Optical Flow and Motion Estimation Modules are hardware subsystems that measure relative motion within visual scenes by analyzing frame-to-frame image changes, providing real-time feedback for stability, tracking, and navigation. Optical flow sensors have revolutionized how drones maintain position without GPS. After years of flying in challenging environments from indoor spaces to under dense tree canopies, I've come to rely on these remarkable devices for stable hovering and precise movement when satellite navigation. Optical Flow uses a downward facing camera and a downward facing distance sensor for velocity estimation. The video below shows PX4 holding position using the Ark. Source suppliers and manufacturers of optical flow sensors for drones, UAVs, and other unmanned systems. They support responsive control by supplying low-latency motion data.
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