Toward Physical Human-Robot Interaction Control with Aerial Manipulators: Compliance, Redundancy Resolution, and Input Limits

In this paper we introduce a comprehensive framework to control an aerial manipulator, i.e., an aerial vehicle with a robotic arm, in physical interaction with a human operator or co-worker. The framework uses an admittance control paradigm in order to attain human ergonomy and safety; an interaction supervisor to automatically shape the compliance based on the interaction regions defined around the human co-worker; a projected gradient redundancy resolution scheme to exploit the multiple degrees of freedom of the aerial robot to accommodate for possible additional secondary tasks; and a quadratic programming optimization-based inner loop to cope with real world input saturation and increase the safety level of the human co-worker. The control framework is demonstrated and validated through numerical simulations with a human-in-the loop.