Dynamic analysis and experiment of a novel ultra-precision compliant linear-motion mechanism

• For the compliant linear-motion mechanism, redundant DOF is diminished and its natural frequency is much higher.
• The good performances including large motion range, reduced parasitic motion, and high natural frequency are achieved simultaneously.
• The interaction between inertia and stiffness is researched.
• The frequency characteristic is evaluated to provide quantitative insight for designers.

The parasitic motion of double parallel four-bar mechanism (PFBM) is diminished at the cost of introducing a non-controllable motion. A family of ultra-precision compliant linear-motion mechanism (CLMM) is therefore proposed. In this paper, the interaction between inertia and stiffness, which is determined by the structure dimensions, is considered. Then the dynamic model is developed using Lagrange equation. Furthermore, the influence of material properties, shape parameters, and geometric parameters on natural frequency is evaluated to provide quantitative insight for designers. The analysis shows that the proposed CLMM has prominent advantage in its frequency characteristics. Finally, the analytic model is verified by finite element analysis (FEA) and experiment. The analytical results are within 6.1% error compared with FEA and within 10.8% error compared with the experimental results.