Packaged piezoelectric ceramic actuators （PPCAs） and compliant mechanisms are attractive for nanopositioning and nanomanipulation due to their ultra- high precision. The way to create and keep a proper and steady co...Packaged piezoelectric ceramic actuators （PPCAs） and compliant mechanisms are attractive for nanopositioning and nanomanipulation due to their ultra- high precision. The way to create and keep a proper and steady connection between both ends of the PPCA and the compliant mechanism is an essential step to achieve such a high accuracy. The connection status affects the initial position of the terminal moving plate, the positioning accuracy and the dynamic performance of the nanoposi- tioning platform, especially during a long-time or high- frequency positioning procedure. This paper presents a novel external preload mechanism and tests it in a 1-degree of freedom （I-DOF） compliant nanopositioning platform. The 1-DOF platform utilizes a parallelogram guiding mechanism and a parallelogram load mechanism to provide a more accurate actual input displacement and output displacement. The proposed stiffness model simulation results verify the and dynamic model of the platform. The values of the preload displacement, actual input displacement and output displacement can be measured by three capacitive sensors during the whole positioning procedure. The test results show the preload characteristics vary with different types or control modes of the PPCA. Some fitting formulas are derived to describe the preload displacement, actual input displacement and output displacement using the nominal elongation signal of the PPCA. With the identification of the preload characteristics, the actual and comprehensive output characteristics of the PPCA can be obtained by the strain gauge sensor （SGS） embedded in the PPCA.展开更多
基金This research was supported by the National Natural Science Foundation of China （Grant No. 91223201）, the Natural Science Foundation of Guangdong Province （Grant No. S2013030013355）, Project GDUPS （2010） and the Fundamental Research Funds for the Central Universities （Grant No. 2012ZP0004）. These supports are greatly acknowl- edged.
文摘Packaged piezoelectric ceramic actuators （PPCAs） and compliant mechanisms are attractive for nanopositioning and nanomanipulation due to their ultra- high precision. The way to create and keep a proper and steady connection between both ends of the PPCA and the compliant mechanism is an essential step to achieve such a high accuracy. The connection status affects the initial position of the terminal moving plate, the positioning accuracy and the dynamic performance of the nanoposi- tioning platform, especially during a long-time or high- frequency positioning procedure. This paper presents a novel external preload mechanism and tests it in a 1-degree of freedom （I-DOF） compliant nanopositioning platform. The 1-DOF platform utilizes a parallelogram guiding mechanism and a parallelogram load mechanism to provide a more accurate actual input displacement and output displacement. The proposed stiffness model simulation results verify the and dynamic model of the platform. The values of the preload displacement, actual input displacement and output displacement can be measured by three capacitive sensors during the whole positioning procedure. The test results show the preload characteristics vary with different types or control modes of the PPCA. Some fitting formulas are derived to describe the preload displacement, actual input displacement and output displacement using the nominal elongation signal of the PPCA. With the identification of the preload characteristics, the actual and comprehensive output characteristics of the PPCA can be obtained by the strain gauge sensor （SGS） embedded in the PPCA.
