Liao Haiyang

Vibration-based Piezoelectric Generator and Its Application in the Wireless Sensor Node

The mathematical model of the vibration-based piezoelectric generator with the proof mass supported by a cantilever is established.The formulas of the frequency,the output voltage and the output power are derived.Testing results show that this model is more accurate than Roundys model.According to such characters as large transient power and small average power of the typical wireless sensor node,the power self-regulation circuit of the piezoelectric multi-shaker micro-generator is proposed.When the electricity in the super capacitor of the main circuit is enough to power the wireless sensor node,the main circuit is opened by the ancillary return circuit and the node starts to measure and transfer the results to the monitoring center.The field test on an engine of a ship shows that the vibration-based piezoelectric generator can be used to power a wireless sensor node.

Human's Health Monitoring SYSTEM Based on Wireless Network

This system integrates sensing technology and radio frequency technique together, and puts a new method forward on the acquire of humans health parameters. Base on this method, a portable humans health parameters acquire system with low cost was designed. The precision in body heat measure is plusmn0.5degC and in blood pressure measure is plusmn1mmHg. Within an effective communication distance, the practical rate of inaccuracy of wireless transmission is 0%.

Power Self-Regulation Circuit of Piezoelectric Multi-Shaker Micro-Generator

Based on requirement for power supply of wireless emitting module of machine malfunction vibration monitoring system and characteristic of low power output of micro-generator, a novel power supply manage and control module which controls output power of micro-generator is advanced, and low power consumption self-regulation circuit is designed. Its feasibility has been proved by experiments. Under the condition of resonance frequency 50 Hz and acceleration 0. 15 g ~ 0. 2 g, piezoelectric multi-shaker micro-generator managed by power self-regulation circuit could maintain wireless emitting module of machine malfunction monitoring system to stably work for long time at 3.28 V.

Design of Data Acquisition and Processing System for Mini Raman Spectroscopy

Mini Raman spectroscopy is applied to rapid extraventricular substance identification. Aiming at its outdoor application a particular system design of spectral data acquisition and processing was presented. A novel spectral data acquisition technique with CCD of which the integration time is controllable and self-adjusting was realized. A portable power management design was introduced. ARM and CPLD techniques were combined to implement real-time control and data processing. A program of searching the peak of Raman spectra based on comparison algorithm was given.

Novel Peak-Search Algorithms of Raman Spectrum

It is important to locate Raman characteristic peak in qualitative analysis and quantitative analysis of substance. Because of the insufficiencies of comparison method and derivative, convolution and singularity detection of the discrete wavelet transform are used in the peak-search processing of Raman spectrum. The result of experiment shows that peak position can be located by using the methods above accurately, and the precision of peak-search is improved in qualitative analysis and quantitative analysis of substance.