FLEXURAL MECHANISMS FOR HIGH PRECISE SCANNING APPLICATIONS: A REVIEW

In the era of high precision positioning, various mechanisms like piezo based stages, spring loaded systems and ball screw mechanism have been developed till the date to fulfil the need of precise scanning applications. Precision position is important for achieving highly sophisticated manufacturing and measurements. Rigid body mechanism (spring loaded and ball screw) have large range of motion but operating at lower speed, positioning accuracy is also low and they suffer with friction and backlash. Piezo based Nano positioning stages have high speed of operation and high positioning accuracy but it has smaller scanning range. To overcome these issues, researchers are favoring flexural mechanisms which exhibit high speed of operation, large scanning range and a higher degree of positioning accuracy. Flexural mechanisms offer frictionless, backlash free motion to achieve high degree of repeatability and precise control. The current article reviews development of flexural mechanism (both planar and hinge type) by various researchers across the globe. It presents design aspects, structural aspects and application domains of precision flexural mechanisms. The current status of the research in designing flexural mechanisms for high precision applications is also presented. Scope of design and development of flexural mechanisms for various applications are listed at the end of the paper.