Smoother Position-Drift Compensation for Time Domain Passivity Approach based Teleoperation
This addresses a specific issue in bilateral teleoperation for robotics and haptics, offering an incremental improvement over existing drift compensation techniques.
The paper tackled the problem of position drift accumulation in Time Domain Passivity Approach (TDPA)-based teleoperation, which can hinder task performance, by proposing a smoother compensation method that maintains transparency and robust stability, with experimental validation showing good position tracking and regular-amplitude forces under delays up to 500 ms.
Despite being one of the most robust methods in bilateral teleoperation, Time Domain Passivity Approach (TDPA) presents the drawback of accumulating position drift between master and slave devices. The lack of position synchronization poses an obstacle to the performance of teleoperation and may prevent the successful accomplishment of such tasks. Several techniques have been developed in order to solve the position-drift problem in TDPA-based teleoperation. However, they either present poor transparency by over-conservatively constraining force feedback or add high impulse-like force signals that can be harmful to the hardware and to the human operator. We propose a new approach to compensate position drift in TDPA-based teleoperation in a smoother way, which keeps the forces within the normal range of the teleoperation task while preserving the level of transparency and the robust stability of energy-based TDPA. We also add a way of tuning the compensator to behave in accordance with the task being performed, whether it requires faster or smoother compensation. The feasibility and performance of the method were experimentally validated. Good position tracking and regular-amplitude forces are demonstrated with up to 500 ms round-trip constant and variable delays for hard-wall contacts.