Control for trailer backup assist system
In one embodiment of the disclosed subject matter, a trailer backup assist system includes a sensor that senses a measured hitch angle between a vehicle and a trailer. The system also provides an input module that receives a desired curvature of the trailer. A controller of the system includes a curvature regulator determining a desired hitch angle based on the desired curvature and a steering angle of the vehicle. In addition, the controller of the system includes a hitch angle regulator generating a steering angle command based on the desired hitch angle and the measured hitch angle. In this embodiment, the controller is configured to operate the trailer backup assist system irrespective of the attached trailer having a conventional tongue or a gooseneck tongue.
1. A trailer backup assist system comprising:
a hitch sensor sensing a measured hitch angle between a vehicle and a gooseneck trailer;
a steering sensor sensing a steering angle of the vehicle;
an input module receiving a driver input desired curvature of the gooseneck trailer; and
a controller comprising a curvature regulator for determining a desired dynamic hitch angle to reverse the trailer along the driver input desired curvature based on the driver input desired curvature, the steering angle, and kinematic information of the gooseneck trailer and the vehicle, said controller further comprising a hitch angle regulator having feedback linearization for generating a steering angle command for the vehicle to steer the vehicle and the trailer at the desired dynamic hitch angle based on the desired dynamic hitch angle, the measured hitch angle and a velocity of the vehicle, wherein the curvature regulator and the hitch angle regulator operate in concert.
2. The trailer backup assist system of claim 1 , wherein the hitch angle regulator further prevents the desired dynamic hitch angle from exceeding a jackknife angle.
3. The trailer backup assist system of claim 1 , wherein the input module includes a rotational control input device that is rotatable between a first position corresponding to a first curvature of the trailer and a second position corresponding to a second curvature of the trailer.
4. The trailer backup assist system of claim 1 , wherein a distance is defined between a rear axle of the vehicle and a pivoting connection between the vehicle and the gooseneck trailer, such that the controller is configured to generate the steering angle command consistent with the desired curvature when the distance is substantially equal to zero.
5. The trailer backup assist system of claim 1 , wherein the gooseneck trailer couples with the vehicle at a fifth wheel connector proximate a rear axle of the vehicle, defining a pivoting connection substantially aligned with the rear axle of the vehicle, and wherein the controller generates the steering angle command as a function independent of a distance between the rear axle and the pivoting connection.
6. The trailer backup assist system of claim 1 , wherein the vehicle has front wheel steering without rear wheel steering, wherein the steering angle command controls the front wheel steering.
7. A trailer backup assist system comprising:
a sensor sensing a measured hitch angle between a vehicle and a trailer, wherein the vehicle has a pivoting connection with the trailer that is substantially aligned with a rear axle of the vehicle;
an input module receiving a driver input desired curvature of the trailer; and
a controller comprising:
a curvature regulator determining a desired dynamic hitch angle to reverse the trailer along the driver input desired curvature based on the driver input desired curvature and a steering angle of the vehicle; and
a hitch angle regulator comprising feedback linearization for generating a steering angle command to steer the vehicle and the trailer at the desired dynamic hitch angle based on the desired dynamic hitch angle, the measured hitch angle, and a velocity of the vehicle, wherein the curvature regulator and the hitch angle regulator operate in concert.
8. The trailer backup assist system of claim 7 , wherein the hitch angle regulator includes a PI controller having gain terms based on a length of the trailer.
9. The trailer backup assist system of claim 7 , wherein the hitch angle regulator prevents the desired dynamic hitch angle from exceeding a jackknife angle.
10. The trailer backup assist system of claim 7 , wherein the curvature regulator determines the desired dynamic hitch angle based on kinematic information of the vehicle and the trailer.
11. The trailer backup assist system of claim 7 , wherein the curvature regulator determines the desired dynamic hitch angle based on the steering angle as determined by the hitch angle regulator.
12. The trailer backup assist system of claim 7 , wherein the input module includes a trajectory planner that generates a path for the trailer with the desired curvature provided along the path.
13. The trailer backup assist system of claim 7 , wherein the trailer includes a gooseneck tongue that couples with the vehicle proximate a rear axle of the vehicle, such that a distance between the rear axle of the vehicle and a pivoting connection between the vehicle and the trailer is substantially equal to zero.
14. The trailer backup assist system of claim 7 , wherein the vehicle has front wheel steering, wherein the steering angle command controls the front wheel steering.
15. A method for operating a trailer backup assist system, comprising:
sensing a measured hitch angle between a vehicle and a trailer;
sensing a steering angle of the vehicle;
receiving an input desired curvature of the trailer;
determining with a curvature regulator a desired dynamic hitch angle to reverse the trailer along the input desired curvature; and
generating with a hitch angle regulator a steering angle command for the vehicle to steer the vehicle and the trailer at the desired dynamic hitch angle using feedback linearization and based on the desired dynamic hitch angle and the measured hitch angle, wherein the curvature regulator and the hitch angle regulator operate in concert.
16. The method of claim 15 , wherein the steering angle command is generated further based on a velocity of the vehicle.
17. The method of claim 15 , further comprising:
determining a jackknife angle based on a length of the trailer and preventing the desired dynamic hitch angle from exceeding the jackknife angle.
18. The method of claim 15 , wherein the desired curvature is provided by a trajectory planner that generates a path for the trailer with the desired curvature provided along the path.
19. The method of claim 15 , wherein a distance is defined longitudinally between a rear axle of the vehicle and a pivoting connection between the a hitch ball on the vehicle and a gooseneck tongue on the trailer, such that the steering angle command is generated consistent with the desired curvature when the distance is substantially equal to zero.
20. The method of claim 15 , wherein the vehicle has a pivoting connection with the trailer that is substantially aligned with a rear axle of the vehicle.