In this paper, a particular mechanical servo system is presented based on the design requirement of scanning wafer stage of 0.1μm lithography. In order to achieve high accuracy and high speed, linear motor and voice coil motor is employed to control long stroke motions and short stroke motions, respectively. Considering extraneous forces resident in the system, a composite movement model with disturbing compensation employing an open-closed-loop D-type Iterative Learning Controller(ILC) is then given. The results of actual application demonstrate that the given system with better robustness can enhance the real-time tracing ability and can satisfy high accuracy at high speed along specified trajectories.

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A high sensitivity navigation receiver based on FPGA and DSP was presented in this paper, which performed to mitigate cross correlations between multiple satellite signals. The hardware was consisted of RF parts, FPGA and DSP. The core chips were SPARTAN3 and TMS320VC5402, which were adapted to process navigation data and calculate user position. The RF Front-End received the navigation signal and convert it to IF signal which was transferred to FPGA. The algorithm of acquisition and tracking of navigation signal were implemented with SPARTAN3. A parallel correlator using three local replica C/A code was developed here, which improved the acquiring efficiency. This system calculated the user position by TMS320VC5402.

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An optimised design was carried out based on the original semi-physical simulation system for the main drive chain of a wind turbine. The input of upper computer simulating wind condition, the safety control of electrical signal and vibration signal acquisition module, relay and AC contactor and dual motor control were added. Simultaneously, the simulation schemes of some common faults on the main drive of wind turbines were also designed in order to perform the experimental simulation of the single fault and multi fault. The primary purpose of simulation is to use practical approaches(such as FFT,EMD)to analyze the changes of the fault signals based on the collected electrical signals, and to determine whether there is a fault through comparison and theoretical analysis. In addition, it aimed for verifying the feasibility of electrical signals under multi-fault conditions, and discussing advantages of electrical signals over vibration signals.