pic: Two bot side balance

[smistthegreat]

Originally Posted by Cory

This is clearly illegal. Physics does not support a scenario in which that robot can remain on the bridge without applying force to both sides of the angle, unless the CG remains over the bridge surface, which is highly improbable.

Cannot believe this was allowed to compete after 118 was denied.

It's not probable, but it is possible that their CoG is indeed over the bridge surface. Just from looking at this picture, it seems like they have a relatively small superstructure, which could free up weight to use as ballast towards the bridge side. However, I have no idea if this is actually the case. If someone from this team or someone who is familiar with this robot could clear this up, that would be wonderful.

EDIT: From this image, it appears that the side over the bridge is considerably more dense than the other side, including solid aluminum (steel?) blocks being used as ballast, so the possibility of an extremely biased CoG is possible. However, it also appears that there is a metal piece under the robot touching the side of the bridge. I can't tell if it's just used for allignment or if it reacts against the bridge.

[AdamHeard]

Originally Posted by smistthegreat

It's not probable, but it is possible that their CoG is indeed over the bridge surface. Just from looking at this picture, it seems like they have a relatively small superstructure, which could free up weight to use as ballast towards the bridge side. However, I have no idea if this is actually the case. If someone from this team or someone who is familiar with this robot could clear this up, that would be wonderful.

EDIT: From this image, it appears that the side over the bridge is considerably more dense than the other side, so the possibility of an extremely biased CoG is possible. However, it also appears that there is a metal piece under the robot touching the side of the bridge. I can't tell if it's just used for allignment or if it reacts against the bridge.

it still looks to be leaning to the right, if the inner edge of the monorail was removed the robot would fall (my guess). If this is the case, it's illegal.

[JABot67]

What I heard and observed from being at the competition is that 3534's center of gravity is indeed over the bridge when it does its side hang.

Originally Posted by Cory

This is clearly illegal. Physics does not support a scenario in which that robot can remain on the bridge without applying force to both sides of the angle, unless the CG remains over the bridge surface, which is highly improbable.

Cannot believe this was allowed to compete after 118 was denied.

You can clearly see from the picture that this team tried to put as much weight on one side of their robot as possible. Why would they have designed it to ALMOST have its CG above the bridge but not quite?

[jblay]

People need to relax a bit before coming to conclusions on this and ask questions.

Hey cptopher, can you explain how this works because it's legality might be questionable? If it is legal though that is some clever work and I commend you for pulling this off.

[PAR_WIG1350]

I'm glad that this worked for you; it is really cool. In 2010, My team, 1350, built a robot that functioned identically when completely inverted (it didn't have a top, just two bottoms joined at their bumper zones). It worked, but not particularly well, especially after the frame started to bend.

[Thad House]

Originally Posted by smistthegreat

It's not probable, but it is possible that their CoG is indeed over the bridge surface. Just from looking at this picture, it seems like they have a relatively small superstructure, which could free up weight to use as ballast towards the bridge side. However, I have no idea if this is actually the case. If someone from this team or someone who is familiar with this robot could clear this up, that would be wonderful.

EDIT: From this image, it appears that the side over the bridge is considerably more dense than the other side, so the possibility of an extremely biased CoG is possible. However, it also appears that there is a metal piece under the robot touching the side of the bridge. I can't tell if it's just used for allignment or if it reacts against the bridge.

Over on the left side of that picture you can see stacks of weight attached to the frame. In addition the battery is also located on that side.

[pfreivald]

If that's nothing more than a CG trick, that's just awesome.

[s_forbes]

Given that the robot was able to drive up the bridge (I'm assuming from the other photos that it made it up under it's own power), there must be enough weight over the drive wheels for it to power itself up, in which case grappling the lip is not necessary to stay on the bridge. I highly doubt you would be able to drive a robot up the bridge if it relies on clamping force on the lip to keep it from falling off. I'm curious as to how the friction from the portion of the robot touching the lip did not inhibit it from driving up though.

Doesn't look "clearly illegal" to me.

Congrats to 3534 for creating and carrying out this design! Out of the box approaches are risky but oh so cool.

[lnader]

I was able to see this robot in action. It is steel ballast on the edge. The parts you see under the robot are alignment guides, and do not touch the sides the the rail when it is on the bridge. I believe (not being certain) that there is a surface which rides on top of the rail.

It would be no different than if a robot got bumped off the side of the bridge and they were resting on their chassis.

The head referee checked at the end of each match to make sure there was no lateral contact on the bridge.

[Tom Bottiglieri]

Wow, cool! It's hard to tell from the photo that there is ballast on the bridge side of the robot, thanks for clearing that up.

Are you going to champs?