Abstract: Combination solving is widely used for and/or/not function trees in conceptual design. However, there exist some serious problems such as enormous solving space and difficult conflict orientation in combination solving. A function family solving method is proposed. At first, the concepts of function families and generalized and/or trees are given. Furthermore, and/or/not function trees are equivalently converted to the generalized and/or trees based on classical propositional logic. At last, the function solving algorithm is realized by obtaining function families. The new method is proved to enhance designers’ work efficiency with an instance.

Key words: computer application, function family solving, classical propositional logic, function tree