Design and Analysis of MEMS based Accelerometer for Automatic Detection of Railway Wheel Flat

Authors: Rajib Ul Alam Uzzal, Ion Stiharu, Waiz Ahmed

Abstract:

This paper presents the modeling of a MEMS based accelerometer in order to detect the presence of a wheel flat in the railway vehicle. A haversine wheel flat is assigned to one wheel of a 5 DOF pitch plane vehicle model, which is coupled to a 3 layer track model. Based on the simulated acceleration response obtained from the vehicle-track model, an accelerometer is designed that meets all the requirements to detect the presence of a wheel flat. The proposed accelerometer can survive in a dynamic shocking environment with acceleration up to ±150g. The parameters of the accelerometer are calculated in order to achieve the required specifications using lumped element approximation and the results are used for initial design layout. A finite element analysis code (COMSOL) is used to perform simulations of the accelerometer under various operating conditions and to determine the optimum configuration. The simulated results are found within about 2% of the calculated values, which indicates the validity of lumped element approach. The stability of the accelerometer is also determined in the desired range of operation including the condition under shock.

Keywords: MEMS accelerometer, Pitch plane vehicle, wheel flat.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1072457

References:

[1] Sun, Y.Q., and Dhanasekar, M., "A dynamic model for the vertical interaction of the rail track and wagon system" International Journal of Solids and Structures 39 (2002) 1337-1359.
[2] Ishida, M., and Ban, T., "Modelling of the wheel flats for track dynamics" XXX Convegno Nazionale AIAS- Alghero (SS), 12-15 September 2001.
[3] Jergeus, J., Odenmarck, C., Lunden, R., Sotkovszki, P., Karlsson, B., and Gullers, P., "Full-scale railway wheel flat experiments" Proceedings of Institution of Mechanical Engineers Volume 213 Part F, 1998,pp1-13.
[4] Zhai, W. M., Cai, C. B., Wang, Q. C., Lu, Z.W., and Wu., X. S., "Dynamic effects of Vehicles on Tracks in the case of raising train speed" Proceedings of the Institution of Mechanical Engineers, Part F, v 215, 2001, p125-135
[5] V. Belotti, F. Crenna, R. C. Michelini, and G. B. Rossi, "Wheel-flat diagnostic tool via wavelet transform" Mechanical Systems and Signal Processing 20 (2006) 1953-1966
[6] D. R. Anderson, "Detecting flat wheels with a Fiber-optic sensor" Proceedings of Joint Rail Conference, April 4-6, 2006, Atlanta, GA, USA
[7] Peter Hesser, Joe Noffsinger, and Tom Shanahan, "Precision Train Inspection Methods - North American Adoption of Global Technology" General Electric Company, 2005.
[8] http://www.freepatentsonline.com/4129276.html
[9] Dong, R.G., "Vertical dynamics of railway vehicle-track system," Ph.D. Thesis, Dept. of Mechanical and Industrial Engineering, Concordia University, Montreal, Canada, 1994.
[10] Zhai, W., and Cai, Z., "Dynamic interaction between a lumped mass vehicle and a discretely supported continuous rail track" Computers and Structures Vol. 63, No. 5, pp. 987-997, 1997.
[11] Yan, W., and Fischer, F.D., "Applicability of the Hertz contact theory to rail-wheel contact problems" Archive of Applied Mechanics 70 (2000) 255-268.
[12] Rajib Ul Alam Uzzal, "Role of Railway Vehicle-Track System and Design Parameters on Flat-Induced Impact Load" M. A. Sc thesis, Dept. of Mechanical & Industrial Engineering, Concordia University, Montreal, Quebec, Canada 2007.
[13] Lonsdale, C., Dedmon, S., and Pilch, J., "Effects of increased gross rail load on 36-inch diameter freight car wheels"availableat www.standardsteel.com/rdpapers/2001
[14] Stephen D. Senturia, "Microsystem Design", Kluwer Academic Publishers, 2001
[15] http://www.ee.ucla.edu/~wu/ee250b/Case%20studyapacitive% 20Accelerometer.pdf