The importance of the human factor

The spread of FEM analysis as design and simulation tool for mechanical components has been enabled by the contemporary development of codes and software which made it available to most users, with their calculation power and simpleness.

But are we sure that pressing the run button is all you need to do?

It is pretty much known to the insiders that FEM Analysis is able to reproduce many physical phenomenon through a series of simulations on a computer. Mechanical components can be stressed statically and dynamically, deform to loads and heat exchange, interact with liquids, gasses, magnetic fields and much more, all inside a powerful virtual lab.

Its potential, together with increasingly high-performance hardware and increasingly User Friendly software interfaces, has allowed the FEM analysis to carve out a place inside the product development cycle.

However, to such simplicity of use and calculation power, there is a certain danger, dictated by the familiarity induced by the instruments themselves. Most FEM software can always produce a result, unless the calculus is very badly set up, and the analyst can be lead to unconsciously trust its outcome unless the software itself point out to evident errors.

In the face of an apparently simple and constantly guided procedure, it is not at all difficult for the operator to blindly trust the instrument

It is not rare, in fact, that poor choices when modeling the system, lead to completely incorrect results.

The analyst therefore has the important task of modeling the mechanism that is intended to be simulated within the FEM environment, by correctly modeling constraints, ground connections, connections between components, external factors like forces and temperature, and finally by choosing the right solution algorithm, as well as the size of the appropriate FEM element and time step. This topic is probably the most controversial: in FEM calculus, space and time are not continuous entities, but become a succession of points, and the question is how far between these they have to be.

In the first instance, it would be spontaneous, not to be mistaken, to insert all the physical quantities that are known indiscriminately into the FEM analysis, even though some physical quantities are irrelevant for the result. Or again, use a very thick mesh. This way of proceeding, however, would inevitably lead to an exponential increase in the calculation time, with a consequent increase in man / machine hours and costs, without a real benefit for the analysis.

The analyst’s task is therefore to find the right trade-off between calculation time and system accuracy.

Which translates in a cut in costs for the operators, and its customers.

Phi Drive is at the top of the list in this task, being able to count on calculation codes and cutting-edge resolution strategies developed over the years. Bearings, kinematic mechanisms, sliding blocks, recirculating ball guides, rotating component can be correctly modeled with the use of our tools. The ability to interpret the results then complete the work, allowing Phi Drive to respond promptly to all customer needs.

Do you still trust anyone who press the “ run ” button???

Paolo ROBERTO