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Optical Flow Based Obstacle Avoidance for Multi-rotor Aerial Vehicles

The miniaturization of multi-rotor aerial vehicles (MAVs) poses challenges to autonomous navigation. Cameras are preferred due to the limited payload of MAVs. In this paper, we present an optical flow (OF)-based approach for obstacle avoidance in indoor environments with a payload constrained MAV. Our approach mainly utilizes Time-to-Contact (TTC) and balance strategy (BS), two basic principles demonstrated effectively in many different obstacle avoidance systems. Free spaces through which a MAV can fly are estimated by TTC. BS is used to guide a MAV flying in a collision free path. Our approach is implemented in the framework of Robot Operating System (ROS). The simulation demonstrates the effectiveness of the approach.