MICRO-MOTION STUDY: HOW INCREASED WORKSHOP EFFICIENCY IS OBTAINABLE
WITH MOVING PICTURES
In these days of competition it is obvious that the establishment in
which the machinery is most efficient, the workmen most skilful, and
the labour most economically expended has the best chance of success
in its particular line of business. These are the days of scientific
organisation and management, the value of which, developed upon
rational lines, cannot be denied.
But it has remained for the cinematograph to indicate the true lines
along which such developments should be continued. For instance, there
may be two workmen of equal skill and industry, each of whom is given
an identical job. One completes his task in less time than the other,
although the two men are admittedly of equal ability. They may be
checked from stage to stage by the stop-watch, but this will reveal
nothing conclusive, as the advantage from stage to stage will fluctuate
between the two. It is only in the aggregate that the superiority of
the one over the other is seen. The superiority may be so slight as
to be almost negligible, but the fact that it exists is sufficient to
prove that there is something wrong somewhere.
Where is it? How can it be detected? Hitherto scientific management and
stop-watch methods have been found wanting. The riddle can be solved
in one way only, as investigations have shown, and that is by moving
pictures.
This new phase of scientific management has been evolved and perfected
by Mr. Frank B. Gilbreth, of New York, an eminent authority upon
the subject of workshop organisation. He has given it the title of
"Micro-Motion Study." As the name implies it concerns the investigation
of small movements by the ordinary standard cinematograph and the time
measurement of each action.
While this particular line of study may not be entirely new, since
Marey and his contemporaries in the study of movement indicated such a
possible application, yet Mr. Gilbreth is the first to reduce it to a
science. Therefore he is justly entitled to the credit of perfecting
this most important development of scientific management.
Everything depends upon the timing mechanism. This must be of the
simplest type and of unimpeachable accuracy. In a previous chapter
I have described the "chronoscope" which was used by Marey. Mr.
Gilbreth, for the purposes of his work, has evolved a clock working
upon a similar principle. This clock, fitted with one hand, is designed
to make one complete revolution in six seconds. The indications on
its dial are as follows: The larger divisions represent tenths of
a revolution. Each of these is divided into two, thereby showing
twentieths of a revolution, and these latter are further sub-divided
into fifths, so that the dial is divided into one hundred parts. Each
of these divisions represents the thousandth part of a minute, while
the clock can be read easily to half-thousandths of a minute.
This clock, together with one of the ordinary type, is used in each
investigation. Both are prominently displayed in the image so that the
time interval from picture to picture may be determined exactly. The
ordinary clock is necessary, as it shows the total time occupied in an
operation. The special clock, on the other hand, serves for timing the
different stages or motions involved in completing the task.
The principle may be utilised in a variety of ways, as has been proved
at the works of the New England Butt Company of Providence, Rhode
Island. The manager of this concern, Mr. J. G. Aldrich, was one of the
first to recognise the value and possibilities of micro-motion study.
[Illustration: MICRO-CINEMATOGRAPHY: BLOW-FLY EATING HONEY.]
[Illustration: The ingenious Gilbreth clock, graduated to
one-thousandths of a minute.
The rack, showing disposition of component parts for the assembling
test.
MICRO-MOTION STUDY: THE LATEST DEVELOPMENT IN SCIENTIFIC
MANAGEMENT.]
It is an establishment devoted to the manufacture of machinery for
making braiding, such as trimmings for ladies' dresses, and so forth.
The machines are built for the most part from small light castings,
which are machined only slightly, but which must fit together without
the necessity of filing or finicking hand-work. In order to improve
the efficiency of the factory and incidentally to augment its output
and profit, experts were called in from time to time to say where
modifications of process might reduce the manufacturing costs.
Different operations in the assembling of the pieces were timed. The
result was the discovery of more expeditious methods of putting the
pieces together. Such time-study investigations also supplied a basis
for computing the various scales and systems of payment for work done.
Notwithstanding the high pitch of efficiency to which the factory was
brought by these methods, Mr. Aldrich felt convinced that still further
speeding-up might be accomplished without over-driving the men. So he
called in Mr. Gilbreth and his cinematographic method. In order to
obtain the highest results, the most expert workman was taken as the
subject of the experiment.
In one corner of the assembling room the wall and floor were marked off
into four-inch squares. In this space was placed the bench, together
with the sets of component parts. Here there was a slight divergence
from the existing practice in the factory. Instead of taking the
pieces from various boxes, packets of parts were placed in convenient
positions upon a rack. These were placed in the proper sequence, so
that the workman was saved the task of thinking when selecting the
successive pieces. He was able to take them up quickly and correctly in
a mechanical kind of way.
The timing clocks were placed in a prominent position facing the
camera, and when all was ready, the workman was given the word to
start. The whole operation of fitting the pieces of a machine together
were filmed in this manner so as to give a complete cinematographic
record of the assembling of a machine.
Now in micro-motion study the films are not intended for projection.
Instead of being screened, the pictures are studied with the aid of a
magnifying glass, the motion in each picture being closely examined
to detect whether it is essential to the task, whether it might be
eliminated, or shortened. As the wall and floor are marked off into
four-inch squares, the investigator is enabled to ascertain the precise
length of each movement in picking up and fitting the parts. At the
same time, such marking-off enables the expert to see whether the bench
and rack of packets containing the component parts of the machine are
disposed most advantageously in relation to the mechanic, and also
whether the latter stands in the most convenient position before his
work, to fulfil his task in the shortest possible time and with the
minimum of physical effort.
As might be supposed, the individual study of each picture in a film
together with the following and timing of each elementary motion is a
tedious task for the expert. This may be realised when it is pointed
out that the time interval for each picture is only 1/32 part of a
second. But the labour is not wasted. The searching analysis is sure
to reveal where a movement may be accelerated here, or eased there,
why it would be preferable to set the rack in this position, or why
it would be better if the mechanic faced his work in such and such a
way. This is the sole object of micro-motion study. Nothing rivals the
cinematograph for picking a movement relentlessly to pieces.
The most expert workman is taken for the purpose of the investigation
because his skill must be dependent upon his ability to reduce
movements to the minimum. Moreover, he serves as an excellent model
for speeding-up if such is required. By the time his workmanship
has been analysed and perfected by the elimination of all waste or
unnecessary motions, and by his mastery of the best methods, the
photographing in animation of his experience serves as a pattern for
the benefit of all in the factory.
Some remarkable results have been accomplished by this new phase in
scientific management. In the above-mentioned braiding factory the
analysis of the movements incidental to a particular operation enabled
the time occupied upon one task to be reduced from 37-1/2 to 8-1/2
minutes. In other words, the workman was able to perform more than
four times his previous volume of work in an eight-hour day after his
motions had been analysed by the cinematograph. Nor is he driven harder
to achieve this end: he is able to do it because all waste motions have
been eliminated.
The great value of micro-motion study is that it facilitates the
transmission of skill from man to record. It provides a reliable way
of transferring experience from a man who has gained it to one who has
never had it. It acts as a check upon the work. The establishment is
provided with an unassailable record of the time occupied throughout
every department, and consequently holds a complete check upon the
skill and capacity of every man. If there is a decrease in the output,
showing slackness to exist somewhere, it can be traced before material
damage is inflicted. Every workman is kept up to concert pitch, and the
maximum work per man is obtained without resort to driving or rushing.
There is no limit to the applications of micro-motion study. Obviously,
although the best efforts of every man are required, it is essential
that the records should be taken under normal conditions, so as to
provide a fair basis. To introduce special arrangements for the test is
to destroy the value of the investigations, because the other men will
retort that they cannot equal the performance unless they have the same
facilities.
The workmen are never permitted to see the moving-picture record of
their work. Neither are they shown contrasting views of how and how not
to do a thing. The pictures are merely for the use of the investigator.
When it is necessary to communicate the results of an experiment to the
workman, he is given no opportunity for argument. He is merely told
how to do this or that, according to the experience gathered from an
intimate study of the photographic record.
This application of the cinematograph has been developed also for
the benefit of apprentices. A youth who is trained on the correct
lines from the very commencement of his duties has the best chance of
becoming an expert workman, and for him the use of micro-motion study
is invaluable. He can be taken through every separate motion step by
step, the film used for this purpose being that of the most perfectly
skilled man. Experience has shown, moreover, that a youth can learn his
craft more quickly and intelligently by following it upon the screen
than by being brought face to face with the actual work at the bench.
He appears to concentrate his attention better upon the moving-picture
lesson than upon the practical demonstration, although in both cases
the appeal is made to the eye.
There is yet another valuable aspect of this work. Enterprising and
ingenious men are constantly devising improved processes in factory
equipment. At times their revolutionary ideas are put into practice
before they are thoroughly understood, and the result is far from
satisfactory. The improvement proves to be more imaginary than real.
But if recourse is first had to the cinematograph, the process can be
submitted to a searching practical trial before it is installed. A film
can be taken and each separate image can be examined minutely with the
aid of the magnifying glass, until a pretty complete idea is gained as
to the true value of the invention. The pictorial time record can be
compared with the best results secured under the existing practice, and
the manufacturer can ascertain what economies the new plan will effect
before a penny is expended, or the working of his factory disorganised
by the alteration.
[Illustration: Mr. Frank B. Gilbreth cinematographing a man's work
against time, showing the Gilbreth clock.
Bench and parts arranged after test so as to secure assembling of
machine with fewest and shortest motions.
THE GILBRETH METHOD FOR IMPROVING FACTORY EFFICIENCY.]
[Illustration:
1 2
MICRO-MOTION STUDY: FILMS SHOWING HOW A MAN'S WORK IS ANALYSED BY
MOVING PICTURES.
These pictures are not thrown on the screen, but are examined by a
magnifying glass.
(1) Film of workman assembling machine, showing Gilbreth clock and
ordinary timepiece alongside.
(2) Film of rack and bench, floor marked off into 4-inch squares, and
Gilbreth clock.]
Micro-motion study by the aid of the cinematograph is still in its
infancy. But it appears to have a wide field of utility. The pictures
can be taken at any desired speed, according to the character of the
work photographed, but as a rule sixteen pictures per second will
suffice. It must be remembered that in this case the record is not
obtained for the purpose of studying movement from the scientific or
physiological point of view, as with Marey's investigations, but purely
for the purpose of discovering whether certain motions are necessary to
certain tasks. Obviously the expert engaged in this work must possess
an intimate knowledge of movement so as to be able to follow the
motions closely and accurately through their natural cycles, and must
also be familiar with the work of the factory so as to tell whether
a man is working to the best advantage. This faculty alone demands a
long apprenticeship, for experience is the only guide. Mr. Frank B.
Gilbreth, who has brought micro-motion study prominently before the
public, has devoted years to the subject. He has become an unique
authority upon it. Now that its advantages are appreciated, one may
expect it to fill an even wider space in industrial life, and to be
applied in many directions that are as yet undreamed of.