MONITORING APPARATUS AND METHOD

• US 20120253549A1
• Filed: 03/29/2012
• Published: 10/04/2012
• Est. Priority Date: 03/29/2011
• Status: Active Grant

• Current Assignee: Jaguar Land Rover Limited (TATA Motors Limited)
• Original Assignee: Jaguar Cars Limited (TATA Motors Limited)
• Inventors: Cund, Mark, Widdowson, Paul, Dunoyer, Alain, Breugelmans, Adrie
• Granted Patent: US 8,781,706 B2
• Time in Patent Office: Days
• US Class Current: 701/1
• CPC Class Codes: G01S 13/584 adapted for simultaneous range and velocity measurements
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 2013/93185 Controlling the brakes
• CPC Class Codes: G01S 2013/932 using own vehicle data, e.g. ground speed, steering wheel direction
• CPC Class Codes: G01S 2013/9324 Alternative operation using ultrasonic waves
• CPC Class Codes: G01S 7/4026 Antenna boresight
• CPC Class Codes: G01S 7/403 in azimuth, i.e. in the horizontal plane
• CPC Class Codes: G01S 7/4091 during normal radar operation

Abstract

An apparatus for monitoring one or more target objects in an environment external to a host vehicle by means of at least one sensor, the apparatus being arranged to trigger at least one action responsive to the detection of prescribed relative movement between the host vehicle and the one or more target objects. The apparatus is arranged to determine whether the at least one sensor is correctly aligned with respect to the host vehicle whereby, when the apparatus commences monitoring of the environment, the apparatus is arranged not to trigger the at least one action until the apparatus has determined that the at least one sensor is correctly aligned.

Claims

1. An apparatus for monitoring one or more target objects in an environment external to a host vehicle by means of at least one sensor, the apparatus being arranged to trigger at least one action responsive to the detection of prescribed relative movement between the host vehicle and the one or more target objects,

wherein the apparatus is arranged to determine whether the at least one sensor is correctly aligned with respect to the host vehicle whereby when the apparatus commences monitoring of the environment the apparatus is arranged not to trigger the at least one action until the apparatus has determined that the at least one sensor is correctly aligned.

2. Apparatus as claimed in claim 1 arranged to trigger the at least one action responsive to the detection of prescribed relative movement between the host vehicle and the one or more target objects in dependence on the speed of the host vehicle.

3. An apparatus as claimed in claim 1 operable to determine whether the at least one sensor is correctly aligned responsive to measurement of relative movement between the vehicle and at least one stationary target object.

4. An apparatus as claimed in claim 1 operable repeatedly to determine whether the at least one sensor is correctly aligned responsive to measurement of the relative movement between the vehicle and at least one target object.

5. An apparatus as claimed in claim 1 arranged to allow triggering of the at least one action when the apparatus has determined that the at least one sensor is correctly aligned by performing a measurement of alignment at a prescribed number of successive moments in time, or to allow triggering of the at least one action when the apparatus has determined that the at least one sensor is correctly aligned after each of a prescribed number of successive measurements of alignment.

6. An apparatus as claimed in claim 5 wherein each successive measurement of alignment is made with respect to a target object that is different from the target object with respect to which the preceding measurement of alignment was made.

7. An apparatus as claimed in claim 1 arranged to store a value of a reference angle parameter indicative of a reference angle of misalignment of the at least one sensor, the apparatus being arranged to determine whether the at least one sensor is correctly aligned by comparing a measured value of misalignment angle with the reference angle.

8. An apparatus as claimed in claim 7 configured to set a confidence parameter being a parameter indicative of a level of confidence that the at least one sensor is correctly aligned to a first value when the apparatus commences monitoring of the environment, the first value indicating that confidence is low, and subsequently to increment the value of the first parameter by a prescribed increment value each time it is determined that a difference between the measured angle of misalignment and the reference angle of misalignment is less than or equal to a prescribed tolerance angle.

9. An apparatus as claimed in claim 8 configured to decrement the confidence parameter by a prescribed decrement value each time it is determined that a difference between the measured angle of misalignment and the reference angle is greater than the prescribed tolerance angle, optionally wherein the decrement value is greater than the increment value.

10. An apparatus as claimed in claim 8 configured to set the confidence parameter to the first value if the reference angle exceeds a prescribed maximum reference angle value.

11. An apparatus as claimed in claim 8 arranged to allow triggering of the at least one action only if the value of the confidence parameter exceeds a prescribed second value.

12. An apparatus as claimed in claim 7 wherein the reference angle parameter is an average value of the measured value of misalignment angle over a prescribed number of measurements of misalignment angle.

13. An apparatus as claimed in claim 1 comprising or in combination with range determination means operable to determine the range of the target object from the host vehicle and the rate of change of the range.

14. An apparatus as claimed in claim 13 wherein the range determination means comprises either a radar transmitter and a radar receiver or an ultrasonic transmitter and an ultrasonic receiver, the apparatus being arranged to determine the range of the target object from the vehicle by means of a signal transmitted from the transmitter and received at the receiver following reflection by the target object.

15. A host vehicle comprising an apparatus as claimed in claim 1.

16. A host vehicle comprising an apparatus for monitoring one or more target objects in an environment external to the vehicle by means of at least one sensor, the apparatus being arranged to trigger at least one action responsive to the detection of prescribed relative movement between the host vehicle and the one or more target objects,

wherein the apparatus is arranged to determine whether the at least one sensor is correctly aligned with respect to the host vehicle whereby when the apparatus commences monitoring of the environment the apparatus is arranged not to trigger the at least one action until the apparatus has determined that the at least one sensor is correctly aligned,

the apparatus comprising range determination means operable to determine the range of the target object from the host vehicle and the rate of change of the range, the range determination means comprising either a radar transmitter and a radar receiver or an ultrasonic transmitter and an ultrasonic receiver, the apparatus being arranged to determine the range of the target object from the vehicle by means of a signal transmitted from the transmitter and received at the receiver following reflection by the target object.

17. A method of monitoring one or more target objects in an environment external to a host vehicle by means of at least one sensor,

the method comprising detecting a position of the one or more target objects with respect to the vehicle and triggering at least one action responsive to the detection of prescribed relative movement between the host vehicle and the one or more target objects,

the method further comprising determining whether the at least one sensor is correctly aligned with respect to the vehicle,

whereby when the monitoring apparatus commences monitoring of the environment the method comprises not triggering the at least one action until the apparatus has determined that the at least one sensor is correctly aligned.