TRAILER SWAY MITIGATION USING MEASURED DISTANCE BETWEEN A TRAILER AND A TOW VEHICLE

• US 20110022282A1
• Filed: 07/24/2009
• Published: 01/27/2011
• Est. Priority Date: 07/24/2009
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH, Robert Bosch LLC (Robert Bosch GmbH)
• Original Assignee: Robert Bosch GmbH
• Inventors: Hoetzer, Dieter, Wu, Hsien-cheng
• Granted Patent: US 8,838,353 B2
• Time in Patent Office: Days
• US Class Current: 701/70
• CPC Class Codes: B60D 1/245 for facilitating push back or parking of trailers
• CPC Class Codes: B60D 1/30 for sway control , e.g. stabilising or anti-fishtail devices; Sway alarm means
• CPC Class Codes: B60D 1/58 Auxiliary devices
• CPC Class Codes: B60T 2230/06 Tractor-trailer swaying
• CPC Class Codes: B60T 7/20 specially for trailers, e.g. in case of uncoupling of or overrunning by trailer inertia-actuated overrun brakes B60T13/08
• CPC Class Codes: B60T 8/1708 for lorries or tractor-trailer combinations
• CPC Class Codes: B60T 8/246 Change of direction
• CPC Class Codes: B60T 8/248 Trailer sway, e.g. for preventing jackknifing

Abstract

A method of controlling a vehicle and a trailer. The vehicle has a front and a rear end, and the trailer is coupled to the rear end. The method includes sensing a plurality of vehicle characteristics, sensing a distance between the vehicle and the trailer with at least one sensor positioned on the rear end of the vehicle, determining an oscillatory action of the trailer based on the sensed distance, and applying a braking force on at least one wheel of the vehicle in response to the oscillatory action.

Claims

1. A method of controlling a vehicle and a trailer, the vehicle having a front and a rear end and the trailer coupled to the rear end, the method comprising:

sensing a plurality of vehicle characteristics;

sensing a distance between the vehicle and the trailer with a sensor positioned on the rear end of the vehicle;

determining an oscillatory action of the trailer based on the sensed distance; and

applying a braking force on at least one wheel of the vehicle in response to the oscillatory action.

2. The method of claim 1, further comprising

calculating a plurality of target vehicle characteristics;

comparing each of the plurality of vehicle characteristics to a corresponding one of the plurality of target vehicle characteristics to determine an error signal; and

calculating the braking force based at least partially on the error signal.

3. The method of claim 1, wherein the sensor includes an ultrasonic sensor.

4. The method of claim 3, wherein sensing the distance between the vehicle and the trailer further comprises emitting an ultrasonic pulse from the ultrasonic sensor coupled to the rear end of the vehicle, receiving a reflection of the ultrasonic pulse with the ultrasonic sensor, calculating an amount of time to receive the reflection, and determining the distance based on the amount of time.

5. The method of claim 1, wherein the sensor includes a radar sensor.

6. The method of claim 1, wherein the plurality of vehicle characteristics include at least one of a steering angle, an engine torque, a wheel speed, a brake pressure, a lateral acceleration, and a yaw rate.

7. The method of claim 1, further comprising determining a sway angle of the trailer.

8. The method of claim 1, further comprising sensing a second distance between the vehicle and the trailer, and determining the oscillatory action of the trailer based on the first and second distances.

9. The method of claim 1, wherein applying the braking force further comprises applying one of a symmetric braking force and an asymmetric braking force.

10. The method of claim 9, further comprising applying asymmetric braking force if the change in a measured sway angle is greater than zero.

11. A system for controlling a vehicle and a trailer, the vehicle having a front end and a rear end and the trailer coupled to the rear end, the system comprising:

a plurality of vehicle characteristic sensors each configured to output a sensor signal;

at least one distance sensor coupled to the rear end of the vehicle, the at least one distance sensor configured to sense a distance between the rear end and the trailer and to output a distance signal indicative of the sensed distance;

an electronic control unit coupled to the vehicle and configured to receive the sensor signals and the distance signal, the electronic control unit configured to determine an oscillatory action of the trailer based on at least one of the sensor signals and the distance signal, and to apply a braking force to at least one wheel of the vehicle in response to the oscillatory action.

12. The system of claim 11, wherein the distance sensor is an ultrasonic sensor.

13. The system of claim 11, wherein the distance sensor is a radar sensor.

14. The system of claim 11, further comprising a second distance sensor coupled to the rear end, the second distance sensor spaced from the first distance sensor, wherein the electronic control unit is configured to receive a first distance signal from the first distance sensor and a second distance signal from the second distance sensor, and wherein the electronic control unit determines the oscillatory action of the trailer based on the first distance signal and the second distance signal.

15. The system of claim 11, wherein the plurality of vehicle characteristic sensors include at least one of a steering angle sensor, an engine torque sensor, a wheel speed sensor, a braking system pressure sensor, a lateral acceleration sensor, and a yaw rate sensor.

16. The system of claim 11, wherein applying the braking force includes one of applying a symmetric braking force and applying an asymmetric braking force to the wheels of the vehicle.

17. The system of claim 11, wherein the electronic control unit determines a target trailer distance based on the sensor signals, compares the target trailer distance to the distance signal to calculate an error signal, and applies one of a symmetric braking force and an asymmetric braking force to the wheels of the vehicle in response to the error signal.

18. The system of claim 17, wherein the electronic control unit applies the symmetric braking force when the error signal is above a first threshold value and applies the asymmetric braking force when the error signal is equal to or below the first threshold value and above a second threshold value.