Vehicle position detecting apparatus which comensates for errors in road map data matching operation

• US 5,552,990 A
• Filed: 05/31/1995
• Issued: 09/03/1996
• Est. Priority Date: 05/21/1991
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Yamashita, Mitsuhiro, Ihara, Yasuhiro, Ueyama, Yoshiki
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): LOUIS JACQUES, JACQUES H
• Application Number:
  US08/456,056
• Time in Patent Office: 461 Days
• Field of Search: 364/449, 364/444, 364/443, 364/450, 364/447, 364/460, 364/424.02, 364/424.01, 342/357, 342/176, 342/183, 342/184, 340/988, 340/990, 340/995, 340/905, 318/587, 73/178 R
• US Class Current: 701/208
• CPC Class Codes: G01C 21/30 Map- or contour-matching

Abstract

A correct vehicle position is detected even when the road data to be used in the map match computation includes errors of partial shape. When the matching computing operation of a running locus and the road data obtained from the outputs of a bearing sensor and a distance sensor and a non-match region has been effected by the map match computing means, the non-matching region of the road data and the running locus is detected. The positional error detection caused by errors of the road data is effected by prohibiting map integration.

Claims

1. A vehicle position detecting apparatus comprising:

a bearing sensor for detecting a running bearing of a vehicle;

a distance sensor for detecting a running distance of the vehicle;

a present position estimating means for estimating a present position of the vehicle with respect to a reference position in accordance with the running bearing detected by the bearing sensor and the running distance detected by the distance sensor;

a map storing means for storing road data indicative of a road map;

a map range selecting means for selecting the road data within a range of the vicinity of the present position estimated by said present position estimating means from said map storing means, and estimating an error amount of the road data within the range of the vicinity of said present position so as to select road data having a small error amount from among the road data within the selected range, and selectively utilizing said selected road data having a small error amount as a map evaluation range for use in a map match computing operation;

a map match computing means for effecting the map match computing operation so as to correct the present position on the road map with the use of the present position computed by the present position estimating means and the evaluation range selected by the map range selecting means;

an outputting means for outputting the present position of the vehicle corrected by the map computing means.

2. A vehicle position detecting apparatus comprising:

a bearing sensor for detecting an advancing bearing of a vehicle;

a distance sensor for detecting the running distance of the vehicle;

a present position estimating means for estimating a present position of the vehicle in accordance with an output of the distance sensor and an output of the bearing sensor;

a map storing means for storing road data indicative of a road network;

a map match computing means for conforming the present position estimating means to a point on the road network stored by the map storing means;

a temporary position computing means for determining temporary positions in the forward and in the rearward of the present position on the present road identical to that of the present position in accordance with the present position matched by the map match computing means when a curved road draws near in the forward of the vehicle;

an outputting means for outputting the present position matched by the map match computing means;

wherein the temporary position is computed by the temporary position computing means when the vehicle is approaching a curve, and wherein the map match computing means selects a most suitable one as the present position from among points recognized as a temporary position and the present position by the comparison with the output of the bearing sensor so as to match the present position.

3. A match position detecting apparatus comprising:

a bearing computing means for computing an advancing bearing of a vehicle;

a distance computing means for computing a moving distance of a vehicle;

a map storing means for storing map data indicative of a road map;

a present position estimating means for estimating a position of a vehicle in accordance with an output of the bearing computing means and an output of the distance computing means and the map data of the map storing means;

an outputting means for outputting a vehicle position obtained by the present position estimating means;

an absolute position computing means for computing the latitude and longitude of the vehicle position;

a position detecting means for obtaining a possible existence range of the vehicle with the absolute position computed by the absolute position computing means being a reference, examining the estimating position obtained by the present position estimating means and the including relation of the possible existence range;

a distance constant correcting means for computing a distance computing error from the estimating position and the possible existence range at the terminal, correcting the distance conversion constant of the distance computing means output from the distance calibrating section length and the distance computing error, the estimating position being included in the possible existence range at a starting point of at least the distance calibrating section, and being not included at a terminal point by the position detecting means.

4. A vehicle position detecting apparatus as defined in claim 3, further comprising a road length computing means for obtaining the moving distance of the vehicle as an integration value of the length of the road using the map data of the map storing means, wherein the distance constant correcting means corrects a distance conversion constant of the distance computing means output using the road length obtained by the road length computing means.

5. A vehicle position detecting apparatus as defined in claim 3, wherein the absolute position computing means is used as a global positioning system and is provided with a satellite combination judging means for judging a combination of satellites used for computation of the absolute position by the absolute position computing means, and a straight advance judging means for judging a straight advance of the vehicle, and wherein the distance constant correcting means is constant in the satellite combination judged by the satellite combination judging means, corrects the distance between the absolute positions of the vehicle obtained by the absolute position computing means and the distance conversion constant from the output integration value of the distance computing means when the combination of the satellites is constant by the satellite combination combining means and the vehicle is judged to be in a straight advance condition by the straight advance judging means.