Work System Design

Dr. Subhajit Sidhanta

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Department of Industrial Engineering & Management

Indian Institute of Technology (IIT) Kharagpur

West Bengal, India

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“Simplicity boils down to two steps: Identify the essential. Eliminate the rest.” �― Leo Babauta

Dr. Jitesh Thakkar, IIT Kharagpur

1. WORK SYSTEM DESIGN: TIME STUDY, MOTION STUDY, ASSEMBLY LINES
2. ERGONOMICS: HUMAN FACTOR
3. COGNITIVE DESIGN
4. CYBER PHYSICAL HUMAN SYSTEMS

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PRODUCTIVITY IMPORTANCE

Wherever people, materials, and facilities interact to obtain some objective, productivity can be improved through the intelligent application of methods, standards, and work design.

Dr. S Sidhantar, IIT Kharagpur

Methods engineering includes designing, creating, and selecting the best manufacturing methods, processes, tools, equipment, and skills to manufacture a product based on the specifications that have been developed by the product engineering section.

SCOPE

Dr. S Sidhantar, IIT Kharagpur

METHODS ENGINEERING

The terms operation analysis, work design, work simplification, and methods engineering and corporate reengineering are frequently used synonymously. In most cases, the person is referring to a technique for increasing the production per unit of time or decreasing the cost per unit output—in other words, productivity improvement.

First, the methods engineer is responsible for designing and developing the various work centers where the product will be produced. Second, that engineer must continually restudy the work centers to find a better way to produce the product and/or improve its quality.

As part of developing or maintaining the new method, the principles of work design must be used to fit the task and workstation ergonomically to the human operator.

The principal objectives of methods, standards, and work design are

1. to increase productivity and product reliability safely and
2. to lower unit cost, thus allowing more quality goods and services to be produced for more people.

1. Minimize the time required to perform tasks.
2. Continually improve the quality and reliability of products and services.

3. Conserve resources and minimize cost by specifying the most appropriate direct and indirect materials for the production of goods and services.

4. Consider the cost and availability of power.

5. Maximize the safety, health, and well-being of all employees.

6. Produce with an increasing concern for protecting the environment.

7. Follow a humane program of management that results in job interest and satisfaction for each employee.

OBJECTIVES

Historical Figures Related to Work

• Eli Whitney (1765-1825)
• Interchangeable parts manufacture
• Henry Ford (1863-1947)
• Moving assembly line
• Frederick W. Taylor (1856-1915)
• Scientific management
• Time study
• Frank (1868-1924) & Lillian Gilbreth (1878-1972)
• Motion study

Dr. Jitesh Thakkar, IIT Kharagpur

Dr. Jitesh Thakkar, IIT Kharagpur

Work

• Is our primary means of livelihood
• Serves an important economic function in the global world of commerce
• Creates opportunities for social interactions and friendships
• Provides the products and services that sustain and improve our standard of living

The Nature of Work

Work is an activity in which one exerts physical 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 compensated

Work (Physics Definition and Pyramidal Structure)

The displacement (distance) that an object moves in a certain direction multiplied by the force acting on the object in the same direction.

• Units of measurement:
• Newton-meters (N-m) in the International System of Units (metric system)
• Foot-pounds (ft-lb) in U.S. customary units
• Work consists of tasks
• Tasks consist of work elements
• Work elements consist of basic motion elements

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An amount of work that is assigned to a worker or for which a worker is responsible

• Repetitive task – as in mass production
• Time required = 30 seconds to several minutes
• Non-repetitive task – performed periodically, infrequently, or only once
• Time required usually much longer than for repetitive task

Task

Dr. Jitesh Thakkar, IIT Kharagpur

Each task consists of several work elements, and each work element consists of basic motion elements. Basic motion elements arere actuations of the limbs and other body parts while engaged in performing the task. These basic motion elements include reaching for an object, grasping an object, or moving an object. Other basic motions include walking and eye movement (e.g., eye focusing, reading). Multiple basic motion elements are generally required to perform a work element, which is defined as a se of work activities that are logically grouped together because they have a unified function within the task.

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 bolts
• Required time = six seconds or longer

Basic Motion Elements

Actuations of the limbs and other body parts

• Examples:
• Reaching for an object
• Grasping the object
• Moving the object
• Walking
• Eye movement
• A work element consists of multiple basic motion elements

Dr. Jitesh Thakkar, IIT Kharagpur

Importance of Time

• In many human endeavors, “time is of the essence”
• In sports
• In daily living
• In business and industry
• In work

• New product introduction
• Product cost
• Delivery time
• Overnight delivery
• Competitive bidding
• Production scheduling

Time in Business and Industry

Importance of Time in Work and Work System Defined

• Time is the most frequently used measure of work
• How many minutes or hours are required to perform a given task?
• Most workers are paid by the time they work
• Hourly wage rate
• Salary
• Workers must arrive at work on time
• Labor and staffing requirements computed in units of time

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
• Examples:
• Worker operating a machine tool in a factory
• Robotic welding line in an automobile plant
• Parcel service agent driving a delivery truck to make customer deliveries
• Designer working at a CAD workstation

A Work System as a Physical Entity

As a field of professional practice, work systems include:

• Work methods - analysis and design of tasks and jobs involving human work activity
• Work measurement – analysis of a task to determine the time that should be allowed to perform the task
• Work management – organizational and administrative functions that must be accomplished to achieve high productivity and effective supervision of workers

Jobs and Occupations

• Bureau of Labor Statistics of the U.S. Department of Labor identifies 821 occupations in its Standard Occupational Classification (SOC)
• The SOC covers virtually every type of work performed for pay or profit in the United States
• Occupations are organized into 23 major groups
• Groups are established on the basis of type of work and/or the industry in which it is performed

• Four broad categories that reflect the 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
4. Knowledge workers - create new knowledge, solve problems, manage

Comparisons: Industries and Workers

1. Production workers
• Manufacturing, construction, agriculture
2. Logistics workers
• Transportation, distribution, material handling
3. Service workers
• Banking, retail, government, health care
4. Knowledge workers
• Management, engineering, legal, consulting, education

Refers to the need to make responsible decisions and exercise judgment in carrying out duties of the position

• Jobs that are highly standardized and routine require minimum worker discretion
• 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
• Typical for service and knowledge workers

Productivity

The level of output of a given process relative to the level of input

• Process can refer to
• Individual production or service operations
• A national economy
• Productivity is an important metric in work systems because
• Improving productivity is the means by which worker compensation can be increased without increasing the costs of products and services they produce

• The most common productivity measure is labor productivity, defined by the following ratio:

LPR =

where LPR = labor productivity ratio, WU = work units of output, LH = labor hours of input

Labor Productivity

Labor Factor in Productivity

• Labor itself does not contribute much to improving productivity
• More important factors:
• Capital - substitution of machines for human labor
• Technology - fundamental change in the way some activity or function is accomplished

Horse-drawn carts

Steam locomotive

Telephone operator

Dial phone

Manually operated milling machine

DC-3 passenger airplane (1930s)

Railroad trains

Diesel locomotive

Dial phone

Touch-tone phone

Numerically controlled (NC) milling machine

Boeing 747 passenger airplane (1980s)

Examples of Technology Changes

Capital versus Technology

• Distinctions between capital improvements and technology improvements are often subtle
• New technologies almost always require capital investments
• Important to recognize important gains in productivity are more likely to be made
• By the introduction of capital and technology in a work process
• Than by attempting to get more work in less time out of the workers

Dr. Jitesh Thakkar, IIT Kharagpur

Measuring Productivity

• Not as easy as it seems because of the following problems:
• Nonhomogeneous output units
• Multiple input factors
• Labor, capital, technology, materials, energy
• Price and cost changes due to economic forces
• Product mix changes
• Relative proportions of products that a company sells change over time

Measure that compares input/output ratio from one year to the next

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LPI =

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where LPI = labor productivity index, LPR_t = labor productivity ratio for period t, and LPR_b = labor productivity ratio for base period

Example: Productivity Measurement

• During the base year in a small steel mill, 326,000 tons of steel were produced using 203,000 labor hours. In the next year, the output was 341,000 tons using 246,000 labor hours.

Determine: (a) the labor productivity ratio for the base year, (b) the labor productivity ratio for the second year, and (c) the productivity index for the second year.

(a) In the base year, LPR = 326,000 / 203,000

= 1.606 tons per labor hour

(b) In the second year, LPR = 341,000 / 246,000

= 1.386 tons per labor hour

(c) Productivity index for the second year

LPI = 1.386 / 1.606 = 0.863

• Comment: No matter how it’s measured, productivity went down in the second year.

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Productive Work Content

A given task performed by a worker can be considered to consist of

• Basic productive work content
• Theoretical minimum amount of work required to accomplish the task
• Excess nonproductive activities
• Extra physical and mental actions of worker
• Do not add value to the task
• Do not facilitate the productive work content
• Take time

Can be classified into three categories:

• Excess activities due to poor design of product or service
• Excess activities caused by inefficient methods, poor workplace layout, and interruptions
• Excessive activities cause by the human factor

Allocation of Total Task Time

• Products with more parts than necessary, causing excess assembly time
• Product proliferation
• Frequent design changes
• Waste of materials
• Quality standards too stringent

Inefficient Methods, Layout, Etc.

• Inefficient layout that increases material handling activities
• Inefficient workplace layout that increases hand, arm, and body motions
• Methods that include unnecessary work elements that waste time
• Long setup times in batch production
• Frequent equipment breakdowns
• Workers waiting for work

• Absenteeism
• Tardiness
• Workers spending too much time socializing
• Workers deliberately working slowly
• Inadequate training of workers
• Industrial accidents caused by human error
• Hazardous materials that cause occupational illnesses

OPERATIONS STRATEGY

The importance of work design is underscored by an organization’s dependence on human efforts (i.e., work) to accomplish its goals.

JOB DESIGN

JOB DESIGN

• The act of specifying the contents of and methods of jobs.
• What? Who? How? Where?
• Ergonomics – Incorporation of human factors in the design of the workplace

(design of equipment, work methods and overall design of the work environment)

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Factors that Affect Job Design

• Workers and managers consultation
• Managerial support
• Written record establishment

Elements

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• Efficiency school – systematic and logical
• Behavioral school- satisfaction of wants and needs

The main rationale for specialization is the ability to concentrate one’s efforts and thereby become proficient at that type of work.

• Work that concentrates on some aspect of product or service

BEHAVIORAL APPROACHES�TO JOB DESIGN

• Job Enlargement – Giving a worker a larger position of the total task
• Job Rotation – Workers periodically exchange jobs
• Job Enrichment – Increasing responsibility for planning and coordination tasks, by vertical loading.

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• Increase the motivational power of jobs by increasing worker satisfaction through improvement in the quality of work life

MOTIVATION

• Key factor in many aspects of work life
• Influence quality and productivity
• Contributes to the work environment
• Trust – influences motivation, productivity and employee-management relations

Why do people work?

• Compensation
• Socialization
• Self-actualization
• Status
• Physiological aspects of work
• Sense of purpose and accomplishment

TEAMS

• Short-term team
• Long-term team
• Self-directed teams (self-managed teams)- designed to achieve higher level of teamwork and employee involvement. Although such teams are not given absolute authority to make all decisions, they are typically empowered to make changes in the work processes under their control

Successful Team Building Requirements

1. Clearly stated and commonly held vision and goals
2. Talent and skills required to meet goals
3. Clear understanding of team members’ roles and functions
4. Efficient and shared understanding of procedures and norms
5. Effective and skilled interpersonal relations
6. A system of reinforcement and celebration
7. Clear understanding of the team’s relationship to the greater organization

Expenditure of resources for any goal other than the creation of value for the end customer is wasteful, and thus a target for elimination.

Dr. Jitesh Thakkar, IIT Kharagpur