Andymark Churros

[Nathan Streeter]

Originally Posted by hrench

I also want to weigh-in on the 'build it and see if it breaks' philosphy that's being encouraged here.


That is NOT SCIENCE. What Science IS is using previous observation to determine what will happen deductively. The reason we engineers make books of statistics about materials and books of equations about stresses is because science works. If we design something that will work because we've used science, we've taught the kids the value of STEM.

if we design something with the guess that it might break or might not, then we didn't teach math, we didn't teach use of historical empirical statistics and instead we've taught 'trial and error.'

Not a good way to be an engineer.

I'm also going to agree and disagree...

I agree that good engineering inherently should involve calculations/FEA/CFD/'running the numbers,' and that if we shield our students from that entire side, we're giving a poor image of what good engineering is.

However, we'll also be very poorly teaching students if we hand students a single equation for torsion or bending and a table of material properties. In FRC, far more dangerous than testing something (being unsure of failure or success) is the attitude that the equation or FEA is a magic box that spits out a highly accurate solution. Quite frankly, Mechanics/Fatigue/Failure/Stress Analysis are complicated and tedious enough that if we took the time to truly 'run the numbers' for 5% of the bearings, shafts, gears, keyways, fasteners, and frame members we'd be entirely out of time! Much of my Mechanical Design class was spent doing just these calculations for a single loaded axle with gears, bearings, keyways, and fasteners... accounting for the impact of keyways, stress concentrations, cyclic loading, reliability, factor of safety, etc. is very tedious, generally requires iterative calculations, and even then fails to really include the effect of heavy impacts.

Quite simply, it's best to teach students some mechanics of materials, materials science, and mechanical design, but it's also good to teach them that Engineering is saving time with some simple calculations, understanding the significant short-comings to theoretical tests, setting up a good physical test, predicting the success of a component from prior experiences, and knowing when to 'just try it.'