Lightweight and Compliant Bilateral Teleoperation System with Anthropomorphic Arms for Aerial and Ground Service Operations

This paper presents a bilateral teleoperation sys- tem based on smart servos for the realization of dexterous ma- nipulation tasks with aerial robots or in ground service applica- tions, facilitating the transferability of cognitive capabilities of human workers to robots operating remotely or in high altitude workspaces. The system consists of a pair of lightweight and compliant anthropomorphic dual arm manipulators (LiCAS) in leader-follower configuration. The leader dual arm (LDA) captures the movements of the operator’s arms to obtain the desired joint references, sent to the follower dual arm (FDA) to reproduce in a natural and intuitive way the manipulation task. A model of the smart servos is derived, exploiting the feedback from the FDA actuators to provide the kinesthetic feedback to the LDA, using the pulse width modulation signal (PWM) along with the joint speed to estimate the interaction torque. The mechanical joint compliance of the FDA allows the passive accommodation of the arms to the physical interactions with the manipulated objects or the environment, whereas the very low weight of the arms (1.0 kg LDA, 2.5 kg FDA) and the human-size and human-like kinematics facilitate their use in a wide variety of applications. The performance of the system is evaluated using an industrial task board for benchmarking, and in two illustrative bimanual aerial manipulation tasks.