A general nonlinear mechanical model based on special-shaped mechanism

Abstract

Nonlinear systems exist widely in nature, however, how to construct systems with accurate expected non-linearity artificially is still a problem, which greatly limits their experimental study and engineering application. In this paper, we present a general nonlinear mechanical model (GNMM) based on special-shaped cam-spring mechanism (SCSM). GNMM consists of a mass, a roller, a track and a novel general spring model (GSM). Firstly, the equation of motion is derived and compared with that of SCSM. Then, the roller trajectory functions for arbitrary given continuous force are derived. Finally, Duffing system with softening non-linearity is constructed as a design example. The results presented herein show that GNMM has a more general restoring force than SCSM, and prove that there are at least six independent mechanical configurations for a given nonlinear system with continuous restoring force.