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switchlanez · 08-17-2013, 04:37 AM

@nalc's questions may seem smart-ass if they all go over your head but they're really not smart-ass at all. They are objective, intelligent questions that pursue truth, not negativity. But I'll argue that his aerospace engineering way of thinking (where tolerances are of utmost importance) may be a tad out of place. That world is literally rocket science, whereas automotive engineering isn't. Applying the same levels of R&D/dev testing may be overkill.

I'll wager a guess that there are some universal points at which this unibody chassis can benefit from bracing. Examples: Front/rear stabilizer bars or the stock V-brace in the engine bay. The V-brace shall go from the strut to the center of the firewall, there's not really much wiggle room to design it any other way. But how would they know to apply it in the first place? Perhaps the proof of concept has been proven over and over again/immortalized within structural/automotive engineering circles. No need to reinvent the wheel. To be thorough, the OEM may have used a strain gauge to validate the decision. Or not, because that might be like doing integral calculus then taking the derivative of your answer to prove it (an academic exercise).

I'm no structural engineer, but I imagine they adhere to some common truths in rollcage fabrication to get it maybe 80% to 95% accurate towards being optimally functional. That last 5% may require extensive computer modeling and hundreds of thousands in resources/fab/adjust/verify/re-fab/readjust/verify/refab, etc. just so they know the perfect mounting point down to the millimeter and perfect bend angles to the tenth of a degree. But 95% accuracy may just require a tape measurer+protractor across critical points of the unibody and basic application of geometry/structural principles. I imagine it to be a plug-and-chug deal. Otherwise, thousands more dollars to squeeze out that last 5%? Ain't nobody got time for that.

Skip to 3:50 for quick clips of a Chassis Design Engineer fabricating a one-off rollcage for Toshiki Yoshioka's Formula Drift BRZ. The work he does appears to be a routine, unsophisticated deal for him:
[ame="https://www.youtube.com/watch?v=KSS9l4yjjbg"]The HANDICAM DIARIES: GTNET TOMEI BRZ- Episode 4 Picking up the Pace (re-upload) - YouTube[/ame]

08-17-2013, 04:37 AM	#25
switchlanez Glorious BRZ Master Race Join Date: Apr 2011 Drives: Subaru Libird Location: Race Wars Posts: 3,645 Thanks: 1,050 Thanked 2,719 Times in 1,079 Posts Mentioned: 110 Post(s) Tagged: 0 Thread(s)	@nalc's questions may seem smart-ass if they all go over your head but they're really not smart-ass at all. They are objective, intelligent questions that pursue truth, not negativity. But I'll argue that his aerospace engineering way of thinking (where tolerances are of utmost importance) may be a tad out of place. That world is literally rocket science, whereas automotive engineering isn't. Applying the same levels of R&D/dev testing may be overkill. I'll wager a guess that there are some universal points at which this unibody chassis can benefit from bracing. Examples: Front/rear stabilizer bars or the stock V-brace in the engine bay. The V-brace shall go from the strut to the center of the firewall, there's not really much wiggle room to design it any other way. But how would they know to apply it in the first place? Perhaps the proof of concept has been proven over and over again/immortalized within structural/automotive engineering circles. No need to reinvent the wheel. To be thorough, the OEM may have used a strain gauge to validate the decision. Or not, because that might be like doing integral calculus then taking the derivative of your answer to prove it (an academic exercise). I'm no structural engineer, but I imagine they adhere to some common truths in rollcage fabrication to get it maybe 80% to 95% accurate towards being optimally functional. That last 5% may require extensive computer modeling and hundreds of thousands in resources/fab/adjust/verify/re-fab/readjust/verify/refab, etc. just so they know the perfect mounting point down to the millimeter and perfect bend angles to the tenth of a degree. But 95% accuracy may just require a tape measurer+protractor across critical points of the unibody and basic application of geometry/structural principles. I imagine it to be a plug-and-chug deal. Otherwise, thousands more dollars to squeeze out that last 5%? Ain't nobody got time for that. Skip to 3:50 for quick clips of a Chassis Design Engineer fabricating a one-off rollcage for Toshiki Yoshioka's Formula Drift BRZ. The work he does appears to be a routine, unsophisticated deal for him: [ame="https://www.youtube.com/watch?v=KSS9l4yjjbg"]The HANDICAM DIARIES: GTNET TOMEI BRZ- Episode 4 Picking up the Pace (re-upload) - YouTube[/ame] __________________ << BUILD THREAD >> Last edited by switchlanez; 08-17-2013 at 04:49 AM.