ABSTRACT
While in a theoretical sense there is always a transfer function between various steps of product development in my experience, those transfer functions have been too elusive and high level to be expressed in any practical mathematical forms. However, at the subsystem and assembly levels, with a little effort, various transfer functions can be developed. From a practical point of view, the design engineer needs this information to identify the variables impacting the design. To do this, a mathematical form of the transfer function is needed. Often, governing equations derived on the basis of physics and engineering constitute these functions.
