View-Based Point-to-Point Navigation Using Spherical Harmonics

We present a view-based method for steering a robot in a network of positions; this includes navigation along a prerecorded path, but also allows for arbitrary movement of the robot between adjacent positions in the network. The approach uses an upward-looking omni- directional camera; even a very modest quality of the optical system is sufficient, since all views are represented in terms of low-order basis functions (spherical harmonics). Motor control signals for the robot are derived from a differential matching approach; the computation of the involved gradient information is extremely simplified by exploiting the fact that all images are represented in terms of basis functions. The via- bility of the approach for steering the robot has been shown in extensive simulations using photorealistic views; the validity of these simulations in comparison to a tangible system implementation operating in a real indoor scene has been shown in previous investigations (5).