Synthetic Environments as design tool - A case study

Successful product design requires intensive communication between all stakeholders of the product or service in the very beginning of the development process. In this stage of the development, often communication is inefficient due to the absence of a prototype. We propose the use of a synthetic environment as a methodology and tool to support communication about a concept design among stakeholders; e.g., designers, end-users, and manufacturers. A case study with industrial partners revealed that a low-cost, easy accessible setup, consisting of haptic and visual simulation only, was sufficient for a realistic evaluation of a product and to provide meaningful information to improve its design

Strong Decays of Strange Quarkonia

In this paper we evaluate strong decay amplitudes and partial widths of strange mesons (strangeonia and kaonia) in the 3P0 decay model. We give numerical results for all energetically allowed open-flavor two-body decay modes of all nsbar and ssbar strange mesons in the 1S, 2S, 3S, 1P, 2P, 1D and 1F multiplets, comprising strong decays of a total of 43 resonances into 525 two-body modes, with 891 numerically evaluated amplitudes. This set of resonances includes all strange qqbar states with allowed strong decays expected in the quark model up to ca. 2.2 GeV. We use standard nonrelativistic quark model SHO wavefunctions to evaluate these amplitudes, and quote numerical results for all amplitudes present in each decay mode. We also discuss the status of the associated experimental candidates, and note which states and decay modes would be especially interesting for future experimental study at hadronic, e+e- and photoproduction facilities. These results should also be useful in distinguishing conventional quark model mesons from exotica such as glueballs and hybrids through their strong decays.Comment: 69 pages, 5 figures, 39 table

SPECTRAL OPERATORS FOR THE MANIPULATION OF POINT SAMPLED GEOMETRY

ABSTRACT: In recent years, research on simple geometric primitive-based modeling techniques has attracted more and more attention from researchers worldwide. Point sampled geometry with the simplest form of representation is capable to provide the most flexible shape descriptions. It becomes, therefore, the hot spot in the study of shape modeling. However, interactive modification of the point cloud is a tedious work. In this paper, we present methods for the manipulation of the point-sampled geometry by spectral-based operators, with emphasis on point-set composition and displacement map. Some synthesized point-set models are provided to demonstrate the effectiveness of the proposed approach

Abstract

This paper describes the theory and implications of a discrete mechanics model for deformable bodies, incorporating behavior such as motion, collision, deformation, etc. The model is fundamentally based on inter-atomic interaction, and recursively reduces resolution by approximating collections of many high-resolution elements with fewer lower-resolution elements. The model can be viewed as an extended mass-spring model. We begin by examining the domain of conceptual design, and ®nd there is a need for physics based simulation, both for interactive shape modeling and analysis. We then proceed with describing a theoretical base for our model, as well as pragmatic additions. Applications in both interactive physics based shape modeling and analysis are presented. The model is aimed at conceptual mechanical design, rapid prototyping, or similar areas where adherence to physical principles, generality and simplicity are more important than metri

Automatic fitting and control of complex freeform shapes

In many computer graphics and computer-aided design problems, it is very common to find a smooth and well structured surface to fit a set of unstructured 3-dimensional data. Although general approaches of fitting give satisfactory results, the computation time and the complexity often prevent their further developments in more complex cases especially in reusing an existing design. In this paper, for a better control of existing freeform shapes, they are approximated by feature templates, with emphasis on extendable templates. By the advantage of the small number of intrinsic parameters in the feature based deformable templates, fitting procedures are faster and more robust. Three key types of simple freeform templates, the bump, the ridge and the hole, are introduced first. With distance measuring methods, a uniform optimization function is presented to achieve automatic feature recognition and fitting. By introducing the extendable template, the hole and the ridge template are further developed to match complex freeform shapes. Based on the approximated template, further shape manipulations can be conducted effectively using the shape intrinsic parameters. Numerical experiments are conducted in order to verify the proposed algorithms. It is also described how the matching technique can be applied in computer graphics and computer-aided design applications