Student Research

Autonomous Collision Avoidance of UAVs Utilizing ABS-D Transponders

If UAVs are to be successfully integrated into U.S. national airspace, the ability to perform autonomous collision avoidance between both manned and unmanned aircraft is a necessity. This poster presents a method for collision avoidance utilizing Automatic Dependent Surveillance - Broadcast (ADS-B) transponders which will be required in all manned aircraft by 2020. These devices broadcast and receive global position of all similarly equipped aircraft in a 100-nautical mile vicinity. A Sig Kadet Senior and a Hangar 9 Valiant fixed wing aircraft are used as flight platforms to test autonomous collision avoidance. These aircraft will include ADS-B transponders, a Pixhawk autopilot and an Intel NUC as the primary components of the avionics system. The uniquely developed algorithm is compiled in a Linux environment and uses MAVLink protocols to send off-board commands to the autopilot. The collision avoidance algorithm uses kinematic and circular motion equations to predict the future positions of both aircraft and employ an avoidance maneuver at a constant altitude. This system is demonstrated through simple ground tests, and subsequently moving on to full-system flight tests.