Page 21 - The Mechatronics Handbook

On the commercial side, driven by cost savings achieved through mass production, automation of
the production process was a high priority beginning in the 1940s. During the 1950s, the invention of
the cam, linkages, and chain drives became the major enabling technologies for the invention of new
products and high-speed precision manufacturing and assembly. Examples include textile and printing
machines, paper converting machinery, and sewing machines. High-volume precision manufacturing
became a reality during this period. The automated paperboard container-manufacturing machine
employs a sheet-fed process wherein the paperboard is cut into a fan shape to form the tapered sidewall,
and wrapped around a mandrel. The seam is then heat sealed and held until cured. Another sheet-fed
source of paperboard is used to cut out the plate to form the bottom of the paperboard container,
formed into a shallow dish through scoring and creasing operations in a die, and assembled to the cup
shell. The lower edge of the cup shell is bent inwards over the edge of the bottom plate sidewall, and
heat-sealed under high pressure to prevent leaks and provide a precisely level edge for standup. The
brim is formed on the top to provide a ring-on-shell structure to provide the stiffness needed for its
functionality. All of these operations are carried out while the work piece undergoes a precision transfer
from one turret to another and is then ejected. The production rate of a typical machine averages over
200 cups per minute. The automated paperboard container manufacturing did not involve any non-
mechanical system except an electric motor for driving the line shaft. These machines are typical of
paper converting and textile machinery and represent automated systems significantly more complex
than their predecessors.
The development of the microprocessor in the late 1960s led to early forms of computer control in
process and product design. Examples include numerically controlled (NC) machines and aircraft control
systems. Yet the manufacturing processes were still entirely mechanical in nature and the automation
and control systems were implemented only as an afterthought. The launch of Sputnik and the advent
of the space age provided yet another impetus to the continued development of controlled mechanical
systems. Missiles and space probes necessitated the development of complex, highly accurate control
systems. Furthermore, the need to minimize satellite mass (that is, to minimize the amount of fuel required
for the mission) while providing accurate control encouraged advancements in the important field of
optimal control. Time domain methods developed by Liapunov, Minorsky, and others, as well as the
theories of optimal control developed by L. S. Pontryagin in the former Soviet Union and R. Bellman in
the United States, were well matched with the increasing availability of high-speed computers and new
programming languages for scientific use.
Advancements in semiconductor and integrated circuits manufacturing led to the development of a
new class of products that incorporated mechanical and electronics in the system and required the two
together for their functionality. The term mechatronics was introduced by Yasakawa Electric in 1969 to
represent such systems. Yasakawa was granted a trademark in 1972, but after widespread usage of the
term, released its trademark rights in 1982 [1–3]. Initially, mechatronics referred to systems with only
mechanical systems and electrical components—no computation was involved. Examples of such systems
include the automatic sliding door, vending machines, and garage door openers.
In the late 1970s, the Japan Society for the Promotion of Machine Industry (JSPMI) classified mecha-
tronics products into four categories [1]:
1. Class I: Primarily mechanical products with electronics incorporated to enhance functionality.
Examples include numerically controlled machine tools and variable speed drives in manufactur-
ing machines.
2. Class II: Traditional mechanical systems with significantly updated internal devices incorporating
electronics. The external user interfaces are unaltered. Examples include the modern sewing
machine and automated manufacturing systems.
3. Class III: Systems that retain the functionality of the traditional mechanical system, but the internal
mechanisms are replaced by electronics. An example is the digital watch.
4. Class IV: Products designed with mechanical and electronic technologies through synergistic
integration. Examples include photocopiers, intelligent washers and dryers, rice cookers, and
automatic ovens.

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