Optical flow technology integrates camera modules, image processors, and motion estimation algorithms to deliver high-frequency positional updates. These updates allow onboard flight controllers to maintain stability, achieve precise hovering, and execute smooth trajectory. Optical Flow uses a downward facing camera and a downward facing distance sensor for velocity estimation. It can be used to determine speed when navigating without GNSS — in buildings, underground, or in any other GNSS-denied environment. The PX4FLOW is not yet supported in Plane or Rover. The PX4FLOW (Optical Flow) Sensor is a specialized high resolution downward pointing camera module and a 3-axis gyro that uses the. The Holybro H-Flow is a compact o ptical flow and distance sensor module that combines a PixArt PAA3905E1 optical flow sensor, a Broadcom AFBR-S50LV85D distance sensor, and an InvenSense ICM-42688-P 6-axis IMU. If you're interested in the field of robotics and computer vision systems, you've likely heard of optic flow sensors.
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