This thesis treats different aspects of automotive control-systems and consists of four papers covering different areas in this large field. The first paper presents a 9-degrees-of-freedom dynamic model of a tractorsemitrailer vehicle, aimed at simulation and evaluation of active chassis-systems for stability enhancements. Special focus is put on inclusion of the dynamics of load transfer, whic...

We investigate the cyclic behavior of laminate microstructures in finite-strain crystal plasticity and the resulting stress-strain response, based on a variational, incremental description of the microstructure evolution. The nonconvex free energy density in multiplicative singleand multi-slip plasticity gives rise to the formation of fine-scale deformation structures, experimentally observed a...

In the current work, the mesh free Smoothed Particle Hydrodynamics (SPH) method, was employed to numerically investigate the transient flow of a viscoplastic material. Using this method, large deformation of the sample and its free surface boundary were captured without the cumbersome process of the grid generation. This three-step SPH scheme employs an explicit predictor-corrector technique an...

In this paper the factor of safety (FS) and critical line-segments slip surface obtained by the Alternating Variable Local Gradient (AVLG) optimization method was presented as a new topic in 2D. Results revealed that the percentage of reduction in the FS obtained by switching from a circular shape to line segments was higher with the AVLG method than other methods. The 2D-AVLG optimization meth...

Simple three point bending tests were performed on Ni-Ti wires with three different Af points (1 degree C, 13 degrees C and 34 degrees C) to clarify the relationship between Af temperature and load changes under constant deformation. Each wire was deformed at 37 degrees C and then thermal changes were imposed by temperatures of 2 degrees C or 60 degrees C. The load changes with thermal changes ...

The similarity in implied process zones, based on violations of the plastic yield condition, between state stress at edge an incomplete contact subject to reciprocating shear and tension a crack suffering pure mode II loading are compared. This is done for both small large amounts slip, i.e. when frictional slip region either enveloped by or envelops it. results show that realistic coefficients...

The brittle-viscous transition in the lithosphere occurs a region where many large earthquakes nucleate. To study this transition, we sheared bimineralic aggregates with varying ratio of quartz and potassium feldspar. We deformed samples solid-medium deformation apparatus at temperature, T = 750°C pressure, Pc 800 MPa under either constant displacement rate or load boundary conditions. Under ra...

Abstract Fretting in the partial-slip and gross-slip regimes under a constant normal load is considered. The tangential force—displacement relations for forward backward motions are described based generalized Cattaneo—Mindlin theory of contact Masing’s hypothesis on modelling hysteretic loop. Besides critical force displacement parameters (characterizing triggering sliding), model includes one...

A numerical model replicating the stick-slip contact of two elastically similar materials is presented in this paper. Based on Coulomb's law described partial-slip theory Ciavarella, adopts a complementary condition that facilitates design novel algorithm to separate stick and slip regions. Via comparison between simulation results analytical solutions, developed validated applied study role pl...

in this paper the factor of safety (fs) and critical line-segments slip surface obtained by the alternating variable local gradient (avlg) optimization method was presented as a new topic in 2d. results revealed that the percentage of reduction in the fs obtained by switching from a circular shape to line segments was higher with the avlg method than other methods. the 2d-avlg optimization meth...