Grants and Contributions:

Grant or Award spanning more than one fiscal year. (2017-2018 to 2022-2023)

Bilateral teleoperation and haptic robotic systems enable human operators to manipulate and feel distant and computer simulated objects, respectively. They transfer the dexterity of the human operator to the remote or virtual environment by commanding a real or simulated slave robot to follow the user-commanded motion of a master robot. They convey the feel of the manipulation by applying the interaction forces between the slave and the environment to the operator. Existing applications of teleoperation and haptic systems include space payload manipulation, minimally invasive surgery and virtual reality-based training, with Canada at the forefront of research and development with the Shuttle Remote Manipulator System, also known as Canadarm, and the NeuroArm surgical telerobotic system. Upcoming applications range from telesurgery and physical telerehabilitation to marine oil and gas services, to space and underwater assembly and construction, to subsea and terrestrial explosive device mitigation and to nuclear decommissioning. They require multiple slaves to work together and to communicate to their masters over links with time-varying delays. Time-varying delays pose significant threats to existing cooperative teleoperation and haptic systems. Thus, this application focuses on new control methodologies that will enable cooperation with realistic force feedback among teleoperation and haptic systems with time-varying delays.

Specifically, this proposal is to develop decentralized control strategies congruent with the modelling of networked teleoperator systems as port-Hamiltonian systems on graphs. The guiding philosophy is to assemble a cooperative system from subsystems whose dynamics have been shaped as passive port-Hamiltonians through local feedback and to thwart energy production and dissipation at interconnections. A key innovation will be to encode the time-varying communication delays in graph nodes and to shape their energetic behaviour to match that of certain desirable passive dynamics. An important anticipated outcome is a composability property: the overall cooperative system will inherit passivity, and thus robustness to time-varying delays, from its components. Another innovation will be to shape the dynamics of the time-varying communications in ways that better maintain the physical accuracy of the interaction forces arising during a cooperative manipulation. By enabling cooperation with faithful force feedback across distance, composability will facilitate the deployment of teleoperation and haptic systems to remote and virtual manipulations that demands the combined dexterity of multiple simultaneous operators.