2 METRIC SOLUTIONS TO 3-DIMENSIONAL RECONSTRUCTION FOR AN EYE IN PUREROTATIONS

A problem in space perception concerns how a mobile observer acquires information about the structure of objects. Earlier research derived t he optic-flow equations for an eye undergoing pure rotations. It was s uggested that, by utilizing three points and two views, one can recove r the distance of points and the motion parameters. The radius of the eyeball was the metric unit. Yet the common view regards this problem as indeterminate. We derived a unique solution in the discrete case, w hich required three points and two views. However, when we observed a single bright point, a substantial amount of visual stability existed. We therefore derived a solution in the differential approach for a si ngle point, which is based on a distinction that we made between mathe matical and visual points. Both solutions were checked with a computer simulation and were found to be accurate, supporting the space percep tion in navigation (SPIN) theory.