Avoiding Pitfalls in Digital Prototyping

The first pitfall to avoid is trying to re-invent the wheel, an error committed by the author in lead to his second paragraph, where he states:

"Revolutionary designs are the inventions that can change the way we live. They are... and the electric car..." Which totally ignores the fact that 100 years ago, electric cars outnumbered those powered by other means, at least in the US. Returning to past failures does not constitute revolutionary design...

...but looking at how modern technology can reduce or eliminate the main problems encountered "back then" can give these older technologies a new lease of life.

GM1964-

Very true, but, in the particular case of the electric vehicle, the advocates seem to ignore the history, especially why the IC engine became the power plant of choice. Furthermore, changing the power plant is not going to have a major impact on how people live their lives...

new lease of life?

You do nothing unless it is economical advantage or only way left over to survive. You can also have multiple ways to use the resources in whatever technology one knows that otherwise may never be used. These are done at small level and do not become real technology of time for many. Creating something for museum is different than things meant for real life.

There have been a number of projects lately which involved significant capital expense to produce copies of historic technology.

One of these is a steam locomotive, built to the exact specifications of the original. With the time and effort put into the project, I wonder how much more efficient the end result could have been had the latest techniques, materials and tolerances been employed - is there a case for the return of steam locos, even if the heating is provided by electricity, gas or diesel?

Another is a water wheel, attached to a millhouse which has been converted to a youth hostel. Original equipment was sourced at great expense and the wheel is only operated occasionally, as the maintenance is expensive and time-consuming. I would have preferred to see sealed unit bearings encased in an original-looking carrier, and an electric generator used to constantly provide the power for the hostel.

While each is a major achievement for the groups involved, use of digital methods could have given an end result which was aesthetically identical, but a significant step forward in the actual design.

I laud efforts such as those you cite, rebuilding a steam locomotive or the water wheel- it is very important to me to preserve an understanding of the revolutionary accomplishments humans have achieved over the millennia. However, i find it a real stretch to think that a steam locomotive, where one is incorporating a material phase change between the extraction of energy and the application thereof, would ever be more economically viable than current diesel-electric locomotives. Your example of the water wheel brings up a very good point, in that this older technology, while important to understand, is maintenance-intensive- I suspect that would be true even if one used sealed unit bearings. Furthermore, unless this water wheel is sitting in a really strong flow, it is unlikely that it would be able to provide sufficient power for a typical small modern hotel, although it might prove useful for supplementing other alternative energy sources. And, if it sat in a sufficiently strong flow, the maintenance costs would be even greater...

I can offer up an even better example of wonderful past engineering accomplishments, right here in Panama, where the Canal continues to operate using equipment that was built over 100 years ago, still functioning and handling a flow of traffic that the original designers never dreamed would be possible.

Preserving history, studying the accomplishments of our ancestors, is an important endeavor, but it is not life-changing, revolutionary development...

To be honest, I believe that the "life-changing, revolutionary development" that we see is usually the result of many small step-changes - and a great deal of trial-and-error by the development teams.

I work in a field where manual operations are the norm, and the advent of mechanisation is a shock to the system - but often required due to lack of shut-down options.

Introducing RS485 CCTV is meeting resistance due to the "complexity" of the devices.

What is run-of-the-mill in one industry can still be revolutionary in another.

Learning is always very valuable. You get new ideas on the way due to ++ technology on hand. Even junkyard ideas are worth. You never know what will be the next new ideas. Even toilets for new aircraft designs are reinvented each time you wish to make it a bit better.

Go back and forth in time and get ideas polished each time and come up with something interesting story. This is true engineering which has no bounds.

Actually, I consider a junk yard one of the most inspirational environments I can imagine (you ought to see the back room of my shop!)...

But, then, very little of what I do these days can be considered "revolutionary" or "life changing"- except with what I do with domestic water systems (life-changing, not revolutionary)...

Actual work undertaken over the past five years or more in the 3D CAD prototyping as indicated potential risks of "virtual prototypes" over "hard prototypes".

Only by fully understanding the parameters of use of 3D modelling techniques is it possible to appreciate the true benefit of the technology available; for example simple structural elements are easily prototyped; however more complex machines are technically more involved, and require not only an overall assessment, but individual component assessment. Failure to appreciate the technology "will" result in disaster (early work in this area testifies this); however with experience and a better understanding of the 3D Prototyping systems "can" be beneficial in terms of time and cost saving; though ultimately the final product will need to be tested in the real world. Only then can you correlate the data between "virtual" and "hard". My personal experience has shown a growing trend to "avoiding pitfalls" through hard earned experience, and the design expert warning of such "pitfalls" is quite right to express the concerns and consider all aspects of the modelling process and not be "blinkered" by individual component analysis.

The future is undoubtedly 3D CAD design, but the transition will not be as swift as one might think, there are a lot of sceptics towards the new technology, and often focus on the "failures" rather than the "successes" (of which there are some very famous examples to those who are knowledgeable in such matters).

Simply jumping in the deep end is not advisable, it takes time and effort to develop the skills and experience necessary to utilise the new technology properly and effectively.

"Change is the law of life. And those who look only to the past or present are certain to miss the future." -- John F. Kennedy

An interesting article and I agree with all the points made.

However it fails to differentiate between prototypes and rigs specifically designed to test or prove sub-systems.

The word prototype derives from the Greek words "protos" directly translated as "first" and "typos" directly translated as "impression" In general usage a prototype is the "the first iteration of a design able to perform the required task". Subsequent prototypes are "the first to perform the task in an enhanced way" and so still retain the original meaning. A bicycle or a rail car will not go into a pipe so cannot be termed prototypes of a pipeline pig.

I would argue that this differentiation is more than just semantics. A software simulation is not a prototype, but it is valid tool in developing a new design. Sub system proving rigs fall into the same category.

I am not sure I agree entirely with your separation of individual items and the entire finished product.

I create sub-assemblies for an existing machine which alter or add to its capabilities.

To get approval for construction, I require to prove first that the individual components will fit, etc.

Even in the auto industry, each component will be upgraded (well, changed) once it has been proven - when was the last time a mass produced car came out with an entirely new body and engine? These are deliberately changed at different times to reduce the risk.

As an evangelist for 3D modeling since the early 80's, the hardest lesson I've learned about incorporating these systems into the design process is:

It's a tool, just a tool, that helps one get product to market. Relying solely on "digital prototyping" in itself will not get a product to market, be it a successful or mediocre design.

Ignoring any one of the many facets of product life cycle management is just as likely to result in project failure as any of the 5 pitfalls listed in the article. Rarely does the design process, in itself, result in product failure. In fact, ignoring any of the other aspects of the product life cycle can make the actual design process superfluous, if not a total waste of time, no matter the design tools or processes used.

I hope I'm making sense. I didn't get a lot of sleep last night.

Hooker