Chief Delphi - pic: Track System

Chief Delphi (http://www.chiefdelphi.com/forums/index.php)

- Extra Discussion (http://www.chiefdelphi.com/forums/forumdisplay.php?f=68)

- - pic: Track System (http://www.chiefdelphi.com/forums/showthread.php?t=56678)

Re: pic: Track System

How much does each drive module cost?

Re: pic: Track System

Quote:

Originally Posted by ChrisMcK2186 (Post 617854)

My team is looking to find a decent drive system that will stay together and work well. Do you recomend this?

Chris

Highly. This year, the only issues in the system (when other teams had it, 114 is going to use it next year) came through user error. As well as this, a powerful tranny will be available with the tank treads.

Quote:

Originally Posted by sdcantrell56 (Post 618437)

How much does each drive module cost?

Not sure of the individual cost. If you're interested in going with these next year (they'll be adapted to fir the field, if climbing is needed, it'll be modified to fit with that) just get in contact with Sam Shawe. You can contatc OutBack Manufacturing at www.outbackmfg.com, look around there for their contact info.

Re: pic: Track System

I am not really that interested in treads, but if they are good at machining FIRST parts, I would like to get a quote to machine parts for our new drivetrain. I am really looking for a cost just as a comparison.

Re: pic: Track System

Quote:

Originally Posted by RTTComanche17 (Post 617746)

Beware of (ab)using these track systems. My team (1662) thought about using them but decided against it for a cople of reasons:

1. Track material falls off. Last year we saw 753 at the davis regional and they did very well, bt they (ab)used the eystem so much, tread/track material started to fall off in pieces. This also happened this year where a team on our alliance (dont remember number) left a three inch long by inch and a half wide piece of material on the field.

2. These belts break if (ab)used too much. Just ask 997. In their 6th qualifying match sat. morning at the championships, they were pushed from the side and a belt snapped, leaving one side of the robot disabled. they said it took an hour to change both belts.

3. Teams do not gear them low enough. This year and last year, we have been able to psh or at least stop any robot with tracks. last year we had very low gearing with 4 two inch wide by 8 inch diameter IFI wedgetom traction wheels. We pshed 753 arond no problem. They did have more traction than us, but they were geared so high that they pulled too many volts when they lugged thir cims down low, their robot wold essentially shut down to protect itself, enabling them to be moved across the entire field.
This year we had 6 two inch wide 6 inch diameter IFI wedgetop wheels with a lowered center wheel and a bit higher gearing for mare speed and manuverability. Of the three track systems we encontered this year, we pushed two and stood up the third (they couldnt move us, we couldnt move them).

We love traction wheels:D We havent benn moved in the last two years!!
A track system cold definately outpush us if you designed them right.
Instead of 5 fps and 15 fps(most teams end up locking them in low gear anyway), try 2 fps and 6-8 fps or 3 fps and 9 fps.

Just tying to provide a little insight, thats all.

1. Track material falls off Last year it happened yes....but not This year? To an OutbackTrack at least. Interesting. Outback fixed the problem with a thicker track and beveled edges this year.

2. These belts break if (ab)used too much Both Belts snapped. :( Only because the force of the robot going sideways and the tracks moving forward put a wedge between the lower layer of the track and the drive wheel, Snapping the belt instantly. This problem can be fixt by enclosing the plastic layer of the belt more, allowing it not to move. At all, side to side.

The simplicity of the track system 997 is using allowed them to change out 2 belts completely in less than 45 minutes. In the past I have seen this take up to 3 hours. for just one track : /

3. Teams do not gear them low enough I would have to agree with you that the Gear ratio for a track system needs to be refined. The amount of traction a system like Outbacks needs the implementation of a well designed 2-speed gearbox. @ 2fps that track system would push anybody. I have yet to see a well geared track system be pushed by a wheel driven drive train. With 2 fps for lower and 7 for high gear. Driver practice. Good game.

***

For the most part teams tend to avoid using a track system for a drive train because it is a real pain in the As(s) to make them right. It is not the same as throwing 6 wheels/sprockets onto some axles and slapping a chain down. But, through trial and error a well designed Tred/Track system (in my opinion) has proven to be the most efficient if you want reliable traction/power.

FierceRabbit.
Maxwell.

Re: pic: Track System

Well, I've been listening to the people who may actually consider buying transmissions once we swing into gear to sell them, and so I've designed another one (Did it in the last hour. I got bored and inspired, and have mad CAD skillage....). The new one has a low speed of 4 fps, and a high of 10. Drivers will most likely stay in high gear most of the time, and when they hit a pushing match, they will shift down to be able to torque.

Re: pic: Track System

Quote:

This was going to be one of my suggestions to Sam for next year, Just change the final gear ratio so that when we need to push, we can push anyone, and in high gear we don't flail around trying to drive something that is too fast, 4:1 and 10:1 sound perfect to me :)

Also, the cost for the entire thing is only $1,200. The belts alone are 300 apiece so 1/2 of what a team would pay would be for the belts alone. For the quality of and time put into this drive train it is well worth the $1,200

Re: pic: Track System

Quote:

Originally Posted by 114ManualLabor (Post 618459)

4fps still might be too high for pushing. 3 or 2 fps would ensure victory in a pushing match. 10 fps sounds about right. If the robot is not top heavy. 15 fps, like 254 had, would be sweet.

Re: pic: Track System

Quote:

Originally Posted by 114ManualLabor (Post 618436)

For these tracks, they turn just as good as a 6 wheel, and for a full drive system, only cost $1200.

I'd debate the first half of your statement, but the second half is a little more interesting.

$1200? Maybe you just didn't elaborate, but that's illegal. There's a maximum price per component of $400. In addition there is now a rule that says entire subassemblies cannot be purchased from a vendor.

Given that the above is true, even if you split the system into two sides, you're looking at $600 per component, and you still have a complete subassembly, which clearly doesn't work with the 2007 rules.

I was under the impression teams using the tracks were all sponsored by Outback Manufacturing, not paying for the tracks. Could someone clear that up?

Re: pic: Track System

The tracks cost $300 a piece (2x=$600), and the material is cost covered by the team ($600), while Sam does the machining for them. Since you are not purchasing a finished assembly, rather the costs associated with the manufacturing, they do not fall under the same rule.

Re: pic: Track System

$1200 seems a bit ridiculous for a drivetrain. Does that include transmissions, because I guess that would make it a little more comparable to a wheeled drivetrain.

Re: pic: Track System

Quote:

Originally Posted by Gabe (Post 618617)

You are purchasing a finished assembly--an entire drive system.

We're talking about two different rules. You're talking about manufacturing costs. I'm talking about the fact that you cannot buy a completed subassembly under the 2007 robot rules, which is exactly what these tracks are.

Re: pic: Track System

Quote:

Originally Posted by 114ManualLabor (Post 618436)

For these tracks, they turn just as good as a 6 wheel...

Is this statement based upon something, like math, or just a subjective observation?

Re: pic: Track System

Quote:

Originally Posted by Cory (Post 618652)

Actually these tracks are completely legal, we made sure of that. I don’t know about any other team, but for us, we did not purchase the track from outback. $1200 is the estimate for the cost of the material that made up the tracks, not how much we paid outback for the tracks. Outback, as our sponsor, then machined the track parts out of the material that we provided. They gave us the pieces that they machined, and then we assembled it together. We did not purchase anything from Outback. The AndyMark transmission were bought separately.

Re: pic: Track System

Quote:

we ordered the belts seperatly so nothing cost more then the cost limit and theirfore they were legal, also the 600 dollars that we paid outback was for materials and he sponsored us the cost of machining.

Re: pic: Track System

Quote:

Originally Posted by kramarczyk (Post 618658)

Is this statement based upon something, like math, or just a subjective observation?

Both. The center pulley is lowered about a tenth of an inch. I also watched these, got a chance to play with them, have the CAD, and have done massive research on them.