Flexible link long reach manipulator with lightweight dual arm: Soft-collision detection, reaction, and obstacle localization

This paper proposes the application of long reach manipulators (LRM) in aerial manipulation, attaching a human size and lightweight dual arm at the tip of a flexible link installed at the base of the aerial platform. This configuration extends the reach and the volume of operation of the manipulator, whose workspace is constrained by the propellers and the landing gear, increasing also safety during the physical interactions on flight between the aerial robot and the environment. The deflection of the flexible link is exploited for collision detection and obstacle localization, allowing also the control of the contact force exerted by the arms. These capabilities are supported by a vision system that measures the deflection at the tip. Undesired oscillations of the link are suppressed generating a coordinated motion with the arms. Experiments in a fixed base test bench are conducted for validating the developed functionalities.