02-08-2016 13:19

asid61

Re: pic: 716 ouput shaft

Very interesting! That looks like a much easier way to maching a shfiting gearbox, without having to worry about using any indexer other than just a vise.
How much did you undersize the dog to fit into the dog gear? Were you able to shift on the fly?

02-08-2016 13:34

Andy Brockway

Re: pic: 716 ouput shaft

The full design is posted in White Papers. The square shaft is one of the upgrades in the 2016 gearbox. It shifts on the fly. 716 has used the square dog since 2005.

02-08-2016 14:12

Lil' Lavery

Re: pic: 716 ouput shaft

This invoked a trip down memory lane regarding the "old school" days of FRC shifting gearboxes. Aside of the DeWalt planetaries, only a handful of teams had shifting spur gearboxes in their drivetrains. The 116 crash shifter, the 33 4-speed crash shifter, the 222 ball shifter, the 45 dog shifter, the 716 dog shifter, etc. All of that barely more than a decade old. Newer FRC participants don't really how much of a game changer having spur gearboxes in the kit of parts was, let alone having COTS shifting options.

02-08-2016 15:57

ratdude747

Re: pic: 716 ouput shaft

The funny thing is that most/all of the older AM designs are mass-produced versions of 45's gearboxes... I hear before AM while there were KOP gearboxes they generally were junk in comparison. Hence why for many teams it was worth the little bit of machining to modify a dewalt or a lot of machining to DIY gearboxes.

Now days, it's more of an art than a necessity... although the summer/fall CAD threads show that people still think about it even if they don't always execute.

02-08-2016 16:23

Billfred

Re: pic: 716 ouput shaft

Hi, old-timer turned AndyMark employee.

The 2004 kit drivetrain is the only pre-modern "kit drivetrain" I got to experience. I emphasize the quotes, because the setup using Bosch drill gearboxes and custom unobtanium mounts and couplers left a lot to be desired. (Oh, and they expected you to weld the frame.)

The 2005-2006 kit drivetrain was a sheetmetal frame designed by a college student (John V-Neun, you might've heard of him) with a single-speed gearbox designed by Paul Copioli (you might've heard of him too). This was the first time you could order all the parts online in a non-obnoxious manner, through IFI Robotics. (The internal spur gears were sourced from an upstart company in Indiana called AndyMark.) The molded hubs on this drive system that clamped around the kit Skyway wheels (remember those?) established the 1.875" bolt circle as a de facto standard for FRC that remains today. (The cast housing and metric-sized output shaft on the gearbox? Not so much.) I don't remember when the original AM Toughbox came out, but I know we were evaluating it during the 2006 season. It became part of the Kit of Parts in 2009 and 2010.

But yes, the original AM Shifter does trace its lineage back to designs introduced by the TechnoKats. Many of the shifting parts have carried over to successive designs, even as things like external output shafts, servo shifting, room for more motors, and encoders have been added.

02-08-2016 16:43

asid61

Re: pic: 716 ouput shaft

Not to threadjack, but...
"skid plates"!? And that was a mere 12 years ago. It's incredible how far FRC has come.

02-08-2016 16:51

Cory

Re: pic: 716 ouput shaft

The 2004 setup was significantly less crappy than the 2003 one as well.

02-08-2016 16:53

ASD20

Re: pic: 716 ouput shaft

real skid-steer

02-08-2016 18:24

Sperkowsky

Re: pic: 716 ouput shaft

For a team wiyhout hex broaching abilities but with a lathe + mill a square shaft for some applications isn't a bad idea. I'll definitely keep this in mind.

02-08-2016 18:30

asid61

Re: pic: 716 ouput shaft

Keep in mind you would probably want a square broach for the dog, however. You might be able to get the dog 3d printed in steel.

02-08-2016 20:19

ratdude747

Re: pic: 716 ouput shaft

Yeah I should have clarified that I was mainly speaking of the AM shifter... as I among many others know the former technokat that designed it as a student on 45.

The tough box came out in 2008 KOP. 2007 had the same setup as 2006. I thought they were AM gearboxes because of common gears... I was obviously wrong.

02-08-2016 20:44

Cothron Theiss

Re: pic: 716 ouput shaft

Depending on where you are, wire EDM + post machining might be a cheaper and quicker option than metal Additive. But if you go that route, you might as well go hex.

02-08-2016 21:15

Billfred

Re: pic: 716 ouput shaft

2007 did not have the same gearbox as any other year. That was the year of the BaneBots 56mm gearbox, which in as-shipped-in-the-kit form was not remotely ready for the task of playing a very physical game like Rack 'N Roll. (Whether they were ready after the fixes that went out was a rather subjective matter that depended on your application.)

You are correct that the Toughbox first entered the kit in 2008. We used SuperShifters that year on 1618, so those sat off to the side.

02-08-2016 21:25

ratdude747

Re: pic: 716 ouput shaft

That's interesting. On 1747 as a freshman in 2008 I remember finding 4 old KOP gearboxes cases made of cast metal; their rookie year was 2006 and they at that point had never used stock gearboxes (AM Shifter Gen2's in 2006 and 2007). Thus it made sense for 2 to be 2006 and 2 to be 2007. I hadn't even heard of Banebots doing KOP gearboxes although given the era I could see them being awful (chipped gear city)... My guess is two of the castings must have been 2005 ones that were "gifted" by 461 when the team was founded.

Sorry for the misinformation.

03-08-2016 22:36

sanddrag

Re: pic: 716 ouput shaft

Nice to see you're still in it Andy. I remember a white paper you published before the 2004 season being a huge inspiration for me when I was a student on 696. It gave us the confidence to build our very own custom gearbox for the first time, and is probably what really got me even more into design and CNC machining. You're a real asset to the FIRST community. Thanks for sharing your stuff and keep up the great work!