Method for ascertaining an articulation angle, processing unit, and vehicle

A processing unit for a vehicle including a towing vehicle and a trailer the processing unit being configured to:

• determine a point cloud from at least one single image captured by a camera system, in which at least the trailer is imaged, wherein the point cloud comprises object points assigned to the trailer and wherein the at least one single image is captured when the trailer is not coupled to the towing vehicle;
• form at least one planar reference surface corresponding to a contiguous surface of the trailer from the adjacent object points of the point cloud that lie in a same plane, wherein the respective planar reference surface is in a fixed spatial orientation and/or a fixed spatial position relative to the trailer;
• read in at least one single image, in which the trailer coupled to the towing vehicle is imaged, and to determine at least one partial surface in this at least one single image read in;
• fit at least one previously formed planar reference surface to the at least one determined partial surface by applying a geometric transformation;
• and
• determine an articulation angle between the towing vehicle and the trailer as a function of a rotational component of the applied geometric transformation, wherein the rotational component of the applied geometric transformation characterizes a rotation of the planar reference surface about a pivot axis of the trailer.

A method for determining an articulation angle between a towing vehicle and a trailer coupled to the towing vehicle, wherein the trailer can be imaged in single images with single-image pixels using a camera system, the method comprising:

• determining a point cloud from at least one single image in which at least the trailer is represented, wherein the point cloud comprises object points assigned to the trailer;
• forming at least one planar reference surface from adjacent object points of the point cloud that lie in a same plane, wherein the respective planar reference surface is in a fixed spatial orientation and/or a fixed spatial position relative to the trailer;
• reading in at least one single image, in which the trailer coupled to the towing vehicle is imaged, and determining at least one partial surface in this at least one single image read in;
• fitting the at least one planar reference surface to the at least one determined partial surface of the read-in single image by applying a geometric transformation;
• and
• determining the articulation angle between the towing vehicle and the trailer as a function of a rotational component of the applied geometric transformation, wherein the rotational component of the applied geometric transformation characterizes a rotation of the planar reference surface about a pivot axis of the trailer,
• wherein the at least one planar reference surface is defined from adjacent object points which lie in the same plane, such that the planar reference surface can be assigned to a region delimited or delimitable by color and/or structure comprising adjacent single-image pixels in the at least one single image, and
• wherein the planar reference surface is formed from the adjacent object points of the point cloud which lie in the same plane and/or to which single-image pixels with the same or at least similar color values and/or intensity values in the at least one single image are assigned.