Abstract

Given the profiles (self-occluding contours) of a surface undergoing fixed-axis rotation, it is possible to recover the shape and motion of the surface. The global symmetry of the envelope of profiles allows one to compute the projection of the axis of rotation. Once the projected axis is known, local measurements of the profiles are sufficient to determine the local surface, angular velocity and slant of the axis of rotation. It is also possible to find points on the profile where the image motion corresponds to the projected 3-D motion of points on the surface. This correspondence is instantaneous in the sense that the points that correspond are continually changing. The condition for a point on the profile to be in instantaneous correspondence is that its normal is parallel to the projected axis of rotation.

© 1991 Optical Society of America