Robust Design Of Micro-fluidic Inertial Switch

This paper presents a micro-fluidic inertial switch with varying rectangularcross section, which utilizes the moving mercury droplet in the micro-channel toclose a switch, and overcomes the shortcomings of micro-mechanical switchbased on solid-solid contact, such as contact wear and signal bounce.According to structure and mechanism of micro-fluidic inertial switch withvarying rectangular cross-section, the analytical model of threshold g-value isestablished. Based on the VOF concerning surface tension and contact angleeffects, the transient response process of mercury droplet in the microchannel issimulated, which reflects the threshold characteristics. The results providereference for switch design, and simulation data can be used to identifyanalytical model of threshold.Based on the empirical method of Taguchi robust design, the parametersimportant to the threshold characteristics are optimized in order to reduce thedesign’s sensitivity to manufacturing errors or other disturbances. Therelationship between design parameters and threshold g-values is first acquiredfor identifying analytical model by numerical simulation methods. On thesebases, an approximate linear analytical model is fitted using response surfacemethodology over a small region. Making direct use of the identified thresholdmodel, the robust design of micro-fluidic inertial switch is realized with designperiod shortened greatly.Ultimately, several key design parameters are obtained, which make thethreshold characteristics optimum and robust. Experimental results show that theanalytical model and numerical simulation presented are efficient, and verify thefeasibility of robust design method.