Improving the field of regard of a time-of-flight camera for UAV mapping and collision avoidance in cluttered environments

The modern urban environment presents a number of significant challenges to unmanned aerial vehicle (UAV) operations. Denied access to navigation satellite systems, a UAV is entirely reliant on its on-board sensors for navigation, where scene information rates are necessarily high. Time-of-flight (ToF) cameras have the ability to produce depth images of a scene at high acquisition rates with low computational overheads. This paper outlines the operation of a ToF ranging camera that uses the continuous-wave, indirect ToF ranging method and utilises a novel single-photon avalanche-diode (SPAD) sensor array. To improve the camera‟s field of regard, an adaptation of the original system, incorporating a rotating mirror and 360 o illumination scheme, was developed. The effect of motion artefacts due to rotation are assessed for different integration periods, and a 360o scene is presented.