ON DECIDING 3D PART DISASSEMBLABILITY AND SURFACE MACHINABILITY

In this paper we consider two manufacturing-related problems: 3D part disassemblability and surface machinability. The former is to find a f easible direction along which a part can be separated from a given 3D assembly, and the latter is to find a feasible direction in which an N C machining tool can approach a given surface. We present a unified fo rmulation of these problems by using a system of linear inequalities. We also show that a feasible direction can be found in O(n) time by tr ansforming the formulation into the 2D linear separability problem, wh ere n is the number of faces. All feasible directions can also be foun d in O(n log n) time. Furthermore, by transforming the formulation int o the smallest enclosing sphere problem, an O(n) time algorithm is pro posed to find the optimal direction, i.e., the direction minimizing th e maximum angle to the normal vectors of 3D surfaces.