Light-weight quadrotor with on-board absolute vision-aided navigation

This paper presents a novel small unmanned aerial system which can operate independently and navigate using visual sensors. The basis of the system is a 600 gram quadrotor platform with sonar, inertial sensors and a camera. All processing is performed onboard the vehicle on a lightweight and powerful computer. Vehicle navigation is provided by a two part system. A Bierman Thornton extended Kalman filter (BTEKF) generates vehicle state and image feature estimates in a visual simultaneous localization and mapping (SLAM) formulation. Absolute position updates are provided to the BTEKF by a particle filter map-matching technique. Simulation and flight test results demonstrate the capabilities of the system to both navigate in an unknown environment with minimal drift while also showing the ability to eliminate drift when a priori known visual information is visible.