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In consumer crash tests such as US-NCAP tests, the reported sensor data do not involve rotational motion of the vehicle in many cases. LS-Dyna is a very powerful and popular software to perform vehicle crash simulations however the pre-post processing software LS-PrePost does not provide the determination of overall rotational motion of the vehicle cabin which is designed and expected to remain almost intact under regulatory crash tests. In this study, accelerometer arrays are utilised to obtain the angular acceleration of the vehicle cabin. For this purpose, 3 triaxial accelerometers are used first to obtain the angular acceleration of the vehicle cabin by numerically solving the equations offline; however this solution has some numerical problems.

Secondly, 4 triaxial accelerometers are utilised to obtain the angular acceleration of the vehicle cabin by using a formulation reported in the literature; this procedure provides angular acceleration by solving a linear system of equations. In the crash simulation analysis using LS-PrePost, 4 nodes are selected whose translational accelerations are processed to obtain angular acceleration using this linear system of equations. The results are verified by analysing the full-width rigid barrier impact simulation of a 2010 model Toyota Yaris. In the verification process, 2 nodes are selected on the undeformed sill of the vehicle to obtain the predominant rotation of the vehicle cabin; then cubic splines are fitted to the rotational displacement curve which is then differentiated twice and filtered using SAE J211 standard to obtain the predominant angular acceleration perpendicular to the x-z plane. The result of this approximate method agrees well with the direct calculation of angular acceleration using 4 nodal translational accelerations. The analyses carried out in this study can be a useful guide in extracting crash pulses to be used in simulation studies or sled tests.