SYNTHESIZING PRECISION FLEXURES THAT DECOUPLE DISPLACEMENT-BASED ACTUATORS

INTRODUCTION The purpose of this work is to generate a deterministic approach for synthesizing flexures that decouple the actuators of multi-degree of freedom (DOF) precision motion stages. This approach utilizes the geometric shapes of the FACT synthesis approach [1] to help designers rapidly visualize and consider every flexure topology that may be used to decouple any set of displacement-based actuators (e.g., setscrew, piezo, thermal, and magnetostrictive actuators). The ability to correctly synthesize such flexures is important because they (i) improve the controllability of the system’s stage by not allowing the output of one actuator to affect the output of the other actuators, (ii) minimize the stage’s parasitic motion errors by only transmitting the intended motions through the flexures to the stage over the full stroke, and (iii) increase the life of each displacement-based actuator by reducing undesired loads (e.g., shearing, bending, or twisting loads) imposed by one actuator to the other actuators. This work most directly impacts the synthesis of largestroke, low-speed, multi-DOF precision flexure systems that are driven by displacement-based actuators.