![]() A high precision XY-scanner using double-compound parallelogram line spring flexure hinges, which can achieve millimeter-level working range, is designed in, and its first two resonant frequencies are 22.79 Hz for the x-axis and 27.34 Hz for the y-axis, respectively. For example, a large range XY positioning platform using compound parallelogram flexures (CPFs) can achieve a 10 mm × 10 mm positioning range with high resolution, where the first natural frequency of the platform is only 18 Hz. The parallel kinematic configuration, where the VCMs are mounted to the ground and connected with the positioning platform via complex flexure-based structures, is widely used. However, the platform actuated by the VCMs can hardly adopt serial-kinematic configuration because of the large size of VCMs. Two kinds of the most well-known flexure-based mechanism configurations used in the positioning platform are serial and parallel kinematics. Because the size of the VCM is much larger than that of the PSA actuator, the flexure-based mechanism should be designed carefully to guarantee the positioning range and the resolution of the platform. Ĭombining the VCM with the flexure-based mechanism has been a popular research spot in the design of the large-range positioning platform with high resolution. Meanwhile, flexure-based mechanism is also widely applied in the mechanical design of high-resolution large-range positioning platform due to its advantages of compact structure, small size, and no backlash,. Therefore, VCM is widely used as the actuator of the large-range and high-precision positioning platform. Voice coli motor (VCM), one kind of electromagnetic linear motor, has the advantages of large driving force, large stroke (millimeter level), infinitesimal resolution and large acceleration. Although the stroke can be amplified by using complex flexure-based lever structure, ,, ,, it is still within micron level. The stroke of a PSA is about 0.1% of its own length. With the positioning range increasing from micron level to millimeter level, the traditional two-dimensional positioning platform actuated by PSAs cannot meet the demands of the large range positioning due to stroke limitations of PSAs. Generally, scanners with piezoelectric stack actuators (PSAs) are adopted to achieve high-precision positioning (scanning) in scanning probe microscope (SPM) such as scanning tunneling microscope and atomic force microscope, ,. In recent years, various fields such as precision manufacturing, micro-nano measurement, cell micromanipulation, etc., arouse a growing demand of the two-dimensional high-precision positioning platform with large range. The eigenfrequencies obtained by experiments also indicate that the designed platform is capable of high-speed positioning with large range. ![]() Experimental results of the platform tests demonstrate that the platform can achieve millimeter-level positioning with good decoupling between the two axes. The performances of the platform including positioning range, resonant frequency and safety are analyzed through finite-element analysis. Structural parameters and the arrangement of hinges are precisely designed to guarantee the millimeter-level positioning range within safe levels. In addition, XY decoupling is achieved by adopting a novel decoupling structure. Based on the leaf-type flexure hinges, a novel mechanism called mixed-kinematic mechanism, which combines serial and parallel kinematic mechanism together, is proposed to simplify the mechanical structure of the platform to make it compact. Leaf-type flexure hinges are used to achieve large-range positioning. To overcome these shortcomings, a flexure-based decoupled XY high-precision and large-range positioning platform with simple and compact mechanical structure is proposed in this paper. However, their positioning ranges can only reach a few hundred microns, which cannot meet the demand of large-range imaging, especially for biological samples. Piezoelectric stack actuators with mechanical structure are widely used in scanning probe microscope to achieve high-precision positioning.
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