TAD Section 2.1 — Main System Functions

1     Organization and Formatting

1.1    General (same as for other B-sheets; follow this link for easy reference)

1.2    Sheet-Specific — Making it All Fit

How you lay out the information on the sheet is up to you.  The example provided is simply an example.  Depending on the relative size and aspect ratio of your function structure diagram, rearranging may be needed.  Of course, as usual, the Page Input textbox should be at the top left and the Page Output textbox should remain at the bottom, better yet at the bottom right if at all possible.

2     Content Presentation

  • Commence the sheet by populating the Page Input textbox.  In this case, the page input is information from the use case(s).  These page inputs (and outputs) being included on each page may seem redundant at this point, but they are important to keeping clear to the reader your thought-flow from one page to the next, noting further that connected pages are not always sequential.  The key word there — your — is to realize that your audience reading this cannot read your mind in regard to the logical flow of thinking that resulted in your work-product presented on each sheet.
  • Begin with a single phrase or sentence that defines the overall system function. A pre-titled Overall System Function textbox is provided.
  • Next, in the pre-titled Function Structure Diagram box/frame, provide a function structure diagram drawn in the software of your choice then copied and pasted as a bitmap or other appropriate graphic format.
  • Insert graphical renderings of the functional recomposition table and House of Quality from the DP Manager Excel workbook.  Like for the engineering requirements tables, you should first sort the table in a logical way; that is, use the button provided as doing so will invoke code that will assure no behind-the-scenes formulas (i.e., in hidden rows/columns) or formatting rules get messed up.  Then use the copy table buttons on the Excel worksheet (typically the “Copy Table with Heading” button for use in the TAD).  As previously noted, the code the button triggers places a good resolution picture graphic on the clipboard for then pasting into any other destination.
  • In the pre-titled Notes box, provide relevant clarifying notes about your function structure diagram, main system functions, and house of quality. Include information such as:
    • Describe why your product/process is functionally broken down this way.
    • Describe how the main system functions work together to create a system-level solution to the design problem.
    • Provide reasons and examples for several relationships between the engineering requirements (the “Hows”) with the functions (the “Whats”) and correlations among functions (which indicate areas of extra challenge but also may indicate potential for multi-functional design elements).
    • All clarifications should complement the information in the graphics/tables and not be a simple repetition of the information provided within the graphic/table.
  • Now, for each main system function, graphically “encircle” the elements in the function structure diagram that are grouped into that main system function. In some way indicate the main system function associated with each encirclement (e.g., color coding and/or leaders to main system function names and/or connections/leaders to the main system function table (though that could get messy), and/or your other creative ideas on how to communicate this).  The objective is to make it clear where the main system functions fall within (and groupings of) the detail of the function structure diagram.  It may be easier to do this in the software in which you created the function structure diagram, though there are drawing capabilities in Google Slides that are reasonably good for this purpose.
  • Complete the page by populating the Page Output textbox.  In this case, the page output simply includes where this information is next used and for what and/or how it is used (“where next”).

3     Examples of Great Work

Do a great job and be the first!


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© 2017, William J. Endres Updated September 09, 2022