An algorithm for terrain avoidance using optical flow

A technique for terrain following using optical flow is presented. The technique is inspired by the distribution of facets in the compound eyes of many flying insects. The image interpolation algorithm is used to compute accurate optical flow values and subsequently, height above ground. Some novel techniques to allow the camera to be pointed in arbitrary directions rather than simply downwards were implemented. The algorithm was tested extensively in simulation using a simple control law based on the optical flow system updating the set point of a barometric altitude driven control loop. Ongoing field trials are producing promising results