Navigation system utilizing locus data compression

A navigation system comprising:

• map information memory means for storing map information to be displayed;
• position determination means for determining a present position of a moving body in which the navigation system is mounted to generate present position data;
• azimuth detection means for detecting a traveling azimuth of the moving body;
• azimuth change detection means adapted for monitoring a traveling azimuth detected by said azimuth detection means to judge a change in the traveling azimuth, and detecting, as an azimuth changed position, the present position data when the traveling azimuth is changed;
• azimuth changed information memory means for obtaining the traveling azimuth and the azimuth changed position to generate data of coordinate values in a map display picture at the azimuth changed position and data of at least one of traveling azimuths before and after the moving body passes through the azimuth changed position and storing them as locus data which indicate a locus where said moving body has travelled in the past only as for azimuth changed positions, while the generated present position data and the detected travelling azimuth are not recorded as for positions other than the azimuth changed position;
• and
• display means adapted to obtain map information corresponding to the present position data from said map information memory means to display that map information and a present position, and to display the locus in the displayed map information by specifying a travel path to the azimuth changed position and a travel path from the azimuth changed position in the displayed map information according to the azimuth changed position and the travelling azimuth reproduced from the locus data stored in said azimuth changed information memory means.

A navigation system comprising:

• map information memory means for storing map information to be displayed;
• position determination means for determining a present position of a moving body in which the navigation system is mounted to generate present position data;
• locus data memory means for collecting and storing, as locus data which indicate a locus where said moving body has travelled in the past, the present position data at fixed periods, or every movement of a fixed distance;
• locus storage means for storing the collected locus data in a zone sectioned by a collection start point and a collection end point of the locus data with respect to a single zone or a plurality of zones;
• locus control means, which is operated according to an instruction from the external, for storing, into said locus storage means, locus data inside the collection zone collected in said locus data memory means together with information of the collection zone including the collection start point and the collection end point of that locus data, for erasing locus data outside the collection zone from said locus data memory means and for controlling the stored locus data;
• and
• display means adapted to obtain map information corresponding to the present position data from said map information memory means to display that map information and a present position, and to select locus data in a zone instructed by said locus control means out of the locus data stored in said locus data memory means or said locus storage means, thus to display the locus corresponding to the selected locus data in the displayed map information.

A navigation system comprising:

• map information memory means for storing map information to be displayed;
• position determination means for determining a present position of a moving body in which said navigation system is mounted to generate present position data;
• azimuth detection means for detecting a traveling azimuth of the moving body;
• azimuth change detection means adapted for monitoring a traveling azimuth detected by said azimuth detection means to judge a change in the traveling azimuth, and detecting, as an azimuth changed position, the present position data when the traveling azimuth is changed;
• azimuth changed information memory means for obtaining the traveling azimuth and the azimuth changed position to generate data of coordinate values in a map display picture at the azimuth change position and data of at least one of traveling azimuths before and after the moving body passes through the azimuth changed position and storing them as locus data which indicate a locus where said moving body has travelled in the past only as for azimuth changed position, while the generated present position data and the detected travelling azimuth are not recorded as for positions other than the azimuth changed positions;
• and
• locus storage means for storing the collected locus data in a zone sectioned by a collection start point and a collection end point of the locus data with respect to a single zone or a plurality of zones;
• locus control means, which is operated according to an instruction from the external, for storing, into said locus storage means, locus data collected and stored in said azimuth changed information memory means together with information of the collection zone including the collection start point and the collection end point of that locus data, for erasing locus data outside the collection zone from said locus data memory means and for controlling the stored locus data;
• and
• display means adapted to obtain map information corresponding to the present position data from said map information memory means to display that map information and a present position, and to select locus data in a zone instructed by said locus control means out of the locus data stored in said azimuth changed information memory means or said locus storage means, thus to display the locus corresponding to the selected locus data in the displayed map information.