Lightweight and human-size dual arm aerial manipulator

This paper presents the design of a dual-arm aerial manipulator consisting of a multi-rotor platform with an ultra-lightweight (1.8 Kg) human-size dual arm prototype and its control system. Each arm provides three degrees of freedom (DOF) for positioning the end-effector, and two DOF for orientation. As most model-based controllers assume that joint torque feedback is available, a torque estimator for the arms is developed. Note that low cost servos used for building low weight manipulators do not provide any torque feedback or control capability. The redundant DOFs in the dual arm prototype are exploited for generating coordinated motions during contact-less phases in such a way that reaction torques can be partially canceled. Preliminary flight tests have been conducted in outdoors, evaluating the torque compensation capability in test-bench. The influence of the reaction torques exerted by the arms over the UAV controller is also analyzed in simulation.