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Motion and Time Study
WORK SYSTEMS
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Historical Figures Related to Work
Industrial Revolution (1770’s)J W tt (1736 1819)o James Watt (1736 –1819)
steam engine
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Historical Figures Related to Work
Henry Maudslay (1771 – 1831)o Screw‐cutting lathe (1800)o Standardization of screw thread sizeso Interchangeability
o The first bench micrometer capable ofmeasuring to one ten‐thousandth of aninch (0.0001 in ≈ 3 µm).
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Eli Whitney (1765‐1825)
Cotton gin (1793)
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Eli Whitney (1765‐1825)
Muskets(Interchangeable parts manufacture)opromotion and popularizingoproduces 10,000 muskets for the USgovernment
o Standard partso Special tools, fixtures etc.U i d t l toUnique products replaces custom‐fabricate products
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Henry Ford (1863‐1947)oMass productionoMass productionoAssembly lineoModel T for less than $500 in 1916Movie 1
Movie 2
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Frederick W. Taylor (1856‐1915)
Father of Scientific Management (late 1800s)& IE& IEFirst to use a stop watch (father of time study)
1. Motion study– Finding the best method to perform a given task
2. Time studyy– To establish work standards for a job
3. Extensive use of standards in industry4. Piece rate systems & similar labor incentive plans5. Data collection, record keeping, and cost accounting
factory operations. 11
Taylor’s Shoveling Experiment
before after studybefore after study
No people 400‐600 140
lb/shovel 3.5‐38 21.5
Bonus no yes
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Work unit teams individual
Cost/ton 7‐8c 3‐4cA saving of $78,000/year
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Pig iron handling
Yard workers who loaded pig irons f t d t f i htfrom storage yard to freight cars were not using the best method.
– Work too hard ( had to rest for too long)– Daily wage was $1.15 (1898)– Averaged 1 5 tons per day
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Averaged 1.5 tons per day– Schmidt ($1.85)
– Improvements (pick up, carry, drop off, more frequent but shorter breaks)
– 47 tons per day
Frank (1868‐1924) & Lillian Gilbreth (1878‐1972)
Father (mother) of motion studyAll works are composed of basic motionelements (therbligs)elements (therbligs)There is one best method to perform a certaintask.Cheaper by the Dozen
o Motion study (finding the best method to perform a task)o Time study to establish work standards for a jobo Use of standards in industryyo Labor incentives (bonus payments for higher outputs)o Use of data collection, record keeping, cost accounting
o The objective is to improve the (labor) productivity
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Bricklaying
Bricklayer assigned to teach him laid bricks in three different ways:different ways:o Normal way, when working fast, when instructingOther bricklayers used other (different )methods
One best way to accomplish bricklayingAll bricklayers should use ityReduced number of steps required to lay one brick by 70%Adjustable bricklayer’s scaffold
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Work
Is our primary means of livelihood
Serves an important economic function in the global world of commerce
Creates opportunities for social interactions and friendshipsand friendships
Provides the products and services that sustain and improve
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The Nature of Work
Work is an activity in which one exerts
physical and mental effort to accomplish aphysical and mental effort to accomplish a
given task or perform a duty
Task or duty has some useful objective
Worker applies skills and knowledge for
successful completion
The activity has commercial value
The worker is compensated18
Work (Physics Definition)
The displacement (distance) that an object moves in a certain direction multiplied by the forcein a certain direction multiplied by the forceacting on the object in the same direction.
W=Fμd (Newton‐meter)
Units of measurement: o Newton‐meters (N‐m) in the International System of Units (metric system)(metric system)
o Foot‐pounds (ft‐lb) in U.S. customary unitsWork is more than muscular applications.
Combination of physical and cognitive work.
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The Pyramidal Structure of Work
Work consists of taskso Tasks consist of work elements
Work elements consist of basic motion elements
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Task
An amount of work that is assigned to a worker
or for which a worker is responsibleor for which a worker is responsible
Repetitive task – as in mass production
o Time required = 30 seconds to several minutes
Non‐repetitive task – performed periodically, p p p y,
infrequently, or only once
o Time required usually much longer than for repetitive task
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Work Element
A series of work activities that are logically grouped
together because they have a unified function in the task
Example: assembling a component to a base part using
several nuts and boltso Reaching for a parto Grasping ito Attaching it to a base parto Attaching it to a base part
Required time = six seconds or longer
A work element consists of multiple basic motion elements
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Basic Motion Elements
Actuations of the limbs and other body parts
Examples:o Reaching for an object
o Grasping the object
o Moving the object
o Walking
o Eye movement
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Pyramidal Structure of Work
Extended to a worker’s career
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Importance of Time
In many human endeavors, “time is of the
essence”
o In sports
o In daily living
I b i d i d to In business and industry
o In work
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Time in Business and Industry
New product introductiono Shortest time −> most profitso Shortest time > most profits Product cost o Labor hours represent a significant portion of total manufacturing cost
Delivery time o Supplier with shortest delivery time is selectedO i ht d lio Overnight delivery
o Competitive bidding:Production scheduling
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Importance of Time in Work
Time is the most frequently used measure of workworko How many minutes or hours are required to perform a given task?
Most workers are paid by the time they worko Hourly wage rate o Salary
Workers must arrive at work on timeStudents must arrive at class on timeLabor and staffing requirements computed in units of time
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Work System Defined
As a physical entity
A field of professional practice
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A Work System as a Physical Entity
As a physical entity, a work system is a system consisting of
humans, information, and equipment designed to perform
useful work
Contributes to the production of a product or delivery of a
service
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A Work System as a Physical Entity
Examples:
o Worker operating a machine tool in a factory
o Robotic welding line in an automobile plant
o Parcel service agent driving a delivery truck to
make customer deliveries
o Designer working at a CAD workstation
o A receptionist answering incoming phone calls30
Work System Defined as a field of professional practice
As a field of professional practice, work systems include:p p , y
A. Work methods
B. Work measurement
C. Work management
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Work methods ‐ analysis and design of tasks and
Work System Defined as a field of professional practice
jobs involving human work activity
o Motion study (physical motion, tools, & work place
layout)
o Operations analysis & methods engineering (less
restrictive and include the analysis and design of
complex processes: material and information)
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Work measurement – analysis of a task to
determine the time that should be allowed to
Work System Defined as a field of professional practice
determine the time that should be allowed to
perform the task (standard time)
Product costs
Worker performance
Worker requirementsq
Standard time
– How long it takes to accomplish a given work
o (Time=Money)
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Work management – organizational and
Work System Defined as a field of professional practice
administrative functions that must be
accomplished to achieve high productivity and
effective supervision of workerso Organizing workerso g g
o Motivating workers
o Evaluating jobs
o Evaluating performances
o Compensating workers (labor wages)35
Jobs and Occupations
Four broad categories that reflect the work content and job function:work content and job function: 1. Production workers ‐make products
2. Logistics workers ‐move materials, products, or people
3. Service – provide a service, apply existing information and knowledge, communicate g
4. Knowledge workers ‐ create new knowledge, solve problems, manage
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Comparisons: Industries and Workers
1. Production workers ko Making products
o Manufacturing, construction, agriculture
2. Logistics workers o Moving materials, products, people
o Transportation, distribution, material handling
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Comparisons: Industries and Workers
3. Service workers l fo Providing service, applying existing information
knowledge, communicate
o Banking, retail, government, health care
4. Knowledge workers o Creating knowledge, solving problems, managing
o Management, engineering, legal, consulting, education
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Comparisons: Worker Discretion
Refers to the need to make responsible decisions and exercise
j d i i d i f h i ijudgment in carrying out duties of the position
Jobs that are highly standardized and routine require
minimum worker discretion
o Typical for production and logistics workers
Jobs in which workers must adapt their behavior in
response to variations in the work situation require high
discretion
o Typical for service and knowledge workers 42