US Patent 11206754 Depth sensing with absolute position and temperature compensation

An agricultural machine includes a frame, an arm pivotally coupled to the frame at a first end of the arm, and a target element on the first end of the arm. The target element is configured to rotate with the arm, and includes an outer surface and a projection extending away from the outer surface. The agricultural machine also includes a first sensor fixed to the frame. The first sensor is configured to detect the outer surface. The agricultural machine also includes a second sensor fixed to the frame. The second sensor is configured to detect the projection.