Authors: Renato Maia Matarazzo Orsino; Tarcisio Antonio Hess Coelho
Addresses: Department of Mechanical Engineering, Polytechnic School, University of São Paulo, Avenue Professor Melo Moraes 2231, Sao Paulo, SP 05508-900, Brazil ' Department of Mechatronics and Mechanical Systems Engineering, Polytechnic School, University of São Paulo, Avenue Professor Melo Moraes 2231, Sao Paulo, SP 05508-900, Brazil
Abstract: Parallel kinematic structures are considered very adequate architectures for positioning and orienting the tools of robotic mechanisms. However, developing dynamic models for this kind of systems is sometimes a difficult task. In fact, the direct application of traditional methods of robotics, for modelling and analysing such systems, usually does not lead to efficient and systematic algorithms. This work addresses this issue: to present a modular approach to generate the dynamic model and through some convenient modifications, how we can make these methods more applicable to parallel structures as well. Kane's formulation to obtain the dynamic equations is shown to be one of the easiest ways to deal with redundant coordinates and kinematic constraints, so that a suitable choice of a set of coordinates allows the remaining of the modelling procedure to be computer aided. The advantages of this approach are discussed in the modelling of a 3-dof parallel asymmetric mechanism.
Keywords: parallel mechanisms; robot manipulators; robot kinematics; robot dynamics; homogeneous transformations; analytical mechanics; Kane; numerical simulation; dynamic modelling; robot modelling; parallel robots; parallel kinematic structures; redundant coordinates; kinematic constraints.
International Journal of Mechanisms and Robotic Systems, 2013 Vol.1 No.1, pp.15 - 34
Received: 04 Apr 2012
Accepted: 04 Apr 2012
Published online: 31 Dec 2012 *