The increasing demand for large-stroke positioning systems with high-precision in applications such as semiconductor manufacturing, optical alignment, and biomedical devices has greatly motivated the development of the large-stroke compliant motion stage. This paper proposes a novel design that employs a symmetrical double parallelogram flexure module (DPFM) to achieve motion decoupling and subsequently minimize parasitic errors. Aluminium 7075-T6 is chosen for its high strength-to-weight ratio, fatigue resistance, and machinability, enabling the compliant motion stage to withstand both dynamic and static loads without compromising performance. Finite element analysis (FEA) results reveals that the design closely matches theoretical model, with an average percentage motion error of 0.956% relative to theoretical calculation. The compliant motion stage achieves a maximum actuation range of ±5 mm on both X and Y direction within elastic-regime of the material, while the averaged parasitic motion detected is 0.148% of the desired motion, which validates its fully decoupled motion. Modal analysis shows that the theoretical natural frequencies of the first two modes are 17.375 Hz, corresponding to motion along the X and Y axes. Compared to the FEA modal simulation result, the mathematical model produces 2.524% and 3.144% difference for the first and second mode respectively, which verifies the symmetric design and dynamic stability. Furthermore, the optimized length-to-thickness ratio provides robust buckling resistance, ensuring reliability under compressive loads. Preliminary fatigue stability is also demonstrated through finite element simulations over 50 loading cycles, showing no observable degradation within the elastic regime.

Keywords: Compliant mechanism, Finite Element Analysis (FEA), Structural design, Large-stroke.