ABSTRACT
The major elements of this theory are: design personnel (the engineering designer and HF specialist), the system to be designed, and the world (e.g., a factory, an external environment) that the system is designed to monitor and/or control. Supporting elements include: the goals set by the customer’s wishes, the nature of the design problem that is created by the disparity between those goals and what is presently available to a consumer, the functions to be performed by design personnel (which are primarily cognitive) to solve the design problem, the data available to assist in solving the problem, the tests (both physical and mental) made by the design team in collecting information and to verify hypotheses, the feedback from those tests, and the perceptions of the design personnel that, although mental, are quite real because they have real effects on design processes.
