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545

Product Auto

32. Product Automation

Friedrich Pinnekamp

The combined effects of rapidly growing computa-

tional power, and the shrinking of the associated

hardware in recent decades, mean that almost

all products used in industry have acquired some

form of intelligence, and can perform at least part

of their functions automatically.

The inﬂuence of this development on global

society is breathtaking. Today, only 50 years after

the ﬁrst indication of automation, the life of

individuals and the way industries work has been

transformed fundamentally.

The automation of a product requires the ability

to achieve unsupervised interaction between

the device’s various sensors and actuators, and

ultimately the ability to communicate and interact

with other units.

This chapter gives an overview of the require-

ments to be fulﬁlled in the automation of products,

and gives a ﬂavor of today’s state of the art by

presenting typical examples of automated prod-

ucts from a wide range of industrial applications.

These examples cover automation in instrumenta-

tion, motors, circuit breakers, drives, robots, and

embedded systems.

32.1 Historical Background ........................... 545

32.2 Deﬁnition of Product Automation .......... 546

32.3 The Functions of Product Automation..... 546

32.4 Sensors................................................ 547

32.5 Control Systems .................................... 547

32.6 Actuators ............................................. 548

32.7 Energy Supply ...................................... 548

32.8 Information Exchange

with Other Systems............................... 548

32.9 Elements for Product Automation .......... 548

32.9.1 Sensors and Instrumentation......... 548

32.9.2 Circuit Breakers............................ 550

32.9.3 Motors ........................................ 551

32.9.4Drives ......................................... 552

32.9.5 Robots ........................................ 553

32.10 Embedded Systems ............................... 554

32.11 Summary and Emerging Trends ............. 557

References .................................................. 558

32.1 Historical Background

Some 50years ago the term product automation was

not even known. The door opener to the automation of

individual devices, components or products was a tiny

electronic circuit, commercially introduced by Fairchild

Semiconductors and Texas Instruments in 1961: the mi-

croprocessor.

Already 5 years later the trend towards progressive

miniaturization, known as Moore’s law, was initiated

and is still ongoing.

In the 1970s the development of the microproces-

sors geared up and led to the RISC (reduced instruction

set computer) processors and very-large-scale integra-

tion (VLSI) in the 1980s. In the 1980s the step from 32

to 64bit processors was taken.

In 1992, DEC introduced the Alpha 21064 at

a speed of 200MHz. The superscalar, superpipelined

64bit processor design was pure RISC, but it outper-

formed the other chips and was referred to by DEC as

the world’s fastest processor.

Today in 2007 the ﬂagships of microprocessors are

built in 65nm technology, have about 170 million tran-

sistors, and tact frequencies of 2000MHz.

Part D 32

546 Part D Automation Design: Theory and Methods for Integration

With such a powerful brain embedded in a device,

automation has almost unlimited potential.

The enormous impact of this revolutionary tech-

nical development on society is obvious. It changed

the daily life of almost all people in the world.

The personal computer (PC) is based on micropro-

cessors, transforming the way of working in ofﬁces

and factories fundamentally. Microprocessors crept

into almost all devices and made the use of ma-

chines much more convenient (at least after all the

manuals themselves have developed into embedded

systems).

Production of goods boosted to new productivity

levels with microprocessors and there is hardly a sin-

gle niche in our life that is not covered by automation

devices today.

32.2 Deﬁnition of Product Automation

Product automation is a notation that can easily be

confused with production automation or automation

products,allnamesusedinindustry.Toaddtothe

confusion, the individual terms product and automa-

tion have a wide range of meanings themselves. Before

we discuss product automation itseemstobeap-

propriate to clearly describe what we understand by

this.

Production automation is the automation of indi-

vidual steps or the whole chain of steps necessary to

produce. The otherwise manual part of the manufac-

turing is therefore carried out or supported by tools,

machines or other devices.

Industries that produce such tools or machines call

their devices products. Products used to automate pro-

duction can be called automation products. Examples

are numerical controlledmachines, robots or sorting de-

vices. These automation products serve individual steps

or support the infrastructure ofan automated production

line.

To be able to do this, these products or devices

must possessa certaindegree of automation themselves.

A motor that drives the arm of a robot, for example,

must be able to receive signals for its operation and

must have some mechanism to start its operation on re-

quest. Thus a motor, to use this example, must itself be

automated.

When we talk about product automation we have

in mind the automation of devices that fulﬁll various

tasks in industry, not necessarily only tasks in produc-

tion processes. A device with automation capabilities

can also be used as a stand-alone unit to serve individual

functions.

Thus product automation is the attempt to equip

products with functionality so that they can fulﬁll their

tasks fully or partly in an automated way.

In this chapter we want to describe the state of the

art and the trends in automating products.

The functions required to transform a simple tool,

say a hammer, into an automated product – in this case

it may be a robot executing the same movement with

the hammer as we would do with our arm – are very

different, both in nature and complexity.

From the large variety of combinations of these

functions we select a dozen typical applications or

product examples to give a feeling of the status of im-

plementation of automation on the product level.

Further examples can be found in [32.1]

32.3 The Functions of Product Automation

The hammer mentioned above is a good example of

a whole class of products (or devices) with the task of

providing a mechanical impulse to another object (in

most cases a nail). This hammer is useless if no one is

taking it and using it as a tool.

To make a simple hammer an automated hammer,

we need an additional system that provides at least the

functions a person would apply to the hammer in order

to make it useful.

We have to give the hammer a target (hit that spe-

ciﬁc nail), we need a force (an actuator) to move the

hammer, and we have to control the movement in var-

ious aspects: acceleration, direction, speed, angle of

impact, precision of the path. We have to inform the

Part D 32.3

Product Automation 32.5 Control Systems 547

Fig. 32.1 The functional blocks required for automating

adevice

control system (the brain) that the task is executed and

we have to put the hammer back into a default position

after the hit. In addition, we need an energy source to

provide the power for the operation and we need some

sensors (eyes, ears,ﬁngers) to inform the controlsystem

about the status of the hammer and its position during

the action.

In a more schematic way the requirements for au-

tomation look like the following.

Primary task

of the device

Sensors

Control system

Information exchange

with other systems

Actuators

Energy

32.4 Sensors

To automate a device, sensors are required to inspect the

environment and provide information about the subse-

quent reaction of the device.

It depends very much on the task to be car-

ried out with the product which type of sensor is

Table 32.1 Physical parameters to be measured by a sensor

Mechanical properties Distance, speed, acceleration, position, angle, mass ﬂow, level, tension,

movement, vibration

Thermodynamic properties Temperature, pressure, composition, density, energy content

Electrical properties Voltage, current, phase, frequency, phase angle, conductivity

Magnetic properties Magnetic ﬁeld

Electromagnetic properties Radiation intensity, light ﬂuctuations, parameters of light propagation

Other properties Radioactivity

adequate (see Chap. 20 in this handbook and [32.2,

3]).

Table 32.1 gives an overview on the physical pa-

rameters to be measured by the sensor when speciﬁc

properties are applicable.

32.5 Control Systems

The signals from the sensors, in either analog or digital

form, have to be interpreted and compared with a model

of the device task in order to initiate the actuators. The

control system therefore contains all algorithms to pro-

vide a proper operation of the device.

Simple logical controllers are used for on–off func-

tions. Sequence controllers are used for time-dependent

operations of the devices (Chap. 9 on control theory

and [32.4–6]).

Proportional–integral–derivative (PID) controllers

are widely used for parameter control, and the even

more sophisticated model-basedcontrol systemssee use

in device control. For example, the starter of a motor to

close a valve may need to adjust its current ramp-up

curve according to the behavior of the overall sys-

tem in which this valve and its automated motor are

embedded.

Part D 32.5

548 Part D Automation Design: Theory and Methods for Integration

32.6 Actuators

Actuators are the devices through which a controller

acts on the system. As in the case of sensors, the spe-

ciﬁc type of the actuator depends very much on the

application [32.7,8].

Mechanical movements are introduced by spring

mechanisms, hydraulic and/or pneumatic devices, mag-

netic forces, valves or thermal energy. Changes of

thermodynamic properties are introduced through heat-

ing or cooling or pressure variations, for example.

Electrical properties are modiﬁed by charging or

dischargingcapacitors orapplication ofvoltageand cur-

rent, just to mention a few.

32.7 Energy Supply

Energy is required to perform the primary function of

the device. It can be supplied in various forms such as

mechanical, electrical or thermal.

Energy is also required to operate the sensors, actu-

ators, and control systems as well as the communication

channels within or to the outside of the device.

Energy (in most cases electrical energy) can be sup-

plied from remote sources, either via cables or without

a wired connection (for example, transmitted through

electromagnetic ﬁelds), or taken from device internal

storage systems, mostly batteries (in rare cases also fuel

cells).

In the long term, the energy supply for systems that

must operate in remote locations for long periods with-

out intervention will develop into a design issue – for

example, through suitable storage mechanisms.

32.8 Information Exchange with Other Systems

To operate in an automatic way, a device often has to

communicate with its environment. For stand-alone de-

vices, this information exchange is provided through

sensors that observe the external parameters. In the ma-

jority of cases, however, the automated device must

communicate with peer devices or with a superordinate

control system.

Basic information for the function of the device has

to be transferred and, if necessary, updated. Such up-

dates can affect anything from operating data to the

master program for the operation.

It may be necessary for an operator to communi-

cate with the device, thus a man–machine interface is

required.

Other devices or higher control systems may require

information exchange in both directions, to activate the

device, get a status report or synchronize with other

devices in a larger system.

A language for the communication has to be deﬁned

and here several standards have been developedover the

years as automation was spreading across industry.

32.9 Elements for Product Automation

The overview above covers the broad spectrum of as-

pects and applications in product automation. In the

following, some prominent examples of state-of-the-art

implementation of the related technologies are given.

32.9.1 Sensors and Instrumentation

Instrumentation is a crucial element in product automa-

tion. The information required to effectively automate

a product has to be gathered in an adequate way. The

state of the art in sensor technology shall be demon-

strated with a few examples only, characterizing the

level of technology required in modern sensors.

Figure 32.1 shows both a pressure and a tem-

perature sensor. In both cases the probe itself is the

crucial but is by far a minor part of the whole system.

Most of the technology is located in the electronic part

that serves as data evaluation and signal transmission.

Part D 32.9

Product Automation 32.9 Elements for Product Automation 549

Pressure transmitter for

absolute pressure

a Output and auxiliary power

supply

b Zero/span adjustment

c Microprocessor-supported

electronics

d Measuring mechanism

e O-ring

Pressure transmitter 261

from the 2600T series of

ABB

The high-performance TTF300

temperature transmitter of ABB

Temperature transmitters

TTH300 of ABB with HART

communication

Temperature probes

Fig. 32.1 Examples of pressure and temperature sensors (after [32.9,10])

Signal transmission takes place via a communication

protocol.

A further critical element is the human–machine in-

terface, which is becoming more intuitive in its use. The

user is provided only a few simple buttons to check or

modify the settings of the sensors.

A high degree of automation is put into the

peripheral aspects of the sensors after the primary mea-

surement system of the physical parameters have been

developed to perfection.

Orthogonal linear

light waves

Schematic illustration of ABB's fiber-optic sensor

for high DC currents

Sensor head housing mounted around

current carrying bus bars

Profibus

4–20 mA

0–1 V

Opto-

electronics

module

Interface

AC 800 PEC

controller

Power

link

Δφ

Left and right

circular light

waves

Retarder

Current

conductor

Sensing

fiber cell

Reflector

Fiber

Fig. 32.3 Fiber-optic current sensor (after [32.11])

Other sensors are built on new sensing technol-

ogy, perfecting physical effects such as the inﬂuence of

a magnetic ﬁeld on the polarization of light waves prop-

agating in this ﬁeld. Figure 32.3 shows such a sensor for

measuring the direct-current (DC) in a foundry.

The sensor as such consists of an optical ﬁber

wound around the current-carrying bar. The magnetic

ﬁeld generated by the current inﬂuences the light prop-

agation in the ﬁber, from which the amplitude of the

current can be derived.

Part D 32.9

550 Part D Automation Design: Theory and Methods for Integration

Arrangement of the displacement body in

a paramagnetic oxygen sensor

Planar micro-electromechanical system (MEMS)

sensor chip (inner volume approximately 100 mm

)

Copensation

coil

Magnetic field

concentrator

Magnetic field

concentrator

Displacement

body

Mirror

Light source

Photodetectors

Fig. 32.4 Micro-electromechanical oxygen sensor (after [32.12])

The electronic processing of the transformed light

signal occupies the central part of the sensor.

Making use of micro-electromechanical systems

(MEMS) technology, the sensors themselves become

more accurate and easier to manufacture [32.13,14].

An example of this development towards silicon-

based systems is the oxygen sensor head shown in

Fig.32.4.

Compared with other gases, oxygen shows a high

magnetic susceptibility, and this is used to detect it in

a gas ﬂow. The sensor consists of a displacement body

located in a strong magnetic ﬁeld gradient. The torque

of this body is a measure of the concentration of the

magnetic oxygen gas. With silicon manufacturing tech-

nology these delicate mechanical devices can be cut

out on chips and integrated into the overall measuring

system.

Fig. 32.5 Automated circuit breakers for different power levels

32.9.2 Circuit Breakers

Circuit breakers are devices that connect or discon-

nect electrical energy to a user and, in addition,

interrupt a short-circuit current in case of emergency

(Fig.32.5) [32.15].

While the primary mechanism for this function is

the mechanical movement of metal contacts, modern

versions of this product show a very high degree of

automation.

State-of-the-art circuit breakers therefore have

a quick and user-friendly way of setting trip parameters

– preferably a method that can be instantiated ofﬂine

and before installation of the circuit breaker. In addi-

tion, they offer a complete indication of why a trip

occurs, and a data-logger function to record all electri-

cal quantities surrounding the tripping event. Accessing

Part D 32.9

Product Automation 32.9 Elements for Product Automation 551

this information quickly and from anywhere, without

the need to plug a direct physical connections between

the trip unit and the PC or personal digital assistant

(PDA) are also features of modern products.

An important element in any circuit breaker is a cur-

rent sensor. In low-voltage circuit breakers, which are

ﬁtted with electronic trip units, these sensors are not

only used for current measurement, but they must also

provide sufﬁcient energy to power the electronics.

A commonly used sensor is a Rogowsky coil that

provides a signal proportional to the derivative of the

current – this signal needs to be integrated. This is done

digitally with a powerful digital signal processor (DSP),

which is part of the overall multiprocessor architecture,

and essentially theheart ofthe tripunit. Infact, this DSP

is used to carry out other functions, for example, com-

munications, that in previous designs required separate

hardware components.

The elimination of these hardware components

combined with a simpliﬁed trip unit input stage means

that a single printed circuit board (PCB) is all that is

required for the unit’s electronics. This is a vast im-

provement on previous designs where four PCBs were

needed to provide the same functionality.

The circuit breaker shown in Fig.32.6 also has

an integrated human–machine interface (HMI) [32.15].

A high-deﬁnition, low-power-consuming graphical dis-

play makes data easier to read. And, because of an

energy-storing capacitor, a descriptionof the alarms can

be displayed for up to 48 h without the need for an

auxiliary power supply. Nevertheless, these alarm de-

scriptions are saved and can be viewed long after this

48h periodhas elapsedby simplypoweringthe tripunit.

A wireless link, based on Bluetooth technology,

connects the trip unit to a portable PC, PDA or laptop.

This enables users to operate in a desktop environment

familiar to them. From this environment operators can

Fig. 32.6 HMI of a circuit breaker

use electric network dimensioning support programs to

ensure optimal adjustment of the protection functions.

In addition, users can print reports, save data on differ-

ent media, or send data by e-Mail to other parties from

the comfort of their own desk.

The use of ﬁeldbus plug devices allows a choice of

ﬁeldbus (e.g., DeviceNet or Proﬁbus DP) that best suits

the user’s speciﬁc needs when connecting the circuit

breakers to an overall system.

32.9.3 Motors

Motors are the most common devices in produc-

tion automation, being part of production lines or

of robots [32.16]. The need to automate the motors

themselves is therefore very high, but also motors in

stand-alone application have automation features built

in for various reasons.

To avoid negative inﬂuence on the electrical supply

system when motors are switched on, the most common

automation device is the soft starter: when a certain

motor power output is required, the optimal solution

(depending on the power network conditions and re-

quirements) becomes a frequency converter start, also

called a soft start. This allows the motor to be started

at high torque without causing any voltage drop on the

power network.

The converter brings the motor up to speed. Upon

reaching nominal speed and after being synchronized to

the network, the circuit breaker between the converter

and the power network is opened. The breaker between

the motor and the network is then closed. Finally, the

breaker between the motor and the converter is opened.

The control systems to manage the motor come in

two basic varieties. Closed-loop control systems have

encoders in the motor to report its status. This is used as

feedback information for the control algorithm. Open-

loop systems are simpler because these encoders are

omitted, but at the price of a lower control accuracy.

With model-based control, however, the accuracy of

a closed-loop is achieved without encoders. ABB’s di-

rect torque control technology is an example for this

modern approach: it uses mathematical functions to

predict the motor status. The accuracy and repeatabil-

ity delivered is comparable to closed-loop systems, but

with the added bonus of a higher responsiveness (up to

ten times as fast).

Direct torque control (DTC) is a control method

that gives electronic variable-speed motor controllers

[alternating-current (AC) drives] an excellent torque

response time. For AC induction machines, it deliv-

Part D 32.9

552 Part D Automation Design: Theory and Methods for Integration

Torque reference

controller

Internal torque

reference

Internal flux reference

Torque

comparator

Adaptive

motor

model

Optimum

pulse

selector

ASIC

3 ~

Torque status

Flux status

Motor current DC bus voltage

Actual torque

DC bus

Inverter

Switch positions

Switch position

commands

Mains

Rectifier

Actual flux

Control signals

Flux

comparator

Flux

reference

controller

Torque reference

Speed reference

Actual speed

Flux optimizing

on/off

Flux braking

on/off

Speed controller

+ acceleration compensator

–

DTC core

Fig. 32.7 Block diagram of DTC (after [32.17])

ers levels of performance and responsiveness reaching

the machine’s theoretical limits in terms of torque and

speed control (Fig.32.7).

DTC uses a control algorithm that is implemented

on a microcontroller embedded in the drive. The tech-

nology was ﬁrst used commerciallyin 1995, and rapidly

became the preferred control scheme for AC drives, es-

pecially for demanding or critical applications, where

the quality of the control system could not be compro-

mised.

32.9.4 Drives

In the above example of motor automation, soft starters

for smaller motors are often integrated into the motor

itself.

The control systems to manage larger motors

become large in themselves – like their smaller coun-

terparts, they are equipped with power electronic

components as well as control processors and periph-

eral systems, but the size of these rises with their power

capability.

Such units are called drives. Today drive units can

power motors of up to 50MW. The continuing decrease

in size and increase in power in such units is driven by

improvements in power electronics and microelectron-

ics.

When welook ata drive device as a productin itself,

the automation of this product is mainly by two grow-

ing requirements: a simpliﬁed man–machine interface

and communication issues within a system of which the

drive is part.

Intelligent drives are certain to beneﬁt from the

growth of Ethernet communications by becoming an

integral part of control, maintenance, and monitoring

systems. Decentralized control systems will be created

in which multiple drives share control functions, with

one taking over in the event of a fault or error in another

drive. The advantage of this is that reliance on costly

Fig. 32.8 Assistant control panels allow easy program-

ming of standard drives (after [32.18])

Part D 32.9

Product Automation 32.9 Elements for Product Automation 553

programmable logic controllers (PLC) is greatly re-

duced andautomation reliabilityimproves dramatically.

The modern driveis programmedvia a control panel

that is similar in look, feel, and functionality to a mobile

phone. A large graphical display and soft keys make it

extremely easy to navigate. This detachable, multilin-

gual alphanumeric control panel, as shown in Fig.32.8,

allows access to various assistants and a built-in help

function to guide the user during start-up, maintenance,

and diagnostics. For example, a real-time clock assists

in rapid fault diagnostics. When a fault is detected, a di-

agnostic assistant will suggest ways to ﬁx the problem.

Drive setup and conﬁguration data can be copied from

one motor controller to another to ensure that, in the

event of a drive failure, there isno need to start the setup

process from the beginning.

Today, mid-range drives can store ﬁve times the

amount of information compared with typical drives

from the 1980s. In addition, drives with increased pro-

cessing power and memory enable conﬁgurations that

are better suited to an application.

In industry today, software modiﬁcations are the

most usefuland cost-effectiveway ofmodifying adrive.

This is because developments in software have given

drives increased capability with less hardware; for ex-

ample, a drive controlling a conveyor belt in a biscuit

factory can be programmed to operate in many different

ways, such as starting and stopping at certain intervals

or advancing a certain distance. The same drive used

in a ventilation system can be programmed to maintain

constant air pressure in a ventilation duct.

Software developments are also leading to drives

with adaptive programming.Adaptive programmingen-

ables the user to freely program the drive with a set of

predeﬁned software blocks with predeﬁned functions.

32.9.5 Robots

Robots are the prototype of product automation as they

present the impression of a self-determined machine in

the most visible way.

The classical application of robots is found in car

manufacturing, where hundreds of devices perform

movements, grinding, welding, painting, assembly, and

other operations in the ﬂow production (see Chap.21

and [32.19,20]).

Other applications of robotic support are less well

known but are entering the market on a broad base.

The FlexPicker from ABB (Fig.32.9) is one such

example: It is a parallel kinematics robot that offers

a great combination of speed and ﬂexibility [32.21].

Fig. 32.9 The

FlexPicker robot

achieves accel-

erations of 10g

and handles up

to 120item/min

The gripper can pick items with picking rates exceed-

ing 120 items per minute. The products can be picked

and placed one by one. Since all the motors and gears

are ﬁxed on the base of the robot, the mass of the mov-

ing arms is limited to a few kilograms. This means that

accelerations above 10 g can be achieved. Automation

of this fast movement puts different requirements on the

automation system of the device than, for example, the

slow welding of a car roof.

While the primary automation of the robot move-

ment is fully developed (the world’s ﬁrst electrically

driven robot was introduced as early as 1974), the

Fig. 32.10 The MultiMove function, which is embedded

into the IRC5 software, allows up to four robots and their

work-positioners or other devices to work in full coordina-

tion

Part D 32.9

554 Part D Automation Design: Theory and Methods for Integration

further improvements come, such as in the drives ex-

amples, from better coordination of several robots,

a simpliﬁed man–machine interface, and easier pro-

gramming methods for the robot systems.

The recently launched robot controller IRC5 from

ABB, presenting the ﬁfth generation of robot con-

trollers, introduces MultiMove (Fig.32.10). MultiMove

is a function embedded into the IRC5 software that al-

lows up to four robots and their work-positioners or

other devices to work in full coordination. This ad-

vanced functionality has been made possible by the

processing power and modularity of the IRC5 control

module, which is capable of calculating the paths of up

to 36 servo axes [32.22].

The FlexPendant (Fig.32.11) [32.22] is a handheld

robot–user interface for use with the IRC5 controller.

It is used for manually controlling or programming

a robot, or for making modiﬁcations or changing set-

tings during operation. The FlexPendant can jog a robot

through its program, or jog any of its axes to drive the

robot to a desired position, and save and recall learnt

positions and actions.

The ergonomically designed unit weighs less than

1.3kg. It has alargecolor touchscreen, eightkeys,a joy-

stick, and an emergency stop button. The user-friendly

interface is based on Microsoft’s CE.NET system. It

can display information in 12 languages of which 3

can be made active simultaneously, meaning languages

can be changed during operation. This is useful when

staff from different countries work in the same fac-

Fig. 32.11 Handheld programming

tory. The display can be ﬂipped by 180

◦

to make the

FlexPendant suitable for left- or right-handed opera-

tors. The options can be customized to suit the robot

application.

Programming of robots to fulﬁll their sometimes

quite complicated task requires a lot of time and can

in most cases be done by specialists only. However,

considerable progress has been made by virtual robot

programming that allows ofﬂine programming with

models. Recently these systems can also be directly

connected to the robots, which is especially useful to set

up a new robot installation. Background software pro-

grams and the use of templates signiﬁcantly facilitate

this programming work.

32.10 Embedded Systems

Most of the examples given in Sect.32.9 have the

automation function embedded in the product, mak-

ing embedded system a common feature for product

automation.

Embedded systems are special-purpose computer

systems that are totally integrated and enclosed by the

devices that they serve or control – hence the term

embedded systems. While this is a generally accepted

deﬁnition of embedded systems, it does not give many

clues as to the special characteristics the systems pos-

sess. The use of general-purpose computers, such as

PCs, would be far too costly for the majority of prod-

ucts that incorporate some form of embedded system

technology. A general-purpose solution might also fail

to meet a number of functional or performance require-

ments such as constraints in power consumption, size

limitations, reliability or real-time performance.

Most present product automation could not have

been conceived without embedded system technology.

Examples are distributed control systems (DCS)that

can safely automate and control large and complex in-

dustrial plants, such as oil reﬁneries, power plants, and

paper mills. In the early days of industrial automation,

relay logic was used to perform simple control func-

tions. With the advent of integrated circuits and the ﬁrst

commercial microcontrollers in the 1970s and 1980s,

programmable industrial controllers were introduced to

perform more complex control logic.

Industrial requirements vary enormously from ap-

plication to application, but special industrial require-

ments typically include:

•

Availability and reliability

•

Safety

Part D 32.10