Page 16 - Modular design for machine tools

xiv Terminology and Abbreviations

deployment over 70 years afterward, various terms were used to
represent the modular design, although the essential features within the
concept and method have remained the same. For example, U.S. engineers
used the term unit construction principle before World War II.
Importantly, the term BBS was duly replaced with modular design by
Prof. Koenigsberger himself around 1967, when he served at the
University of Manchester Institute of Science and Technology. On that
occasion, the NC machine tool became accidentally thrived. We may
guess that he proposed this new term to emphasize the user-oriented
aspect of the BBS. Up to today, the modular design has encompassed its
sphere to a various extent, ranging from the production system and
machine tool, through the software and cutting tool, to other products,
although remaining its major application area within the structural
design of machine tools. In due course, machine tool engineers and
related people have been familiar with this terminology. In contrast,
there is now some confusion in the terminology with the advance of the
modular design into some new spheres. Intuitively, this confusion is
caused by the uncertain definition of each key term. In addition, con-
fusion in terminology becomes often more intricate by a new proposal,
which has not been reviewed the past and present perspectives of the
related subject in five fathom deep.
Professors Koren and Ulsoy have, e.g., asserted the importance of recon-
figurable manufacturing systems in their keynote paper of CIRP [2].
However, it appears that they must refer to the effective application of
the modular design principle to the TL in the 1960s, in which the user
was able to replace some modules within the user’s factory. Regarding
flexible manufacturing in the 1980s and beyond, e.g., expandable FMC
of Hitachi Seiki make and FML (flexible machining line) of Fritz Werner
make, the system and line have, furthermore, enough flexibility that the
user has no need to replace the module within the user’s factory. In
fact, there is obviously a difficulty of distinguishing the technological dif-
ference between the reconfigurability and the flexibility of hierarchical
type according to Heisel and Michaelis [3]. In addition, Koren and Ulsoy
have asserted that a variant of the reconfigurable manufacturing sys-
tems is that of combining the flexibility of the FMS with the high
throughput and low-cost dedicated manufacturing lines. Such a system
has, however, already been established as an FTL (flexible transfer line)-
FMC complex of Toyoda Iron Works make, which can also be regarded
as a variant of modular-configured FMS of hierarchical type. Moreover,
it appears that reconfigurable manufacturing is one of the variants of
agile manufacturing with on-the-spot replacement function of the
module, modular complex, and units of a machine within a system. In
other words, a variant in the proposal of Koren and Ulsoy can be interpreted