FUNCTIONAL DECOMPOSITION

The project goal is to design and virtually test a parade float by May 2020. This project goal can be approached in a multitude of ways. A physical understanding behind the functions of a parade float are crucial to the successful development of a design plan. Functional decomposition is an unbiased method of relating main functions of an item to the more basic functions of the same item. For this project, functional decomposition will allow for further insight into basic necessities for our design, to aid in the process of concept generation. Functional decomposition can be accomplished through flowchart methods and/or hierarchical chart methods, starting from more general functions at the beginning, and synthesizing these into the more specific functions near the end. For this project, a hierarchical chart method was used to allow for visual representation purposes. The hierarchical chart functions were determined by a process including analyzing customer needs and researching common functions of parade floats.

Functional Decomposition Hierarchical Chart

The functional decomposition hierarchical chart was then analyzed to construct a cross reference matrix that displays relationships between main functions and basic functions. Functions can relate to one another in a variety of ways. A common functional relationship is that more than one main function can be synthesized into similar basic functions. An example of this would be that the main functions, “Navigate Routes” and “Display Visual Representations” can both be synthesized into more basic functions, one of them including “Supply Power”. In this example, “Supply Power” is the common function that relates the two main functions. Functional relationships like this are displayed in a cross-reference matrix.

A cross-reference matrix is a helpful functional decomposition tool, constructed using the hierarchical chart to identify the most important basic functions of a potential design. Relationships between main and basic functions are determined by finding how often a basic function appears and the main function it’s supporting. The relationships are documented by the indicator ‘X’ on the cross-reference matrix.

Functional Decomposition Cross-Reference Matrix

	Navigate Routes	Display Visual Elements	Protect Infrastructure
Regulate velocity	X
Turn	X
Accelerate	X
Decelerate	X
Regulate Stability	X
Secure Elements	X
Support Weight Distribution	X		X
Display Engineering Disciplines			X
Present College Branding		X
Highlight College Success Statistics		X
Capture Attention		X
Move objects of Visual Interest		X
Generate Motion		X
Supply Power	X	X
Resist Failure			X
Withstand Outdoor Weather Conditions			X
Maintain Storable Size			X

From the cross reference matrix, no basic function was directly related to all three main functions. The important outcome of this matrix was that two subfunctions, “Supply Power” and “Support Weight Distribution,” had the highest frequency in the cross-reference matrix, appearing two times. All the functions are utilized when generating concepts, however, these two sub functions specifically draw attention to the main function that they share, “Navigate Parade Routes.” This analysis narrows the project objective and allows for a focus on “Navigate Parade Routes” first, followed by “Protecting Infrastructure” and then “Display Visual Elements.”