ABSTRACT
Routing flexibility can arise due to machine flexibility and/or sequence flexibility. Machine flexibility occurs when a part operation can be performed on more than one machine, while sequence flexibility occurs when the set of operations specified by a part’s process plan is not completely ordered. Machine flexibility requires some level of resource redundancy and is therefore most likely to be supported in larger systems. On the other hand, sequence flexibility is more a function of part design and process planning and is most useful for complex parts with many required operations. Both types of flexibility have the
potential to generate a combinatorial number of routes. For example, a part with n unordered processing steps and k alternatives at every step can potentially follow n!(kn) routes through the system (the n! due to sequence flexibility, and the kn due to machine flexibility).
