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Unformatted text preview: parameters. 2.2. Revolute surfaces The revolute class of surfaces encompass all feature invariant under coaxial rotation displacement, but not invariant under translation along axis. The datum of the feature is constituted by the axis of the feature, which is unique, and by a point along the axis, that can be chosen between the infinite points of the axis. Our algorithm is composed by two optimization routines, which are executed sequentially in order to find the optimized set of parameters. The first step of the algorithm is the minimization of the mean distance between the measured point set and the axis of the feature, while the second step is the minimization of the vertical distance, measured along the z axis, between the measured points and the nominal surface. For sake of simplicity the axis of the feature is chosen coincident with the z axis. The nearest point to the ith actual measurement mi on the z axis is naturally: ni = [0, 0, nzi, 1]T. Then, the generic objective function, equation (3), becomes for the first step: 2 ⎛ ⎡ Cθ SθSψ SθCψ t...
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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