Method and apparatus for determining a target vehicle position from a source vehicle using a radar

• US 6,628,227 B1
• Filed: 07/23/2002
• Issued: 09/30/2003
• Est. Priority Date: 07/23/2002
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Smirnov, Nikolay V., Prakah-Asante, Kwaku O., Rao, Manoharprasad K., Strumolo, Gary Steven
• Primary Examiner(s): Tarcza, Thomas H.
• Assistant Examiner(s): ANDREA, BRIAN K
• Application Number:
  US10/201,670
• Time in Patent Office: 434 Days
• Field of Search: 342/70, 180/167, 180/169, 340/435, 340/436, 340/438, 701/301, 701/223, 701/96
• US Class Current: 342/70
• CPC Class Codes: G01S 13/505 using Doppler effect for determining closest range to a target or corresponding time, e.g. miss-distance indicator
• CPC Class Codes: G01S 13/582 adapted for simultaneous range and velocity measurements
• CPC Class Codes: G01S 13/589 measuring the velocity vector
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 15/876 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S15/872 takes precedence
• CPC Class Codes: G01S 2013/932 using own vehicle data, e.g. ground speed, steering wheel direction
• CPC Class Codes: G01S 2013/93271 in the front of the vehicles

Abstract

A sensing system (10) for an automotive vehicle includes a first radar sensor (18) generating a first and a second range signal, and a second radar sensor (20) generating a first and a second range signal corresponding to two sampling time periods. A controller (12) is coupled to the first radar sensor (18) and the second radar sensor (20). The controller (12) calculates a first position and a second position from the first radar sensor and the second radar sensor range measurements. The controller (12) generates a first set of points corresponding to the first position and a second set of points corresponding to the second position. The controller (12) calculates a plurality of calculated range-rate values in response to the first set of points and the second set of points. The controller (12) compares the plurality of calculated range-rate values to the measured range-rate and selects the closest range-rate from the plurality of calculated range-rate values. A couple of target position points is generated from the first set of points and the second set of points corresponding to the calculated closest range-rate.

Claims

1. A sensing system for an automotive vehicle comprising:

a first radar sensor generating a first range and a second range signal;

a second radar sensor generating a first range and a second range signal;

said first or second radar sensor generating a measured range-rate; and

a controller coupled to said first radar sensor and said second radar sensor, said controller calculating a first position and a second position from the first radar sensor and the second radar sensor range measurements, generating a first set of points corresponding to the first position, generating a second set of points corresponding to the second position, calculating a plurality of calculated range-rate values in response to the first set of points and the second set of points, comparing the plurality of calculated range- values to the measured range-rate, selecting a closest range-rate from the plurality of calculated range-rate values and generating a couple of target position points from the first set of points and the second set of points corresponding to the closest range-rate to the measured range-rate.

2. A system as recited in claim 1 wherein said controller generates a target object trajectory from the couple of selected target position points.

3. A system as recited in claim 1 further comprising a countermeasure, said controller controlling a countermeasure in response to the target object trajectory.

4. A system as recited in claim 1 further comprising a vehicle speed sensor generating a source vehicle speed signal corresponding to the longitudinal speed of the vehicle;

wherein said controller activates said countermeasures in response to the source vehicle speed signal.

5. A method of determining the position of a target vehicle comprising:

determining a first range and a second range from a first radar sensor;

determining a first range and a second range from a second radar sensor;

calculating a first position and a second position from the first range and second range measurements;

evaluating a measured range-rate;

generating a first set of points corresponding to the first position;

generating a second set of points corresponding to the second position;

calculating a plurality of calculated range-rate values in response to the first set of points and the second set of points;

comparing the plurality of calculated range-rate values to the measured range-rate;

selecting the closest range-rate to the measured range-rate from the plurality of range-rate values; and

generating a couple of target object position points from the first set of points and the second set of points corresponding to the closest range-rate to the measured range-rate.

6. A method as recited in claim 5 further comprising generating a trajectory from the couple target object position points.

7. A method as recited in claim 5 further comprising generating a target velocity from the couple of target object position points.

8. A method as recited in claim 5 wherein calculating comprises calculating a plurality of calculated range-rate values for each of the first set of points with each point of the second set of points.

9. A method of operating a countermeasure system comprising:

determining a first range and a second range from a first radar sensor;

determining a first range and a second range from a second radar sensor;

calculating a first position and a second position from the first range and second range measurements;

evaluating a measured range-rate;

generating a first set of points corresponding to the first position;

generating a second set of points corresponding to the second position;

calculating a plurality of calculated range-rate values in response to the first set of points and the second set of points;

comparing the plurality of calculated range values to the measured range-rate;

selecting the closest range-rate from the plurality of range-rate values; and

generating a couple of target object position points from the first set of points and the second set of points corresponding to the closest calculated range-rate to the measured range-rate.

10. A method as recited in claim 9 further comprising generating a trajectory from the couple of target object position points.

11. A method as recited in claim 9 further comprising controlling a countermeasure in response to the target object trajectory.

12. A method as recited in claim 9 further comprising generating a target object velocity from the couple of target object position points.

13. A method as recited in claim 9 further comprising controlling the countermeasure in response to the target velocity.

14. A method as recited in claim 9 further comprising generating a target object acceleration.

15. A method as recited in claim 9 further comprising controlling the countermeasure in response to the target acceleration.

16. A system as recited in claim 9 further comprising generating a source vehicle speed signal corresponding to the longitudinal speed of the vehicle;

and activating a countermeasure in response to the source vehicle speed signal.

17. A method as recited in claim 16 wherein activating a countermeasure comprises activating at least one of pre-arming airbags, pretensioning motorized belt pretensioners, activating and adjusting the host vehicle suspension height in response to the target object trajectory.