An algorithm that acts as an oracle by estimating the number of sequential orders possible for a set of tasks and precedence constraints is presented. The basic oracle algorithm always completes in low order polynomial time even when there are an exponential number of orders, and it produces an exact answer for graphs with simple folds. The algorithm is applicable to many practical problems in CAPP and should be of value in searching for efficient sequences of operations.>

The automatic assembly planning with fasteners (AAPF) prototype system is described. Given a model of a product to be manufactured, the AAPF system produces a high-level assembly sequence for producing that product. The model is defined in terms of constructive solid-geometry primitives and nut, bolt, and screw fastener primitives. The system works backwards by disassembling the finished product model. Under the assumption that no internal or external forces are present, the reverse of a disassembly sequence is a valid assembly sequence. This assembly planning system pays attention to the individual characteristics of the fasteners to produce a more efficient assembly plan. By paying attention to the type, size, and location of each fastener, the fasteners can be grouped and ordered for assembly (where possible) according to similar fastener type, size, and location. Depending on the factory environment, this can reduce the need for moving subparts from work cell to work cell, retooling time, and the time spent at any given machine or work cell. Several examples, ranging from a simple blocks world model to a mechanical computer mouse, are given, including their run times.>