1.9 MECHATRONIC SYSTEMS
A natural stage in the evolutionary process of modern engineering design is encompassed in the area known as mechatronics[70].The term mechatronicswas coined in
Japan in the 1970s [71–73]. Mechatronics is the synergistic integration of mechanical, electrical, and computer systems and has evolved over the past 30 years, leading
to a new breed of intelligent products. Feedback control is an integral aspect of
20 Chapter 1 Introduction to Control Systems
Computers and
Logic Systems
Software and
Data Acquisition
MECHATRONICS
Control Systems
Physical System
Modeling
Signals and
Systems
Sensors and
Actuators
FIGURE 1.19
The key elements of
mechatronics [70].
modern mechatronic systems. One can understand the extent that mechatronics
reaches into various disciplines by considering the components that make up
mechatronics [74–77]. The key elements of mechatronics are (1) physical systems
modeling, (2) sensors and actuators, (3) signals and systems, (4) computers and logic
systems, and (5) software and data acquisition. Feedback control encompasses aspects of all five key elements of mechatronics, but is associated primarily with the element of signals and systems, as illustrated in Figure 1.19.
Advances in computer hardware and software technology coupled with the desire to increase the performance-to-cost-ratio has revolutionized engineering design. New products are being developed at the intersection of traditional disciplines
of engineering, computer science, and the natural sciences. Advancements in traditional disciplines are fueling the growth of mechatronics systems by providing “enabling technologies.” A critical enabling technology was the microprocessor which
has had a profound effect on the design of consumer products. We should expect
continued advancements in cost effective microprocessors and microcontrollers,
novel sensors and actuators enabled by advancements in applications of microelectromechanical systems (MEMS), advanced control methodologies and realtime programming methods, networking and wireless technologies, and mature
computer-aided engineering (CAE) technologies for advanced system modeling,
virtual prototyping, and testing.The continued rapid development in these areas will
only accelerate the pace of smart (that is, actively controlled) products.
An exciting area of future mechatronic system development in which control
systems will play a significant role is the area of alternative energy production and
usage. Hybrid fuel automobiles and efficient wind power generation are two examples of systems that can benefit from mechatronic design methods. In fact, the
mechatronic design philosophy can be effectively illustrated with the example of the
evolution of the modern automobile [70]. Prior to the 1960s, the radio was the only
Section 1.9 Mechatronic Systems 21
FIGURE 1.20
The hybrid fuel
automobile can be
viewed as a
mechatronic
system. (Used with
permission of
DOE NREL. Credit:
Warren Gretz.)
>
significant electronic device in an automobile. Today, many automobiles have 30–60
microcontrollers, up to 100 electric motors, about 200 pounds of wiring, a multitude
of sensors, and thousands of lines of software code. A modern automobile can no
longer be classified as a strictly mechanical machine—it has been transformed into a
comprehensive mechatronic system.