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Comment: Not really... (Score 1, Interesting) 649

by Grog6 (#49514803) Attached to: Automakers To Gearheads: Stop Repairing Cars

I own three cars that I regularly work on.

I have tuners and tuning software that allows me to write my own set of parameters to run the car by.

The learning curve is hard, benefits are low unless you are constantly tinkering, and the cost of entry and training is pretty high.

I do not think Ford gives a rat's ass about my activities; my cars are too old to be on their radar.

None of my cars are Fly-Bt-Wire.

I have Real Brakes, Real Steering, and Real throttle action. Not going to say those won't fail, but they are a well proven technology.

I've reprogrammed all three cars to match various modifications, engine swaps, etc. It takes changing computer tables/values to get everything working well together.

This kind of "Programming" is more like changing the build file and recompiling with new values; you are not changing structure, just INI files, kinda.

I can't conceive of a circumstance that a bad ini file could cause a problem in the program structure... lol.

That said: In no way would I ever tinker with a FBW computer; the factory code could Crash my car from a WOT throttle event or some such shit Stock, without any help from me.

If you haven't read it, search out the settlement to the Toyota problems; the code review (postmortem, no less) was brutal.
They violated pretty much every rule I know for real time code; and didn't even realize they were having intermittent stack overflows.
They thought they were using a few stack locations; one routine used 30+, lol.
They didn't go to jail; a normal citizen would in a heartbeat.

They also don't want anyone dicking with their "InfoTainment" revenues; if your car has a cellphone, it's talking about you. :)

Comment: Re:You Can See (Score 1) 113

by Grog6 (#49490497) Attached to: An Engineering Analysis of the Falcon 9 First Stage Landing Failure
I really didn't see that as a thruster fuckup. I saw the gyros overshoot, the control system forget or be confused about where "UP" was, Land, and then eventually let go. Gyros often overshoot during high delta-v operations; the bearing load changes randomly and extremely. 10g's of vibration, 1mm in length will change a bearings properties amazingly. (For an extreme example of the effects of vibration, look up "POGO effect" as it related to the Saturn V rocket. :) This may be geek sniping, so beware.) It may have been confused by the burn vibrations, and delta-v problems; there's a lot of shit going on at the end. The thrusters were doing what they could, but given the attitude it thought UP was at the end, and that it looked like they weren't taking gyro precession into account, it looked like it fell over when the gyros hit their limits. "Eh, this looks good to me, why are all you guys going apeshit?" If it doesn't use Gyros for attitude control, I'd suggest they might help. But in that case, SpaceX's Control software is even more freaking awesome. :) I hope the next one works!

Comment: Re:unreal (Score 1) 291

by Grog6 (#49452793) Attached to: Cannabis Smoking Makes Students Less Likely To Pass University Courses
Agreed; video games, and all the time I wasted chasing "Hot Chicks", who are now aging trailer trash, lol. Notice I said 'chasing'; this Is /. :) About the article, tho: I found out during high school that I couldn't do Calculus while stoned; it was something I had to work around back then. Eight hours of sleep would clear it right out... Not so much a problem anymore; and I still do Calculus daily. :)

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