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Product-Centred Modelling

My overall framework for product modelling work. It used to be called Artifact-Centred Modelling.

An overall framework, called Product Centred Modelling (PCM) is being developed. This framework divides the overall problem into a matrix arrangement using two axes of abstraction: by organizational structure on the one hand, and by levels of reasoning abstraction on the other.

Overview of PCM

PCM is based on separating design activities along two axes of abstraction:

Functional Abstractions Structural Abstractions
Designs & mfg systems Products
Design processes Product & Process Models
Eng Mgmt processes Modeling languages
Language theories

The most recent published definition of PCM is given in [Sal95].

Open Issues

  • The PCM matrix is suprisingly similar to some IT infrastructure frameworks, like the Index Model or the Zachman Framework. Investigate these similarities. Is there compatibility? Can the work done in ITIFs be used to further the development of PCM?

Overarching Concepts


Goodness is often confused with quality, when in fact it is a more general concept (in engineering). Definitions of quality abound in the design engineering literature and they are mostly consistent at least in a general way. It is discussed as part of PCM because it is not only a concept applying to designed products and processes, but to the models, methodologies, theories, and logics that are used to formalize product models and processes.

To emphasize the difference between goodness and quality, consider that a good product is of both high quality and low cost. But high quality does not necessarily imply low cost per se, and vice versa.

But goodness is different, in that it makes no commitment to particular metrics the way that quality does. When one attempts to make something good, one implies (a) that there do exist characteristics that intentionally define good items, (b) that there is a method by which goodness is measured, and © that achieving goodness is always the fundamental goal of a development process.

Open Issues

  • This section needs to be expanded. What are the basic requirements to be met by something that is good? Who's the client? What's the goals? What implementation strategy, technologies, etc. are to be used?
  • What are the “overarching concepts” here?

Engineering Sense

Much of the research in logic, especially in areas like mereotopology and spatial reasoning, seems devoted to capturing “common sense” ideas about parthood, connection, and other relations between things. The problem is that common sense - the sense typical of the average person - is not reasonable in an engineering environment.

This is not to say that engineers require the most realistic, physically verifiable sense. Engineers do not (yet) care about quarks, or dark matter, or of spaces of more than 4 dimensions. Nonetheless, they require a far stricter perspective than that of the “common folk”. We are often interested in molecular and even atomic effects, and in maintaining a physical sense that takes into account the macroscopic behavior of materials that may be seen as counter-intuitive or bizarre by the common folk.

This “engineering sense”, then, sits somewhere between the rather lax sense of the common folk, and the very strict sense required by the natural sciences. Since engineering sense is not a guiding theme in the development of many of the foundations upon which this research builds, the Design Logic will have to re-interpret and, in some cases, re-develop components of the underlying logics, to remain consistent with engineering sense.

Open Issues

  • What are the characteristics of engineering sense that distinguish it from common sense?

See Also


[Sal95]. F. A. Salustri. 1995. An Artifact-Centered Framework for Modeling Engineering Design. In Proceedings of ICED 95, 10th International Conference on Engineering Design (ed. V. Hubka); Heurista, Zurich. pages 74-79. (link)
research/product_centred_modelling.txt · Last modified: 2020.03.12 13:30 (external edit)