Modularity refers to the scheme by which interfaces shared among components in a
given product architecture are standardized and specified to allow for greater
reusability and commonality sharing of components among product families. The
management of innovation through modular product architecture strategies is gaining
increasing importance for firms, not only in practice but also from a theoretical
perspective. It is argued that the degree of modularity inherent in a given product
architecture is sensitive and highly dependent upon the number of components and the
interface constraints shared among the components, modules, sub-systems, and
systems. This paper applies a mathematical model, termed modularization function,
for analyzing dynamics and the degree of modularity of a given product architecture
by taking into account the following variables: number of components, number of
interfaces, new-to-the-firm component composition, and substitutability factor. The
application of the modularization function is illustrated with two elevator systems
from Schindler Lifts of Switzerland: traction and hydraulic elevators. The
comparative analysis of the elevators captures the sensitivity and dynamics of product
architecture modularity created by three types of components (standard, neutral, and
unique) and two types of interfaces (fundamental and optional)
