Sonic Shifter vs. Super Shifter

[xForceDee]

I recognize that the sonic shifter just came out but I was wondering what people's opinion were as to how it stacks up to its predecessor the super shifter.

[DonRotolo]

They took the lessons learned and made improvements. What more can one want?

[BrendanB]

Its nice to see more options available to teams and how this gearbox on paper shows improvements to the SuperShifter. Lighter, centered output shaft, more gear ratios, etc make me excited to hopefully use it in a prototype drivetrain this fall.

[Pault]

There are some nice improvements in there. I was a bit underwhelmed, but the supershifter is a such great product already, so I really couldn't ask for much more.

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.

The CADer side of me loves that the output shaft is centered, but the normal* side of me is thinking more along the lines of "meh".

I do like that the sides are open now. Could make it easy to apply more grease and do other maintenance, plus I think I see potential for a PTO (although teams who can do a PTO are probably more likely to just make their own gearboxes).

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. 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.

*The term normal is relative to CADer side of me. When compared to the rest of society, there is no normal side of me.

[Brandon Zalinsky]

Does anyone have a link to these? I can't seem to find it.

[Boe]

Originally Posted by Flak-Bait

Does anyone have a link to these? I can't seem to find it.

http://www.andymark.com/product-p/am-sonicoptions.htm

[Brandon Zalinsky]

Those look pretty nice. I'd be interested to see how the open sides work for teams, whether the weight reduction and ease of maintenance outweigh the possibility of unwanted debris. I've never been on a team that uses open gearboxes, but I'm sure that many teams use them. Any opinion on that tradeoff?

[BrendanB]

Originally Posted by Flak-Bait

Those look pretty nice. I'd be interested to see how the open sides work for teams, whether the weight reduction and ease of maintenance outweigh the possibility of unwanted debris. I've never been on a team that uses open gearboxes, but I'm sure that many teams use them. Any opinion on that tradeoff?

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.

[Brandon Holley]

Originally Posted by Flak-Bait

Does anyone have a link to these? I can't seem to find it.

We've built and used "open" gearboxes in our drive trains for as long as I have been on the team (going on 9 years). While I was on team 11 before that we used open gearboxes in the drivetrain. I can't say I ever had an issue with debris causing a failure in the gearbox.

One advantage to the closed gearbox IMO moreso than keeping debris out is that it keeps grease in...However thats more of a minor annoyance than a critical design criteria.

-Brando

[Boe]

Originally Posted by Flak-Bait

Those look pretty nice. I'd be interested to see how the open sides work for teams, whether the weight reduction and ease of maintenance outweigh the possibility of unwanted debris. I've never been on a team that uses open gearboxes, but I'm sure that many teams use them. Any opinion on that tradeoff?

2175 has been using open gearboxes for the last 2+ years and we typically get a sheet or two of overhead projector paper and cut it to size to wrap around the gearbox to keep debris out. It is extremely simple to do and weighs practically nothing.

[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!

[Pault]

Originally Posted by Nathan Streeter

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...

Ok, thanks. I had a feeling that I overlooked something, it just isn't like AndyMark to try and trick people into thinking there was some big improvement when really it was nothing significant. This makes sense.

Originally Posted by Nathan Streeter

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...

Yea, I think this is where a difference in strategies come into play. Your team was a full court shooter and potential cycler, so you really had no reason to slow down unless for those special scenarios. My team had a floor pickup, so we actually spent the majority of our time in low gear because we needed more precision driving work. It also didn't help that we had trouble turning in high gear. However, we had high gear in there if we needed to get to a far away disk, or if we ever decided to cycle. Although actually, I didn't really realize that as you go down to lower speeds in low gear, you get fairly low high gear speeds. 4fps low makes a little over 10fps high gear. So on second thought, maybe the spread is fine after all.

[apalrd]

We've always used the Gen 1 AM shifters or similar design when using chain as the final drive since we don't need the third gear stage. We used the SS stock to direct drive 6" wheels in 2011 and were happy, with gen 1's in 2010, 2012, and 2013 and were also happy (with the shifters, not necessarily our gear choices). In 2012 we made a cover to keep grease out of the cRio (it was in line with the gears), and removed it before the first competition for weight after the transmission stopped flinging grease. No issues with stuff getting into the gearbox, although we did get a large chunk of ball in a chain in 2012.

I too would like a lower ratio spread option. It's really all about what your gearing objectives are, how you want to play the game, and how open the field is, but I personally would like something on the order of 1.8:1 spread

[GDG 2337]

We’ve been using open Gen 1 shifters for last several years and have gone away from traditional grease to a dry open gearing spray lube.

I sent Andy a note earlier in the year about offering an 18/45 low gear set for Gen 1’s and Super Shifters. We were looking at less of split between high and low for this year’s game. Gear set would provide a faster low providing a 2:1 instead of 2.56:1 or 3.13:1 instead of 4:1.

AndyMark already offers 45 tooth gears, just needs the 18 tooth gear stock.