Suspended load motion control using multicopters

This paper presents a distributed kinematic control law for group coordination for several multicopters and a payload suspended with wires from each multicopter. The complete system with constraints on the wires are modeled in 6 degrees of freedom (DOF), using the Udwadia-Kalaba equation. Velocity controllers for the multicopters are developed to realize the desired motion set by the kinematic controller. This results in a system where the group of multicopters are able to maneuver the payload to a desired position while keeping a desired formation. The results are verified by simulations.

I. Introduction

In many years, especially in the military, a lot of research has been done on modelling and control of a system consisting of flying vehicles transporting a payload suspended with ropes. Helicopters and other multi-rotors are particularly useful for this task due to their hovering ability. Applications span from crate transportation and fire extinguishing, to geo-surveying and mine-detection [1].