Abstract
The Axiomatic Design (AD) instruments provide a valuable insight for qualitative design evaluation. After having defined the inputs and outputs for the designed system, one can quickly check if it is convenient for the user to address the outputs by the inputs. Thus, AD helps to evaluate the usability of the design or the user interface, although the user interface can be given much wider sense, evaluating the interactions of the design during manufacturing, installation and maintenance. At the same time Axiomatic Design has its restrictions of applicability, which we focus on here. First, AD only shows what design is good, but it provides less guidance on how to make a good/independent design from the existing structure. Second, AD covers the only case where the number of Design parameters is equal to the number of Function Requirements. Finally, AD assumes that the mapping from Design parameters (DPs) to Function Requirements (FRs) is static, whereas very often the influence of DPs on FRs is time-dependent and it also neglects possible valuable resource – the time. In the research these drawbacks have been addressed from Control/System Theory prospective. First of all, we reveal a formal procedure how to construct the independent design for a linear system when the number of DPs is equal to FRs; the idea is based on eigen-decomposition of a matrix. Then, we generalize AD with the time domain, thus making it possible to address dynamic systems and use all the operators of Control Theory. We show that a controller can be added for the system design to make it independent. Finally, we extend the definition of independence to the case where the number of FRs is not equal to the number of DPs.