Bridge problems?

[archiver]

Posted by Elliot Johnson at 04/09/2001 11:25 PM EST


Student on team #218, HP Robotics Team, from Highland Park High School and Double-E Inc..



I had a great time at Nationals this year. As a senior in High School, I hope I can continue to participate through college. I've been on my school's team since freshmen year, both my first year in high school and my team's first year in FIRST. This program is, without a doubt, the most unique, inspirational, and exciting things offered to students. I hope all the teachers, parents, engineers, and voluntieers know how thankful every FIRST student is for what they do, and know how much this program affects the students' lives.

And a quick question about that bridge. My team couldn't make it to a regional so this was our first time to play on the competition field. We built a practive bridge that we practiced on quite a bit without trouble. However, at the Nationals competition, we kept running into a big problem (this was on the galileo field). When robots would go over the bridge, the force from the bridge falling would cause it to bounce up. The angle iron on the raised sidef would land on top of the wood beam rather than on the side so the whole bridge was resting on the angle instead of directly on the beam. This made the bridge incredibly hard to work with and nearly impossible to balance. Did this happen often at the regionals or on other fields at Nationals? and how did teams work around this or prevent it from happening?

-elliot

[archiver]

Posted by Chris Hardman at 04/09/2001 11:42 PM EST


Student on team #111, WILDSTANG, from Rolling Meadows and Wheeling High schools and motorola.


In Reply to: Bridge problems?
Posted by Elliot Johnson on 04/09/2001 11:25 PM EST:



We didn't have so much of a problem with the bridge coming off it's fulcrum. The problem we had was that with all of the use on one bridge they tend to be more loose. In one of the finals matches a ref pulled the goal off the bridge and when the goal was off, the bridge automatically balanced itself. Kind of interesting if you ask me. We also would position the goals perfectly but for somereason with the bridge wanting to go one way, it caused an error in balancing. we managed to over come it and continue. We did not the bridge off it's fulcrum in one of the finals matches at Motorola Midwest Regional. These problems are what i noticed on the acrhimedes field.

chris
: And a quick question about that bridge. My team couldn't make it to a regional so this was our first time to play on the competition field. We built a practive bridge that we practiced on quite a bit without trouble. However, at the Nationals competition, we kept running into a big problem (this was on the galileo field). When robots would go over the bridge, the force from the bridge falling would cause it to bounce up. The angle iron on the raised sidef would land on top of the wood beam rather than on the side so the whole bridge was resting on the angle instead of directly on the beam. This made the bridge incredibly hard to work with and nearly impossible to balance. Did this happen often at the regionals or on other fields at Nationals? and how did teams work around this or prevent it from happening?

: -elliot

[archiver]

Posted by Kris Verdeyen at 04/10/2001 1:52 PM EST


Engineer on team #118, Robonauts, from CCISD and NASA - Johnson Space Center and Friends.


In Reply to: Bridge problems!!!
Posted by Chris Hardman on 04/09/2001 11:42 PM EST:



At the Lone Star Regional , the bridge became unseated after a particulary vicious crossing, and we were unable to balance, even with another team pulling down on it from the other side. After the match, the accouncer came on the PA and accnounced that "the bridge was designed to do that". It had also happened to a few other teams. The workaround was simply to go over it more slowly.

[archiver]

Posted by Alan Federman at 04/10/2001 1:54 PM EST


Engineer on team #255, Odyssey, from Foothill HS, San Jose and NASA.


In Reply to: Bridge problems!!!
Posted by Chris Hardman on 04/09/2001 11:42 PM EST:



: We didn't have so much of a problem with the bridge coming off it's fulcrum. The problem we had was that with all of the use on one bridge they tend to be more loose. In one of the finals matches a ref pulled the goal off the bridge and when the goal was off, the bridge automatically balanced itself. Kind of interesting if you ask me. We also would position the goals perfectly but for somereason with the bridge wanting to go one way, it caused an error in balancing. we managed to over come it and continue. We did not the bridge off it's fulcrum in one of the finals matches at Motorola Midwest Regional. These problems are what i noticed on the acrhimedes field.

I heard other teams (66) complaining on how easily the Galileo bridge came off its pivot - they said it happened to them 2 or 3 times on that field. I saw it happen once when we were playing and it really hurt us (255) but please note the average scores on Gallileo were much higher than the other divisions - so maybe it was also easier to balance? The highest score we had was on Einstein - so who knows if it matters. And about
being ranked 9th and not getting selected - there were lots of teams that should of been in the finals that weren't. Just the nature of the game.

[archiver]

Posted by Jason Iannuzzi at 04/10/2001 7:44 AM EST


Engineer on team #11, Marauders, from Mt. Olive HS. and BASF, Rame Hart, CCM.


In Reply to: Bridge problems?
Posted by Elliot Johnson on 04/09/2001 11:25 PM EST:



We were on Galileo field also, and I can say that was the first time we had seen that happen. We attended two regionals (Langley and Mid-Atlantic) and not once did we see the bridge come off its pivot.

Particularly distressing was the fact that it happened to us in two separate matches on Galileo. We scored 62 and 28 in those matches. Our average without those two matches was 332, our average with those two scores, lowest dropped, was 293.4. We missed an eighth place seed by 0.5 points. We weren't picked by any alliance. It's very disheartening to know you missed the playoffs because of problem with the playing field.

[archiver]

Posted by Wayne Doenges at 04/10/2001 9:57 AM EST


Engineer on team #535, G-Force, from Huntington North High School and UT Electronic Controls.


In Reply to: Bridge problems?
Posted by Elliot Johnson on 04/09/2001 11:25 PM EST:



We had the same problem with the Newton field. Our first match we had two robots go over the bridge and unseat the bridge. When we tried to pull the bridge down, we actually lifted our robot off the ground and there was no way for our robot to balance the bridge.
We also had a bridge problem at the Western Michigan Regionals. The bridge was constantly coming off it's fulcrum.

[archiver]

Posted by ChrisH at 04/10/2001 11:28 AM EST


Engineer on team #330, Beach 'Bots, from Hope Chapel Academy and NASA JPL, J & F Machine, Raytheon, et al.


In Reply to: Bridge problems?
Posted by Elliot Johnson on 04/09/2001 11:25 PM EST:



The bridge we used at LA and San Jose (it was the same one) was "sticky". It was hard to move and was not truly tristable. It would often balance with the edge 2 or three inches off the floor. I think FIRST reworked the bridges after the regionals to loosen them up. Maybe they went too far?

Chris Husmann,PE
Team 330 the Beach'Bots

[archiver]

Posted by Tom S. at 04/10/2001 4:14 PM EST


Student on team #177, The Bobcats, from South Windsor High School and International Fuel Cells.


In Reply to: Bridge problems?
Posted by Elliot Johnson on 04/09/2001 11:25 PM EST:



I did not notice much of a difference between the bridges on galileo and einstein... i can't say anything about the other fields since i didn't drive on them...

in only one of our matches on galileo did it come off the pivot, and if my memory serves me correct, we were still able to balance both goals from off the ramp.

Just thought i'd throw my opinion out.

Tom Schindler
Driver from Team #177



: I had a great time at Nationals this year. As a senior in High School, I hope I can continue to participate through college. I've been on my school's team since freshmen year, both my first year in high school and my team's first year in FIRST. This program is, without a doubt, the most unique, inspirational, and exciting things offered to students. I hope all the teachers, parents, engineers, and voluntieers know how thankful every FIRST student is for what they do, and know how much this program affects the students' lives.

: And a quick question about that bridge. My team couldn't make it to a regional so this was our first time to play on the competition field. We built a practive bridge that we practiced on quite a bit without trouble. However, at the Nationals competition, we kept running into a big problem (this was on the galileo field). When robots would go over the bridge, the force from the bridge falling would cause it to bounce up. The angle iron on the raised sidef would land on top of the wood beam rather than on the side so the whole bridge was resting on the angle instead of directly on the beam. This made the bridge incredibly hard to work with and nearly impossible to balance. Did this happen often at the regionals or on other fields at Nationals? and how did teams work around this or prevent it from happening?

: -elliot

[archiver]

Posted by Kieran at 04/10/2001 8:20 PM EST


Student on team #11, M.O.R.T., from Mount Olive High School and BASF.


In Reply to: Bridge problems?
Posted by Elliot Johnson on 04/09/2001 11:25 PM EST:



I think the bridge falling off it's fulcrum was in it's design. Because if it has happened on more then 1 field and in multiply competions there is either a flaw in it's plans or it was built incorrectly in about 20 competions. The chances of this happening about about 15%. Anyway i think that they should of used the old rule "measure twice cut once".

-Kieran