Scansorial Landing and Perching

We describe an approach whereby small unmanned aircraft can land and perch on outdoor walls. Our prototype uses an ultrasonic sensor to initiate a pitch-up maneu-ver as it flies toward a wall. As it begins to stall, it contacts the wall with compliant “feet ” equipped with rows of miniature spines that engage asperities on the surface. A nonlinear hierarchical suspension absorbs the kinetic energy and controls contact forces in the normal and tangential directions to keep spines engaged during the landing process. Future work will include powered take-offs and maneuvering in contact with the wall.