A Bionics-Based Recovery Strategy for Micro Air Vehicles

Micro air vehicles' (MAVs) movements can be significantly affected by physical contact with unknown moving objects (UMOs) from a random direction. To address this problem, low-latency sensors (cameras or radars) and high-speed processors are installed in six directions of aerial vehicles. However, this method is limited by hardware costs, load, and energy. In this article, a fast recovery strategy for MAVs is proposed, which is inspired by the recovery manoeuvre of mosquitoes hit by raindrops. When hit by falling raindrops, mosquitoes will descend along the falling direction of raindrops to gradually counteract the kinetic energy of the impact induced by the raindrops. During the descent, mosquitoes will gradually tilt to one side but move in the opposite direction, and finally deviate from the falling route of raindrops. To simulate the recovery strategy, a micro aerial robot called RobMos is designed. The RobMos is an overactuated system that can decouple the position control from the attitude control. Using the recovery strategy, the robot can quickly recover to a stable attitude after being impacted by UMOs. An onboard inertial measurement unit is used to estimate the impact location. Finally, the prototype can bear the impact of objects that are two times its own weight. Moreover, the generalizability of this strategy is also discussed, and it is proved that the RobMos can even recover attitude after being hit by the UMO in a lateral direction.