Robots Tipping Over

[EricH]

Originally Posted by Nawaid Ladak

for those of us who remember, Tipping five years ago was almost an every match occurance. I honestly miss robots tipping over, those were the days...

I don't really. A high C.G. cost my team a shot at the finals. Having a little interaction involving another robot and the step didn't help...

Yeah, we had a high CG and a wheelie bar, and still went over at least 4-5 times. One was a fall off the bar. One was a run-in with the border. Two were caused by robot interaction (and one of those, we were about to get up, but the robot came back, tipped us onto our side, and shoved us into a ball corral).

The fun part was the next year. We had wedges on our sides and a flat traction-reducing plate on the back. The one time we tipped was high entanglement, and we went over backwards. The fall freed us, and the next thing you know, we're stacking away.

Yet it's a bit more exciting when a robot is about to go down and doesn't, or goes down and gets back up...

And back on topic, I don't remember a single robot tipping this year.

[Al Skierkiewicz]

I saw a few teams teeter on Saturday. One got hung up on another robot but was stopped by the driver's station. Eventually the two robots were able to separate. Another robot jumped and got fully up on a trailer. Luckily both sides of the front were hung and the robot didn't go over. Unfortunately, all the wheels were off the ground the and the robot didn't move the rest of the match.

[Andrew Schreiber]

Originally Posted by EricH

Yet it's a bit more exciting when a robot is about to go down and doesn't, or goes down and gets back up...

And back on topic, I don't remember a single robot tipping this year.

Agreed, I remember in 2005 2 cases where tipping was an interesting occurrence for us. First was when we got knocked over and actually bounced off our arm and came right back up (it was designed to be able to right us should we tip) The other was when 33 brought their arm down on top of a tetra we were holding by accident (they were on our alliance) Instead of losing the tetra 33 was pulled sideways and onto the ground. It showed how good a grip we had on the tetra.

And no, I saw a lot of hard hits but no tipping. As opposed to last year, I saw lots of robots on 2 wheels going around corners and several on no wheels after a failed hurdle.

One last thing, plenty of robots put funny stickers on the bottom explaining that if you can see this something bad happened. On a related note, in 2004 RUSH had a sticker about if you can read this we are hanging.

[Dan Petrovic]

166 is proud to say that they haven't tipped since week 1 in 2006. After the regional, we made modifications to lower our center of gravity and havn't tipped since.

Our 2007 and 2008 robots featured mecanum wheels and an extremely heavy drive chassis (70-80 pounds) so neither of those ever tipped.

A total of seven official competitions and even more off-season events without tipping.

I made a point somewhere here about how teams shouldn't put so much effort into making a light chassis. Put more effort into making your manipulator light.

[MrForbes]

Originally Posted by InfernoX14

I made a point somewhere here about how teams shouldn't put so much effort into making a light chassis. Put more effort into making your manipulator light.

I make that point over and over again.

[nahstobor]

Originally Posted by AdamHeard

Wait, so you were trying to tip someone?

With the bumper rules this year, the trailer strapped to your back and the inability to extend out the bumper zone it's impossible to tip a robot this year. But I guess someone had to try to get a yellow card, has anyone seen a yellow card or red card this year either, I forgot those existed.

Rookie teams next year will have some adjusting to do when they get back on carpet, no more full speed rams and full match pins or will there??

[dlavery]

Originally Posted by nahstobor

Rookie teams next year will have some adjusting to do when they get back on carpet, no more full speed rams and full match pins or will there??

We are going back on carpet?





.

[Herodotus]

Please no one get Dave started. We don't want him hinting about non-hint hints all summer.

[nahstobor]

Originally Posted by dlavery

We are going back on carpet?





.

That's no problem, I like the regolith.

[MrForbes]

dave was probably thinking "jello" not regolith

[XaulZan11]

Originally Posted by nahstobor

That's no problem, I like the regolith.

We are going back to regolith?

[nahstobor]

Well technically we were on carpet, except someone accidentally put their old shower wall on top of it after renovation.

[Nawaid Ladak]

I think C.G.'s Importan to learn about when building a robot, some of the newer teams might not comprehend or understand the subject matter, unfortunitly, the way the games are played these days, some of these teams will never learn. (some of these teams don't have engineering mentors...)

In 2004. Team 1402 had a robot that was stright up to the line, 5 feet tall, we learned very quickly about C.G. at our preship event. we had five practice matches, we tipped over 3 times in those five matches. We stopped, did our research and redid our frame down to 3 feet tall. a total redesizn later, we had a rookie robot that did not tip, but DID the tipping. (we learned too late that King of the Hill was the stratedgy for the game in 2004.)

our 2005 Robot was built using creativity, but the FIRST question we asked was how we could keep the C.G. low enough where we would be able to cap 4 tetra's at a time without tipping over... (we had to take into consideration the weight of four tetra's).

Because of our team's error in 2004 with our origional design, we never tipped over for the next two years

2006 and Bumpers were totally differen stories...

It's not the fact that i like to see robots tip over, it's just the fact that because robots tip over, either teams adopt to the issue, or learn something the hard way. and improve upon it.

[Cory]

Originally Posted by squirrel

I make that point over and over again.

I never understand this school of thought. It's somehow a good thing to make a drive base unnecessarily heavy, to the point where one only has 30-40 lbs for a scoring mechanism?

If you can optimize the weight of your drive base, you should. This does not mean you should have a 50 lb base and the remaining 70 lbs 4' off the floor...that's just not smart engineering. What it does mean is that when your scoring mechanism weighs 60 lbs you aren't thinking "Oh ****, how many 1" holes through 0.125" aluminum does it take to remove 20 lbs of weight?", because your robot is 10 lbs underweight. Or it allows you to add more functionality.

2007 is a prime example. How many teams made robots that had top tier scoring capability as well as double 12" ramps? If you made your base as light as possible, you could do both, and do them well. If your base weighed 2/3 of the allotted total, you'd be lucky to do either well.

In short, it seems like poor engineering to me to say that instead of more carefully controlling center of mass due to proper design, we'll just throw 2/3 of the weight onto the base to make sure we don't tip over.

[MrForbes]

Of course we don't design the base to be unnecessarily heavy, but we don't go to extra trouble to make it light...we don't bother with making fancy cutouts, or using aluminum shafts and gears in transmissions, or even using #25 chain. We do design the drive base so it is rugged and as light as it can be while requiring as little work and special stuff as possible, and easy to build quickly, so we can get the robot moving asap.

We do go to extra effort to make the stuff "up top" light, usually by designing a mechanism that has most of the weight down low.

I've never understood putting all that effort into making the drive base as light as possible, when the effort would be more effective if applied to the mechanism. If that means rethinking the mechanism design to make it simpler but still effective, all the better.

In 2007 we had a pretty heavy chassis, with an arm that was capable of hanging 6 rings, and ramp for a single robot. Being only our second year, we didn't do it all quite right, but the robot was pretty much untippable.