Preliminary test showing how the optic flow field can be used to estimate the slope of the landing surface. The drone takes off at the top of a stairs and is set to fly forward with a fixed speed. The onboard images are processed for determining the optic flow and subsequently the slope of the surface. The drone lands automatically when it estimates the slope to be zero, that is when it reaches the bottom of the stairs.
The optic flow algorithm is described in the paper: (2013), de Croon, G.C.H.E., and Ho, H.W., and De Wagter, C., and van Kampen, E., and Remes B., and Chu, Q.P., "Optic-flow based slope estimation for autonomous landing", in the International Journal of Micro Air Vehicles, Volume 5, Number 4, pages 287 – 297.
MATLAB code at: mavlab.tudelft.nl
