Tank Drive

[Electronica1]

Brecoflex has some good options with different backing options. You want to use self tracking belt so flanges don't dig into the carpet. Here is a team that has used the belts successfully before.

Or you could just wait for Andymark to sell their belt and pulley separate.

[Charger]

wow, that product though. I think a game of climbing is incoming and it looks like teams need more and more pushing power. But one question in my mind? how much belts are useful in FRC? (instead of wheels)

[EricH]

Originally Posted by Charger

wow, that product though. I think a game of climbing is incoming and it looks like teams need more and more pushing power. But one question in my mind? how much belts are useful in FRC? (instead of wheels)

It has been a long time since a tank tread drive was actually useful. I want to say '06 or so, maybe as recently as '07.

Does a tread system have its advantages? Yes. They're good for dealing with obstacles and rough terrain, and good for lots of traction (in some circumstances). However, they tend to have a lot of disadvantages, the chief of which is that if something goes wrong, you lose half of your drivetrain. It's no fun spinning in circles...

Someone was discussing using a tread system last year to handle the scoring platforms in Recycle Rush. No fewer than two teams that had previously mastered treads (back when they were often useful) spoke up with "We could do them, but we DON'T."

[carpedav000]

Originally Posted by EricH

However, they tend to have a lot of disadvantages, the chief of which is that if something goes wrong, you lose half of your drivetrain. It's no fun spinning in circles...

This can be remedied.

[carpedav000]

Originally Posted by carpedav000

This can be remedied.

Maybe I should explain my thought process here. Couldnt you use traction wheels in place of pulleys so that in the case of the belt breaking, the traction wheels take the place of the belt?

[EricH]

Originally Posted by carpedav000

Maybe I should explain my thought process here. Couldnt you use traction wheels in place of pulleys so that in the case of the belt breaking, the traction wheels take the place of the belt?

In that case, pull a 706 and use 14 traction wheels and no treads.

The point is that for most tank track drives, ONE failure can cripple your drivetrain. Design that out if you can. Otherwise, I'd go with a 6WD or 8WD just about every time (game dependent of course).

[asid61]

To be fair, I've never had a wheel fail during a match (or ever, really) and the only time we had DT problems was 2014 when we tried and failed a WCD for the first time.
If AM is selling these tank treads, I wouldn't doubt their strength in a match or be afraid of one side coming off.

[Edxu]

Originally Posted by EricH

In that case, pull a 706 and use 14 traction wheels and no treads.

The point is that for most tank track drives, ONE failure can cripple your drivetrain. Design that out if you can. Otherwise, I'd go with a 6WD or 8WD just about every time (game dependent of course).

Still waiting on that 8WD water game-optimized drivetrain...
#strongholdshavemoats
#watergame2016

[Charger]

Originally Posted by EricH

It has been a long time since a tank tread drive was actually useful. I want to say '06 or so, maybe as recently as '07.

Does a tread system have its advantages? Yes. They're good for dealing with obstacles and rough terrain, and good for lots of traction (in some circumstances). However, they tend to have a lot of disadvantages, the chief of which is that if something goes wrong, you lose half of your drivetrain. It's no fun spinning in circles...

Someone was discussing using a tread system last year to handle the scoring platforms in Recycle Rush. No fewer than two teams that had previously mastered treads (back when they were often useful) spoke up with "We could do them, but we DON'T."

Well, I thought tread system limits your maneuverability a lot. I think a ball shifter or a super shifter with traction wheels, will do the job. There was an offseason event in Turkey this year, and theme was 2006 Aim High. I was a volunteer there as a robot inspector. In 2006's end game, there is a ramp with 30 degrees that you need to climb. The only teams I have seen climbing the ramp safely, was the teams who use traction wheels.

[EricH]

Originally Posted by Charger

Well, I thought tread system limits your maneuverability a lot.

It doesn't. Trust me, it doesn't. *activates time machine* Back in 2003, I saw firsthand how fast a team could get out of the field. This tank-tracked robot started pointing one way, on one side of the field. In automode, it started straight, executed a beautiful 180-degree arc to the right, went up a nice copper-mesh ramp, fairly steep, across the HDPE on the top, down the other side, hung a 90-degree left turn, and went between the base of the field border and the wire to keep robots in. It ended up under the stands before anybody could hit an E-stop. Talk about fast and maneuverable! I think it took out a tote stack on the way to the ramp, too.

In 2006's end game, there is a ramp with 30 degrees that you need to climb. The only teams I have seen climbing the ramp safely, was the teams who use traction wheels.

Played it. Just so you're aware, one of the world champions used tank tracks, and is seen in http://www.chiefdelphi.com/media/photos/27366 parked on top of an even steeper ramp (along with 1 robot from 2005; the ramp is part of the 2007 robot).

A well-executed set of tank tracks is a thing of beauty in form and function--but an un-necessary and/or poorly-executed set of tank tracks is bound to end badly eventually. My team doesn't talk about one of our robots... the one with 4 tank treads to help us get over a field obstacle...