JPH0794986B2 - Distance correction device for self-contained navigation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) [0001] The present invention relates to a device for correcting a distance in self-contained navigation.

(Prior Art) Conventionally, for example, an odometer (distance meter) has been used as a device for calculating the traveling distance of a vehicle.

In this system, a speedometer is provided with a device for instructing the speed of the vehicle and a device for cumulatively displaying the traveled distance, and the driver is informed of the state of the vehicle every moment (Automotive Engineering Society, May 1983). Issued on 31st, refer to Vol. 7, Automotive Engineering Handbook).

However, in the method of calculating the mileage of the odometer, since the mileage is measured according to the number of rotations of the tire, the tire radius changes due to the centrifugal force, which causes an error in the measurement of the mileage, especially at high speeds. It is generally known to occur.

Therefore, as a odometer that corrects the error in mileage measurement, a measurement method is adopted in which one pulse is output for each rotation of the tire and the number of rotations of the tire is converted into the number of pulses, thereby measuring the mileage. However, when the traveling speed exceeds 80 km / h, one pulse is added every 32 pulses to cancel the measurement error.

(Problems to be Solved by the Invention) However, in the above-mentioned conventional odometer, it is simply
Since this is a correction method that adds one pulse for every measurement of 32 pulses, it cannot be said to be a complete correction, and especially when running a long distance in a high-speed driving range, the problem that a large error occurs with the increase of the distance is complete. It has not been resolved.

The present invention has been made in view of such an actual situation, and it is possible to always measure an error-free travel distance even when a long-distance travel is performed at a desired travel speed regardless of low speed travel and high speed travel. It is an object to provide a distance correction device for self-contained navigation.

[Means for Solving the Problems] (Means for Solving the Problem) In a distance correction device for self-contained navigation that calculates a current position after that based on an initial value of a vehicle position that has been input and set as a reference, a plurality of units corresponding to respective vehicle speeds are provided. According to the storage means 5 for storing the correction value of the traveling distance, the vehicle speed pulse detecting means 7 for detecting the vehicle speed pulse according to the traveling speed of the vehicle, and the output state of the vehicle speed pulse detected by the vehicle speed pulse detecting means 7. Selection means 6 for selecting a correction value of the travel distance from the storage means 5, output state of the vehicle speed pulse detected by the vehicle speed pulse detection means 7, and correction of the travel distance selected from the storage means 5 by the selection means 6. A mileage measuring means 8 for measuring the mileage of the vehicle based on the value and a map match or
Coordinate detection means for detecting the coordinates indicating the position of the vehicle by the longitude, latitude or coordinates on the map obtained from the GPS receiver or position beacon, and the straight line of the vehicle from the previous coordinates and the current coordinates detected by the coordinate detection means A first calculating means 1 for calculating a traveling distance and a second calculating means 2 for detecting a traveling distance and an azimuth angle of a vehicle to calculate a straight traveling distance of the vehicle.
And a comparing means 3 for comparing the linear traveling distance of the vehicle calculated by the first calculating means 1 with the linear traveling distance of the vehicle calculated by the second calculating means 2, and based on the comparison result of the comparing means 3. And correction means 4 for correcting the correction value of the travel distance to be selected from the storage means 5 by the selection means 6 to an optimum correction value, and the travel distance measuring means 8 has the correction value of the travel distance by the correction means 4. Is corrected, the traveling distance of the vehicle is measured based on the vehicle speed pulse and the corrected correction value of the traveling distance.

(Operation) Comparing the calculated value of the straight running distance of the vehicle by the coordinate comparison of the previous time and this time with the calculated value of the straight running distance of the vehicle according to the running distance of the vehicle and the azimuth, the optimum for the present running distance from the storage means Since a correct correction value is selected and the actual mileage is measured, it is possible to always measure the mileage without error even when performing long-distance traveling at a desired traveling speed regardless of low speed traveling or high speed traveling. it can.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a block diagram showing a main configuration of a distance correction device in self-contained navigation according to the present invention.

Reference numeral 1 denotes a first calculation means, which includes coordinate detection means for detecting coordinates indicating the position of the vehicle based on external information obtained from a map match, a GPS receiver, or a position beacon, and detects the vehicle position in the previously detected coordinates and this time. The straight running distance of the vehicle is calculated by taking the difference from the vehicle position in the coordinates.

Reference numeral 2 denotes a second calculating means, which detects each traveling direction component in the x direction and each traveling direction component in the y direction in the traveling section when the vehicle travels in a predetermined section, and calculates the sum of the two. Then, the straight running distance of the vehicle is calculated.

Reference numeral 3 denotes a comparison means, which performs a predetermined calculation described later in detail, and compares the linear traveling distance of the vehicle calculated by the first calculating means 1 with the linear traveling distance of the vehicle calculated by the second calculating means 2. , Generates an error signal (comparison value) representing an error in measurement.

Reference numeral 4 is a correction means, which takes in the error signal of the comparison means 3, and is related to each reference value (for example, each speed, that is, 1 Km / h to 180 Km / h, which is stored in a storage unit (speed table) 5 described later in detail. (A numerical value for each speed, which is divided for each acceleration of 1 Km / h)
Correct (select again) the optimum value (correction value Cx) for correcting the mileage from each value (correction value Cx) corresponding to. The corrected numerical value (correction value Cx) is transferred to the traveling distance measuring means described later.

Reference numeral 6 denotes a selection unit, which selects a correction value for the traveling distance from the storage unit 5 according to the output status of the vehicle speed pulse detected by the counter (vehicle speed pulse detection unit) 7, but selects the correction value for the traveling distance from the correction unit 4. When there is a notification that the correction is made, the correction value of the traveling distance corresponding to the notification of the correction is selected from the storage means 5.

Reference numeral 8 is a traveling distance measuring means, and the detection value of the pointer 9 is obtained from the numerical value (correction value Cx) transferred from the storage means (speed table) 5 by the correction means 4 and the count value obtained by the counter 7 when the vehicle speed pulse is generated. The traveled distance is measured by multiplying the subtracted value by a reference value related to the current traveling speed. The measurement result is displayed on the display means 10.

FIG. 2 is a flowchart of steps # 1 to # 8 in FIG. 1, FIG. 3 is a flowchart of steps # 9 to # 12, and FIGS. 4 and 5 are explanatory diagrams of the calculation method.

Hereinafter, the steps will be specifically described with reference to FIG.

(1) First, map matching and GPS (GlobalP
ositioningSystem) Confirm and correct the position with a receiver, position beacon, etc.

(2) The reference position, that is, the latitude, longitude or coordinates on the map is stored and set together with the direction. At this time, the azimuth is 0 °. At this time, the reference position is stored as the memory 1-1, and the azimuth is stored as the memory 1-2.

(3) The pulse counter 7 and the pointer 9 (vehicle speed counter at the time of sampling) of the vehicle speed meter are set.

The vehicle speed counter 7 constantly counts up when a vehicle speed pulse is generated. At this time, the vehicle speed counter 7 and the pointer 9 are stored as the memory 2. Note that only the pointer 9 is set during sampling.

(4) The average speed is calculated by the memory 2 for each sampling. At that time, the reference value of the speed table as the memory 3 is adopted.

(5) The travel distance Δd is calculated from the speed table 5.

A ... [(Counter)-(Pointer)] Reference value = Running distance = Δd R ... Reference value of speed table 5, that is, Cx Cx ... Ci to C ₁₈₀ A × Cx = Δd The table is for standard air pressure and standard dynamic load. The speed table 5 has a reference value R when the offset value described below is determined.
Is corrected, and the corrected new speed table 5 is stored as the memory 3.

(6) By referring to the memory 1-2, the azimuth angle θ ° for each sampling is read and detected.

(7) Referring to FIG. 4 from the traveling distance Δd and the azimuth angle θ °, the component y in the traveling direction at each sampling between the two points PQ
And the orthogonal component x.

Δd × cos θ = y Δd × sin θ = x (8) The above x and y are added and stored in the memory 4 (see FIG. 4). When the above is completed, the vehicle is stopped and the position correction is not performed at that time. If it is sufficient, the operation described in (3) again, that is,
The vehicle speed counter 7 and the pointer 9 are set by the pulse of the vehicle speed meter, and the above steps are repeated again. On the other hand, if sufficient, proceed to the next.

Next, the subsequent steps of FIG. 3 will be described in order of steps.

(9) Corrected position coordinates between the old position and the new position (latitude,
The straight-line distance is obtained D by the longitude or the coordinates on the map and the memory 1-1).

(10) The position is stored in the memory 2-1 and the azimuth is stored in the memory 2-2, as in the above item (2).

(11) Comparing the distances calculated in (8) and (9).

(See Figure 5) (12) The reference value R of the offset value is corrected by the comparison value C.

R × C = R (comparison correction value) This comparison correction value is returned to the above item (3) and the process is repeated,
The error between the distance traveled and the straight line distance between two points measured on the basis of information on the map or from the outside is eliminated to obtain an accurate distance traveled.

As described above, the distance correction device in the self-contained navigation of the present embodiment has the traveling distance calculated based on the standard air pressure of the tire radius and the reference value for the speed change at the reference dynamic load as described above, and on the map. Or information from outside (GPS
2 based on the receiver or position beacon)
Since the error (comparison value) is obtained by comparing with the linear distance between the points and the reference value is corrected by this error (comparison value), the error between the distances is eliminated by this correction value,
The exact distance can be calculated.

Although the embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and even if there is a design change or the like within a range not departing from the gist of the present invention. Included in the present invention.

[Effects of the Invention] As described above, according to the present invention, the calculated value of the straight running distance of the vehicle by the coordinate comparison between the previous time and this time and the calculated value of the straight running distance of the vehicle by the running distance and the azimuth angle of the vehicle. The optimum correction value for the current mileage is selected from the storage means and the actual mileage is measured, so that long-distance traveling at a desired traveling speed is performed regardless of low speed traveling or high speed traveling. Even if it goes, it is possible to obtain an effect that it is possible to always measure the traveling distance without error.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main configuration of a distance correction device in self-contained navigation according to the present invention, FIG. 2 is a flowchart of the former stage of FIG. 1, FIG. 3 is a flowchart of the latter stage, FIG. 4 and FIG. FIG. 5 is a basic diagram for the calculation means of the distance correction device in the self-contained navigation of the present invention.

Claims (1)

[Claims] 1. A distance correction device for self-contained navigation in which a current position is calculated based on an initial value of a vehicle position set by human power, and a plurality of correction values of traveling distances corresponding to respective speeds of a vehicle are stored. A storage unit, a vehicle speed pulse detection unit that detects a vehicle speed pulse according to the traveling speed of the vehicle, and a correction value for the traveling distance selected from the storage unit according to the output state of the vehicle speed pulse detected by the vehicle speed pulse detection unit. Selecting means for measuring the traveling distance of the vehicle based on the output state of the vehicle speed pulse detected by the vehicle speed pulse detecting means and the correction value of the traveling distance selected by the selecting means from the storage means. Coordinate detection that detects the coordinates indicating the position of the vehicle by means and the longitude, latitude or coordinates on the map obtained from the map match or GPS receiver or position beacon. Means, first calculating means for calculating the linear traveling distance of the vehicle from the previous coordinates and the present coordinates detected by the coordinate detecting means, and the linear traveling distance of the vehicle by detecting the traveling distance and the azimuth angle of the vehicle. A second calculating means for calculating the linear traveling distance of the vehicle calculated by the first calculating means and a linear traveling distance of the vehicle calculated by the second calculating means; Correction means for correcting the correction value of the travel distance to be selected from the storage means by the selection means to an optimum correction value based on the comparison result of the comparison means; and the travel distance measurement means, When the correction value of the traveled distance is corrected by the correction means, the traveled distance of the vehicle is measured based on the vehicle speed pulse and the corrected correction value of the traveled distance. apparatus.