Enhance Displacement Amplification Ratio of Micro-Gripper Compliant Mechanisms Using Bridge-Type Amplifier Based on Make a Decision Criteria and Grey-Taguchi Method.

Creating a compliant mechanism that has a high displacement amplification ratio, a large workspace, low stress, and a high frequency is difficult. Thus, this paper used SolidWorks to design the gripper mechanisms using the series bridge-type (BT) compliant mechanism. Minitab software was used to create orthogonal arrays for the study. The finite element method (FEM) in ANSYS was used to analyze displacement and equivalent stress of the studying model. The Taguchi method was used to evaluate the influence of design variables. The grey relational analysis (GRA) method with MEREC weighting method was utilized to maximize displacement and minimize principal stress. In this investigation, the designed dimension consisted of the thickness of the flexure hinge (FH) was from 0.2 to 0.4 mm, the length of the FH increased from 3 mm to 4 mm, the distance between the centers of the two FHs changed from 0.8 mm to 1.2 mm depending on each position, and the radius between the rigid link and FHs increased from 0.4 to 0.8 mm. The outcomes of the FEM and analysis of signal-to-noise (S/N) of all of the models showed that the designed dimension had significant influenced on the displacement magnification ratio of the micro-gripper compliant mechanism. With an input displacement of 0.01 mm, the optimal displacement and equivalent stress were obtained at 0.62241 mm and 121.08 MPa, respectively, by the grey relational analysis. The optimal case is the third case, with the thickness of the FH was 0.2 mm, the length of the FH was 3 mm, the distance between the centers of the two flexure hinges was 1.2 mm, and the radius between the rigid link and flexure hinges was 0.8 mm. The make a decision criteria consisted of TOPSIS, SAW, WASPAS, and VIKOR techniques, all demonstrate that the third case was the best.