No abstract

This paper proposes optimization techniques to assist in the design and evaluation of fixtures for holding prismatic workpieces. This formulation of the fixturing design problem takes into account deflection of the workpiece subjected to assembly or machining loads. Using the minimization of the workpiece deflection at selected points as the design criterion, the design problem is determining the positions of the fixture supports. The Finite Element Method is used for calculating deflections that are the basis for the design objective function, and the Broyden-Fletcher-Goldfarb-Shanno optimization algorithm is used to determine the fixture support positions. In this paper the proposed objective function is developed and the method is illustrated with three numerical examples.

Analysis of material removal processes I Warren R. DeVries . p.em . -(Springer texts in mechanical engineering) Includes bibliographical references and index.

No abstract

Tolerance analysis and its impact on design, assembly, and manufacturing cost is the focus of Bjorke's book. It begins with a review of probability models applied to modeling tolerance chains, the main analysis tool. If you have had a course in probability and statistics, the concepts will probably be familiar to you, but if not this may be a difficult book to follow. Topics covered in early chapters are weighted heavily to linearizing and mathematically modeling simple chain links. Methods for determining and modeling process capability, assembly interchangability, and ways to synthesize tolerances based on cost models or other tolerance distribution procedures are covered. Two chapters cover interrelated tolerance chain links by way of examples. I found that these examples concentrated too much on the calculations and not enough on how to set up the equations for the tolerance chains. The procedures to analyze a tolerance chain are implemented as a CAD tool that runs on personal computers, and the last chapter is essentially a short tutorial on this system called TOLTECH. My overall impression of this book is that it meets the author's intended objective, "a reference for manufacturing engineers in industry." It gives a statistical treatment of dimensional tolerancing using the tolerance chain concept. Being able to identify these tolerance chains is the difficult part for the novice and the examples offer no middle ground in terms of complexity. Examples go from four or five design tolerances to 17 in a few pages. For mechanical engineers doing design, assembly, or manufacturing, this book is a reference that belongs with their books on geometric dimensioning and tolerancing, internal design standards, and statistical process control.