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Engineering Writing
by Design
Engineering Writing
by Design
Creating Formal Documents of
Lasting Value
Second Edition
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Sapere aude.
Contents
Preface ix
Authors xi
1 Introduction 1
1.1 Why Bother? . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Think, Then Write, Like an Engineer . . . . . . . . . . . . . 1
1.3 Quick Review of Some Design Concepts . . . . . . . . . . . . 3
1.4 Chapter Recap . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.5 Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
vii
viii Contents
Index 233
Preface
ix
x Preface
Michael J. Cloud was awarded a BS, MS, and PhD from Michigan State
University, all in electrical engineering. He has been a faculty member in the
Department of Electrical and Computer Engineering at Lawrence Technolog
ical University since 1987, and currently holds the rank of associate professor.
Dr Cloud has coauthored thirteen other books, mostly in engineering mathe
matics. He is a senior member of the IEEE.
xi
To the Reader
This is a book on technical writing for engineers. There are numerous books
on technical writing — some new, some very old. Many take hundreds of pages
to cover grammar, page layout, the forms of various types of technical docu
ments (letters, memos, reports, abstracts, papers, book chapters, laboratory
notebooks), conventions for composing visual aids (figures, tables, graphs,
charts), and so on. We haven’t tried to write such a book. In fact, nothing
about this book is comprehensive.
We have two goals for this book. The first is to convince you that to write
like an engineer, you must think like an engineer. The second is to provide
you with a book that is easy, fast reading and strikes at the core of what
you should know about engineering writing in order to do a good job. We’re
sure you’re busy and we recognize that technical writing may not be your
top priority, but we believe that there is a certain irreducible set of tools you
can quickly learn to become an effective writer. Their use can save you time,
energy, and frustration. They could also help you get some appreciation for
your technical ideas.
One of the ironies you’ll notice about this book is that it centers on formal
documents but is not itself a formal document. The chatty style we adopted
(talking about we and you, for instance, and using contractions such as don’t
and shouldn’t ) was intentional. We want the book to be friendly and rapidly
readable. With this in mind, let us begin.
xiii
1
Introduction
1
2 Introduction
We want to tell our readers what, where, when, why, and how. So our writing
should represent our thought. Like it or not, people judge us by the quality
of our writing. We cannot be everywhere, but our writing can be (and, as a
result of the Internet, likely will be). It could surely outlive us, acting as a
helpful resource for — or a perplexing annoyance to — subsequent generations
of engineers. We want our writing to be good.
What counts as “good” writing in an engineering context? This question
will be addressed throughout the book. It is worth stating at the outset,
however, that we will keep the needs and purposes of the reader firmly in
mind at all times. We will have to consider the reader: his or her background,
goals and purposes, etc. We are writing to inform a certain target audience, not
just to fill pages with words, equations, and diagrams. On the other hand, we
are not aiming for “perfection” (whatever that is). We are simply trying to do
a job with our writing and to do it well. Standard engineering design processes
do not produce perfect switches or pulleys, and sound writing processes do
not produce perfect documents. Intelligent compromise is basic to all practical
engineering activity.
Engineers exist under constant pressure to be productive. They’re expected
to tackle large tasks, often with little guidance. A writing project can be such
a task.
Dr. Smythe, Ken’s thesis advisor, reminds Ken that he’s an engineer and
that time is money. The grant under which he’s being supported has dead
lines for certain deliverables, and one of those is a report based on Ken’s
thesis. Writer’s block is not an option. The professor also reminds Ken
that the very word engineer is derived from the Latin word for ingenuity.
This switches Ken into more of an engineering mode: “I have a big prob
lem to solve here. That problem involves writing, but it’s still a problem
and engineers are trained problem solvers. What do I know about problem
solving, in general?” His next thought is “How could I design a document
to solve my problem?”
Quick Review of Some Design Concepts 3
These steps can be adapted to virtually any formal technical writing task.
Choose a solution.
Implement your solution
Generate solutions.
and evaluate.
Needs improvement?
FIGURE 1.1
One visual representation of the typical engineering design process.
4 Introduction
After reviewing the design concepts cited above, Ken responds by drafting
a plan as follows.
1. Understand the goal. Ken must produce a graduate thesis that is
acceptable to his advisor and his examination committee.
2. Do your research. Gather data. Ken must clearly understand the
problem he faces. He must learn what a graduate thesis is. Who is the
typical audience for a thesis? Is there a deadline for his final submission
and defense? Ken must put all of his materials in order. These include
the results of his initial literature search, his theoretical work and pre
dictions, descriptions of his experimental setups and preliminary results,
and his tentative conclusions. He knows that his research may not be
complete; further experiments are needed, and the results of these may
necessitate more theoretical work. However, he was told to begin thinking
about the thesis, so he responds by planning to gather what he currently
has available. Realizing that there are probably format requirements for
something as important as a graduate thesis, Ken decides to seek a list of
official guidelines from his university.
3. Generate solutions. Ken will have to develop a set of alternative ap
proaches to writing his thesis. At this point, a major question is how the
thesis should be organized at the chapter level. Rather than planning to
generate just one possible response to this question, Ken follows the stan
dard design process and plans to generate two possible chapter schemes.
He hopes a conversation with his thesis advisor will assist him in choosing
one of these schemes, combining the strengths of both schemes into a new
scheme, or abandoning both schemes in favor of a third scheme he hadn’t
thought of yet.
4. Choose one solution to pursue. For Ken, this choice will be heavily
influenced by discussion with his advisor — a primary “customer” his final
“design” must satisfy.
5. Implement the chosen solution, evaluate it, and refine it if nec
essary. Ken understands that this is where much of his work will lie. He
will have to write, solicit feedback from others, evaluate their comments,
rewrite, try to obtain feedback again, and so on.
By adapting Figure 1.1 to his purposes, Ken has progressed far beyond
merely getting started — he has generated a roadmap for himself. By following
this map, he will avoid getting lost somewhere in the daunting process that
stretches into the weeks and months ahead. Ken knows that at some point, if
he persists, he will see the light at the end of the tunnel. It will be time to put
the finishing touches on his document and arrange an opportunity to defend
its contents before the graduate committee.
Quick Review of Some Design Concepts 5
As an engineer, you can adapt your writing tasks along these lines.
Whether you’re writing a proposal, a report, or even a doctoral dissertation,
a design-based approach will help you start a project, write more efficiently,
and finish the task faster and with better results. Let’s delve more deeply into
some of the fundamental aspects of the design process.
#1 #2
desired
system
#3 #4
FIGURE 1.2
Notion of top-down design. Left: Top-level view of desired system. Right: De
sired system is decomposed into a number of subsystems, labeled #1 through
#4 here. Each subsystem may be further decomposed until the concrete de
sign stages are reached. This is the analysis phase. In the synthesis phase, the
completed subsystems are assembled into the desired system. The core idea is
divide and conquer.
One might take a desired electrical system and break it down into subsys
tems such as a microcontroller, a sensor, an actuator, and a power supply. The
power supply, in turn, might be decomposed into a rectifier and a filter, and so
on. Lower level subsystems are then designed and assembled into subsystems
at the next higher level until the system is complete. This approach — anal
ysis followed by synthesis — is advocated as an engineering design approach
and clearly applies to the design of large, formal documents.
Some design processes can be viewed as hybrid approaches with both top
down and bottom-up elements. Engineering is about what works. We should
state, however, that a key aspect of both approaches is iterative improvement.
Iterative means repetitive; it refers to an approach where successive attempts
are made, each one building on the previous one. You start with your chosen
solution (recall Figure 1.1) and take successive cuts at improving it until
it meets the standards for completion. Engineering design and the writing of
engineering documents are the same in this respect. An iterative improvement
loop is shown in Figure 1.3. In writing, iterative improvement is called revision.
make an
improvement
stay in
improvement
loop
evaluate satisfied
? no
yes
FIGURE 1.3
Flowchart segment for an iterative improvement loop. In technical writing the
“evaluate” step might be labeled “proofread.”
“downstream” issues. That’s the risk we run with a sequential design ap
proach. Sequential design means that design engineers work first in isolation,
only later getting reactions from the other professionals who will eventually
have a say about (and, possibly, veto power over) the project. What if that
group of engineers had started by forming an integrated design team includ
ing experts in marketing, manufacturing and assembly, service, recycling and
disposal, and so on? Such an approach is often called concurrent design. The
two approaches are contrasted in Figure 1.4.
As a writer, you may not have the luxury of assembling a team of experts to
help with a document. Nonetheless, the idea of getting information and early
feedback certainly applies. If you plan to write a journal paper, for example,
it may be wise to pick a target journal before starting to write. Engineer
ing journals differ in their orientations and formatting requirements. A given
publication may require everything to be written in the third person. Early
awareness of such factors can save much work. You may also seek feedback
early and often, providing drafts of a document to someone in (or close to)
the target audience and asking for reactions. Their suggestions, if addressed
early in the writing process, could prevent headaches later on.
Having completed and proofread a first draft of his chapter on the com
plex experiment, Ken gets feedback from the other students in his group.
Fortunately, one of the students who developed part of Ken’s experimental
8 Introduction
bring more
(a) form initial specialists
design team on board
FIGURE 1.4
Sequential design vs. concurrent design: (a) sequential approach, (b) concur
rent approach. The concurrent approach requires more initial structure but
can prevent downstream conflicts.
1.5 Exercises
1.1. What types of design constraints do engineers face? List as many as you can.
1.2. Pose a simple problem and generate at least three alternative solutions.
1.3. Write a short technical paragraph and have an associate read it. Ask what he
or she got from reading it. Use this feedback to revise your paragraph.
1.4. Todd has reached a frustration point with his master’s thesis. He brought 50
pages of written material to his thesis advisor who sharply rejected it for a number
of reasons. Some pertained to specific technical aspects of the research, some to
formatting issues of which Todd was not previously aware, and some to how the
existing material had been organized into chapters. Todd is disoriented and ready
to give up. What advice would you give him?
1.5. Choose a topic within your area of knowledge and consider how you’d explain
it to a layperson. How would you break it into manageable chunks? Would you have
to further decompose some of these chunks to make them understandable to the
reader?
1.6. Pick an engineering, scientific, or technical journal in your area of interest, and
study its mission statement and formatting requirements.
1.7. Engineering programs in North America are accredited by ABET (the Accred
itation Board for Engineering and Technology, Inc.) What does ABET have to say
about the importance of writing ability for engineering graduates?
1.8. How has globalization affected the need for good, clear writing?
1.9. Explore the ethical codes published by professional societies such as the IEEE
and ASME. Do any of the provisions of these codes carry implications about the
quality of an engineer’s written communications? Specify.
1.10. Name some general issues that are commonly addressed in technical writ
ing. One example is adequate functionality: whether some entity will perform well
10 Introduction
In other words, some body of information currently resides in your mind and
must be made available to the minds of the target readers. There are obviously
two main issues here.
1. How does the information reside in your mind? How did it get there,
and what forms does it take? Which portions of the body of information exist
in your mind as visual impressions (“pictures”), abstract concepts, equations,
quotations from authorities, etc?
2. Who is the target audience? What are the attributes common to those
people at whom you will aim your finished document?
If your knowledge of a topic isn’t clear to you, or if it isn’t clear who you’re
trying to communicate with, your chances of true success with the writing
endeavor will be small. Not convinced? Consider this analogy. An engineer
accepts the task of designing an FM radio but fails to adequately consider
(a) the parts available for building such a radio, or (b) the intended function
of a radio (intercepting radio waves from broadcast stations and converting
the information carried by those waves into human-audible form). Rather, his
approach is to grab whatever parts might be at hand, solder them together
without much of a plan, and see what happens. Surely his chances of coming
11
12 Clearly Understand the Goal
up with a working radio are near zero. No properly trained engineer would
approach technical design in such a way.
Unfortunately, some engineers compose their formal documents in precisely
that fashion. They compile what they hope will be “enough” pages of words,
figures, equations, headings, stock phrases, etc., and send the result out the
door to an unknown — or, at best, ill-considered — readership. Granted, this
may seem an apt response to a truly pressing issue, such as
How can I meet this deadline and therefore keep my job?
But it is an untrained response, and we should not confuse “pressing per
sonal issue” with “engineering goal statement.” To make things worse, poorly
conceived goals can cause problems. When companies rush flawed automotive
designs to market, we see massive and costly product recalls. When gradu
ate students submit unreadable theses, they’re often sent back to square one.
Consider the resulting cost in terms of lost time and energy.
expressing Ampere’s law. It may even take the form of “just words,” although
caution in such cases is warranted (recall the admonition of your college en
gineering instructors, that engineering is about thinking rather than memo
rization).
It is not our desire to embark on an adventure in psychology, delving into
how information might be stored in the human brain. But we cannot afford
to be unaware of how we grasp the essential aspects of our own writing topic
if we hope to make a meaningful connection with our target reader. So we
merely suggest that you, as an author, try to maintain some awareness of the
issue while writing.
Example. Jim is writing a technical report on his latest project. His view
of the final design — for a cell phone circuit — is mainly a visual one: when
he thinks about the circuit, it seems natural to do so in terms of a picture.
Jim therefore decides to introduce his readers to the electrical layout by
way of a photograph paired with a labeled line drawing. The drawing will
call attention to certain key features of the photograph (remember, the
camera captures everything, whether conceptually important for present
purposes or not). After all, it took him months of work to formulate this
layout; could a reader grasp it from a photograph alone? A good drawing
will take effort, and Jim entertains the possibility of omitting it. But he
follows his better judgment and painstakingly constructs a line drawing.
Several years later, while referring to the resulting report as a memory
refresher, Jim is pleasantly surprised when that same line drawing guides
him smoothly through what has become a puzzling photograph. Finding
himself unexpectedly in the position of a target reader for his own report,
he discovers that the document has archival value.
How long the Roman Christians were allowed to bury their dead
where they pleased, and to visit their tombs in peace, we can hardly
say. In Africa there had been a popular outcry against the Christian
cemeteries, and a demand for their destruction, in the beginning of
the third century; and the same thing may have happened in Rome
also at the same or even at an earlier date. The first certain record,
however, of any legal interference with the Roman Catacombs
belongs to a period fifty years later, by which time they must have
been both numerous and extensive; it must also have been very
notorious where they were situated. We have seen how public the
entrance was to the Catacomb of St. Domitilla in the first century,
and there is no reason to suppose that this was an exception to the
general rule. The Cœmeterium Ostrianum, on the Via Nomentana,
was as old, and probably as well known, for it was the place where
St. Peter had baptized; the Catacomb of St. Priscilla, too, of the
noble family of Pudens, on the Via Salara, and several others.
We read of St. Anacletus, who was Bishop of Rome about a.d.
160, that he built some sort of monument over the tomb of St. Peter
on the Vatican, and his predecessors and some few of his
successors till the end of the century were buried in this same place,
juxta corpus Beati Petri, as the old records have it. Around the tomb
of St. Paul, also, on the Via Ostiensis, a cemetery was formed, of
which a few monuments still remain, bearing dates of the first
decade of the second century. Hence a priest, writing in that same
century, calls these tombs of the Apostles “the trophies,” or triumphal
monuments, “of those who had laid the foundation of the Church in
Rome.” About a hundred years later we read of St. Fabian—Pope
a.d. 236-250—that “he caused numerous buildings to be constructed
throughout the cemeteries.” And this expression seems to imply that
the cemeteries were no longer private property (as several of them
undoubtedly were at the first), but belonged to the Church in her
corporate capacity, and were administered, therefore, under the
superintendence of her rulers. We have contemporary evidence that
this was the condition of a cemetery on the Via Appia from the
beginning of the third century, Pope Zephyrinus having set over it his
chief deacon, Callixtus; and the obvious advantages of such an
arrangement may have led to its general, if not universal, adoption.
At any rate, we cannot doubt that “the numerous buildings he caused
to be constructed throughout the cemeteries” were either oratories
for public worship, or chambers for the celebration of the agapæ,
which he caused to be built after the fashion of the scholæ of the
Pagan burial-clubs, in the areæ of cemeteries which had not had
them before; and we can easily understand how this increased
provision of places for assembly had been rendered necessary by
the rapid multiplication of the faithful during the long peace which the
Church had enjoyed since the reign of Caracalla.
At the first beginning of the Church in Rome, the Christians had, of
course, met together only in private houses, “under cover of that
great liberty which invested with a sort of sacred independence the
Roman household;” but as their numbers increased, this could not
have sufficed. Very early in the third century, therefore, and probably
even much earlier, there were places of public Christian worship
within the city; and it seems certain that the faithful were allowed
also to assemble (at least under ordinary circumstances) in the
public areæ of their cemeteries up to the middle of the same century.
The language of Tertullian, complaining that the heathen “had
become acquainted with their days of meeting, and that hence they
were continually besieged, betrayed, and caught unawares in their
most secret congregations,” suggests rather the idea of meetings in
subterranean hiding-places than of public assemblies. But he also
tells us that some congregations used to purchase immunity to
themselves by payment of tribute to the Government, and that for
this purpose they were enrolled on the police registers, where, as he
takes care to remind them, they found themselves in anything but
respectable company. These, of course, must have had public
places of meeting; but under what title they can have met, unless it
was that of burial-clubs, such as were described in our last chapter, it
is not easy to conjecture. They could not be enrolled merely as
professors of the Christian faith; for ever since the first persecution
by Nero, the Roman Government had persistently refused to give
any legal recognition to “the new superstition.” For a while, indeed,
the Jews and Christians had been regarded as professing the same
religion, and this was a great gain to the Christians, for there had
been a decree of Cæsar that the Jews throughout the whole Roman
Empire should be allowed to keep their ancient customs without let
or hindrance. The Jews themselves soon vigorously denounced their
supposed co-religionists, and when Christianity had once
established its independence of Judaism, it fell under the ban of an
illicit religion. Thenceforward, though the Christians were not always
being persecuted, they were always liable to persecution, so that
even when it was forbidden to accuse them, yet, if they were brought
before justice and acknowledged themselves Christians, it was
forbidden to absolve them. This was the state of things under the
reign of Aurelian and Commodus, in the latter half of the second
century, when we read of a certain senator, named Apollonius, that
he was accused of Christianity, and pleading guilty to the charge,
was beheaded, while yet the man who had informed against him was
condemned to death also, but by the more cruel and ignominious
method of breaking on the wheel. The beautiful story of St. Cecilia,
too, belongs (it is now ascertained) to some more active period of
persecution about this same time. The story need not be repeated
here, but one of its details is worth referring to, as it probably gives a
true picture of what was happening not unfrequently in those days,
viz., that some of the clergy lay hid in the Catacombs, and inquirers
after the truth were conducted by trusty guides to their retreat. We
must not suppose, however, that any large number of the faithful
ever took refuge there for any length of time; indeed, such a thing
would have been physically impossible. The Christians assembled
there for purposes of worship when the public exercise of their
religion was interfered with; and then this secrecy, thus cruelly forced
upon them, was cast in their teeth, and they were called “a skulking,
darkness-loving people.”
At length, in the year 253, Valerian published a decree whereby he
sought to close against them even this subterranean retreat; he
forbade them “either to hold assemblies or to enter those places
which they call their cemeteries.” The edict was, of course,
disobeyed, and Pope Sixtus II., with some of his deacons, was
surprised and martyred in the Catacomb of Pretextatus. This
Catacomb was situated in a vineyard on the opposite side of the
road from the Catacomb of St. Callixtus, and perhaps it had been
selected as the place of meeting because it was less known to the
public than that chief of Christian cemeteries. The secret, however,
had been betrayed, and (as we learn from an inscription by Pope
Damasus) the Holy Pontiff was apprehended whilst in the midst of a
religious function. The faithful who were present vied with one
another in offering themselves to martyrdom, in his company at
least, if not in his stead, but only the deacons obtained the coveted
privilege. The Bishop himself was led before the tribunal,
condemned, and then brought back to the scene of his “crime,”
where he received the crown of martyrdom either in his pontifical
chair itself, or at least so near to it that it was sprinkled by his blood.
The charge on which he was condemned was distinctly this, “that he
had set at nought the commands of Valerian.” But in the following
year these commands were revoked, and during the next fifty or sixty
years the Catacombs come before us in successive periods of
Church history as enjoying good or evil fortune according to the
varying fortunes of the Church herself, of which they became a chief
battle-field. If Valerian interdicted them, Gallienus, his son, restored
them; and thus they were tolerated and forbidden, forbidden and
tolerated again, according to the will of the Government, until at last,
before the end of the century, they were confiscated altogether.
More than two centuries had now elapsed since the Catacombs
were begun, and they had attained a degree of development far
beyond anything that could have been anticipated. Divers
modifications also had been gradually introduced in the execution of
the work, and of these it will be worth while to give some account.
We will take the cemetery of St. Callixtus as a specimen; for
although in almost every Catacomb there is some difference in detail
from the rest, caused either by some local peculiarity, or by the mere
taste or caprice of those who made it, yet, in outline at least, the
process of development must have been the same in all. It seems to
have been something of this kind. At first a plot of ground in some
suitable situation was either given by its Christian proprietor, or
acquired by purchase, and secured by all necessary legal formalities
—probably also enclosed by a wall or other fence—as a place of
burial. A plan of excavation was then determined upon, and the work
begun. Whilst as yet the fossors had had no experience of the
consistency of the material in which they were to labour, and whilst
they imagined themselves to be providing for the burial only of a few,
they would naturally work freely and without much regard to
economy of space. But as time went on the necessity for economy
would become apparent; then they had recourse to various devices
for securing it. They lowered the floors both of the vaults and
galleries, so that they might receive more tiers of graves. They made
the galleries somewhat narrower than before, and closer to one
another. At the angles of their intersection, where the friability of the
rock would not admit of full-sized graves being cut, they made
smaller graves for infants, that the space might not be wasted. They
did the same also even in the shelves of rock which had been left as
a necessary support between the several tiers of graves.
Everywhere unnecessary labour was spared; no more soil was
removed than was absolutely necessary for the purpose required.
The graves were made wider at the head and shoulders, and
narrower at the feet; and if two bodies were to be buried in a double
grave (locus bisomus), the soil was excavated only in exact
proportion, the feet of the one being generally laid by the head of the
other.
These expedients, however, could not materially enlarge the
space available for graves, and the fossors were driven to excavate
another flat (so to speak) either above or below the first. And here
they were enabled more easily to provide chambers in which the
faithful could assemble in time of persecution. The first subterranean
chambers had been made small and plain, and rectangular in shape
—mere family vaults apparently; but in the second and third floors
we find them both more numerous, more spacious, and in a greater
variety of forms, furnished also with luminaria, or shafts
communicating with the surface of the ground, whereby light and air
could be supplied to those who were assembled below. Some of
them were decorated with cornices, columns, pilasters, brackets and
chairs, hewn out of the solid rock. To the period of persecution
belong also those galleries which connect parts of the more
important cemeteries with the sandpits in their immediate
neighbourhood—connections which were both studiously concealed,
and, in some instances at least, designedly rendered dangerous to
the use of strangers.