Design and analytical analysis of a large-range tri-symmetrical 2R1T compliant mechanism

This paper details design, modelling and analysis of a class of compliant mechanisms with tri-symmetrical planar structures, which are able to achieve three large-range out-of-plane motions. Each compliant mechanism, using identical wire beams with square cross sections, consists of three double 2-beam modules in a tri-symmetrical way. Each double 2-beam module has an embedded serial configuration with a common intersection point of beams. Based on assumptions of small deformations, analytical compliance models of a generic mechanism are then obtained to consider all design parameters. Finally, influences of main parameters on the compliances (and therefore degrees of freedom or degrees of constraint) are fully analysed followed by design insights.