Trailer path curvature control for trailer backup assist

An electronic control system having a set of instructions tangibly embodied on a non-transitory processor-readable medium thereof, the set of instructions are accessible from the non-transitory processor-readable medium by at least one data processing device of the electronic controller system for being interpreted thereby, and the set of instructions is configured for causing the at least one data processing device to carry out operations for:

• receiving trailer path curvature information characterizing a desired curvature for a path of travel of a trailer during backing of the trailer by a vehicle towably coupled thereto, the desired curvature is relative to a zero curvature position defined by backward movement of the trailer in a substantially straight line defined by a centerline longitudinal axis of the trailer;
• determining vehicle steering information through assessment of kinematical information of a system defined by the vehicle and the trailer, assessment of the kinematical information is performed as a function of the trailer path curvature information;
• and
• generating a steering command for a steering system of the vehicle as a function of the vehicle steering information.

A trailer backup assist system for a vehicle, comprising:

• a trailer backup steering input apparatus for outputting a trailer path curvature signal approximating a desired curvature for a path of travel of a trailer towably coupled to the vehicle, the desired curvature is relative to a zero curvature position defined by backward movement of the trailer in a straight path defined by a centerline longitudinal axis of the trailer;
• a trailer backup assist control module coupled to the a trailer backup steering input apparatus and configured for determining vehicle steering information as a function of the trailer path curvature signal;
• and
• an electric power assist steering system coupled to the trailer backup assist control module and configured for controlling steering of steered wheels of the vehicle as a function of the vehicle steering information.

A method of controlling a path of travel of a trailer towably coupled to a vehicle during backing of the trailer by the vehicle, comprising:

• receiving trailer angle information from a trailer angle detection apparatus of a vehicle having a trailer attached thereto, wherein the trailer angle information is generated as a function of an angular displacement between the vehicle and the trailer;
• receiving trailer path curvature information characterizing a desired curvature for a path of travel of the trailer from a trailer backup steering input apparatus of the vehicle, the trailer backup steering input apparatus includes a rotational control input device positionable at a zero curvature commanding position and at positions within opposing rotational ranges of motion relative to the zero curvature commanding position and the trailer steering information is derived from at least one of an amount of rotation of the rotational control input device with respect to the zero curvature commanding position, a rate movement of the rotational control input device, and a direction of movement of the rotational control input device with respect to the zero curvature commanding position;
• determining vehicle steering information through assessment of kinematical information of a system defined by the vehicle and the trailer, assessment of kinematical information is performed as a function of the trailer path curvature information;
• generating a steering command for a steering system of the vehicle as a function of the vehicle steering information;
• and
• controlling a power steering system of the vehicle using vehicle steering information as the trailer is being backed by the vehicle, the vehicle steering information is generated as a function of the trailer angle information and the trailer path curvature information.

A trailer backup steering system for a vehicle, comprising:

• a trailer angle detection apparatus configured for outputting a signal generated as a function of an angle between the vehicle and a trailer attached to the vehicle;
• a trailer backup steering input apparatus for outputting a trailer path curvature signal approximating a desired curvature for a path of travel of a trailer towably coupled to the vehicle, the desired curvature is relative to a zero curvature position defined by backward movement of the trailer along a straight path defined by a centerline longitudinal axis of the trailer, the trailer backup steering input apparatus including a knob and a knob movement sensing device coupled to the knob for sensing movement of the knob, the knob is biased to an at-rest position between opposing rotational ranges of motion, the at-rest position corresponds to the zero curvature position, the knob movement sensing device outputs a signal generated as a function of at least one of an amount of rotation of the knob with respect to the at-rest position, a rate movement of the knob, and a direction of movement of the knob with respect to the at-rest position;
• a trailer backup assist control module coupled to the a trailer backup steering input apparatus and configured for determining vehicle steering information as a function of the trailer path curvature signal;
• and
• a power-steering assist system coupled to a trailer angle detection apparatus, the trailer backup steering input apparatus, and the trailer backup assist control module, the power-steering assist system includes a control module structure configured for generating power steering system control information as a function of the trailer angle detection apparatus signal and the backup steering input apparatus signal and controlling steering of steered wheel of the vehicle as a function of the vehicle steering information.