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Q3W science people: I have a project and I need some ideas.

Posted: Wed Nov 02, 2005 3:12 am
by Guest
In my Physics for Engineers class for the rest of the semester we have a project. The goal of this project is to build a bridge from wooden popsicle sticks, using a predefined glue. Every team will use the same popsicle sticks and the same glue.

The specifications for the bridge are the following:

-max weight: 300g (1 popsicle stick is about 1g)
-min length: 50cm (this will be the length of the gap)
-min width: 10cm (it must have a solid floor so a toy car can pass across it)

Only glue and popsicle sticks can be used to build the bridge. A 5cm hole must be made somewhere in the floor of the bridge for a plug to be fitted, which will pull it down to test its maximum supported weight.

The rating of the bridge will be determined by an R value. The R value is the following: R = (maximum weight suported) / (weight of the bridge)²

Therefore what I was thinking is to build a bridge that is maybe not very strong, but is as light as possible.

By the way, these are the design ideas I've had so far:

Image

Image

Image

I am not sure if we're allowed to make a bridge that does not have a straight floor though. The arcs are to be made as close to being a parabola as possible.

Any ideas?

Posted: Wed Nov 02, 2005 3:18 am
by andyman
I remember doing this...in fifth grade lol

Posted: Wed Nov 02, 2005 3:20 am
by duffman91
andyman wrote:I remember doing this...in fifth grade lol
Yeah seriously. Anyways, why re-invent the wheel? Look at some famous bridge designs and modify them. They are always the ones that win in these projects.

Posted: Wed Nov 02, 2005 3:23 am
by duffman91
My bridge, which always won most weight supported/weight of bridge squared

Image

Posted: Wed Nov 02, 2005 3:25 am
by Guest
That design is interesting, but we are not allowed to make it lower than the level of the table, therefore we will have to build extra towers to elevate it and that's going to increase its weight...

Btw it has to look pretty.

Posted: Wed Nov 02, 2005 3:26 am
by duffman91
ToxicBug wrote:That design is interesting, but we are not allowed to make it lower than the level of the table, therefore we will have to build extra towers to elevate it and that's going to increase its weight...

Btw it has to look pretty.
ok... so flip it upside down and lay it on the table. Seriously, these projects are supposed to test your inovation. Unfortunatelly, bridge building doesn't get any better than what it already is. Simple, effective design always wins.

Posted: Wed Nov 02, 2005 3:27 am
by Guest
duffman91 wrote:
ToxicBug wrote:That design is interesting, but we are not allowed to make it lower than the level of the table, therefore we will have to build extra towers to elevate it and that's going to increase its weight...

Btw it has to look pretty.
ok... so flip it upside down and lay it on the table.
Would the structure be as strong though?

Posted: Wed Nov 02, 2005 3:29 am
by duffman91
In my case(I had to flip it over myself), it was stronger.

Image

Posted: Wed Nov 02, 2005 3:30 am
by Guest
lol this reminds me of iSketch :olo:

Posted: Wed Nov 02, 2005 3:31 am
by mjrpes
I see that bridge spans the white river.

Posted: Wed Nov 02, 2005 3:52 am
by Guest
You are getting ON TO something out of your 3rd scketch.
When is your exam final due date?
If I can have a few days left...I am already working on it.

Posted: Wed Nov 02, 2005 3:53 am
by mjrpes
You are a very nice person, pete.

Re: Q3W science people: I have a project and I need some ide

Posted: Wed Nov 02, 2005 4:04 am
by Guest
[quote="ToxicBug"]In my Physics for Engineers class for the rest of the semester we have a project. The goal of this project is to build a bridge from wooden popsicle sticks, using a predefined glue. Every team will use the same popsicle sticks and the same glue.

The specifications for the bridge are the following:

-max weight: 300g (1 popsicle stick is about 1g)
-min length: 50cm (this will be the length of the gap)
-min width: 10cm (it must have a solid floor so a toy car can pass across it)

Only glue and popsicle sticks can be used to build the bridge. A 5cm hole must be made somewhere in the floor of the bridge for a plug to be fitted, which will pull it down to test its maximum supported weight.

The rating of the bridge will be determined by an R value. The R value is the following: R = (maximum weight suported) / (weight of the bridge)²

Therefore what I was thinking is to build a bridge that is maybe not very strong, but is as light as possible.

Can you show me the copy of the project so I don't fall behind.
PS:, Not being very strong won't get you anywhere.
You wouldn't want to cross that bridge that you build youself, would you?

Posted: Wed Nov 02, 2005 4:11 am
by DevastatioN

Posted: Wed Nov 02, 2005 4:13 am
by duffman91
DevastatioN wrote:Take a look here :D http://www.eweek.org/site/DiscoverE/popsicle.shtml
LOL, its my bridge!

Posted: Wed Nov 02, 2005 4:27 am
by mjrpes
duffman91 wrote:
DevastatioN wrote:Take a look here :D http://www.eweek.org/site/DiscoverE/popsicle.shtml
LOL, its my bridge!
No... you stole my bridge idea you patent infringing faghole.

Posted: Wed Nov 02, 2005 5:04 am
by Nightshade
I've got a great idea: How about ToxicDud does SOME OF HIS OWN FUCKING HOMEWORK FOR ONCE?

Posted: Wed Nov 02, 2005 5:38 am
by bitWISE
I made a kickass triangled bridge like your first image but instead of squared supports I triangulated those as well. My deck was made up of three alternating layers and when the glue dried it actually arched. I also stole an assload of glue from everyone else.

Came time to test it and I had one critical flaw...at ONE place in the deck all my alternating panels came together rather than overlapping each other. Damn thing snapped right at that point after around 20 lbs.

Posted: Wed Nov 02, 2005 8:32 am
by MKJ
do your own fucking homework for a change, bitch

Posted: Wed Nov 02, 2005 9:04 am
by chopov
heh, we had this also in first semester at the uni. Gap likewise 50 cm, material was free of choice. I used thin wooden sticks and cardboard for my bridge. It weighed 13 grams and broke at 87kg. That would result in R = 514,8

I won. :icon26:

For the design it is absolutely crucial how the test load is being put to it. At a single point (with a hook or so) or as an "area load" (sp?)?

Posted: Wed Nov 02, 2005 12:33 pm
by Guest
chopov wrote: For the design it is absolutely crucial how the test load is being put to it. At a single point (with a hook or so) or as an "area load" (sp?)?
The load will be put at a single point, like a plug in a hole in the bridge.

Posted: Wed Nov 02, 2005 12:39 pm
by Foo
Toxic, you're fucking dense and will probably never learn anything on your own bat. Shame.

But here's an opportunity anyway:
http://www.bridgebuilder-game.com/downl ... bbdemo.exe

Posted: Wed Nov 02, 2005 1:02 pm
by 4days
duffman91 wrote:Image
that's the same design i used at school (but there wasn't a cock and balls in my schematic). took a few kilos before it broke.

i know a lot of people are taking time in this and the other thread to flame toxic and accuse him of being an imbecilic waste of life, but to be totally reasonable and fair - they're right.

Posted: Wed Nov 02, 2005 1:45 pm
by Ryoki
Hey guys i have a psychology exam tonight, plz help? thx!

Posted: Wed Nov 02, 2005 2:31 pm
by Foo
Ryoki wrote:Hey guys i have a psychology exam tonight, plz help? thx!
http://www.humanmetrics.com/cgi-win/JTypes2.asp

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