In this paper, a novel XY-dimensional submicropositioner, including mechanism, control, and analysis, is successfully presented. The design of the submicropositioner utilizes a monolithic parallel flexure mechanism with built-in electromagnetic actuators and optical sensors to achieve the object of 3-DOF precise motion. From the provided experimental results, there are several main goals that have been achieved in this paper: (1) to integrate the electromagnetic actuator and the parallel flexure mechanism for planar positioning system; (2) to establish the mathematical modeling; (3) to develop an advanced adaptive sliding-mode controller; and (4) to perform extensive experiments to test the realistic performance.

In this paper, a new planar magnetic levitation (maglev) positioning system is proposed, which is capable of executing dual-axis planar motions purely involving magnetic forces. Functionally, such a mechanism behaves like a planar XY table with micrometer precision. Specifically, in this system, a new structure with an adaptive sliding-mode control (ASMC) algorithm is described, which aims to achieve the following three goals: 1) a large moving range (millimeter level); 2) precise positioning (micrometer level); and 3) fast response. The system consists of a moving carrier platform, six permanent magnets (PMs) attached to the carrier, and six electromagnets mounted on a fixed base. After exploring the characteristics of the magnetic forces between PMs and electromagnets, the general 6-DOF dynamic model of this system is derived and analyzed. Then, because of the naturally unstable behavior inherent in maglev systems, the proposed ASMC guarantees satisfactory performance of the maglev system. Experiments have successfully demonstrated the feasibility and effectiveness of the overall system.

An astigmatic detection system is constructed with a modified digital-versatile-disk optical head. This system, with a detecting spot of $\sim 1\mu \mathrm{m}$ , can simultaneously measure the vertical displacements and two-dimensional angular tilts of micromachined elements. It can detect thermal vibrations of microfabricated cantilevers with noise levels of $1.3\mathrm{pm}{\mathrm{Hz}}^{-1∕2}$ for the linear displacement and of $3.2\mathrm{nrad}{\mathrm{Hz}}^{-1∕2}$ for angular displacements over a frequency range from $1\text{to}800\mathrm{kHz}$ . The detecting frequency can even reach beyond $100\mathrm{MHz}$ if high-speed electronic devices are adopted. Further optimization of the system will broaden its applications in diverse technological fields.

Here we demonstrate that an astigmatic detection system (ADS), constructed with a modified digital-versatile-disk (DVD) optical head, can achieve real-time measurement of a linear displacement and two-dimensional (2D) tilt angles with a high sensitivity. An atomic force microscope (AFM), using our detection system to sense the deflection of microfabricated cantilevers, can resolve single atomic steps on graphite surfaces with a noise level less than 0.04 nm in topographic images. This astigmatic detection system can even detect mechanical resonances due to thermal vibrations of microfabricated cantilevers. The high sensitivity, small detecting size and high bandwidth of this detection system is suitable for dynamic characterization of elements in micromachined components. Further optimization of the system will promise many other applications in diverse technological fields.