Driving assist system for vehicle

• US 20040172185A1
• Filed: 11/19/2003
• Published: 09/02/2004
• Est. Priority Date: 11/27/2002
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Boer, Erwin R., Yamamura, Tomohiro
• Granted Patent: US 7,200,481 B2
• Time in Patent Office: Days
• US Class Current: 701/96
• CPC Class Codes: B60G 2800/704 predicting unorthodox driving conditions for safe or optimal driving
• CPC Class Codes: B60K 26/021 with means for providing feel, e.g. by changing pedal force characteristics
• CPC Class Codes: B60W 2050/143 Alarm means
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2520/105 Longitudinal acceleration
• CPC Class Codes: B60W 2554/00 Input parameters relating to objects
• CPC Class Codes: B60W 2554/4042 Longitudinal speed
• CPC Class Codes: B60W 2554/801 Lateral distance
• CPC Class Codes: B60W 2554/804 Relative longitudinal speed
• CPC Class Codes: B60W 30/08 Active safety systems predicting or avoiding probable or impending collision or attempting to minimise its consequences
• CPC Class Codes: B60W 30/095 Predicting travel path or likelihood of collision
• 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: B60W 40/09 Driving style or behaviour
• CPC Class Codes: B60W 50/0097 Predicting future conditions
• CPC Class Codes: B60W 50/16 Tactile feedback to the driver, e.g. vibration or force feedback to the driver on the steering wheel or the accelerator pedal
• CPC Class Codes: G08G 1/166 for active traffic, e.g. moving vehicles, pedestrians, bikes

Abstract

A vehicle driving assist system of the present invention detects a vehicle condition and a traveling environment of a subject vehicle; and calculates an extent of influence on the subject vehicle due to future changes in surrounding environment. The vehicle driving assist system then calculates the risk potential around the subject vehicle based on the extent of influence. Operation reaction force of an accelerator pedal is controlled according to the risk potential thus calculated.

Claims

1. A driving assist system for a vehicle, comprising:

a state recognition device that detects a vehicle condition and a traveling environment of a subject vehicle;

a future state prediction device that calculates a current degree of proximity to a preceding vehicle and/or an extent of influence on the subject vehicle due to future changes in surrounding environment to predict future driving conditions, based on detection results of the state recognition device; and

a risk potential calculating device that calculates risk potential around the subject vehicle based on the future driving conditions predicted by the future state prediction device and a driver'"'"'s intentions.

2. A driving assist system for a vehicle according to claim 1, further comprising:

a reaction force calculating device that calculates an operation reaction force to be generated in a vehicle operating unit according to the risk potential calculated by the risk potential calculating device; and

a reaction force generating device that generates the operation reaction force calculated by the reaction force calculating device in the vehicle operating unit.

3. A driving assist system for a vehicle according to claim 2, wherein:

the vehicle operating unit is an accelerator pedal;

the reaction force calculating device calculates the operation reaction force to be generated in the accelerator pedal; and

the reaction force generating device generates the operation reaction force in the accelerator pedal.

4. A driving assist system for a vehicle according to claim 1, further comprising:

a warning system that outputs a warning according to the risk potential calculated by the risk potential calculating device.

5. A driving assist system for a vehicle according to claim 1, wherein:

the risk potential calculating device estimates the driver'"'"'s intentions from acceleration and deceleration of the subject vehicle to calculate the risk potential.

6. A driving assist system for a vehicle according to claim 1, wherein:

the risk potential calculating device estimates the driver'"'"'s intentions from acceleration and deceleration of the subject vehicle and the preceding vehicle to calculate the risk potential.

7. A driving assist system for a vehicle according to claim 1, wherein:

the state recognition device detects the vehicle condition and the traveling environment of the subject vehicle including a subject vehicle speed, a preceding vehicle speed, and a distance between the subject vehicle and the preceding vehicle;

the future state prediction device calculates a time headway based on one of a set of the distance between vehicles and the subject vehicle speed and a set of the distance between vehicles and the preceding vehicle speed as the extent of influence due to changes in the surrounding environment; and

the risk potential calculating device calculates the risk potential based on a reciprocal of the time headway.

8. A driving assist system for a vehicle according to claim 7, wherein:

the risk potential calculating device calculates the risk potential based on a linear sum of the reciprocal of the time headway and a time differentiated value of the reciprocal of the time headway.

9. A driving assist system for a vehicle according to claim 7, wherein:

the risk potential calculating device calculates based on a linear sum of the reciprocal of the time headway, a time differentiated value of the reciprocal of the time headway, and a twice differentiated value of the reciprocal of the time headway.

10. A driving assist system for a vehicle according to claim 1, wherein:

the state recognition device detects the vehicle condition and the traveling environment of the subject vehicle including a subject vehicle speed, a preceding vehicle speed, and a distance between the subject vehicle and the preceding vehicle;

the future state prediction device calculates time to contact based on a relative speed and the distance between vehicles detected by the state recognition device as the degree of proximity to the preceding vehicle; and

the risk potential calculating device calculates the risk potential based on a reciprocal of the time to contact.

11. A driving assist system for a vehicle according to claim 10, wherein:

the risk potential calculating device calculates the risk potential based on a linear sum of the reciprocal of the time to contact, and a time integrated value of the reciprocal of the time to contact.

12. A driving assist system for a vehicle according to claim 10, wherein:

the risk potential calculating device calculates the risk potential based on a linear sum of the reciprocal of the time to contact, a time integrated value of the reciprocal of the time to contact, and a time differentiated value of the reciprocal of the time to contact.

13. A driving assist system for a vehicle, comprising:

a state recognition means for detecting a vehicle condition and a traveling environment of a subject vehicle;

a future state prediction means for calculating a current degree of proximity to a preceding vehicle and/or an extent of influence on the subject vehicle due to future changes in surrounding environment to predict future driving conditions, based on detection results of the state recognition means; and

a risk potential calculating means for calculating risk potential around the subject vehicle based on the future driving conditions predicted by the future state prediction means and a driver'"'"'s intentions.

14. A vehicle, comprising:

a vehicle operating unit;

a state recognition device that detects a vehicle condition and a traveling environment of a subject vehicle;

a future state prediction device that calculates a current degree of proximity to a preceding vehicle and/or an extent of influence on the subject vehicle due to future changes in surrounding environment to predict future driving conditions, based on detection results of the state recognition device;

a risk potential calculating device that calculates risk potential around the subject vehicle based on the future driving conditions predicted by the future state prediction device and a driver'"'"'s intentions;

a reaction force calculating device that calculates an operation reaction force to be generated in the vehicle operating unit according to the risk potential calculated by the risk potential calculating device; and

a reaction force generating device that generates the operation reaction force calculated by the reaction force calculating device in the vehicle operating unit.

15. A method for calculating risk potential, comprising:

detecting a vehicle condition and a traveling environment of a subject vehicle;

predicting future driving conditions by calculating a current degree of proximity to a preceding vehicle and/or an extent of influence on the subject vehicle due to future changes in surrounding environment based on the vehicle conditions and the traveling environment having been detected; and

calculating the risk potential around the subject vehicle based on the predicted future driving conditions and a driver'"'"'s intentions.

16. A method for calculating risk potential according to claim 15, wherein:

a time headway is calculated based on one of a set of a distance between the subject vehicle and the preceding vehicle and a subject vehicle speed and a set of the distance between vehicles and a preceding vehicle speed as the extent of influence due to changes in the surrounding environment; and

the risk potential is calculated based on a linear sum of a reciprocal of the time headway and a time differentiated value of the reciprocal of the time headway.

17. A method for calculating risk potential according to claim 15, wherein:

a time headway is calculated based on one of a set of a distance between the subject vehicle and the preceding vehicle and a subject vehicle speed and a set of the distance between vehicles and a preceding vehicle speed as the extent of influence due to changes in the surrounding environment; and

the risk potential is calculated based on a linear sum of a reciprocal of the time headway, a time differentiated value of the reciprocal of the time headway, and a twice differentiated value of the reciprocal of the time headway.

18. A method for calculating risk potential according to claim 15, wherein:

time to contact is calculated based on a relative speed and a distance between the subject vehicle and the preceding vehicle as the degree of proximity to the preceding vehicle; and

the risk potential is calculated based on a linear sum of a reciprocal of the time to contact and a time integrated value of the reciprocal of the time to contact.

19. A method for calculating risk potential according to claim 15, wherein:

time to contact is calculated based on a relative speed and a distance between the subject vehicle and the preceding vehicle as the degree of proximity to the preceding vehicle; and

the risk potential is calculated based on a linear sum of a reciprocal of the time to contact, a time integrated value of the reciprocal of the time to contact, and a time differentiated value of the reciprocal of the time to contact.