41.5 Conclusion In order to verify the functionality of the MEMS g-switch accelerometer developed by Raghunathan et al. [13], the experimental technique for the acceleration below 10,000 g was investigated via two methods. The first method was the use of the Hopkinson bar setup. Based on the experimental result, the Hopkinson bar setup is not suitable for acceleration below 10,000 g because the Hopkinson bar setup did not result in the repeatable and accurate acceleration in the controlled fashion. The second approach was the use of drop tower tester. The drop tower tester resulted in the accurate acceleration in the controlled fashion because small change in the independent variable resulted in the predictable change in the resultant acceleration. However, the acceleration only reached about 700 g in the existing setup with the drop height of 50 cm. In order to increase the maximum acceleration values, the aluminum stoppers were used in the experiment. However due to the potential issues with the mechanical vibration resonance of Endevco accelerometer being excited during the impact event, it was not possible to observe the legitimate acceleration values above 700 g. In order to seek the solution to the situation, the future study should incorporate the use of the damped accelerometer to minimize the effect of the resonant frequency. References 1. Hopkinson J (1872) On the rupture of an iron wire by a blow. Original papers by the late John Hopkinson, edited by Bertram Hopkinson, Cambridge University Press, pp 316–320, 1901. Originally published in proceedings of the Manchester Literary and Philosophical Society, XI, pp 40–45 2. Hopkinson B (1913–1914) The effects of the detonation of gun-cotton. The scientific papers of Bertram Hopkinson, collected and arranged by Sir J. Alfred Ewing and Sir Joseph Larmor, Cambridge University Press, pp 461–474, 1921. Originally published in proceedings of North-East Coast Institution of Engineers and Shipbuilders, XXX 3. Kolsky H (1949) An investigation of the mechanical properties of materials at very high rates of loading. Proc R Soc Lond B 62:676–700 4. Kolsky H (1963) Stress waves in solids. Dover, New York 5. Sill R (1984) Testing techniques involved with the development of high shock acceleration sensors. Endevco technical paper, TP284. San Juan Capistrano 6. Ueda K, Umeda A (1993) Characterization of shock accelerometers using Davies bar and strain gages. Exp Mech 33(3):228–233 7. Togami T, Baker W, Forrestal M (1996) A split Hopkinson bar technique to evaluate the performance of accelerometers. J Appl Mech 63(2):353–356 8. Togami T, Bateman V, Brown F (1997) Evaluation of a Hopkinson bar fly-away technique for high amplitude shock accelerometer calibration. In: Conference: 68, shock and vibration symposium, Baltimore 9. Forrestal M, Togami T, Baker W, Frew D (2003) Performance evaluation of accelerometers used for penetration experiments. Exp Mech 43(1):90–96 10. Frew D, Duong H (2009) A modified Hopkinson pressure bar experiment to evaluate a damped piezoresistive MEMS accelerometer. In: SEM proceedings, Albuquerque, New Mexico, USA, pp 1896–1903 11. Foster J, Frew D, Forrestal M, Nishida E, Chen W (2012) Shock testing accelerometers with a Hopkinson pressure bar. Int J Impact Eng 46:56–61 12. Chen W, Song B (2011) Split Hopkinson (Kolsky) bar. Springer, New York, pp 334–344 13. Raghunathan N, Nishida E, Fruehling A, Chen W, Peroulis D (2010) Arrays of silicon cantilevers for detecting high-g rapidly varying acceleration profiles. In: IEEE Sensors, Kona, Hawaii, USA, pp 1203–1206 14. Endevco (2009) Acceleration levels of dropped objects. Technical report, TP321. San Juan Capistrano 15. Tee T, Luan J, Pek E, Lim C, Zhong Z (2004) Novel numerical and experimental analysis of dynamic responses under board level drop test. In: 5th international conference on thermal and mechanical simulation and experiments in micro-electronics and micro-systems, EuroSim E2004, Brussels, Belgium, pp 133–140 16. Douglas S, Al-Bassyiouni M, Dasgupta A (2010) Simulation of drop testing at extremely high accelerations. 11th international conference on thermal, mechanical, and multiphysics simulation and experiments in micro-electronics and micro-systems, EuroSimE2010, Bordeaux, France, pp 1–7 17. Wong E (2005) Dynamics of board-level drop impact. J Elect Pack 127:200–207 18. Wong E, Mai Y (2006) New insights into board level drop impact. Microelectron Reliab 46:930–938 19. Li G, Shemansky F (2000) Drop test and analysis on micro-machined structures. Sensor Actuator 85:280–286 20. Seo S, Oh S, Han S (2011) Virtual drop test methodology for a MEMS-based sensor. Electron Mater Lett 7(2):109–113 21. Yang C, Zhang B, Chen D, Lin L (2010) Drop-shock dynamic analysis of MEMS/package system. In: 23rd international conference on micro electro mechanical systems (MEMS), IEEE, Hong Kong, China, pp 520–523 340 W. Tsutsui et al.
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