A novel disturbance device for aerial manipulation experiments

In the last decade, UAVs endowed with manipulators have increased in their ability to complete complex tasks such as manipulating doors and drawers. Very recent work also includes tasks with non-constant dynamics such as pushing a cart along a surface with a change in friction coefficient or pulling an electrical plug from a socket. These tasks are hard to design and compare controllers for because their dynamics are complex and they may not behave consistently. This paper proposes a tunable and repeatable mechanism for use in experiments that compare different controller designs. The proposed mechanism, called an overcentre mechanism, can provide a nonlinear resistive force and can be easily modified for different force magnitudes. Additionally, it can be quickly re-oriented to disturb altitude or position channels for vehicles with or without manipulators. This paper experimentally compares three traditional observer designs and a baseline controller in two different operating conditions.