We consider "swept regions" and "swept hypersurfaces"B in Rn+1 (and especially R3) which are a disjoint union of subspaces t = t or Bt = Bt obtained from a varying family of affine subspaces {t : t }. We concentrate on the case where and B are obtained from a skeletal structure (M, U). This generalizes the Blum medial axis M of a region , which consists of the centers of interior spheres tangent to the boundary B at two or more points, with U denoting the vectors from the centers of the spheres to the points of tangency. We extend methods developed for skeletal structures so they can be deduced from the properties of the individual intersections t or Bt and a relative shape operator Srel, which we introduce to capture changes relative to the varing family {t}. We use these results to deduce modeling properties of the global B in terms of the individual Bt, and determine volumetric properties of regions expressed as global integrals of functions g on in terms o...
James N. Damon