Wide-field optical flow information can benefit the navigation of small or micro unmanned aerial vehicles in GPS-degraded/denied environments, inspired by the study of insect/bird flights. This paper focuses on a flight-test evaluation of navigation information in wide-field optical flow, using flight data collected by a wide-angle camera installed on a fixed-wing unmanned aerial vehicle at altitudes ranging from 30 to 183 m above the ground. A comprehensive evaluation methodology is proposed for the comparison between optical flows computed from videos and the reference motion fields determined from conventional navigation sensors including GPS, a laser range finder, and inertial sensors. Seven setsofunmanned aerial vehicle flight data including a total of approximately 72,000 image frames are used for both full-flight temporal evaluation and representative interframe spatial evaluation of wide-field optical flow information for unmanned aerial vehicle navigation purposes. The evaluation results showed a good match between vision-derived optical flows and reference motion fields from conventional navigation sensors. Finally, one benchmark data set is shared at the authors' website for open access from the research community.
All Science Journal Classification (ASJC) codes
- Aerospace Engineering
- Computer Science Applications
- Electrical and Electronic Engineering