IMProVe 2011 - Proceedings

Simulation and Experimental Approaches
characterize each element. In numerical models the tappet is represented as constituted
by the tappet and The aim of present work is the containment of the inertia forces, the
stiffness components optimization and the fit tolerances of valve train in internal
combustion engines 4T.
The proposed methodology allows, through the development of a test machine, the
evaluation of axial stiffness of tappet depending on eccentricity of the cam tappet contact,
performing a functional analysis that simulate the behaviour of the system in operational
condition, even if, some adjustment of tolerances of the fit between tappet and his guide,
occurred.
The dynamic study of the valve train, through modern computer codes, is performed by
connecting lumped masses, springs and dampers that characterize each element. In
numerical models the tappet is represented as constituted by the tappet and by the
hydraulic element. Each of these elements is characterized by stiffness and mass. The
structural rigidity of the tappet has, in fact, important effects on the dynamic behaviour of
the entire valve train.
The test machine makes possible the choice of the dimensional and geometrical
tolerances of the fit between tappet and his guide; allows furthermore the evaluation of
errors occurred during construction and integration phase. In addition, the test machine is
also suitable for reverse engineering applications, makes it possible to automatically draw
the cam profile in polar coordinates.
Keywords: Tappet, cam, valve lift, 3D modelling, Reverse engineering.
Corresponding Author: S. Massimo Oliveri
Tel.: +39 095 7382404
Fax.: +39 095 337994
e-mail: moliveri@diim.unict.it
Address: Viale A. Doria, 6 Catania.
An investigation on the validity of 3D clothing simulation
for garment fit evaluation
Y. Y. Wu (a), P. Y. Mok (a), Y. L. Kwok (a), J. T. Fan (a), J. H. Xin (a)
(a) Institute of Textiles and Clothing, The Hong Kong Polytechnic University
Abstract:
Virtual cloth simulation received much attention in the past decade, and the fashion
industry has been attracted to use this newly available tool in actual product development
process to strengthen the collaboration along the supply chain and shorten the product
time to market. This paper serves as an exploratory study to analyse the accuracy of 3D
cloth simulation system so as to examine its validity and effectiveness in garment fit
evaluation. A four-phase methodology is proposed in this paper: 20 types of woven fabrics
are first tested in standard laboratory, and the obtained fabric property data are input to
simulate the results of a flare skirt design. Real sample skirts are produced for comparison.
June 15 th – 17 th , 2011, Venice, Italy
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IMProVe 2011 - Proceedings