Vehicular control object determination system and vehicular travel locus estimation system

• US 7,974,778 B2
• Filed: 09/16/2005
• Issued: 07/05/2011
• Est. Priority Date: 09/17/2004
• Status: Expired due to Fees

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Sato, Hiroshi, Inoue, Shigeru, Sawamoto, Kiichiro
• Primary Examiner(s): Keith; Jack W
• Assistant Examiner(s): Dager; Jonathan M
• Application Number:
  US11/229,364
• Publication Number:
  US 20060149462A1
• Time in Patent Office: 2,118 Days
• Field of Search: 701/301, 701/302
• US Class Current: 701/207
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 2520/06 Direction of travel
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2520/14 Yaw
• CPC Class Codes: B60W 2540/18 Steering angle
• CPC Class Codes: B60W 2554/00 Input parameters relating to objects
• CPC Class Codes: B60W 2554/80 Spatial relation or speed relative to objects
• CPC Class Codes: B60W 30/16 Control of distance between vehicles, e.g. keeping a distance to preceding vehicle
• CPC Class Codes: B60W 40/02 related to ambient conditions
• CPC Class Codes: G08G 1/16 Anti-collision systems road vehicle drive control systems for predicting or avoiding probable or impending collision otherwise than by control of a particular sub-unit B60W30/08

Abstract

In a vehicular control object determination system, locus correlation degree calculator calculates a degree of correlation between a future travel locus of a vehicle estimated by first travel locus estimator based on a vehicle speed and a yaw rate and a future travel locus of the vehicle estimated by second travel locus estimator based on a past travel locus of the vehicle calculated by travel locus calculator. When control object determiner determines a control object based on the travel locus estimated by the first travel locus estimator and predetermined control object determination conditions, the control object determination conditions are modified according to the degree of correlation, that is, the degree of reliability of the travel locus estimated by the first travel locus estimator, thereby achieving both accuracy with which the control object is determined and determination of the control object at a distance.

Claims

1. A vehicular travel locus estimation system comprising:

an object detector detecting a plurality of objects that are present in a direction of travel of a vehicle;

a vehicle speed sensor configured to detect a vehicle speed;

a yaw rate sensor configured to detect a yaw rate;

a first travel locus estimator operatively coupled to the vehicle speed sensor and the yaw rate sensor, the first travel locus estimator estimating a first future travel locus of the vehicle based on at least the vehicle speed detected by the vehicle speed sensor and the yaw rate detected by the yaw rate sensor;

a travel locus calculator calculating a past travel locus of the vehicle;

a second travel locus estimator estimating a second future travel locus of the vehicle based on the calculated past travel locus;

a control object determiner determining a control object;

a stationary state determiner determining whether the vehicle is in a substantially stationary state; and

an estimated travel locus output providing the first future travel locus estimated by the first travel locus estimator to the control object determiner when the stationary state determiner determines that the vehicle is not in a substantially stationary state and providing the second future travel locus estimated by the second travel locus estimator instead of the first future travel locus estimated by the first travel locus estimator to the control object determiner when the stationary state determiner determines that the vehicle is in a substantially stationary state;

wherein the control object determiner is configured to determine the control object from the plurality of objects based on the first future travel locus if the vehicle is not in a substantially stationary state and on the second future travel locus if the vehicle is in a substantially stationary state.

2. The vehicular travel locus estimation system according to claim 1, wherein the travel locus calculator has an absolute coordinate system that enables a subject vehicle position and a subject vehicle direction of the vehicle to be recorded in a memory device with a given point as a reference, calculates a subject vehicle direction in the absolute coordinate system based on the yaw rate detected by the yaw rate sensor, calculates a plurality of subject vehicle positions based on the calculated subject vehicle direction and the vehicle speed detected by the vehicle speed sensor, and calculates the past travel locus of the vehicle from the plurality of calculated subject vehicle positions in the absolute coordinate system.

3. The vehicular travel locus estimation system according to either claim 1, wherein the system further comprises a steering angle sensor detecting a steering angle of the vehicle, and wherein the travel locus calculator has an absolute coordinate system that enables a subject vehicle position and a subject vehicle direction of the vehicle to be recorded in a memory device with a given point as a reference, calculates a subject vehicle direction in the absolute coordinate system based on the steering angle detected by the steering angle sensor, calculates a plurality of subject vehicle positions based on the calculated subject vehicle direction and the vehicle speed detected by the vehicle speed sensor, and calculates the past travel locus of the vehicle from the plurality of calculated subject vehicle positions in the absolute coordinate system.

4. The vehicular travel locus estimation system according to claim 1, wherein the system further comprises subject vehicle position detector detecting a subject vehicle position in an absolute coordinate system based on a signal from outside the vehicle, and subject vehicle position memory storing the detected subject vehicle position, and wherein the travel locus calculator calculates the past travel locus of the vehicle from a plurality of subject vehicle positions stored by the subject vehicle position memory.

5. The vehicular travel locus estimation system according to claim 2, wherein the travel locus calculator calculates the past travel locus of the vehicle by subjecting the plurality of subject vehicle positions in the absolute coordinate system to a least-squares procedure.

6. The vehicular travel locus estimation system according to claim 3, wherein the travel locus calculator calculates the past travel locus of the vehicle by subjecting the plurality of subject vehicle positions in the absolute coordinate system to a least-squares procedure.

7. The vehicular travel locus estimation system according to claim 4, wherein the travel locus calculator calculates the past travel locus of the vehicle by subjecting the plurality of subject vehicle positions in the absolute coordinate system to a least squares procedure.