TABLE OF CONTENTS The customer looks at the gap. But it s an empty space and we don t assign anyone to manage empty spaces.
This chapter begins the first major part of the book. This section, Chapters 2 8, deals with design principles for assemblies. We will approach this in two stages. In the first stage we will deal with products as assemblies of parts, showing how to express top-level requirements in terms of relationships between parts and representing those relationships in a computer. Then we will present a method for creating nominal assembly designs (that is, designs that are assumed free of variation) that meet several rigorous criteria for correctness. Methods for analyzing the effects of variation will be added to the nominal design method in a mathematically consistent way.
Following emerging industry practice, we will refer to critical assembly-level properties of the product as key characteristics (KCs). In different companies, significant characteristics, key product characteristics, functionally important topics, critical-to-function, and critical to quality are all the same thing.
This chapter provides the motivation for KCs and gives a number of examples. As explained in Section 2.E, KCs are intimately related to tolerances and variation. However, before we can deal with tolerances in a systematic way, we need to deal with several other issues. Thus a discussion of tolerances and variation is deferred until Chapters 5 and 6.
Chapter 3 presents the mathematics needed to represent the position and orientation of parts relative to each other in space, as well as how...
