JPS59152482A - Map display for vehicle - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a map display device for a vehicle that prevents the travel trajectory of a vehicle from deviating from a road on a map.

Recently, a map display device for vehicles has been developed that displays a map of the area in which the military is driving on a cathode ray tube, and displays the starting point, destination, current location, etc. on the map to be useful for road guidance. There is.

In addition, a map display device was developed in which a map printed on a transparent film was fixed to the surface of a cathode ray tube, and the trajectory of the vehicle was plotted and displayed along the roads on the map. There are also examples.

By the way, in the case of the latter map display device, the accuracy of the map,
As can be seen from the map display example shown in Figure 1, due to differences in the accuracy of the calculation unit (built into what is called a drive unit) that calculates and outputs the travel trajectory from various data, the vehicle If the travel trajectory of the vehicle deviates from road R on the map and there are many parallel roads, it may not be possible to accurately display which road the vehicle is traveling on. Note that P in the figure indicates the current position of the vehicle.

The present invention has been made in view of the above points, and in order to prevent the traveling trajectory of the vehicle from deviating from the road on the map in a vehicle map display device, a plurality of The vehicle receives a vehicle position correction signal transmitted from a transmitting part and corrects the current position of the vehicle on the display part to a predetermined position on the road closest to that point so that the traveling trajectory does not deviate from the road. It is something.

The present invention will be explained below based on the drawings.

Fig. 2 Vi shows an embodiment of the map display device according to the present invention, and 1 in the figure shows a system that uses a reed switch or a photocoupler to generate a pulse every time the vehicle travels a certain distance, and displays a pulse according to the vehicle speed. 1. A traveling distance measuring section such as a distance sensor that outputs a @ period pulse; 2, a traveling direction measuring section consisting of a geomagnetic sensor that detects the direction of the earth's magnetic field and knows the direction of the own army; 3, which is displayed on the map display section 5. A map storage unit such as a cassette tape or an IC memory that stores map data as digital data; 4 is a display unit for displaying a map based on data from a distance measurement unit 1, a direction measurement unit 2, and a map storage unit 3; A screen control section 5 controls the display, and 5 is a map display section that displays a map based on the data in the map storage section 3 and also displays the traveling trajectory of the vehicle. It will be done.

Reference numeral 6 denotes a receiving section that receives radio waves of a specific frequency emitted from a transmitter 7 that is carefully buried in a predetermined location on the road (for example, at an intersection), and is comprised of a receiving antenna and a receiving circuit installed under the floor of the vehicle.

Now, in the map display device having the above configuration, the screen control section 4 displays a map on the map display section 5 based on the map data from the map storage section 3, and also displays the map on the mileage measuring section 1.
Based on the travel distance data from the vehicle and the vehicle direction data from the travel direction measuring section 2, the travel locus of the own army is plotted on the map on the map display section 5 as shown by the broken line in FIG. In this process, when the vehicle passes an intersection while driving, the receiver 6 receives radio waves of a specific frequency transmitted from a transmitter 7 embedded in the intersection. The screen control section 4 calculates the position of the vehicle on the map based on the output of the receiving section 6 so as to move to the intersection closest to the current location, and sends a position correction signal to that effect to the map display section 5.

In the map display section 5, based on this signal, the vehicle position Pf on the map display section 5 is moved to the nearest intersection C2V from that position. If you do this, even if the driving trajectory temporarily deviates from road R on the map, it will be corrected for each intersection, so if the driving path deviates significantly from the road on the map, which road will it be? There is no need to worry about whether the vehicle is running or not. In addition, in the present invention, the accuracy of the drive guide and vehicle speed sensor is corrected while automatically correcting the current position of the vehicle repeatedly, thereby gradually increasing the accuracy of the traveling trajectory. can do.

[Brief explanation of the drawing]

Figure 1 shows an example of a map displayed by a conventional map display device;
FIG. 1-1 is a block diagram of a map display device according to the present invention, and FIG. 3 is an example of displaying a map by the map display device according to the present invention. 1... Traveling distance measuring section'', 2... Traveling direction measuring section,
3...-Map storage section, 4... Screen control section, 5
...Map display section, 6.Transmission section, 7.Transmitter patent applicant Hiroo Tsuchisuzuki, attorney for Nissan Jidosha Haishiki Company.

Claims (1)

[Claims] a storage means for storing map data; a detection means for detecting the travel distance and travel direction of the vehicle and outputting the detected travel distance as travel trajectory data; a map display means for displaying the travel trajectory of the vehicle; a reception means for receiving a device correction signal composed of a plurality of transmitters arranged at predetermined points along the road; A map display device for a vehicle characterized in that it has a position correction means for correcting the current position by moving the current position to a predetermined point closest to the current position on the road on the map based on the position correction signal.