Method and system for vehicle impact assessment using driver braking estimation

• US 20040102901A1
• Filed: 11/26/2002
• Published: 05/27/2004
• Est. Priority Date: 11/26/2002
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (General Motors Company)
• Inventors: Altan, Osman D., Labuhn, Pamela I., Kiefer, Raymond J., Chundrlik, William J. Jr.
• Granted Patent: US 6,871,145 B2
• Time in Patent Office: Days
• US Class Current: 701/301
• CPC Class Codes: G08G 1/165 for passive traffic, e.g. including static obstacles, trees
• CPC Class Codes: G08G 1/166 for active traffic, e.g. moving vehicles, pedestrians, bikes

Abstract

A method for predicting an impact condition between a host vehicle and an object detected in a path of travel of the host vehicle includes receiving measured parameters from the host vehicle and the object, and receiving a system sensitivity input from a driver of the host vehicle. A braking response of the driver of the host vehicle is estimated, based on the received system sensitivity input, and a projected travel range profile for both the host vehicle and the object is determined, based upon the measured parameters and the estimated braking response. The impact condition is established whenever a comparison of the projected travel range profile for the host vehicle and for the object establishes an intersection therebetween.

Claims

1. A method for predicting an impact condition between a host vehicle and an object detected in a path of travel of the host vehicle, the method comprising:

receiving measured parameters from the host vehicle and the object;

receiving a system sensitivity input from a driver of the host vehicle;

estimating a braking response of the driver of the host vehicle, said estimated braking response based on said received system sensitivity input; and

determining a projected travel range profile for both the host vehicle and the object, based upon said measured parameters and said estimated braking response;

wherein, the impact condition is established whenever a comparison of said projected travel range profile for the host vehicle and for the object establishes an intersection therebetween.

2. The method of claim 1, wherein said projected travel range profile for the host vehicle is determined by calculating a deceleration value for the host vehicle, said calculated deceleration value being a function of said estimated braking response, and wherein said estimated braking response of the driver of the host vehicle is further based upon the host vehicle velocity and a closing speed of the object.

3. The method of claim 2, wherein said projected travel range profile for the object is determined by assigning a deceleration value for the object, said assigned deceleration value being based upon said velocity and said acceleration of the object.

4. The method of claim 3, wherein said assigned deceleration value for the object is set to a default value whenever the magnitude of the actual deceleration of the object is at or below said default value, and said assigned deceleration value for the object is set to the actual deceleration of the object whenever the magnitude of the actual deceleration of the object exceeds said default value.

5. The method of claim 4, wherein said default value is about −

0.2 g.

6. The method of claim 2, wherein if the object is determined to be stationary, and said projected travel range of the host vehicle yields a stopping distance less than the position of the object, then the impact condition is not established.

7. The method of claim 2, wherein if the object is determined to be stationary, and said projected travel range of the host vehicle yields a stopping distance equal to or greater than the position of the object, then the impact condition is established.

8. A method for generating a frontal impact warning for a driver of a host vehicle, the method comprising:

determining, during a given sample time period, actual velocity and acceleration data for both the host vehicle and for a lead vehicle detected in the path of travel of the host vehicle;

estimating a braking response of the driver of the host vehicle;

assigning a deceleration value for the lead vehicle;

generating a projected travel range for the host vehicle, based upon said actual velocity data for the host vehicle and the lead vehicle, and further based upon said estimated braking response of the driver of the host vehicle;

generating a projected travel range for the lead vehicle, based upon said actual velocity data for the lead vehicle and upon said assigned deceleration value for the lead vehicle; and

comparing said projected travel range for the host vehicle with said projected travel range for the lead vehicle and generating an alert signal to the host vehicle driver whenever an intersection of travel ranges therebetween is calculated.

9. The method of claim 8, wherein said estimated braking response of the driver of the host vehicle is based upon a system sensitivity input from the driver of the host vehicle, upon the velocity of the host vehicle, and a closing speed of the lead vehicle.

10. The method of claim 9, wherein said system sensitivity input is selected from a plurality of discrete settings corresponding to the reaction time of the host driver in performing a braking operation.

11. The method of claim 8, wherein said assigned deceleration value for the lead vehicle is set to a default value whenever the magnitude of the actual deceleration of the lead vehicle is at or below said default value, and said assigned deceleration value for the lead vehicle is set to the actual deceleration of the lead vehicle whenever the magnitude of the actual deceleration of the lead vehicle exceeds said default value.

12. The method of claim 11, wherein said default value is about −

0.2 g.

13. The method of claim 8, wherein if the lead vehicle is determined to be stationary, and said projected travel range of the host vehicle yields a stopping distance less than the position of the lead vehicle, then the alert signal is not generated.

14. The method of claim 8, wherein if the object is determined to be stationary, and said projected travel range of the host vehicle yields a stopping distance equal to or greater than the position of the object, then the impact condition is established.

15. The method of claim 8, further comprising:

determining, upon receiving said actual velocity and acceleration data for both the host and lead vehicles, whether any of a plurality of exit criteria are present during said current sample time period and, if so, then said projected travel ranges for the host and lead vehicles are not generated during said current sample time period.

16. The method of claim 15, wherein said exit criteria include at least one of:

a determination that the driver of the host vehicle is in the process of braking;

a determination that the lead vehicle is an oncoming vehicle;

a determination that the lead vehicle is opening or accelerating at a rate so as to increase its range from the host vehicle; and

a determination that the driver of the host vehicle is accelerating the host vehicle so as to overtake the lead vehicle.

17. A forward impact warning system, comprising:

an algorithm for assessing the likelihood of a frontal collision between a host vehicle and a lead vehicle detected in the path of travel of the host vehicle, said algorithm having actual velocity and acceleration data for the host vehicle and the lead vehicle as inputs thereto;

said algorithm further estimating a braking response of the driver of the host vehicle, and generating a projected travel range for the host vehicle, based upon said actual velocity data for the host vehicle and the lead vehicle, and further based upon said estimated braking response of the driver of the host vehicle;

said algorithm further assigning a deceleration value for the lead vehicle, and generating a projected travel range for the lead vehicle, based upon said actual velocity data for the lead vehicle and upon said assigned deceleration value for the lead vehicle; and

a warning alert mechanism, in communication with said algorithm, said warning alert mechanism generating an alert signal to the driver of the host vehicle whenever said algorithm identifies an intersection between said projected travel range for the host vehicle and said projected travel range for the lead vehicle.

18. The system of claim 17, wherein said algorithm further includes a system sensitivity input thereto, said system sensitivity input being selected from a plurality of discrete settings corresponding to the reaction time of the host driver in performing a braking operation.

19. The system of claim 18, wherein said estimated braking response of the driver of the host vehicle is based upon said system sensitivity input, and upon the velocity of the host vehicle and a closing speed of the lead vehicle.

20. The system of claim 17, wherein said assigned deceleration value for the lead vehicle is set to a default value whenever the magnitude of the actual deceleration of the lead vehicle is at or below said default value, and said assigned deceleration value for the lead vehicle is set to the actual deceleration of the lead vehicle whenever the magnitude of the actual deceleration of the lead vehicle exceeds said default value.

21. The system of claim 20, wherein said default value is about −

0.2 g.

22. A storage medium, comprising:

a machine readable computer code for predicting an impact condition between a host vehicle and an object detected in a path of travel of the host vehicle; and

instructions for causing a computer to implement a method, the method further comprising;

receiving measured parameters from the host vehicle and the object;

receiving a system sensitivity input from a driver of the host vehicle;

estimating a braking response of the driver of the host vehicle, said estimated braking response based on said received system sensitivity input; and

determining a projected travel range profile for both the host vehicle and the object, based upon said measured parameters and said estimated braking response;

wherein, the impact condition is established whenever a comparison of said projected travel range profile for the host vehicle and for the object establishes an intersection therebetween.