Optical flow sensor integrated navigation system for quadrotor in GPS-denied environment

The issues about navigation precision and indoor hovering of micro aerial vehicles (MAV) have been discussed frequently nowadays. This practical study presented a dedicated design for indoor hovering that is more precise than using GPS positioning. We adapted optical flow sensors and ultrasound sensors to comply indoor/outdoor hover mode. This design is safer, cheaper, and easier for users to control the MAV flight. The practical results showed the proposed scheme could reduce the errors of navigation parameters and achieve stable hovering performance under different conditions of lighting.