The Naturally-Transitioning Rate-to-Force Controller (NTRFC) is presented for teleoperation of manipulators. Our goal is to provide a single controller which handles free motion, constrained motion, and the transition in-between without any artificial changes. In free motion the displacement of the master device (via the human operator’s hand) is proportional to the commanded Cartesian rate of ...

The Naturally-Transitioning Rate-to-Force Controller (NTRFC) is presented for remote teleoperation of manipulators. Our goal is to provide a single controller which handles free motion, constrained motion, and the transition in-between without any artificial changes. In free motion the displacement of the master device (via the human operator’s hand) is proportional to the commanded Cartesian r...

This work presents a re-derivation of relative Jacobian matrix for parallel manipulators, expressed in terms of the individual manipulator Jacobians and multiplied by their corresponding transformation matrices. This is particularly useful when the individual manipulator Jacobians are given, such that one would not need to derive an entirely new expression of a relative Jacobian but will only u...

David Wrench, Rachel Waters, Emanuela Carlotti, Sameena Iqbal, Janet Matthews, Marie Calaminici, John Gribben, T Andrew Lister, Jude Fitzgibbon Centre for Medical Oncology, Barts and the London School of Medicine, London, UK; Centre for Statistics in Medicine, University of Oxford, Oxford, UK; Data Management Unit, Medical Oncology Department, Barts and the London NHS Trust, London, UK; Histopa...

In the literature, conventional 3D inverse dynamic models are limited in three aspects related to inverse dynamic notation, body segment parameters and kinematic formalism. First, conventional notation yields separate computations of the forces and moments with successive coordinate system transformations. Secondly, the way conventional body segment parameters are defined is based on the assump...

Cable-suspended robots and haptics interfaces are appealing because of their structural simplicity, high stiffness, and high exerted wrench-to-weight ratio. A major drawback is that cables cannot push but can only exert tension. Therefore, actuation redundancy is required; even so, certain configurations and wrenches will fail since they would require one or more cables to push. The objective o...

Mobile manipulation is a hot area of study in robotics as it unites the two classes of robots: locomotors and manipulators. An emerging niche in the field of mobile manipulation is aerial mobile manipulation. Although there has been a fair amount of study of free-flying satellites with graspers, the more recent trend has been to outfit UAVs with graspers to assist various manipulation tasks. Wh...