Dissanayake, MWMG, Goh, CJ & Phan-Thien, N 1991, 'Time-optimal Trajectories for Robot Manipulators', Robotica, vol. 9, no. 2, pp. 131-138.
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SUMMARYA computational technique for obtaining minimum-time trajectories for robot manipulators is described in this paper. In the analysis, limitations to link movements due to design constraints are taken into consideration. Numerical examples based on a two-link planar robot arm shows the feasibility of the technique proposed. A physical explanation for the general characteristics of the observed trajectories is also presented. The importance of appreciating optimal control issues in designing robot manipulators and in planning robot workstation layouts is emphasised.
Waldron, KJ & Hunt, KH 1991, 'Series-Parallel Dualities in Actively Coordinated Mechanisms', The International Journal of Robotics Research, vol. 10, no. 5, pp. 473-480.
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A deep symmetry between serial chain manipulators and fully parallel systems such as the Stewart platform is dem onstrated. This symmetry is shown to be a result of the well-known duality of motion screw axes and wrenches. The appearance of the inverse of the Jacobian matrix in force decomposition in the same role as the Jacobian in rate decomposition is also a consequence of this same duality and of the reciprocity relationship between the motion screw system and the wrench system of a kine matic joint. A geometric meaning of the columns of the Jacobian is demonstrated. A simple example of the appli cation of the ideas presented here to the understanding of the complex combinations of serial and parallel chains found in vehicle and multifingered hand problems is also presented.
