and a lazy way to do calculations. The Educational edition of Solidworks has the full-on CosmosWorks designer built in to it, and FloWorks, but I'm fairly sure I don't have enough processor cycles in my PC to sanely do any meaningful CFD studies. I thought I'd check out the possibility of integrating the body-side mounting of the heave spring into the big lump of metal that slides from side-to-side when the car rolls. A quick analysis later (and it took less than a minute to cue it up and run it - far, far better than when I used to use FEA in the days before Pentiums - I first used PAFEC on a Vax and IBM CAD on a mainframe) and you get the picture above. This is the von Mises plot, which is effectively a combinational stress criteria for yield (if you get yield when you combine the stresses in all three dimensions using the von mises formula, it'll probably yield in real life) when 5000N (a bit more than 500 kg) of loading is applied to the bolt hole. If you click on the drawing you'll get a better view, but the safety factor (i.e. the ratio of actual stress to peak stress) is just over three, so even if shock loading was applied, you'd still not cause that lump of metal to yield.
So, knowing that I'm not overloading the lump in question, I can clean the design up a bit, which gives the picture you see below:
I've shortened the guide rails as much as possible (I'll be running the geometry again to see what motion ratios I have and how much roll travel I actually need) to limit the bending moment on them and put a simple framework around that can be bolted onto the chassis in the most appropriate place. I'm now almost ready to start designing the chassis. Adrian has offered to let me measure his bodywork, so I know what space I have to play around with, and I've got a copy of the Blue Book to tell me what I can and can't do, so I'll start with the rollbar and go on from there.
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