pic: Track System
 

Re: pic: Track System
 

Where did you get Inventor versions of the treads?

They were originally designed using solid works, and I haven't been able to do anything with the files.

I don’t know if you’ve thought about this, but I’ve heard that the Outback Treads are completely un-maneuverable in high gear. 997 locked their AM shifters in low gear for this reason. Their robot moved fast enough in low gear!

Re: pic: Track System
 

The tracks are undergoing design changes to allow them to turn better all around.

I got the Inventor files through a member of team 997. However, now that I'm learning Solidworks, I kinda want to get them in solidworks so I have real stuff to learn on. Wanna swap?

Re: pic: Track System
 

Nice to see this tread system becoming more popular. From what I hear, it's an awesome setup, designed to push! I think our team was planning on getting some for an off-season project, but we'll have to see how it turns out. I can see them becoming a very popular product for FIRST teams.

Re: pic: Track System
 

The tracks worked great, I hope that Sam makes your team do awesome!
(670, 997 and 753 fully (ab)used them)

Re: pic: Track System
 

they are going to have different gearboxes and hopefully some other modifications, and Sam from Outback makes them better and better, so hopefully soon with some coordination between teams they will be close to perfect ;)

As for a solid works File...
It's what Sam originally made them in, if you contact him he might be willing to hook you up.

Re: pic: Track System
 

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.

Re: pic: Track System
 

I would have to agree that the advantages of a track system just don't outweight there weight penalty as well as complexity, cost, and reliability. A well designed 6 or 8 wheel drivetrain with high traction wheels will perform almost as well in brute strength but be much easier to build, and theoretically less prone to failure. If you break a belt you're completely, however if you break a chain in a wheel based drivetrain you still have partial drive, assuming you have multiple chain runs. Thats just my 2 cents

Re: pic: Track System
 

Nah. The belts are fine. We made the mistake of trying to move away while being pushed side way. That's what killed the belts. If we just sit there and don't try to move, the belts won't get damaged at all. It didn't take an hour, more like half a hour. And that's because we had to get around our platforms.

Re: pic: Track System
 

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

Chris

Re: pic: Track System
 

I would think that not being able to move when being pushed without snapping a belt would be a serious problem. I know our drivers drive away from people if they are in a pushing match to not lose time. Also snapping those belts and having to replace them costs a pretty good amount of money.

Re: pic: Track System
 

actually it wasn't that bad, we can move while being pushed from the side with a normal team, but this was against a beefy drive train and the brecoflex belts have a steel whire running in them and rather then jump they snap... while some teams when being pushed from the side move sideways, we do not move at all. just something we have to deal with, next year this wont happen, we are improving the rollers :D

Re: pic: Track System
 

670 was being pushed around left and right though, at SVR, Davis, and ATL.

I've thought about tank tread -- and while it is cool looking and works well, our team went with 4-wheel tank-style drive and haven't lost a pushing match once (well, maybe once to 1662...)

Re: pic: Track System
 

All hail the tank track! The tank track is the coolest drive train set up out there. (just look at the M4 Sherman)

But, its not cost effective, and they can be a bit slow and hard to turn. Just look at some of the new Military APCs that use a wheel system rather than tracks.

Re: pic: Track System
 

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

Re: pic: Track System
 

How much does each drive module cost?

Re: pic: Track System
 

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.

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
 

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
 

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
 

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
 

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
 

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
 

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

Re: pic: Track System
 

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
 

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
 

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.

Re: pic: Track System
 

I think that the center roller should be set lower. The little difference it had pretty much didn't matter on carpet when 100 lbs of robot is pushing down on it.

Re: pic: Track System
 

These tracks are by no means completed sub-assemblies, consider I personally assembled each track together from pieces and then built the drive train with them.:cool:

Re: pic: Track System
 

A couple things... The cost issue is beaten back by the fact that the bill is for individual pieces or the system. Machine time is donated to Outback teams that choose to work with them. Also, it gives teams who don't posses the huge resources of larger, more powerful teams, a better chance at having a highly competitive drive system.

Re: pic: Track System
 

So you guys think that if AndyMark sold their transmissions unassembled and billed you for the parts individually that they could be selling them for more than $400? Not quite.

No matter how you try to justify it, $600 worth of parts that are meant to be assembled together is the same as a $600 part... I don't see where the argument is.

Re: pic: Track System
 

OK, so enlighten me, what metric(s) did you compare and how did you calculate it (them).
Where did you get the research data and what intermediate conclusions did it allow you to draw.

i.e. Treads are good because they distribute the load and allow the weight concentration to be more central compared to a 4x4 system which decreases the energy lost to scrubbing the wheels without reducing forward tractive force. - Drivetrain Basics White Paper - Chris Hibner - http://www.chiefdelphi.com/media/papers/1443

Note: I am not trying to hijack this thread with a discussion of what is the "proper" amount center wheel drop, so lets leave that discussion for another thread.

Re: pic: Track System
 

exactly how I see it.

If they were to be sold as is, I think they should be illegal.

Re: pic: Track System
 

A slight sidebar from the normal topic... But take a look at a large majority of the threads that people post showing new and thought provoking ideas. Have you ever noticed that every single one of these threads de-evolves into a "this isn't legal, that isn't legal" type argument, and less of the true point of FIRST: actual design and engineering inspiration and learning? As a student, I've become very turned off to sharing my designs on here anymore. Don't expect to see them anymore. Seriously, if every time I post something like this, a rule discussion is held, then I'm just gonna give it up, because that's not what I here for.

Sidebar over, continue your normal discussion on the issue.

Re: pic: Track System
 

It's also about working within the predetermined rules and constraints.

If this isn't intended for FIRST, the rules change next season, or the price is lowered, then it is an awesome piece of work. Otherwise, it's just not legal.

Don't get me wrong immediately jumping to the legality of it; I admire a lot of the work you post and use a lot of it for inspiration.

Re: pic: Track System
 

This has everything to do with the intent of selling them. When you invest or plan to invest that sort of money into (legally) selling these, then yes, I imagine you should listen to all of the comments being made regarding such things. Andy and Mark had some difficult hurdles that they had to jump over to make it in this business selling to FIRST teams... if you want to compete in that market, you HAVE GOT to address the same issues that they have... you can't create convinient loopholes and not expect a few (so far) harmless opinions to be voiced...

Re: pic: Track System
 

The real point of that small sidebar was that this has a tendency to happen on just about every new and different idea or image that gets posted here.

I already realize the legality issues, as does Sam Shawe from outback, and we are working on finding a way to make the tracks legal.

Re: pic: Track System
 

My team has used tank treads since probaly 2004 - 2006. We really liked them and they worked great. We could turn on a dime, and usually come out on top of a pushing battle. I am pretty sure we had a good way of doing it. But...there is always the problem of treads breaking during a match, worst yet a elimiation round match. We were able to change one tread in a half hour under pressure. Thankfully this year we did away with the tank treads and used 14 wheeler design which I think works betters then our old design of tank treads. Next year we may use the same drivetrain idea but make it lighter and cheaper.

Re: pic: Track System
 

I did a bit of thinking, and based on this idea, your robot is illegal, just like every other team out there. You pay for individual parts to be machined, WITH THE INTENT OF ASSEMBLING THEM together, correct? How is this any different? The only change is that an adult mentor (Sam from outback) is designing them, and letting multiple teams build them. The only cost if for the individual pieces and materials. So my point is simple that if these are illegal, as they come in pieces, and you have to work closely with outback, then so are every single robot that competed in Champs.

Re: pic: Track System
 

You don't seem to understand the issue here. We didn't pay a dime for any of our manufacturing. Hell, we did more than 50% of it ourselves. I didn't pick up the phone and make a call to my local robot parts distributor telling them to ship me one of their new drivetrains they have sitting on the shelves... (edited)

I am comparing outback manufacturing to andymark, where we will assume both companies will be making and selling robot parts to be used as FIRST legal components on their competition robots.

Never once did I say the teams who had them this year were using them illegally... I am just mentioning the possible issues that would arise IF AND WHEN you try and sell and distrubute them in a manner similar to AM, Banebots, etc. I brought this all up simply because I was under the impression that you would be selling these next year, as you noted the prices and the intent to make these available (at a cost) to all teams interested.

There is a HUGE difference there.

Re: pic: Track System
 

Ok, that's all I wanted to get it clear. That the tracks we used this year were legal because we did not just buy it off the shelf. As for Outback selling them next year, it’s none of my business.

Re: pic: Track System
 

So what you are saying is that Outback is manufacturing these for free and that there is $600 worth of material. Do you think that Outback would cut a discount on machining for other parts for FIRST?

Re: pic: Track System
 

Aluminum plates for the sides are really expensive. The belts that bought separately from a different company are like $300 a piece. The belts have steel wires running through them. 4 hard plastic rollers per tread; A few of the parts of each tread had to be made out of solid block of aluminum. The rounded triangular tubes that held the two plates together had to be made out of at least 3” by 3” by 3” of solid block and there are two of those per tread. The rear gear that drove the belt was made out of a massive block of aluminum. So yeah, lots of expensive materials.

For FIRST in general? I’m not sure. You would have to ask them. But I do know that Outback would be happy to sponsor individual teams.

Re: pic: Track System
 

What thickness and dimensions of sideplates did you use for th modules. I am asking all of these questions because I am trying to get a general Idea for how much it will cost to get the parts for our new 8 wheel drivetrain machined. Although if they are interested in sponsoring teams and donating machining then it only comes down to the material cost which I believe for our design is around $150 or $200 which is not too bad for a sweet drivetrain, but that is all dependent on their willingness to sponsor us.

Re: pic: Track System
 

I Don't think they have time for much else....What may cost $150-$200 in raw material costs would cost 15 grand in shop time. Brainstorming, CAD design/toolpaths, CNC a fixture, run the CNC, process the parts....ect.

I don't think most teams understand how much time and effort private businesses sacrifice to help with this program. Give Sam a call though. I'm sure he will give you his 2 cents on the matter....I may be totally wrong.

Re: pic: Track System
 

I understand what you are saying and acknowledge it, but we are not looking for design work or anything like that. I have a design completely done in CAD and just need someone to physically machine it, which cuts out a majority of the difficult work. Also I am really just wondering the cost for this and if they are willing that would eliminate the need for us to approach more machine shops to do our CNC work.

Re: pic: Track System
 

I will get back to you on the dimension after I go check it when I get home. Yes, I took a tread home to play with. :D

Re: pic: Track System
 

Each side plate is machined out of ¼ inch plate. The plate was at least 6 inches wide and about 30 inches long.