Aerial Grasping by Multi-Limbed Flying Robot SPIDAR Based on Vectored Thrust Control

Delivery by aerial robots is an emerging topic in many scenarios, such as logistics, construction industry, and disaster response. Compared to the standard styles that deploy cage or sling, grasping style by gripper can handle objects in various shapes. A multi-limbed structure with distributed vectorable rotors called SPIDAR shows a higher potential to grasp large object in a three-dimensional manner. Therefore, in this paper, we focus on the advanced usage of the vectored thrust forces to achieve aerial grasping by this robot. First, a vectored thrust control to avoid the aerointerference on the underwind segments (e.g., grasped object) during flight is proposed. Then, an optimization-based planning method that utilizes redundant vectored thrust forces for firm grasping is developed. Finally, we demonstrate the feasibility of the proposed flight control and grasp planning by performing challenging grasping and transporting motion with a spherical object of which the diameter is 0.6 m. To the best of our knowledge, this work is the first to achieve multi-finger-like grasping to carry a large object in midair.