Date of Award

Summer 2002

Document Type


Degree Name

Doctor of Philosophy (PhD)


Mechanical & Aerospace Engineering


Mechanical Engineering

Committee Director

Han Bao

Committee Member

Sebastian Bawab

Committee Member

Resit Unal

Committee Member

Keith M. Williamson


This research creates a design methodology by synthesizing three different design tools, the Theory of Inventive Problem Solving (TRIZ), the Theory of Constraints (TOC) and Logic. The basic approach of this design method is to: (1) Reduce a design problem to a logic diagram, (2) Code the inputs and outputs to determine desirability and degree of control, (3) Identify the best inputs to manipulate in order to obtain the desired outputs and (4) Exploit innovative algorithms developed in TRIZ to find the best ways to manipulate the chosen inputs.

This research integrates and expands the methods of TRIZ and TOC. It expands TOC by: (1) Expanding the levels of control from three to five, (2) Adding additional logical operators to the toolset and (3) Allowing for quantitative and qualitative variables to be treated as analog circuitry.

It expands TRIZ by: (1) Allowing for three levels of desirability (desirable, neutral and undesirable) instead of only two (useful and harmful), (2) Focusing the design area to keep the number of design solutions from increasing exponentially and (3) Allowing for logical operators to be used with the TRIZ toolset.

This dissertation integrates the strength of TRIZ (powerful innovative idea generation) with the strength of TOC (focused design) along with the strength of logical operators, In addition to providing a method, this research also provides a questionnaire to guide the designer through the methodology. This dissertation bangs the power of focused innovation to early design stages.


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