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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 major challenge in predicting driveline torsionals is the modeling of major energy dissipation mechanisms in the driveline. Primary candidates for such mechanisms are viscous dampers and dry friction (hysteresis) dampers which are specifically included by the designers to disperse the energy of torsional vibrations. The inherent structural and other internal damping in the components of the driveline is small as compared to those of viscous and dry friction dampers. Past attempts to model clutch hysteresis have repeatedly resorted to the classical approach of modeling that has been reported many years ago. However, such an approach is oversimplified and assumes, for instance, that the hysteretic effects are independent of the frequency. In addition, the motion of the damper is assumed to be purely harmonic. Also, such studies rely solely upon the static hysteresis characterization of the elements, particularly within the clutch.

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.

A novel computer simulation program entitled TORAN™ has been developed by the Spicer Clutch Division of Dana Corporation. TORAN™ has been developed for use as an engineering tool for quick and interactive, yet a complete torsional analysis of heavy duty truck drivetrains. This will allow the design and application engineers to examine and predict the behavior of these drivetrains throughout practical ranges of frequencies and torques. TORAN™ is more than just another modification of similar existing programs. The Program, which includes a database of confidential data furnished by drivetrain component and OEM manufacturers and algorithms proprietary to the Spicer Clutch Division. The algorithm accommodates some substantial nonlinearities, such as clutch damper hysteresis and universal joint disturbances. Also included are several new modeling features describing geometrical configuration of axles, torsional properties of tires, etc.