Adaptive Cooperative Load Transportation by a Team of Quadrotors With Multiple Constraint Requirements

Cable-suspended load carried by multiple unman- ned aerial vehicles (UAVs) has applications in many areas. However, most existing aerial load transportation works are tailored to a specific type of load transportation tasks, or assume simplified system models or transportation scenarios. Furthermore, no existing works on this topic can provide a unified framework to address multiple performance and safety constraints during the cooperative transportation operation. In this paper, we propose and investigate a new constrained cooperative control architecture for an UAV team, which are collaboratively carrying a three-dimensional load, subject to multiple user-defined time-varying performance and safety constraint requirements. A unified framework using universal barrier functions has been proposed to deal with different types of constraint requirements. Moreover, control saturation and uncertainties in UAV inertia matrices are dealt with by employing adaptive estimators. Exponential convergence on the distance and attitude tracking errors can be guaranteed by the algorithm. Lastly, we discuss a simulation example that further shows the efficacy of the proposed cooperative control framework.