Bridge Manipulator

[Robogineer1649]

I have seen three types of bridge manipulators triangles like 846's robot, i have seen just straight metal pushing down on the bridge like 233's robot, and i have seen wheels like our robot 1649's robot. I was wondering what type of bridge actuator you used if I missed it and which bridge manipulator worked the best. I know that all three types were able to get the bridge down but I want to hear your pros and cons for each bridge.

I like the triangle manipulators because you don't have to push down on the bridge you can just lower the manipulator and drive up and over.

[Ekcrbe]

Sorry to ask, but aren't the "triangle" from 846 and the "straight" wedge from 233 just different implementations of the same thing? They are both passive manipulators, unless I have misunderstood the design of 233's system.

Either way, we had passive wedges with a triangular arm on each edge of the robot and a lexan strip between them. We also had locks on each arm so we could put all our weight behind the manipulators. Except for the rare time when the lock failed to engage correctly, we barely had to slow down to climb the bridge. We were very happy with their performance overall.

[ttldomination]

Our bridge manipulator was a passive-wedge style with a gate lock to hold it down.

I have to say, our robot was full of inconsistent components, but the bridge manipulator worked better than we could have hoped.

- Sunny G.

[Robogineer1649]

They are both passive bridge manipulators but they are different designs one was built directly just to push down on the bridge while the other one was built to push down the bridge as the robot approached it.

[sleepyizme]

My team had a "passive" manipulator that was essentially two thick sheet metal tusks put together, lowered by a single pneumatic piston (we changed it from the original picture). This let us drive straight into the bridge without stopping, saving us precious time, but we were also able to lower the piston when the Joebot was right in front of the bridge, so it could be used "actively."
You might notice that the top of the tusks is very close to the edge of the bridge. Every once in a while, we encountered an issue with the tusks driving under the bridge and pushing it up.

[Ekcrbe]

Originally Posted by Robogineer1649

... one was built directly just to push down on the bridge...

So this would make it active, not passive, right?

[Robogineer1649]

Correct

[slijin]

See this thread.

Originally Posted by slijin

118. Their entire frame was built for passive bridge manipulation - both pushing it down and lifting it up - and a good portion of their mechanisms were devoted to balance assists. They had a beautiful system to assist a double balance, complete with lights to indicate an unbalanced v balanced bridge. And that's all before their stinger.

[Chexposito]

http://youtu.be/g_7ljqbIdi8

[sebflippers]

I believe we (2914) had a really unique system. Just drive into the bridge to tip it the other way, or drive back then forwards and it will swing right to us.

[Walter Deitzler]

3397 had a "hammer" (actually it was a pvc arm with an elbow joint) on our robot that was powered by a Fisher-Price motor with the standard KoP gearbox. It worked beautifully.

[Chinmay]

Like someone mentioned, we were subtly different from the triangular wedge. Here is a short report that explains the design considerations

http://f.cl.ly/items/3l203Z2v272J1n3...her_Report.pdf

[CalTran]

Originally Posted by sebflippers

I believe we (2914) had a really unique system. Just drive into the bridge to tip it the other way, or drive back then forwards and it will swing right to us.

Is the manipulator we're looking at supposed to be the "roll cage" like polycarb or the piece of aluminum somewhat under your shooter?

[MIT_MAN]

Our wheelies were incredibly consistent with lowering the bridge... even in autonomous

[DominickC]

We used our cannon to get the bridge down. Worked every time!