Unformatted text preview: ghy and G. K. Knopf sample set is used for minimum deviation zone fitting, using the objective function in Equation (2). 4. SIMULATION An arbitrary B-spline surface created from 16 control points with an overall dimension of 900mm×600mm×200mm is modeled to simulate the inspection process. Systematic machining errors are simulated [ElMaraghy et al., 2004] in order to emulate geometric deviations resulting from machining of the surface, by considering the combination of all independent errors in the elements and linkages of the machine tool using a kinematics approach. The actual independent errors used were measured in a typical vertical 3-axis machine tool [Hocken, 1980]. The non-systematic part of the machining errors are simulated by adding normally distributed error, with a mean equal to zero and standard deviation of 1 µm, to the generated surface in all three X, Y and Z directions. 4.1. Initial sampling A stratified strategy for initial sampling is applied. The surface is divided uniformly into 16...
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- Spring '10
- The Land, ........., Computer-aided design, Joseph K. Davidson, M. GIORDANO