Road shape predicting method and vehicle controlling method

• US 6,230,083 B1
• Filed: 07/12/1999
• Issued: 05/08/2001
• Est. Priority Date: 07/10/1998
• Status: Expired due to Term

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Matsuda, Shohei, Otabe, Makoto, Sakaki, Yuji
• Primary Examiner(s): Nguyen, Tan
• Assistant Examiner(s): Tran, Dalena
• Application Number:
  US09/351,297
• Time in Patent Office: 666 Days
• Field of Search: 701/1, 701/201, 701/205, 701/209, 701/210, 701/207, 701/225, 701/208, 340/995
• US Class Current: 701/1
• CPC Class Codes: G01C 21/26 specially adapted for navigation in a road network

Abstract

A road shape predicting method includes the steps of: selecting three positions of positions of a plurality of nodes constituting road map data and an own vehicle position on a road; and predicting the road shape on the basis of a crossing angle formed by a link connecting a first position and a second position of the selected three positions and another link connecting the second and a third position thereof, and a link length between the second and the third positions. In case that the link length between the second and the third positions is not larger than a reference link length set in accordance with the crossing angle, the third position is excluded, and the position of a node further forward is adopted in place of the third position, to thereby predict the road shape.

Claims

1. A road shape predicting method, comprising the steps of:

selecting three positions of positions of a plurality of nodes constituting road map data and an own vehicle position on a road; and

predicting the road shape on the basis of a crossing angle formed by a link connecting a first position and a second position of the selected three positions and another link connecting the second and a third position thereof, and a link length between the second and the third positions,

wherein, in case that the link length between the second and the third positions is not larger than a reference link length set in accordance with the crossing angle, the third position is excluded, and the position of a node further forward is adopted in place of the third position, to thereby predict the road shape.

2. A road shape predicting method according to claim 1, wherein said link length L_ref is given by

3. A road shape predicting method according to claim 1, wherein when the link length between the position of the node further forward and the second position exceeds a prescribed length, the adoption of the position of the node further forward is avoided.

4. A road shape predicting method according to claim 3, wherein said prescribed length L_max is given by

5. A road shape predicting method according to claim 1, wherein the positions of the plurality of nodes are decided so that a sag being a distance between the link connecting the adjacent nodes and the actual road is not more than a preset upper limit thereof.

6. A vehicle controlling method using a road shape predicting method defined in claim 1, wherein the running state of a vehicle is controlled on the basis of said predicted road shape so that the vehicle can pass a forward road.