Multiaperture Visual Velocity Measurement Method Based on Biomimetic Compound-Eye for UAVs

Autonomous velocity measurement technology based on optical flow plays an important role in applications of the Internet of Things. However, robust velocity measurement results need to provide a robust optical flow field and distance to the ground, especially for complex ground scenes. To solve this problem, this article proposes a visual velocity measurement method based on a $3\times3$ camera-array multiaperture biomimetic compound-eye imaging system. The multiaperture optical flow field is first obtained from compound-eye through multiscale analysis and Bayes threshold processing. The real distance to the ground is then obtained by extracting the disparity information of nine apertures for adaptive depth estimation. The velocity measurement error is less than 0.6 m/s in low-altitude (8 and 13 m) flight scenarios with multiple obstacles.