Vehicle maneuvering control device

• US 6,208,927 B1
• Filed: 09/09/1998
• Issued: 03/27/2001
• Est. Priority Date: 09/10/1997
• Status: Expired due to Term

• Current Assignee: Subaru Corp.
• Original Assignee: Fuji Heavy Industries Limited (Subaru Corp.)
• Inventors: Matsuno, Koji, Mine, Atsushi
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): MARC-COLEMAN, MARTHE Y
• Application Number:
  US09/150,194
• Time in Patent Office: 930 Days
• Field of Search: 701/70, 701/72, 701/75, 701/79, 701/23, 701/25, 701/96, 701/97, 701/80
• US Class Current: 701/70
• CPC Class Codes: B60K 31/0058 responsive to externally generated signalling
• CPC Class Codes: B60K 31/0083 responsive to centrifugal force acting on vehicle due to the path it is following
• CPC Class Codes: B60W 2520/125 Lateral acceleration
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2552/20 Road profile, i.e. the change in elevation or curvature of a plurality of continuous road segments
• CPC Class Codes: B60W 2552/30 Road curve radius
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 30/18145 Cornering

Abstract

A vehicle maneuvering control device is disclosed. A curve of a road is detected to calculate curve data including a distance between a vehicle and the curve, and a physical quantity indicating a degree of the curve. An allowable deceleration is set at which the vehicle can travel in accordance with conditions of the road. An allowable lateral acceleration is set at which the vehicle can travel in accordance with the conditions of the road. An allowable approaching speed is set at which the vehicle can approaches the curve based on the physical quantity and the lateral acceleration. A deceleration judging speed is calculated for judging whether a present speed at which the vehicle is traveling should be decreased based on the distance, the allowable deceleration and the allowable approaching speed. And, the present speed is decreased when it is higher than the deceleration judging speed.

Claims

1. A control device for maneuvering a vehicle having a navigation system mounted on said vehicle for deriving positional information thereof and for outputting a positional signal, a pair of camera mounted on said vehicle for detecting road conditions in front of said vehicle and for delivering a road width signal, a vehicle speed sensor mounted on said vehicle for detecting a vehicle speed and for producing a vehicle speed signal, a yaw rate sensor for sensing a yaw rate of said vehicle and for outputting a yaw rate signal, a longitudinal acceleration sensor for detecting an acceleration amount in a running direction of said vehicle and for outputting a longitudinal acceleration signal, a warning device mounted on said vehicle for generating a warning signal to a driver when said vehicle is going into a dangerous running condition, said control device comprising:

vehicle speed changing rate calculating means responsive to said vehicle speed signal for deriving a changing rate of said vehicle speed and for producing a vehicle speed changing rate signal;

road surface coefficient estimating means responsive to said yaw rate signal for predicting a road surface coefficient and for outputting a road surface coefficient signal;

curving condition deciding means responsive to said positional signal and said road width signal for deriving positional data of a curving point where said vehicle is negotiating and for producing a curving condition signal;

road inclination estimating means responsive to said longitudinal acceleration signal for calculating an inclination rate of a road where said vehicle is running and for outputting a road inclination signal;

allowable deceleration setting means responsive to said road surface coefficient signal and said road inclination signal for deciding an optimum deceleration rate so as to safely pass along said road and for generating an allowable deceleration rate signal;

allowable lateral acceleration setting means responsive to said road surface coefficient signal, said vehicle speed signal, said curving condition signal and said road inclination signal for deciding a lateral acceleration rate so as to safely pass along said road and for generating an allowable lateral acceleration rate signal;

allowable approaching speed setting means responsive to said curving condition and said allowable lateral acceleration rate signal for deciding an allowable approaching speed into said road on a basis of a curvature radius of said road and for producing an allowable approaching speed signal;

warning speed calculating means responsive to said allowable deceleration rate signal and said allowable approaching speed signal for calculating a warning speed based upon a distance between said vehicle and said road and for generating a warning speed signal;

deceleration rate calculating means responsive to said allowable deceleration rate signal and said allowable approaching speed signal for calculating a deceleration rate so as to perform an optimum control to safely and reliably pass said road by sufficiently taking into consideration of said distance; and

deceleration means for decelerating said vehicle speed based on said deceleration rate.

2. The control device according to claim 1, wherein:

said allowable lateral acceleration setting means further includes means for adjusting said lateral acceleration rate based on said vehicle speed.

3. The control device according to claim 1, wherein:

said allowable lateral acceleration setting means further includes means for adjusting said lateral acceleration rate based on an angle of curve.

4. The control device according to claim 1, wherein:

said allowable lateral acceleration setting means further includes means for adjusting said lateral acceleration rate based on a direction in which said vehicle turns.

5. A control device for maneuvering a vehicle, comprising:

vehicle running condition detecting means for detecting a vehicle running condition including a vehicle running speed;

a navigation system for detecting a current vehicle position and for storing road map data including node data representing a position of a road;

curve detection means for detecting a curve of the road and calculating curve data including a distance between said current vehicle position and said curve, a radius of curvature and an angle of said curve based on said node data;

road surface friction coefficient estimating means for estimating road surface friction coefficient based on said vehicle running condition;

allowable deceleration calculating means for calculating an allowable deceleration which said vehicle can decelerate based on said friction coefficient;

allowable lateral acceleration calculating means for calculating an allowable lateral acceleration by which said vehicle can safely pass through said curve based on said friction coefficient;

allowable approaching speed calculating means for calculating an allowable approaching speed by which said vehicle can safely pass through said curve based on said radius and said allowable lateral acceleration;

warning judging speed calculating means for calculating a warning judging speed to judge whether a warning control for warning to a driver should be executed or not based on said distance, said allowable deceleration speed and said allowable approaching speed;

deceleration judging speed calculating means for calculating a deceleration judging speed to judge whether a deceleration control for decelerating said vehicle running speed should be executed based on said distance, said allowable deceleration speed and said allowable approaching speed; and

controlling means for warning the driver when said present vehicle speed is higher than said warning judging speed and for decreasing said vehicle speed when said vehicle speed is higher than said deceleration judging speed.

6. The control system according to claim 5, further comprising:

road slope degree calculating means for calculating road slope degree based on said vehicle running condition;

wherein said allowable deceleration speed calculating means corrects said allowable deceleration speed based on said road slope degree.

7. The control system according to claim 5, further comprising:

road slope degree calculating means for calculating road slope degree based on said vehicle running condition;

wherein said allowable lateral acceleration calculating means corrects said allowable lateral acceleration based on said road slope degree.

8. The control system according to claim 5, wherein:

said allowable lateral acceleration calculating means further includes means for correcting said allowable lateral acceleration based on said vehicle running speed.

9. The control system according to claim 5, wherein

said allowable lateral acceleration calculating means includes means for correcting said allowable lateral acceleration based on said angle of curve.

10. The control system according to claim 5, further comprising:

road slope degree calculating means for calculating road slope degree based on said vehicle running condition;

wherein said allowable lateral acceleration calculating means includes

road slope correcting means for correcting said allowable lateral acceleration based on said road slope degree;

vehicle running speed correcting means for correcting said allowable lateral acceleration based on said vehicle running speed; and

curve angle correcting means for correcting said allowable lateral acceleration based on said curve angle.

11. The control system according to claim 5, further comprising:

road configuration detecting means for obtaining road configuration data including road width through images of the road taken by the cameras,

wherein said curve detection means modifies the curve data based on said road configuration data.

12. The control system according to claim 5, further comprising:

change rate detecting means for detecting change rate of at least said friction coefficient of the road,

wherein when said change rate detected by said change rate detecting means is a lower than a predetermined value, previously calculated values of allowable deceleration, said allowable lateral acceleration and said allowable approaching speed are used to calculate said warning judging speed and said deceleration judging speed.

13. The control system according to claim 5, further comprising:

means for prohibiting said deceleration control and said warning control when a turning signal switch has been activated.

14. The control system according to claim 5, further comprising:

means for prohibiting said deceleration control and said warning control when said steeling angle is larger than a predetermined value.

15. The control system according to claim 5, further comprising:

data reduction means for reducing said curve data by selecting necessary curve data to calculate said allowable lateral acceleration, said allowable approaching speed, said warning judging speed and said deceleration judging speed based on a curve geometry, a curve direction and a distance between curves.

16. A control device for maneuvering a vehicle, comprising:

vehicle running condition detecting means for detecting vehicle running condition including a vehicle running speed;

navigation system for detecting a current vehicle position and for storing road map data including node data representing a position of road;

curve geometry detector for calculating curve data including a radius of curvature, curve direction and a distance between said curves based on said node data;

data reduction means for reducing said curve data by selecting necessary curve data based on said curvature, said curve direction and said distance between curves;

warning and decelerating control judging means for judging whether warning control for warning to driver should be executed and for judging whether decelerating control for decelerating said vehicle running speed should be executed based on said vehicle condition and said selected curve data; and

means for warning the driver based on output from said warning and decelerating judging means, and for decelerating said vehicle based on output from said warning and decelerating judging means.

17. The control system according to claim 16, wherein:

said reduction means determines said curve data as unnecessary curve data when the execution of said warning and decelerating control based on said curve data is absorbed by the execution of said warning and decelerating control based on the other curve data.