Re: pic: Team 148 - Robowranglers 2010 - Armadillo
 

Since Armadillo's twin Mia is competing this weekend and word will probably be out soon anyways, I thought I'd take a minute to discuss a somewhat "controversial" change we made to the robot...

Here is the rough timeline:
Our video was shot on the Saturday before ship, the video itself was edited during the day Sunday and released that Sunday evening... On Monday evening the Robowranglers held an open-house for the Greenville community, then put the robot in the crate late that night (early the next morning).

After the video shoot on Saturday night we (in typical "continuous improvement" fashion) began to discuss what we needed to improve.

We were concerned about the durability of the drivetrain, but didn't have any weight to spare to reinforce it. We were also disappointed at the way the robot traversed the bumps and felt lowering the CG would greatly improve the robots performance.

Early on in our game analysis (day of kickoff) we were trying to do cost-benefit analysis to determine how much those 2-points for hanging would really be worth. At the time we couldn't really tell, because we had no idea how hard it would be to score and had no "easy" way to simulate it. Playing with the actual robot gave us more of an idea of how many balls a match a robot could score.

At the start of our meeting Sunday, we made the decision to remove the hanging mechanism. We would use that weight to reinforce the drivetrain, and lower the CG. By the time the video was posted on Sunday night, the new "baller" Armadillo was up and running. She goes over the bumps smooth as silk forward and backwards, and the drivetrain has been significantly reinforced.

I know some people will question our decision to give up the hanging. I see it as a "no-brainer". When the decision was made, it was like a weight was lifted from my shoulders.

The Thunderchickens went through a similar analysis and made the same decision. Neither robot will be hanging for 2 points this year.

So thank you for all the compliments on our hanging, but you won't ever see Armadillo or Mia do that in competition. Instead you'll see a new-and-improved version of the drivetrain, on a lean, mean, soccer-ball scoring machine.

-John

Re: pic: Team 148 - Robowranglers 2010 - Armadillo
 

Our hanger is also the first thing to go when we add our new kicker for Boston.

I was wondering though, could you please still bring the arm with you to Atlanta? I'd love to get a nice look at it.

Re: pic: Team 148 - Robowranglers 2010 - Armadillo
 

We put it in the crate, it'll be there.

Re: pic: Team 148 - Robowranglers 2010 - Armadillo
 

Sweet, thanks :D

Re: pic: Team 148 - Robowranglers 2010 - Armadillo
 

Thats too bad, I really liked your arm.

And thats leads me to a question I have, how much does your drivetrain weight?

Robot looks great by the way, maybe we'll be in same division :)

Re: pic: Team 148 - Robowranglers 2010 - Armadillo
 

If you're not using your arm, can I borrow it? :)

Kudos to 148217 for making a gutsy move that will apparently pay off for them. :D

Re: pic: Team 148 - Robowranglers 2010 - Armadillo
 

That is a very interesting trade-off. I like it...I may not agree with the tradeoff, but this is a perfect example of how tradeoffs need to be made, and how design is an iterative process. Every team makes different trade-offs. I really appreciate you posting this and letting us know, it's cool to see how other team's make design decisions.

On the other side, my team's decsion regarding this topic was quite the antithesis. We figured teams wouldn't be switching zones with much frequency, and it would be worth putting more weight into our lift and kicker and just take an extra second or so to get over the bump. This is the great thing about FIRST: seeing how other team's decsions differed from your own, and seeing how the trade-offs made early on (and later on) affect performance, then learning from the decisons made.

I hope this works for you, I can't wait to see it in action! 148 and 217 are the quintessential examples of teams to look up to and strive to emulate, thanks for the inspiration you have provided to us all!

Re: pic: Team 148 - Robowranglers 2010 - Armadillo
 

We made that exact same decision in the final week of build. I have to say that I feel much better knowing that other teams felt the same way about hanging, particularly 148 and 217.

It was a difficult decision for us to make and we thought long and hard about the trade-off. In the end mentors and students came to a decision that this was the best move for us to make. Strengthen our drive train, lower the CG, and develop a new way to play this game.

Re: pic: Team 148 - Robowranglers 2010 - Armadillo
 

I guess I don't feel their feelings about hanging are at all universal. That's not what I took away from the post, at least. Not "all robots would be sufficiently better with hanging resources moved elsewhere", but "the 148 and 217 robots work >=2 points better without a hanger" (and evidently 399 is the same).

Then again, I could be rationalizing due to the costs sunk into my own team's hanger...

Re: pic: Team 148 - Robowranglers 2010 - Armadillo
 

Don't get me wrong, I am definitely not discrediting other teams' decision to hang. As a team we felt that we wanted to focus on making our other systems stronger and as a result we scrapped our hanging ability. As was mentioned, it was a trade-off that we felt we had to make, in part to lower our CG.

Re: pic: Team 148 - Robowranglers 2010 - Armadillo
 

John,

We ended up making the same decision, we felt that weight should be put elsewhere. So we improved our roller considerably and our kicker.

Can't wait to see MIA and Armadillo in action.

-RC

Re: pic: Team 148 - Robowranglers 2010 - Armadillo
 

good luck, i wish we could get our parts shopped so beautifully at GM. Sadly though, we are not sponsored by them. Great Robot! I am scared to face the Armadillo.