Targetless vehicular camera misalignment correction method

A method of correcting misalignment of a vehicular camera mounted at a vehicle, said method comprising:

• at a vehicle assembly plant, disposing a plurality of cameras at a vehicle so as to have respective fields of view exterior of the vehicle, wherein each camera of the plurality of cameras comprises a two-dimensional photosensor array having a plurality of photosensing elements;
• providing a processor at the vehicle;
• calibrating each camera of the plurality of cameras at the vehicle while the vehicle is at the vehicle assembly plant, wherein calibrating each camera of the plurality of cameras comprises calibrating a yaw angle of each camera, a pitch angle of each camera and a roll angle of each camera;
• capturing frames of image data with each camera of the plurality of cameras as the vehicle is driven along an arbitrary path along a road being traveled by the vehicle;
• processing, via the processor, frames of image data captured by each camera of the plurality of cameras as the vehicle is driven along the arbitrary path;
• receiving, at the processor, vehicle data representative of vehicle kinematic motion as the vehicle is driven along the arbitrary path;
• wherein the received vehicle data comprises at least one selected from the group consisting of (i) data related to steering of the vehicle and (ii) data related to speed of the vehicle;
• wherein the received vehicle data is carried by a communication bus system of the vehicle;
• responsive to processing by the processor of frames of image data captured by each camera of the plurality of cameras as the vehicle is driven along the arbitrary path, determining at least one respective feature present in the respective frames of image data captured by each respective camera and tracking the determined at least one respective feature across the respective frames of image data captured by each respective camera;
• responsive to the tracking of the determined at least one respective feature across the respective frames of image data captured by each respective camera, and responsive at least in part to the received vehicle data representative of the vehicle kinematic motion as the vehicle is driven along the arbitrary path, determining misalignment of a respective camera of the plurality of cameras;
• wherein the determined misalignment comprises misalignment of at least one selected from the group consisting of (i) the yaw angle of the respective camera, (ii) the pitch angle of the respective camera and (iii) the roll angle of the respective camera;
• responsive to the determination of misalignment of the respective camera of the plurality of cameras, correcting the determined misalignment of the respective camera;
• and
• wherein correcting the determined misalignment of the respective camera is achieved (i) without use of a target in the field of view of the respective camera as the vehicle is driven along the arbitrary path and (ii) without processing of frames of image data captured by the respective camera that are representative of a target in the field of view of the respective camera as the vehicle is driven along the arbitrary path.

A method of correcting misalignment of a vehicular camera mounted at a vehicle, said method comprising:

• at a vehicle assembly plant, disposing a plurality of cameras at a vehicle so as to have respective fields of view exterior of the vehicle, wherein each camera of the plurality of cameras comprises a two-dimensional CMOS photosensor array having a plurality of photosensing elements;
• wherein the plurality of cameras comprises (i) a rear camera disposed at a rear portion of the vehicle and having a rearward field of view, (ii) a driver-side camera disposed at a driver-side exterior rearview mirror assembly of the vehicle and at least having a generally sideward and rearward field of view and (iii) a passenger-side camera disposed at a passenger-side exterior rearview mirror assembly of the vehicle and at least having a generally sideward and rearward field of view;
• providing a processor at the vehicle;
• calibrating each camera of the plurality of cameras at the vehicle while the vehicle is at the vehicle assembly plant, wherein calibrating each camera of the plurality of cameras comprises calibrating a yaw angle of each camera, a pitch angle of each camera and a roll angle of each camera;
• capturing frames of image data with each camera of the plurality of cameras as the vehicle is driven along an arbitrary path along a road being traveled by the vehicle;
• processing, via the processor, frames of image data captured by each camera of the plurality of cameras as the vehicle is driven along the arbitrary path;
• receiving, at the processor, vehicle data representative of vehicle kinematic motion as the vehicle is driven along the arbitrary path;
• responsive to processing by the processor of frames of image data captured by each camera of the plurality of cameras as the vehicle is driven along the arbitrary path, determining at least one respective feature present in the respective frames of image data captured by each respective camera and tracking the determined at least one respective feature across the respective frames of image data captured by each respective camera;
• responsive to the tracking of the determined at least one respective feature across the respective frames of image data captured by each respective camera, and responsive at least in part to the received vehicle data representative of the vehicle kinematic motion as the vehicle is driven along the arbitrary path, determining misalignment of a respective camera of the plurality of cameras;
• wherein the determined misalignment comprises misalignment of at least one selected from the group consisting of (i) the yaw angle of the respective camera, (ii) the pitch angle of the respective camera and (iii) the roll angle of the respective camera;
• responsive to the determination of misalignment of the respective camera of the plurality of cameras, correcting the determined misalignment of the respective camera;
• and
• wherein correcting the determined misalignment of the respective camera is achieved (i) without use of a target in the field of view of the respective camera as the vehicle is driven along the arbitrary path and (ii) without processing of frames of image data captured by the respective camera that are representative of a target in the field of view of the respective camera as the vehicle is driven along the arbitrary path.