Characterization of spatial parasitic motions of compliant mechanisms induced by manufacturing errors

This paper proposes a theoretical model for characterizing manufacturing error induced spatial parasitic motions (MESPM) of compliant mechanisms (CM), and investigates the inherent statistic features of MESPM using Monte Carlo simulation. It also applies and extends a novel finite beam based matrix modeling (FBMM) method to theoretically derive the elastic deformation behavior of an imperfect flexural linkage (IFL), which is a basic element of a wide spectrum of compliant mechanisms. A case study of a well-known double parallelogram compliant mechanism (DPCM) is also conducted, and the practical parasitic motions of a prototype DPCM are characterized by laser interferometer based measurements.