Sonic Shifter vs. Super Shifter

[Nathan Streeter]

Originally Posted by Pault

It's nice that its lighter, but I think it only shed .2lb, so that won't make a huge difference in the grand scheme of things.

I think it's actually about .65lbs per gearbox... The SuperShifter says 4.0 per gearbox without pneumatics or CIMs. The Sonic Shifter says 3.8 with pneumatic cylinder, 3.35 with just the pneumatic mounting bracket. Doing the apples-to-apples comparison, looks like a weight loss of .65#... which when you include the two gearboxes is a relatively noteworthy 1.3 pounds. Also, looks like the servo shifting is at least 1 pound stronger, so that may make servo shifting more reasonable...

Originally Posted by Pault

The additional gear ratios was a much needed improvement. It annoyed me that I actually had to use chain to speed up the drivetrain, rather than slowing it down like with most gearboxes. Now I can just get a lower ratio version and slow it down like normal. It could even be used for direct drive if teams wanted to.

Yeah, that was a big frustration of mine... the fact that it geared down more than most FRC teams would like. I love the fact that it has 4 different gear ratios for the 4:1 spread and the 2.56:1 spread! The table with adjusted fps speeds is also pretty great... :-)

Originally Posted by Pault

My biggest complaint is that they didn't add an option to get less of a spread between low and high gear. This year my team did 6fps and 15.38fps, and although it worked out for ultimate ascent, I'm not sure that I would like such a big difference in speeds for most other games.

I'm not really sure that a smaller (than 2.56:1) spread is preferable... I actually think the 2.56:1 spread is too small (although I'm not totally committed to the 4:1 spread); however, it really depends on how you use your gears.

I generally think that your high gear should be what you use most of the time, occasionally switching over to low gear for pushing, traversing field elements, and maybe some careful alignment. When you're only using low gear for these things, it's hard to have a low-gear that's too low. 1519's low gear has been in the 2.5-4 fps range the past two seasons... which initially seems ridiculously slow, but it's actually quite good for those three tasks I mentioned. I would've preferred we use the 4:1 spread so our high gear wasn't underwhelmingly slow though... particularly this year: when we'd switch from FCS to cycles or defense we'd just take too long to get from point A to B!

At any rate, different game strategies should probably lead to different high and low gear preferences...

Originally Posted by BrendanB

With the old design you could lose at least a 1 pound replacing the plastic case with spacers. To combat random debris we took some 1/32in. lexan and bent it around the gearbox and secured the ends with Velcro. It allowed quick visible access to the gearbox when needed and the only time we had a problem with that gearbox failing a few weeks ago we were able to service it without taking it off the robot because we had access.

I definitely think 1519 will be trying this out... the old case was definitely heavier, but I'm guessing we could still get ~1 pound weight savings if we do this with both gearboxes. Definitely has the "debris out, grease in" advantage while offering extra ease of maintenance... that and I'm sure safety inspectors prefer it!