Modeling, Observing and Controlling a Cable-Suspended Aerial Manipulator as a Constrained System

Kurzfassung

The cable-suspended aerial manipulator is a robot consisting of a platform that is fully actuated with a system of 8 propellers, to which a 7-degrees of freedom manipulator is attached. It can be used for manipulation tasks at locations that are in great height or otherwise difficult to access from the ground. The system can be modeled in different ways, four of which are sketched in this thesis, before their equivalence is demonstrated. In particular, modeling it as a collection of rigid bodies subject to Pfaffian constraints is further developed. Different models of the cable-suspended aerial manipulator providing a variety in complexity and accuracy is presented. Subsequently, experimental data is used to validate two selected models and show their respective benefits and drawbacks. Furthermore, the data is used to identify some parameters defining the system's behavior. The full state of the system can not be measured using proprioceptive sensors. Therefore, an observer is extended to be applicable to the system. It runs on exterioceptive sensors' pose and velocity measurements and provides estimate of the full absolute pose. In addition to the observer, a position controller is proposed. The observer and the controller are extensively analyzed using simulations. Finally, the observers is applied to experimental data to show their applicability to the cable- suspended aerial manipulator.