Search Results

Various prediction methods have been proposed for evaluating the fatigue life of welded joints by combining finite element analysis (FEA) with an experimental database. However, to obtain more universal and accurate fatigue life predictions, it is necessary to have criteria for making integrated evaluations of the fatigue strength of welded joints. This paper presents a study that focuses on the local cyclic plastic zone size (ω*) as the criterion of fatigue strength and investigates its validity. The definition of ω* was given by the relationship between the stress state at the notch tip and the elastic strain which was defined along the strain-life fatigue curve (ε - N diagram) of a base metal. As a result of using ω*, it was found that an integrated fatigue life prediction was possible to a certain extent for notch and arc-welded joint specimens.

This paper describes a calculating method to predict the quasi-static collapsing behaviors of spot-welded closed-hat section curved beams under axial compression. The overall deformat ions and the local buckling modes of beams were calculated using a geometrical model. Force-displacement relations were predicted by a elastic-plastic structural analysis method using the ‘plastic hinge’ concept. Collapsing tests were made on beams which are differenting section size, rotation angle, and metal sheet thickness. Comparisons between the calculated and experimental results of deformed shapes of beams, the local buckling modes and the force displacement relations are discussed.

The CAD/CAM system, named “SCADEM-2”, in Suzuki Motor Co., Ltd. Motorcycle Engineering Division was developed, based on the old system “SCADEM”. 3D CAD/CAM system “SCADEM-2” is more accessible for operating, more speedy for processing and more complete for generating figures than the old system. Since this system opened in 1987, has been popularly used by most designers of Motorcycle Engineering Division. It's main functions are Design (3D), Drafting (2D), Electrical Schematic, and FEM Processing.

A structural analysis for the connecting rod was performed in consideration of bearing crush, oil clearance and initial deformation of the big end bore caused by tightening force of the rod bolts. This analysis enabled to calculate not only the bearing pressure distribution but also the three-dimensional stress state with accuracy. A new fatigue criterion for multi-axial out-of-phase stress was proposed by using mean stress tensor and alternating stress tensor of complex number in this study. This criterion was developed to improve the classical multi-axial “yield criteria”. This criterion is simple, comprehensive and suitable for the evaluation of three-dimensional FEM results. The connecting rods exhibiting high reliability under severe conditions were investigated through the stress analysis and the new evaluation criterion.

3-point belted occupant impact dynamics in frontal collision has been analyzed using finite element method (FEM) computer simulation models. The results from this simulation were compared with experimental results obtained from dummies on sleds or in small size car frontal crash tests. The correlation between the simulation and the experiments in terms of the head injury criterion (HIC), head acceleration, chest acceleration, and dummy motion and kinematics was relatively good. It was confirmed that dummy impact dynamics was influenced by the structure and the geometrical lay-out of the belt system, the seat belt webbing elongation rate, and the seat cushion hardness. The simulation method and dummy impact dynamics were also used, to a lesser extent, to analyze the performance of 2-point seat belt and air bag systems.

This paper presents the evolution of the unique Japanese mini-car (K class vehicle), starting from the social needs and early legal requirements, and the features of the vehicle combined with prospective subjects to be an international commodity. This paper also describes the body design process of the Suzuki Alto/Fronte to illustrate the design of a modern K class vehicle.