Design and modeling of a novel push - pull type piezomotor with infinite stroke

High resolution and large stroke is a pair of contradiction, while they both are demanded in the nanopositioning operations. In conformity, the PZT actuator could only afford the stroke below 1mm even accompanied by lever-based displacement amplifier, which is far from the request. This paper illustrates a tiny flexure-based push-pull type motor (PPTM) with nanometer resolution and infinite stroke, whose foundation is piezoelectric (PZT) actuator. The PPTM is composed of flexure-based holder and motion-transmitting compliant mechanisms in propose of minimizing the cubage and enhancing the stability by employing parallel piezo actuators. With the function offered by friction between the slide and PPTM, infinite stroke could be accomplished. Besides the synthesis through rigid-body replacement, dynamic modeling based on pseudo-rigid body model (PRBM) is carried out. Ultimately, an adequate control waveform is planned and finite element analysis (FEA) method is put forward to simulate the performances of PPTM.