US Patent 11608112 Vehicular trailering assist system with targetless calibration of trailer cameras

A vehicular trailering assist system includes at least one camera disposed at a trailer hitched to a hitch of a vehicle, and an electronic control unit (ECU). The ECU determines, during a first stage of a calibration maneuver of the vehicle and trailer, image coordinates of at least one ground feature point. The ECU, responsive to determining image coordinates of the at least one ground feature point, estimates orientation parameters of the camera based at least on the determined image coordinates and known intrinsic camera parameters. Responsive to estimating the orientation parameters of the camera, and based on the determined parameters of the camera, the ECU determines location of the at least one camera at the trailer.