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Unread 06-01-2016, 08:25
BoilerMentor BoilerMentor is offline
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Re: Sonic Shifter - recent feedback?

Quote:
Originally Posted by waialua359 View Post
However, I would respectfully disagree on the automatic shifting. We tried it in 3 different seasons and will never ever go back to it. In every instance, it failed/or started to wear heavily on some parts causing shifting problems. We got tired of the constant checking and paranoia that it would fail in a match.
Based on my conversation with Paul via email, I'd agree with the assessment that the press fit between the shifter shaft and the hex output shaft was the issue. I'd like to believe that with either the upgraded shaft, or our revision with the shaft being supported by a bearing opposite the gear we wouldn't have seen the failure in competition.

I'd be very curious to hear what those failure modes were with auto shifting and if there's anything I can add to that conversation. We implemented a power cut in the shifting routine that made a world of difference in testing and I suspect would significantly decrease .

I've been preaching autoshifting very hard given the fears about brown-out and the testing results we achieved with the robot in question in this thread from 2014. If the game warrants six cim two speed drivetrains this year, I suspect we'll see dozens of matches with dead at least one dead robot because of the brown out issue. I'm fairly confident, based on our experimental data, that a six cim shifting drive will brown-out if a drive accelerates aggressively from a stop.
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