Ground and Flight Tests of an Unmanned Rotorcraft with Cable-Driven Robotic Landing Gear

Robotic landing gear enhances the landing capabilities of vertical take-off and landing aircraft on sloped, rough, and even moving landing surfaces. This research demonstrates the integration and systematic testing of a robotic landing gear system for the commercial S-100 Camcopter, expanding the aircraft’s landing capabilities to currently inaccessible terrains with slopes at and above 15°. An overview of the mechanical design, sensors, and controller as integrated into the S-100 rotorcraft is provided along with expected landing performance from simulations tools. The system is then demonstrated using ground and flight experiments, and performance metrics are found to match design metrics. An asymmetry in left and right leg landings during flight testing is observed and analyzed. Lastly, cross-coupling of pitch and roll rates induced by the rotor is discussed as a cause of the asymmetry on this three-legged rotorcraft.