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Kinematics and Compliance (K&C) testing is used to evaluate the ride and handling performance of an automobile. During a typical K&C test, the vehicle body is fixed while controlled forces or displacements are applied to the wheels. The results of the test include vehicle suspension parameters, such as toe, camber, etc. Numerical simulations of this test are usually performed using multibody dynamics software that introduces simplifying rigid body assumptions. However, the need for component flexibility in K&C simulation is increasing along with demand for more precise suspension system designs. In this paper, a new methodology for K&C simulation is proposed using Abaqus. First, rigid body suspension mechanism analyses are performed using Abaqus and Adams, and the results are compared. Then a nonlinear Abaqus finite element model, with flexible suspension components and vehicle body, is analyzed and the results are compared with the rigid body suspension analyses.

In this paper, the numerical analysis of a three-point bending test of an aluminum foam sandwich structure is performed with the new extended finite element feature supported by Abaqus 6.9. The sandwich beam consists of two aluminum skins and one aluminum foam core. Three different sets of model dimensions are selected for comparison with the reference results (J. Yu, E. Wang, J. Li, Z. Zheng, “Static and low-velocity impact behavior of sandwich beams with closed-cell aluminum-foam core in three-point bending”, International Journal of Impact Engineering, 35, 2008, pp 885-894). Failure modes in this paper can be categorized into three parts: face yield (FY), indentation (IN), and core shear (CS). Face yield occurs on the surface of the core when the thickness of the skin is small. Indentation and core shear occur if the thickness of the skin is relatively large.

In the current study, thermoforming and compression analysis were carried out for the woven composite egg-box panel with the non-orthogonal constitutive material model, which is proposed by Xue et al (Composites: Part A 34 (2003) 183–193). The material model is implemented in commercial engineering software, LS-DYNA, with user subroutine. Xue et al obtained the nonlinear Young’s modulus and shear modulus from the experiment test, but the constant Young’s modulus and shear modulus for fiber are used in this woven composite egg-panel compression analysis for the convenience. Directional properties in non-orthogonal coordinates are detected using the deformation gradient tensor and the material modulus matrix in local coordinate is updated at each time step. After the implemented non-orthogonal constitutive model was verified by performing bias extension test, the egg-box panel simulation was performed.

In this research, off-road vehicle simulation is performed with tire-soil interaction model. The predictive semi-analytical model, which is originally developed for tire-snow interaction model by Lee [4], is applied as a tire-soil interaction model and is implemented to MSC/ADAMS, commercial multi-body dynamic software. It is applied to simulate the handling maneuver of military vehicle HMMWV. Two cases are simulated with Michigan sandy loam soil property. Each case has two maneuvers, straight-line brake and step steer (J-turn). First, tire-soil interaction model and conventional on-road tire model are simulated on the flat road of the same frictional coefficient. The proposed tire-soil interaction model provided larger force under the same slip. Second, the same maneuvers are performed with real off-road frictional coefficient. The proposed tire-soil model can be validated and the behavior of the off-road vehicle can be identified through two simulation cases.

It is not easy to predict precisely the behavior of the suspension with large lateral compliance, considering only kinematic behavior of the suspension. It is necessary to estimate accurately the tire locus in the development of new car in order to secure the minimal and proper clearance between rear tire and rear wheel house. In this article the 5 link rear suspension with panhard rod was taken into account. At first we studied the kinematic behavior of the suspension in various conditions, for example double bump and roll, and then the lateral load compliance behavior of the suspension was studied. The results of each cases were compared to SPMD(suspension parameter measuring device) data. The compliance behavior was obtained by both the simulation of nonlinear large displacement analysis and the kinematic analysis with bush deformation. From the comparison between two cases we recognized that there are the differences between the analysis results.