"Make everything as simple as possible, but not simpler" - Albert Einstein
As you have likely determined from the sequencing of our section headers, we drive our process from simple to complex -- starting with simple models and engineering calculations and building up from there.
Projects ranging from simple analog devices to sophisticated electro-mechanical medical instruments all start from the same foundations in physics. That's why we try to break things down to the simplest principles early in the development cycle. This includes extensive use of engineering calculations by hand to get our heads around the fundamental physics at work.
At the heart of all numerical simulations lie the fundamental laws of physics -- whether one executes these by hand, with a spreadsheet, or via engineering calculators -- the fundamental governing principles remain unchanged.
All of our engineers are well versed in engineering calculations: we have decades of combined experience, most of our engineering consulting team members hold advanced degrees and all are well versed in CAD. Nonetheless, we rely daily on our foundational knowledge of physics and the engineering calculations it brings.
While computer-based simulations and numerical engineering calculations have come a long way, the reassuring value of a simple (or sometimes not-so-simple!) hand calculation is indispensable.
In one recent incident our team fell back on basic engineering calculations to account for a material’s non-linear behavior; providing real, logical bounds to a problem which would have proven time-consuming to do computationally.
Although modern computing power can solve complex systems of equations in the blink of an eye, they can also make errors and produce nonsensical results just as fast. The old adage of "Garbage In, Garbage Out" holds true.
Competent use of the computational power we have at our disposal in mechanical engineering requires a rigorous understanding of its function, its premises, and its limitations. In addition, we must correctly interpret the results of these calculations.
While computer simulations and mechanical engineering calculations most certainly have their place, the simplicity and speed of a humble hand calculation can, in most instances, take us 90% of the way towards a solution.
More sophisticated tools for mechanical engineering calculations are covered in other sections of this site. As you’ll see, we are very skilled in their use but mechanical engineering hand calculations can get us in the "ballpark" faster and tell us if further, more rigorous, analysis is required, or if we're headed down the wrong road.
These hand calculations constitute a universal language of mechanical engineering which is not subject to interpretation or limited by what CAD package you or your client might be running. As such they play a duel role in our consulting practice: they’re fast and help to leverage centuries of practice and understanding to communicate concepts to our mechanical engineering colleagues.
And if further engineering analysis is indeed required, we now know with certain confidence what to expect -- which serves to build confidence in our engineering calculation tools and allows us to push them further than we may be able to go "by hand".
Recalling a recent project, our engineering team was able to quickly determine the loads and forces acting on a mechanism to determine a worst case scenario instead of investing the time to build a simulation which would require specific information (such as friction!) not yet available to us to even begin execution. Hand calculations put us in a position to continue working towards a sensible solution until better information was at hand – and even then, provide us with reasonable expectations of what those simulations would tell us.