Preloading compliant couplings and the applicability of superposition

Simple planar, multi-segmented compliant couplings are used to study the general concepts of preloading and shape changing. This study shows how stiffness or shape is a function of the effective free lengths of supporting struts embedded within the compliant coupling. The concepts of super wrench and super twist are introduced in order to facilitate study. Finally, the superposition principle is thoroughly studied, and its applicability is identified. With emphasis on internal preloading, the study departs from typical compliant mechanism assumptions of no internal preloading, e.g. [1, p. 138]. Results can be extended to the spatial case using screw theory.