> How long does it take to do a computer simulation to check that something 
> won't break? How complicated is the process, and how much computer time 
> does it take?

That sort of simulation is very quick and easy, only a few hours for a 
moderately complicated part and then you get back data about the stress at 
every point.

The harder simulations are the ones where you want to actually simulate some 
dynamic force (like your product being dropped on the floor) and then of 
course the simulator needs to deal with collisions and deformations.  These 
sorts of simulations can take a long time to set up and run for days just to 
simulate a fraction of a second.

> So... corrugated? Or something.

On the one I worked on we just bolted the base of the display to the car, 
and then had two hooks at the back half way up that hooked into the car 
mechanics (no screws).  That way when you pulled forward on the display the 
hooks provided the strength and stiffness, and if you pushed back the hooks 
did nothing so you were free to bend the bottom fixing points if you hit it 
hard enough.

> Heh, yeah. I guess if you've made something similar before it helps a lot. 
> ;-) I was just thinking, I imagine for "most" manufactured items, the 
> designers probably have a basic intuition about roughly what thickness of 
> metal is required. I don't suppose they do an exhaustive mathematical 
> derrivation of optimal thickness for every single component ever designed.

It depends on the product and how critical it is, plus how many you are 
making.  For something you are only making 1 of, like a bridge or a big 
building, you will probably do a lot of calculations.  If you are planning 
to make 10 million of something, you can probably just make a few hundred 
test samples and have chance to optmise them if needed.

> Right. So you take an educated guess, and if the prototypes fall apart, 
> you figure out which bit broke?

Yup, for car parts we usually have 3 rounds of prototypes before mass 
production starts.

> Almost every platform known to man already has a C compiler - even if it 
> has nothing else. The C compiler is typically the very first thing that 
> gets built. ;-)

Someone still has to build it though in the first place.

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