Unformatted text preview: ed by each part on assembly. In the misalignment covariance matrix Σδ the diagonal terms are the variance of the variation at each point
0 and the off-diagonal terms are a measure of the interaction between the variations at two points. The off-diagonal terms are obtained using part data or a covariance model that accounts for part surface variation. Because Σδ is affected only by geometric variation,
0 it is called the geometric covariance. The methods used to model the geometric covariance are presented later in this work. When two compliant parts are joined together and released, the joint moves to a force equilibrium position (see Fig 1). To find the mean and covariance of the equilibrium position for each part a stochastic finite element method (SFEM) is used, as shown in [Tonks and Chase, 2004]. This problem varies from typical SFEM, because the displacements applied to assemble the model are analyzed rather than an external load applied to a fully assembled model. Various SFEM methods...
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This note was uploaded on 08/03/2010 for the course DD 1234 taught by Professor Zczxc during the Spring '10 term at Magnolia Bible.
- Spring '10
- The Land