Invariants and omnidirectional vision for robot object recognition

This paper introduces the use of projective invariants for object recognition using omnidirectional vision. The catadioptric image formation is modeled with a two-step mapping via the sphere using the conformal geometric algebra. Also, the projective invariants are calculated using the conformal geometric algebra. Furthermore, we show that the projective invariants in a plane are equivalent to the invariants of circles in the unit sphere. This equivalence induces us to project features from the catadioptric image to the sphere, calculate their invariants and use these invariants to recognize objects.