On the Evaluation of Force Feedback Augmented Teleoperation of Excavator-like Mobile Manipulators

This paper reports the results of the investigation on the use of force feedback to assist a human operator in the teleoperation of open-pit mining excavators. The proposed force feedback strategy allows object interactions. Also, it enables the operator to sense attractive forces toward the excavation/deposit site as a guidance system, especially useful in precision mining. The methodology was evaluated with multiple experiments to compare the use of haptic feedback and the guidance system. Moreover, a group of volunteers performed the NASA Task Load Index to measure their efforts to teleoperate an integrated off-the-shelf excavator-like mobile robot using different scenarios. Results showed that the force feedback decreases by 8% the power consumption of the excavator, which can represent a significant cost reduction in real applications. Furthermore, the proposed system proves to be a useful tool to the operator allowing task assistance and safety in interaction with obstacles, which can mitigate up to 70% of the stress on the manipulator when there is direct contact with surfaces, e.g., manipulation of rocks and boulders.