Path-Following and Attitude Control of a Payload Using Multiple Quadrotors

This paper addresses the problem of carrying a rod-shaped load between a certain origin and a desired goal using unmanned aerial vehicles (UAV). The load is carried via flexible cables by two quadrotors, one at each end of the bar. Positioning, orientation, and path-following tasks are here addressed. The robots and the load are modeled as a single system, using a virtual structure framework for robot formation and a nonlinear controller based on feedback linearization to handle the load oscillations and accomplish the missions. Results obtained running a real experiment using two AR. Drone quadrotors to carry an aluminum bar are presented through illustrations and videos, which validate the proposed system.