A New Monster is Born

[Chris Hibner]

The 2002 Walled Lake Monster is finally finished. The attached picture generally sums up our robot. I uploaded more pictures to the gallery so you can see them as soon as they are accepted. Also, more pictures will be on our website tomorrow (www.monsters308.com).

As you can see, the general strategy is to get two goals and lift them for traction. We can actually hold all three goals at one time, but we only lift two (the third is not necessary).

Our goal grabbers are nearly automatic. We can be off by nearly 10 inches to either side of the center line between the two goals and still have good automatic engagement.

We have another nice feature when we grab the goals. If you look at the picture, the goals are farther apart than 32 inches. When we get the goals, the natural motion of the robot and goals forces each goal outward away from the robot by about 5 inches on each side. Therefore, if you don't beat us to the goals, the 32 inch gap between the goals will be about 27 inches by the time you get there. We can actually make the gap smaller than that when we drive it a certain way. We felt it would be hard to squeeze a robot into gap smaller than 28 inches .

Anyway, I hope you enjoy the pictures. Hope to see everyone at one of the competitions.

-Chris

[Chris Hibner]

I forgot to attach the file. Try this.

[Quain]

well, just a thought, but what happens if you <i>don't</i> get to the goals first? If you only get one goal and lift it, you have no counterweight to counterbalance...? Its look very cool though...

[Chris Hibner]

Originally posted by Quain
well, just a thought, but what happens if you <i>don't</i> get to the goals first? If you only get one goal and lift it, you have no counterweight to counterbalance...? Its look very cool though...

That is an excellent question. It is actually a question that I have the answer for, but I'll hold off on answering it for a little while. I'm hoping we get more questions like this one and I can anwer them all in one post (instead of posting a lot of times). If your question ends up being the only one, I'll answer it either tomorrow or the next day.

[Jnadke]

The question of the century is...

...how much of a beating can those arms take? If you're not willing to give the goal up. The team's just gonna take your 'arm' along for the ride.

[Andy Baker]

Chris,

Yet another masterpiece to come out of Walled Lake. This is sure impressive! Two goals totally off the ground... yikes.

I have a question:

It appears that your treads are shiny... are they metal or rubber?

Take care,
Andy B.

[Chris Hibner]

There has been a few good questions about our robot. Here are some answers.

Originally posted by Quain
well, just a thought, but what happens if you don't get to the goals first? If you only get one goal and lift it, you have no counterweight to counterbalance...? Its look very cool though...

You are correct that if you don't have two goals, they can't be lifted due to having no counterbalance. However, there are two answers to your question:

1) We have a third arm that wasn't yet mounted when the picture was taken. It is a spring loaded latch mechanism that is off the front of the robot. We can grab one goal using that and drag it around really well.

2) We don't really need to get to the goals first. As long as some team doesn't get there and move them apart by 10 inches before we get there, we'll still latch the goal. We think it will take a team about 1 to 2 seconds to move the goal that far apart once they get to the goals, so we think we have about a 2 second cushion to lose the race. Since we get there in a very short time, it is very unlikely that this will be a problem.

Now, once we get the goals, we lift fully off the ground quite high (we're not releasing the numbers on this yet). If the other team that gets to the goals doesn't lift, we'll have the traction and should be able to win the tug-of-war. If the other team is a lifter, they better be able to lift pretty high or we will once again get the traction and should be able to win the tug-of-war. The outsides of the goals in the picture are drooping a bit since we didn't adjust the top link yet. They are completely level when the link is adjusted.

Originally posted by Jnadke
The question of the century is...

...how much of a beating can those arms take? If you're not willing to give the goal up. The team's just gonna take your 'arm' along for the ride.

Our design philosophy was that our robot should be like a jet fighter landing on an aircraft carrier. We designed the arms such that we can go toward the goals at top speed and as long as we're within about 10 inches of the center-line between the two goals, we'll snag them.

The arms are designed to hit the goals while the robot is travelling at about 14 ft/sec. Unfortunately we had to temporarily remove our transmissions to save weight, but we still go pretty fast and we've tested hitting the goals at full speed with no problems.

In order to go crashing into the goals at top speed, we had to make them very strong. In light of this, I don't believe a tug-of-war with another robot will be a problem. In fact, since we lift pretty high and will have about 500 lb of downforce to push with, we hope it will be the other robot going along for the ride.

Originally posted by Andy Baker
I have a question:

It appears that your treads are shiny... are they metal or rubber?

Take care,
Andy B.

First, thanks for the nice words.

The treads are Kevlar reinforced urethane timing belts with aluminum cleats. I can't remember which team we got the idea from for the cleats. Would you know what team that is, Andy?

The treads work VERY well. Tons of traction, it turns REALLY fast, and we've never thrown a belt - even while we're moving with the goals lifted. We have a fancy tensioning device the should keep the treads on without much issue.


Lastly, new pictures of our robot showing a little more detail should be up on our website by noon today.

-Chris

[Todd Derbyshire]

Quick question are you running on drill motors because if your not don't expect to get two goals

[Chris Hibner]

Originally posted by Todd Derbyshire
Quick question are you running on drill motors because if your not don't expect to get two goals

We have a custom gearbox to couple the Chiaphua motors and the drill motors together. (Our drivetrain uses 4 motors total.) Without our transmission we get to the goals in 3 seconds from power on. With our transmission it's about 2 seconds.

-Chris

[dense]

the robot is nice but...

i read in the rules that you cannot upend the goals in anyway...

am i right or wrong?

We're a maneuverable, ball manipulating, goal moving, xyz robot, are we the only ball manipulators? Hope to have some pics soon

[Chris Hibner]

I forgot to post a picture of our transmission that we made. I mentioned in a previous post that we had to take off our transmissions to make weight. We almost saved enough weight to add them back in and we hope that with a little work in the pits that we can put them back on. Enjoy the picture.

Also - in response to the above post: you can pick up the goals completely off the ground, you're just not allowed to tip them on their sides.

-Chris

[Matt Reiland]

Looks like a CVT with the seat motors moving some type of interface between the cones?

[Ian W.]

Wow, you're transmission looks quite like ours. We used two drill and two chipuah motors also. we also have a secret weapon, which let us push a 150lbs or so man down a tile floor, yet we still go at a relatively fast clip. ask micheal for the specs on that, cause i'm just a programmer.

[Katie Reynolds]

Our robot cannot be stopped by a goal and a 350 lb man pushing against it!

- Katie

[Don Taylor]

Your transmission looks like a work of art (or should I say a work of engineering). Great job! We look forward to meeting you at some of the competitions.Great looking bot !
Make sure that you surf by Metalinmotion.com and check out ours. We have many pictures and videos for your viewing pleasure, and also take a shot at our 'question of the day' and win a prize at the nationals.

Don Taylor
M-N-M Team 343