Projects for Pallet Recycling in a Solid Modeling Course

The main objective of the projects in our solid modeling course was to find innovative ways of recycling pallets. Pallets are the single largest consumer of hardwood lumber in the United States. Recovered pallet lumber has been proposed as a potential source of material for value added wood products. This recycling activity creates jobs, decreases the volume of pallets going into landfills, and eases the demand that new pallet manufacture places on timber resources. Recycling is important due to low cost of entry into recycling, and increasing environmental concerns regarding resource use and waste disposal.Cockrell School of Engineerin

Improving the Effectiveness of Integral Property Calculation in a CSG Solid Modeling System by Exploiting Predictability

Integral property calculation is an important application for solid modeling systems. Algorithms for computing integral properties for various solid representation schemes are fairly well known. It is important to deigners and users of solid modeling systems to understand the behavior of such algorithms. Specifically the trade-off between execution time and accuracy is critical to effective use of integral property calculation. The average behavior of two algorithms for Constructive Solid Geometry (CSG) representations is investigated. Experimental results from the PADL-2 solid modeling system show that coarse decompositions can be used to predict execution time and error estimates for finer decompositions. Exploiting this predictability allow effective use of the algorithms in a solid modeling system

SMP: A solid modeling program

A prototype solid modeling program, SMP, developed by CSC for Langley Research Center (LaRC) is documented in this paper. The SMP software is employed by the System and Experiments Branch (SEB) of the Space Systems Division (SSD) for preliminary space station design, but is intended as a general purpose tool. The SMP document provides details concerning: the basic geometric modeling primitives and associated operators, the data representation scheme utilized to structure the geometric model, the available commands for both editing and displaying the solid model, the interactive user interface and the input/output interfaces to external software, and the utility of the package in the LaRC computing environment. The document is sufficiently detailed to serve both as a user's guide and reference manual

Solid Modeling and Stereolithography as a Solid Freeform Fabrication Technique at Texas Instruments Incorporated

Over the past 25 years, the CAE/CAD/CAM industry has developed technological advances that have provided industrial users the ability to increase productivity and decrease the cycle time necessary for product development. These technologies include basic wireframe and surface design, specializedapplication software packages, finite element analysis, numerical control, solid modeling, and rapid prototyping. Each of these technologies plays a significant role in industry today. The Defense Systems & Electronics Group of Texas Instruments currently uses these technologies in the mechanical design engineering process. This paper discusses the two specific technologies of solid modeling and rapid prototyping (specifically stereolithography), including their advantages, benefits, and practical applications within the Texas Instruments Defense Systems & Electronics Group. This paper also discusses the use of stereolithography (SLA) rapid~prototype parts within the solid-mold investment~casting process.Mechanical Engineerin

Computer-Aided Lipid Design: phase equilibrium modeling for product design

The aim of this work is use phase equilibrium modeling as an auxiliary tool for product design, especially for those whose desired final properties are directly related to solid fat content (SFC) and melting behaviour. Solid-liquid equilibrium (SLE) modeling has been implemented for triacylglycerols mixtures, the main components of vegetable oils, a renewable raw-material for a wide variety of products. Excess Gibbs energy models were used to model solid-phases while direct optimization of Gibbs free energy using Generalized Reduced Gradient was performed aiming to compute the number of molecules in each phases at the whole range of melting. As results, a computed phase diagram was compared with experimental data from literature as well as a DSC curve. The model was also used to simulate a four-component DSC curve as a predictive tool

Modeling of the solid rotor induction motor

Conventionally the rotors of cage type induction motors are laminated. There is also the possibility of using a solid rotor made from magnetic steel. This option offers advantages associated with ease of construction and reduced material costs. There are two main versions of solid rotor construction. The simpler version is essentially a steel cylinder without a cage or end-rings. A solid steel rotor with an embedded aluminum or copper cage constitutes the other version. There has been very little published work on the first version and, to the author's knowledge, there has not been anything reported on the second version. In this paper an equivalent circuit model is developed for the solid rotor induction motor. The model allows analysis of both rotor versions. It highlights the operational advantages and disadvantages of solid rotor construction

Design modeling for shape optimization

Some important aspects of design modeling for shape optimization are discussed for both stamped sheet metal components and cast solid components. For stamped components the basis for the modeling approach is a boundary design function. Design parameters control the shape of 2-D regions. For more complex, folded plate components, the 2-D regions can be assembled using translation and rotation operations. The analysis model is automatically created using a mesh generation procedure requiring only boundary data. For less complex solid components, it was found that this approach is not suitable. For these structures, the finite element models are typically created using very sophisticated graphical modeling systems. A new approach which overlays a parameterized surface design model on an existing analysis model is described. To summarize, the future needs for solid shape design is described in terms of an extension of the previously described 2-D capability