Development of a redundant anthropomorphic hydraulically actuated manipulator with a roll-pitch-yaw spherical wrist

The Design of a Chain of Spherical Stephenson Mechanisms for a Gearless Robotic Pitch-Roll Wrist

Although bevel-gear robotic wrists are widely used in industrial manipulators due to their simple kinematics and low manufacturing cost, their gear trains function under rolling and sliding, the latter bringing about noise and vibration. Sliding is inherent to the straight teeth of the bevel gears of these trains. Moreover, unavoidable backlash introduces unmodeled dynamics, which mars robot pe...

Tracking Control of the hydraulically Actuated Flexible Manipulator

Parameter Estimation of a Gearless Pitch-Roll Wrist

The work reported here pertains to the design, modelling and analysis of a testbed for a Gearless Pitch-Roll Wrist (PRW), currently under development at McGill University’s Centre for Intelligent Machines. This work aims at the mechanical-parameter identification of the Spherical Epicyclic Cam Train (SECT) prototype of the PRW. The testbed is constructed and set-up, in order to conduct experime...

Singularity Analysis of a 3-rrrr Redundant Spherical Parallel Manipulator

ABSTRACT Study of parallel manipulators highlights the importance of identifying singular configurations (singularities) during the design, and of avoiding them during the operation; because in these configurations the instantaneous kinematics of the manipulator becomes indeterminate. This paper focuses on the determination of singular configurations of a kinematically redundant 3-RRRR spherica...

Development of a spherical stepper wrist motor

This paper presents the design concept of a new spherical stepper robotic wrist motor capable of three degrees of freedom (DOF) motion in a single joint. The spherical wrist motor has significant potential applications where the demands on wrist torque and workspace are low but high speed manipulation of end-effector orientation is required continuously in all directions. Typical applications a...