A Flexure-Based XY Precision Positioning Stage with Integrated Displacement PVDF Sensor

摘要

A piezo-actuated XY precision positioning stage with integrated piezoelectric displacement sensor is developed. The displacement sensing is realized by bonding a semi-rectangular shaped polyvinylidene fluoride (PVDF) film on the surface of the guiding flexible beam. The measuring principle is based on the simple kinematic relationship and the 'clamped-sliding' boundary condition of the guiding flexible beam, both of which are widely available in compliant mechanisms. The sensing concept is experimentally verified with high precision and sensitivity, resulting in a comparative precision with the commercial optical displacement meter but with smaller waveform distortion at high frequencies. The presented precision positioning stage is measured with a maximum stroke range of 138 μm × 138 μm. The feature of the sensing method lies in its very compactness with high precision, fast frequency response, low cost, fine resolution and simplicity, thus opening up interesting opportunities for volume displacement measuring of precision positioning stages or other flexible manipulators with confined interspaces and harsh environments where integrating a bulky transducer is hard.