FIBERLESS FLEXIBLE MICROACTUATOR DESIGNED BY FINITE-ELEMENT METHOD

The flexible microactuator (FMA) is a new type of pneumatic rubber act uator with 3 degrees of freedom (DOF) developed by one of the authors in 1988. It has been applied to various kinds of miniature robots, To achieve the required motion, conventional FMA's are made of a fiber-re inforced rubber, which makes the fabrication process complicated, The fabrication of FMA's from homogeneous rubber without fiber reinforceme nt is necessary if low-cost manufacture is to become a reality, In thi s paper, a new nonreinforced FMA design is developed using a nonlinear hyperelastic finite-element-method (FEM)-based sensitivity analysis. First, global analyses of FMA deformation are made for a wide range of design variables. This is important, to avoid falling into a local op timization. Next, precise optimization is carried out using a sensitiv ity analysis. Finally, a prototype of the fiberless FMA is fabricated and tested. This process demonstrates the feasibility of the new FMA d esign without fiber reinforcement, both theoretically and experimental ly. This new design is suitable for mass fabrication of FMA's at low c ost.