Chapters 1 and 2

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Chapters 1 and 2

• Problem Solving Tools for Methods Engineering

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Our Text Book Website

• http//highered.mcgraw-hill.com/sites/0072468246/

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Outline for today

• A short history of Human Factors and Ergonomics,
• Methods Engineering/Work Design
• Example of Methods Engineering
• Discussion of in-class exercise,
• Approaches for both physical and thinking
  tasks,

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A Short History of Human Factors and Ergonomics
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Methods Engineering

• Technique for
• Increasing production per unit of time.
• Example increasing the number of customers
  that can be handled per cashier by installing bar
  code readers.
• Decreasing cost per unit output.
• Example decreasing total cost of each cell
  phone by reducing the number of parts and thus
  the labor hours required for assembly.
• It is critical to look at impact on whole system.

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Methods Engineering Focuses Primarily on
improving productivity though (re)design of
Motivation Incentives/rewards
Organizational structure
Work Process
Work operations
Tools (Products)
Work environment
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Methods Engineering

• Often used synonymously with
• Corporate re-engineering
• Work design
• Operation analysis
• The difference between these terms in the level
  of detail.

Big picture level
Detail level
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Methods Engineering

• Select project
• I.D. product or service experiencing
  difficulties.
• Get and present data
• Study situation, take measurements to
  determine where difficulties really lie,
• Analyze the data
• Figure out which of many problems are most
  critical
• Develop ideal method(s)
• Identify alternative approaches which may
  address most critical problems.

• Present and install method
• at the work site
• Develop a job analysis
• To insure operators are adequately selected,
  trained, rewarded, etc.
• Establish time standards
• Establish fair and equitable standards for
  work performance.
• Follow up the method
• Take measurements to determine if changes
  really did improve situation as predicted.

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Example Mission Planning and control for the
Mars Exploration Rover

• Researchers introduced automated planning tool,
  MAPGEN
• Tool had to fit with users existing way of
  thinking about plans,
• Introduction of new tools caused the planning
  process to change,
• Product and processes were evolved together, over
  time.

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Many methods can be used in many stages of the
design process
A typical spiral design process
Prototype Testing
Requirements Gathering
Final Performance Evaluation or Comparison
Design Specification
Design Review
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Problem Solving Tools for Methods Engineering
help to identify what the most important problem
is

• Observational tools
• Site walk-thrus
• Observation and interviews of workers and
  managers
• Ethnographic studies

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Problem Solving Tools for Methods Engineering
(Ch. 2.1)

• Exploratory tools
• Pareto Analysis (Vilfredo Pareto)
• Fish Diagrams (from Japan, 60s)
• Gantt and PERT charts (40s wartime).

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Pareto Analysis

• Items of interest are identified (e.g. types of
  product flaws that result in scrapped parts, time
  spent on each activity required to manufacture a
  product or perform a service.
• Items are measured on a common scale (such as
  frequency total cost, total time, etc.)
• Items are ordered in descending order

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Example of a Pareto Chart
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Fish Diagrams

• Cause and effect diagrams
• Effect is a problem fish head
• Causes fish bones
• Typical causes
• Environment
• Methods
• Materials
• Administrative
• Machine
• Human

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Gantt Charts

• Activities shown as bars with
• Anticipated start times
• Anticipated completion times
• Actual start and completion times
• Use a vertical line to show current time
• May use color codes to show various things
• Completed activities (grey)
• On going activities, on schedule (green)
• Overdue activities (red)
• Almost over due activities (yellow)

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PERT ChartsProgram Review and Evaluation
Technique

• Project networks
• Like Gannt charts, PERT charts show activities,
  start and end times
• Also show variation in activity durations
  optimistic, average, pessimistic,
• Show dependencies between activities,
• Can identify a critical path (longest path) that
  constrains minimum completion time of whole
  project,
• Analyze how crashing activities can shorten
  duration of whole project.

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Problem Solving Tools (cont.)

• Recording and Analysis tools
• Operation Process Chart
• Flow process chart
• Flow diagram
• Worker and Machine Process Charts
• Gang Process charts
• Synchronous servicing

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Operation Process Charts

• Chronological sequence of operations
• Show operations as a flow chart though the
  worksite.
• Show the types of operations
• Operation
• Transport
• Inspection
• Delay
• Storage
• Decision

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Operation Process Chart Manufacture of a
telephone stand
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Flow Process Chart

• More detail than Operation Process Chart
• Not usually used for entire assemblies,
• Used for just one component (or operator)
• Add in information on
• Operation duration (time to complete)
• Distance traveled (for transport operations)
• Good for showing savings of a new method.

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Flow Diagram

• Show layout of work area
• Show the flow of work through that area
• Show congestion areas, crossing worker paths,
  total travel.
• Identify how layout can be redesigned to reduce
  travel, motion, collisions, etc.
• Store materials near where they are used.
• Increase efficiency and safety.

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Worker and Machine Process Chart

• Show one worker, many processes
• Identify idle time for each,
• Reorganize operations to reduce idle time.
• Identify how many machines worker can manage

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Gang Process Charts

• Show one machine, many workers,
• Identify idle time for each,
• Re-arrange tasks between workers to reduce idle
  time.

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Tools for Time and Motion Studies

• Tools can be simple and low cost
• Stop watch,
• Pen and paper,
• Maybe a video camera. The task determines if it
  is necessary.
• The technique is low-tech, but can still result
  in major cost savings!

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Common themes in Human Factors approaches

• Observation of human activities in performance of
  tasks,
• Re-engineer many aspects of the task (tools,
  process, etc.) to improve effectiveness
• The tools and techniques are often simple but
  powerful!

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In-Class Exercise

• Each group will be given a set of objects to
  assemble into a box.
• The items will be varied in
• shape
• size,
• flexibility,

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In-Class Exercise

• Figure out how to fit all the objects in the box
• Decide what actions constitute therbligs or
  elements
• Develop and record a procedure (in terms of
  therbligs)
• Figure out how to do it fast
• Time your procedure (minutes, seconds)
• Did your therblig descriptions change?
• Did your procedure descriptions change?
• Did other things change?

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Rules of Exercise

• Take all objects out and set them separately on
  desk.
• Fit all objects in the box so that you can close
  the lid all the way.
• No squashing or damaging objects.
• You may wish to assign different roles to the
  people on your team packer, time keeper, process
  recorder, observer, etc.
• You will get several minutes to practice, then we
  will have a competition.

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Exercise (continued)

• Each group please report
• Your best time to complete the task
• Your therbligs
• Your procedure (sequence of therbligs)
• What you did to improve your time? (did you
  develop new therbligs? New sequence? Other?)