Applications of temporal logic to assembly and disassembly sequences

For the manufacture of mechanically assembled products, the importance of the assembly sequence planning phase can not be exaggerated. Contemporary approaches tend to underachieve, in terms of mechanical manipulability, or provide an inadequate reasoning mechanism for analyzing the assembly process. Application for temporal logic to vitiate the affects of this latter inadequacy leads naturally of a system of constraints which sort themselves according to the origins of their corresponding specifications. Those which originate from geometric considerations are referred to as hard constraint specifications and those which originate as a list of preferences of a design engineer are called soft constraint specifications. By 1994, the difficulties associated with proper formulation of appropriate specifications had been recognized, and a decisive attack was began: “It should be point out that it appears difficult to specify a correct and complete set of hard constraint for complex assemblies. This difficulty is regardless of the form of representation.” -Seow and Devanathan [32).; We carry on this attack on the problem of formulating specifications and applying them as follows: (a) We revise some of assembly process axioms of Seow and Devanathan and provide proofs of validity of these revised axioms. (b) We generalize the Seow-Devanathan model to one for mechanically assembled products with any number of parts. (c) We carry over similar techniques, appropriately modified, to disassembly processes, and devise a general disassembly sequence planning system (or model).