Exploiting uncalibrated stereo on a UAV platform

Uncalibrated stereo imagery experimental and analytical results are presented for path planning and navigation. An Army Research and Development Engineering Command micro-size UAV was outfitted with two commercial cameras and flown over varied landscapes. Polaris Sensor Technologies processed the data post flight with an image correspondence algorithm of their own design. Stereo disparity (depth) was computed despite a quick assembly, image blur, intensity saturation, noise and barrel distortion. No camera calibration occurred. Disparity maps were computed at a processing rate of approximately 5 seconds per frame to improve perception. Disparity edges (treeline to ground, voids and plateaus) were successfully observed and confirmed to be properly identified. Despite the success of localizing this disparity edges sensitivity to saturated pixels, lens distortion and defocus were strong enough to overwhelm more subtle features such as the contours of the trees, which should be possible to extract using this algorithm. These factors are being addressed. The stereo data is displayed on a flat panel 3D display well suited for a human machine interface in field applications. Future work will entail extraction of intelligence from acquired data and the overlay of such data on the 3D image as displayed.