By Dr. Joel Orr
Only connect! That was the whole of her sermon. Only connect the prose and the passion, and both will be exalted, and human love will be seen at its height. Live in fragments no longer.
"Howards End"E.M. Forster
- Requirements capture
- Conceptual design
- Detailed design and refinement
- Prototyping and refinement
- Design approval
- Production process design
- Deployment and support
This linear list is very neat, but reality is not so. The actual track of a product design process over time keeps looping back to earlier steps, with lots of corrections and retracing.
Why is it so messy? Because design is not deterministic; that is, there is not a single optimal design that emerges from a given set of initial requirements. It is, rather, a process of trial and error. A lot of learning happens along the way; the project team makes discoveries on many fronts of things that were not known when the project began: Properties of materials; how things work together; actual customer needs; emergence of other products; and many other pieces of information pop up in the course of a design project to affect the design.
The world moves on, and you can't step into the same river twice. All this novelty is inevitable, and hence it is unlikely that the fundamental process of engineering will change.
However, there are aspects of the process that can be improved. In particular, while the tools are available today to do so, information from one stage of the process is seldom communicated to subsequent stages, except in the form of a final result. That is, the list of requirements created in the early stages is seldom intact, let alone examined, by the time the project reaches the prototype phase. Important information such as decisions made, and the rationale for them, is seldom retained.
This situation leads to a host of inefficiencies:
- When you don't know why something was done, you may inadvertently make changes that could adversely affect the product or its performance;
- More resources are involved, the further along the process you go. So correcting a problem earlier in the process is much cheaper than correcting the same problem later. Yet if you lose track of requirements, the problem may not be evident until later, when it's more expensive to fix;
- Good ideas pop up at various times during the design process. But unless you are able to gauge their impact, it's difficult to tell if they are worth implementing;
- If you are not maintaining information within a given project, you are surely not maintaining it from project to project. That means you keep "reinventing the wheel" at best. If the personnel who worked on one project are no longer available, their knowledge is gone with them, since the decisions and the reasons for them were not recorded.
But if you are organized to preserve information throughout the engineering process, you avoid all of these problems. Moreover, as time goes by, you and your organization get better and better at design-because you have access to everything that went into earlier designs.
So you are able to reach the end of a given design project with a product that meets or exceeds the original requirementsand you are able to produce an even better design on the next project. And this is without regard to whether the same people are available to work on it!
The fact is that very little thought goes into preserving the integrity of all the knowledge and information that goes into an engineering project today. It's preserved more-or-less piece-wise, without integrity. Ultimately, there is a bill of materials stored in a PDM (product-data management) system-without history, without rationale, as though it appeared out of nowhere.
Think about it. Strategize a way to begin to track information in your engineering projects, starting with requirements, and extending through to manufacturing. Search for new software tools that may be addressing this challenge. The cost to implement such things could turn out to be very lowand the potential rewards are huge. Find a way to connect the "prose" of documentation with the "passion" of the design process.
is an author, consultant, and public speaker. He consults to Fortune 500 companies, high-tech startups, and government agencies on CAE issues. He is the founder of the League for Engineering Automation Productivity (LEAP) and has been an Autodesk Distinguished Fellow and the Bentley Engineering Laureate. A long-time Computer-Aided Engineering columnist, in the CAD/CAM Monthly e-mail newsletter, Dr. Orr will continue with his reflections on all aspects of engineering. Contact him at [email protected] or visit his Web site: www.joelorr.com