Automotive Radar-Based Hitch Angle Tracking Technique for Trailer Backup Assistant Systems

Abstract

We propose a technique for trailer angle detection (TAD) for use in advanced trailer backup assistance system (TBAS) for semi-autonomous or full-autonomous backup maneuver. TBAS incorporates a combined trailer-tow-vehicle kinematic model, which is requires an estimate of the hitch angle. The proposed radar-based TAD model, for the estimate of the hitch angle, processes reflections acquired from the mmWave radars situated at the rear side of the vehicle, to detect the trailer and track its orientation in relation to the tow-vehicle. This technique is based on the tracking of individual points in the merged radars point-cloud. Each tracked point is considered as a hitch angle estimator. Using the current and past position information of a point, the model estimates the current hitch angle. To offer an accurate and reliable estimation for the hitch angle, the model fuses the estimated hitch angle by all estimators, as well as the yaw rate of the vehicle. To track each individual radar point, the model employs the extended Kalman filter, which is robust to the noisy radar measurements. In the presence of strong and persistence reflections from the trailer, the model can track the trailer successfully and return the hitch angle with a reliability measure equal to 90%.