SYNTHESIS OF WATT 6-LINK MECHANISM FOR MANIPULATION ACTION IN RELATIVE SPACE

A method for dimensional synthesis of symmetrical six-link Watt's mech anism is presented. The method is based on Chebyshev's best approximat ion theory. The dimensions of the links are determined by partial synt hesis, which involves independent solutions for the crank, and the two dyads. The synthesis problem requires a path generator, since the poi nt of interest moves along a symmetrical trajectory with given symmetr ically changing velocity, as well as a necessary symmetrical orientati on of the output link. In order to satisfy the conditions of the symme try, a special topology (e.g. the Galloway's basic four-bar mechanism) is chosen. The method provides possibilities for pre-estimation of th e structural error. (C) 1997 Elsevier Science Ltd.