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The crash performance of an automobile largely depends on the ability to identity impact damage, maintain the passenger safety through deployment of various safety restraint systems, and steer away the vehicle from impact. So, this work is focused on the impact response of an automobile structure so as to find the location, magnitude of impact and asses the severity of damage. The results of the developed generalized forward plate model compared within 2% for FEM and previous other theoretical approaches. The inverse model compared within 7% for location and reconstructed force. Damage severity assessment is also investigated.

A detailed methodology is presented in this paper for a complete assessment of various forces, torques, and kinematic effects due to universal joint angularities and shaft yoke phasing. A modular approach has been adopted wherein constitutive equations represent each of the key elements of a driveline namely the driveshaft, coupling shaft, universal joint, and the transmission/axle shafts. Concentrated loads are used wherever loads are being transferred between the elements of a driveline. Local matrices are developed for the equilibrium of the respective driveline members. The local matrices are then assembled into a global matrix and solved for the kinematic state of the complete driveline. A 6x15 matrix has been developed to represent a general shaft in the system and a 6x10 matrix has been developed for a universal joint cross. This gives us a complete picture of all the loads on all driveline members.

Active suspension for automobiles involves an active control of wheel motions. This work investigates the possibility of realizing controlled wheel motion for an active suspension using a class of smart materials, namely piezoceramics. The proposed concept deviates significantly from conventional practice of using heavier, hydraulic actuators. Rather than accomplishing the wheel motion using the direct stroke of an actuator, the motion is to be realized by actively modifying the effective stiffness of the suspension system using piezoceramic sensing and actuation. Piezoceramic actuators have been typically waived as totally unacceptable for such large stroke, load carrying applications since these actuators have always been limited to micro-motion ranges. In this research, a strategic combination of elastic and piezoceramic layers is shown to have the potential to meet this challenge.