Asymmetric Collaborative Bar Stabilization Tethered to Two Heterogeneous Aerial Vehicles

<p>We consider a system composed of a bar tethered to two unmanned aerial vehicles (UAVs), where the cables behave as rigid links under tensile forces, and with the control objective of stabilizing the bar&#39;s pose around a desired pose. Each UAV is equipped with a PID control law, and we verify that the bar&#39;s motion is decomposable into three decoupled motions, namely a longitudinal, a lateral and a vertical. We then provide relations between the UAVs&#39; gains, which, if satisfied, allows us to decompose each of those motions into two cascaded motions; the latter relations between the UAVs&#39; gains are found so as to counteract the system asymmetries, such as the different cable lengths and the different UAVs&#39; weights. Finally, we provide conditions, based on the system&#39;s physical parameters, that describe good and bad types of asymmetries. We present experiments that demonstrate the stabilization of the bar&#39;s pose.</p>