uses one that detects a change in azimuth based on the rotation difference between the left and right wheels.
If there is an error in the direction of the
It will be accumulated in various ways. Therefore, in this embodiment, as shown in FIG.
The characteristic point P that passed the previous one_{t- 1}And the target feature point P_t
A straight line P connecting to_t-1, P_tAnd feature point P_t-1And steps
111 or the target feature point P in step 121_tPull in
The calculated position P_d, Or a straight line connecting PθNumber 3When
Find the angle φ formed by. And from the subsequent direction sensor 1
The position is obtained by adding the correction by this angle φ to the obtained azimuth α
Used as the bearing for calculation. [0025] ## EQU3 ## In step 113, the next target feature point P_tDecided
Set. This target feature point P_tIf is not an intersection,
The following feature points can be easily obtained from the feature point data. intersection
Then, the target feature point is determined by the processing described below. Ma
No, this target feature point P_tFeatures other feature points that connect to
Obtained from point data. The closest of these feature points
Distance to feature point d_minAsk for. The traveling distance D from the target feature point P this time is
d_minThe calculated position P when / 2 is obtained. Of this time
Target feature point P_tAnd the straight line P connecting the calculated position P_t, P
Ask for rank. This target feature point P_tFeature points connected to
Of these, the feature point closest to this direction will be
Target feature point P_tAnd In step 110 or 120 of FIG.
When it branches to O, the process moves to the flowchart of FIG. Figure 3
A row chart is a road whose vehicles are not converted to map data.
Or a process that is executed as if you are driving in a parking lot
It makes sense. In step 122, the calculated position P is obtained.
In step 123, the feature point P closest to the calculated position P
_PTo calculate. In step 124, in step 123
The calculated characteristic point P is used as a provisional target characteristic point.
Is the feature point P_pIt is judged whether it is within the test circle of
Then, the process returns to step 122. From step 125 to step 128,
The azimuth α obtained from the azimuth sensor 1 is the characteristic point P_PConnected to
All feature points P_iDirection to α_iOne of
If not, move to step 129.
You. In step 129, calculated in step 122
The calculated position P is the feature point P_PChange to the position and pull in
You. In this embodiment described above, the calculation position P
Target feature point P_tTo determine whether to pull in
Whether the line distance D and the feature point distance d match,
Position P is the target feature point P_tWhether or not it is within the test circle r of
It is judged by one of them.
Not executed Based on these judgments, the vehicle is parked outside the road.
Incorrect while driving on a parking lot or a road that has not been converted to map data
To prevent accidental retraction and display on the CRT7 due to incorrect retraction.
Decrease the display error and the error accumulated in the subsequent position calculation.
And a highly practical vehicle running position display device.
You can Also, each time the drawing is performed at the feature point, the direction
The error φ of the azimuth α obtained from the sensor 1 is calculated, and the subsequent position
In the calculation, since the position is calculated by adding the correction by φ,
Accumulation of errors due to the direction sensor can be prevented.
Also, the target feature point P_tIs an intersection or a bend
If the travel distance D is equal to or smaller than the verification circle radius r before and after the feature point distance d,
Maximum curvature θ while in_MAsk for. And this maximum
Curvature θ is a predetermined value θ_TIt is above, and it became the maximum curvature
There is an intersection only when the calculated position P when is within the test circle
Or, pull in to the bending point. This makes it possible to cross
Or, the bending point can be accurately determined, resulting in an incorrect determination.
Prevents accidental retraction.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram of an embodiment to which the present invention is applied. FIG. 2 is a flowchart showing the operation of the microcomputer of the embodiment. FIG. 3 is a flowchart showing the operation of the microcomputer of one embodiment. FIG. 4 is a flowchart showing an operation of the microcomputer of the embodiment. FIG. 5 is a flowchart showing the operation of the microcomputer of the embodiment. FIG. 6 is an explanatory diagram illustrating an operation of one embodiment. FIG. 7 is an explanatory diagram illustrating an operation of one embodiment. [Description of Signs] 1 Direction sensor 2 Vehicle speed sensor 3 Map memory 4 Control switch 5 Microcomputer 6 CRT controller 7 CRT

Claims (1)

(57) [Claims] (1) Computation means for accumulating a movement distance and a movement direction from a start position set on a road map, and calculating a traveling distance from the start position and a calculation position, Initial setting means for setting the start position when the calculation means starts calculation, storage means for storing the positions of a plurality of feature points set on the road map, among the plurality of feature points Target detecting means for detecting a target feature point that the vehicle is heading and may pass regardless of the travel route, curvature calculating means for calculating a curvature of a calculation position during traveling of the vehicle, and the curvature calculating means A maximum calculation means for calculating the maximum curvature and a maximum curvature point indicating a calculation position giving the maximum curvature, and a first determination means for determining whether or not the target feature point is an intersection. The above Second determining means for determining whether or not a large curvature is larger than a predetermined value; third determining means for determining whether or not the maximum curvature point is within a predetermined range from the position of the target feature point; Update means for updating the start position to the position of the target feature point when all the determinations by the first to third determining means are true; and display means for displaying the calculated position on a road map. A vehicle traveling position display device characterized by the above.