Extending surfaces for reverse engineering solid model generation

This paper is concerned with the generation of solid model representations from digitized point data. Parametric spline surfaces are used for representing the faces fitted to the data points. These surfaces need to be extended beyond their initial definition for constructing the B-rep model of the object. An approach based on using the tangent vectors at the edges is employed to extend the surfaces. An error analysis that calculates the amount of error incurred for a fixed extension and the amount of allowable extension for a given error is presented. The extension algorithm is then illustrated with some examples. The approach works for single-patch surfaces only and additional work is needed for multi-patch surfaces. The results presented will enhance the capabilities of modelers that reconstruct solid models from measured point data. (C) 1999 Elsevier Science B.V. All rights reserved.