Sensor failure mitigation system and mode management

Patent metadata

Field	Value
Publication number	US-9533683-B2
Application number	US-201414562081-A
Country	US
Kind code	B2
Filing date	Dec 5, 2014
Priority date	Dec 5, 2014
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A trailer backup assist system includes a sensor that senses a hitch angle between a vehicle and a trailer. The trailer backup assist system also includes a steering input device that provides a backing path of the trailer. Further, the trailer backup assist system includes a controller that generates a steering command for the vehicle based on the hitch angle and the backing path. The controller generates a countermeasure for operating the vehicle when the sensor fails to sense the hitch angle.

First claim

The invention claimed is:

1. A trailer backup assist system, comprising:
a sensor sensing a hitch angle between a vehicle and a trailer;
a steering input device providing a backing path of the trailer; and
a controller generating a steering command for the vehicle based on the hitch angle and the backing path, wherein the controller generates a countermeasure for operating the vehicle when the sensor fails to sense the hitch angle.

2. The trailer backup assist system of claim 1 , wherein the countermeasure includes at least one of a braking command, a powertrain command, and a steering command.

3. The trailer backup assist system of claim 1 , further comprising:
a steering wheel of the vehicle for commanding a steering angle of the vehicle, wherein the controller disengages the countermeasure when an external torque is applied to the steering wheel.

4. The trailer backup assist system of claim 3 , wherein the steering wheel includes a torque sensor for sensing an internal torque applied by a power assist steering system and the external torque applied by a driver of the vehicle.

5. The trailer backup assist system of claim 1 , wherein the countermeasure is generated after the hitch angle is not sensed for a threshold period of time, and wherein the countermeasure is configured to prevent a jackknife condition.

6. The trailer backup assist system of claim 1 , wherein the steering input device includes a rotatable knob configured to provide a curvature of the trailer, defining the backing path.

7. A sensor failure mitigation system for a trailer backup assist system, comprising:
a sensor measuring a hitch angle between a vehicle and a trailer; and
a controller detecting failure of the sensor to measure the hitch angle, engaging a countermeasure when the sensor fails, and disengaging the countermeasure upon a driver intervention to operate the vehicle.

8. The sensor failure mitigation system of claim 7 , further comprising:
a steering input device providing a backing path of the trailer, wherein the controller generates a steering command for the vehicle to guide the trailer along the backing path based on the hitch angle and a kinematic relationship.

9. The sensor failure mitigation system of claim 8 , further comprising:
a steering wheel of the vehicle for commanding a steering angle of the vehicle, wherein the controller disengages the countermeasure when an external torque is applied to the steering wheel.

10. The sensor failure mitigation system of claim 7 , wherein the countermeasure includes at least one of a braking command, a powertrain command, and a steering command.

11. The sensor failure mitigation system of claim 7 , further comprising:
a steering wheel of the vehicle having a torque sensor for sensing an internal torque applied by a steering system of the vehicle and an external torque applied by a driver of the vehicle for manually steering the vehicle, wherein the controller disengages the countermeasure when the external torque is sensed.

12. The sensor failure mitigation system of claim 7 , further comprising:
a brake control system of the vehicle sensing when a brake pedal is depressed, wherein the countermeasure is disengaged when the brake pedal is depressed.

13. The sensor failure mitigation system of claim 7 , wherein the countermeasure is configured to prevent at least one of a jackknife condition and an over-speed condition.

14. The sensor failure mitigation system of claim 7 , wherein the steering input device includes a rotatable knob configured to provide a curvature of the trailer, defining a backing path.

15. A method for mitigating sensor failure of a trailer backup assist system, comprising;
sensing a hitch angle between a vehicle and a trailer;
generating a steering command for the vehicle based on the hitch angle;
generating a countermeasure command for the vehicle when the hitch angle fails to be sensed; and
disengaging the countermeasure command upon a driver intervention.

16. The method of claim 15 , further comprising:
generating an alert for a driver of the vehicle when the hitch angle fails to be sensed.

17. The method of claim 15 , wherein the driver intervention includes at least one of sensing an external steering torque on a steering wheel and sensing a braking command on a brake pedal.

18. The method of claim 15 , wherein the steering command is generated based on a backing path for the trailer provided by a steering input device and a kinematic relationship between the vehicle and the trailer.

19. The method of claim 18 , wherein the steering input device includes a rotatable knob configured to provide a curvature of the trailer, defining the backing path, and wherein the countermeasure is configured to prevent a jackknife condition defined by the kinematic relationship.

20. The method of claim 15 , wherein the countermeasure includes at least one of a braking command, a powertrain command, and a steering command.

Assignees

• Ford Global Tech Llc

Inventors

• Lavoie Erick Michael

Classifications

• B60W2710/207

  Steering angle of wheels · CPC title

• B60W30/18036 Primary

  Reversing · CPC title

• B60W30/10 Primary

  Path keeping {(cruise control for automatically following a preceding vehicle B60W30/165)} · CPC title

• B60W2710/18

  Braking system · CPC title

• B60W2510/207

  Oversteer or understeer · CPC title