Electronic Prototyping and 3D Modelling

04 Mar

There is much in the press about BIM and digital engineering at present so I thought I would contribute to the technical scene this month with a viewpoint on electronic prototyping and 3D modelling.

More and more engineers are turning these days towards computer numeric modelling and FEA. I have to admit that I am a bit ambivalent about it all. On the one hand, these are powerful tools capable of modelling complex scenarios and achieve incredibly accurate results in rapid timescale. But I have also witnessed first hand, how a slight change in the settings, support and restraints, a little trick of mathematics or simple misinterpretation of results can utterly change the outcome of an FEA simulation. Interpreting the results of course is vital in understanding what is actually happening and how the structure is behaving. It is also a bit of a black art!.

In the end and vitally importantly it still comes down to applying that indefinable quality of engineering judgement. No matter how clever and complex or user-friendly the software is, there is simply no substitute for having a well rounded, competent engineer at the steering wheel. With this in mind, I’d like to share with you a relatively simple example of our electronic prototyping and FEA modelling experiences.

Above is a simulation of a simple “gallows bracket” welded to sheet piles, supporting a horizontal beam represented by the yellow arrows. This simulation shows how the stresses are distributed throughout the bracket and can give an insight into the potential modes of failure. Again, this is all reliant on having the expertise to interpret this data.

You can see from the “rainbow” of stress that the areas that require the most attention (shown red), are the welded connection at the top rear of the fabrication, the gusset plate and lower part of the web of the UC section. This type of analysis proves itself time and again to be a useful tool, not perhaps so much to directly verify the final design, but more perhaps to highlight areas of the structure that need further investigation and possible strengthening and also to help our engineers develop the design into the optimum format by taking material out.

We have started using this 3D prototyping process to increase the strength and reduce the weight of our new developments. Of course, the final design is always backed up by good old fashioned manual or at best software assisted calculations. This process is perhaps a modern variation of what used to be termed “design assisted by testing”.

Moving on from this, we have recently invested in a state of the art 3D printer. It does take a bit of setting up and upwards of 30 hours to produce a high quality prototype, but you can see the results for yourself. Being able to handle the final object (albeit a scaled down version) really helps us to visualise how equipment will work in the field. Perhaps at some stage in the future, these little models will become much sought after collectors’ items for the cognoscenti!.

In the next blog, I aim to be talking about how these developments have helped us to design the next generation of high capacity equipment; bet you can’t wait!