Introduction to Industrial Engineering and Management

Industrial engineering (IE) is the branch of engineering concerned with the design, improvement and installation of integrated systems of men, materials, equipment and energy. Its growth followed the growth of factories.

Early period

• Industrial Revolution (18th century): Machines and the factory system replaced craft production. Adam Smith described division of labour (1776) and Eli Whitney introduced interchangeable parts.
• Charles Babbage (1832): studied the economics of machinery and the division of work.

Scientific management

• F. W. Taylor (1856-1915): the "father of scientific management". He introduced time study, standard times, functional foremanship and the differential piece-rate system, and gave four principles: scientific method for each task, scientific selection and training of workers, cooperation between management and workers, and equal division of work and responsibility.
• Frank and Lillian Gilbreth: motion study, therbligs (basic motions) and the process chart.
• Henry L. Gantt: the Gantt chart for scheduling and a task-and-bonus wage system.
• Harrington Emerson: twelve principles of efficiency.

Administrative and mass production period

• Henri Fayol: five functions of management (planning, organising, commanding, coordinating, controlling) and fourteen principles of management.
• Henry Ford (1913): moving assembly line and standardisation.

Later developments

• Hawthorne studies (Elton Mayo, 1924-32): showed the importance of human and social factors.
• Shewhart, Deming, Juran: statistical quality control and later quality management.
• World War II: operations research, linear programming and simulation.
• After 1950: computers, MRP, JIT/Toyota production system, TQM, and today automation and information systems.

A system is a set of interrelated components working together towards a common objective within a boundary, with an environment outside the boundary. The system concept helps an industrial engineer see the whole factory as connected parts rather than as separate departments, so that improving one part does not harm the rest (avoiding sub-optimisation).

Characteristics of a system

• It has a clear objective and a boundary.
• Its parts (sub-systems) are interdependent.
• It takes inputs and converts them into outputs.
• It interacts with the environment (market, government, suppliers).
• It uses feedback for control.

Production system model

 INPUTS            TRANSFORMATION           OUTPUTS
 Men        +---------------------+    Goods
 Materials  |  Machining,         |    Services
 Machines ->|  assembly, testing, |->  Waste/scrap
 Money      |  packing            |
 Information+---------------------+
      ^                                    |
      |       FEEDBACK / CONTROL           |
      +-----(quality, cost, delivery)------+

• Inputs: the 5 Ms - men, materials, machines, money, methods (plus information and energy).
• Transformation: the conversion process that adds value.
• Outputs: products, services, by-products and waste.
• Feedback: measured output (quality, cost, delivery time) is compared with the standard. If a difference exists, corrective action is taken on the inputs or the process. For example, rising rejection rate in a machine shop leads to tool change or operator training.

Example: In a furniture workshop, wood, labour and machines (inputs) are cut, assembled and polished (process) to give furniture (output); customer complaints act as feedback.