I can't figure out the suspension bridge...

[Merthykins]

In the tutorial level, there's another piece of terrain to attach the suspension to. On the level with it in the second world, there's nothing else to attach to. When I try to attach to itself, it fails... Any tips on how the suspension bridge should work?

[Narwhalman02]

There should be two points above the ground for you to attach your suspensions too. If there isn't, you'll have to use your materials to buikld a tower to attach the suspensions too. (If steel is one of your materials I reccomend using that)

[Dry Cactus]

Adding to what Narwhalman02, there is an unwritten rule (which should be written...), making it so that you can create a suspension cord only between pre-existing joints (ie: you can't click on an empty space and create it there)

[Merthykins]

That's what I thought, so I did something like this:
http://steamcommunity.com/sharedfiles/filedetails/?id=474001282

And it just crumbles like this:
http://images.akamai.steamusercontent.com/ugc/445077687928195067/CE78FCC4451CA50D333779380A9926709E46DE6E/

[Dry Cactus]

Weird, would you be able to make an animated GIF using the Share Replay feature, it will then save it on your desktop in the PolyBridgeGIFs folder, or you can also submit it the online gallery, which then appears at http://polybridge.drycactus.com/gallery
Thanks!

[Merthykins]

Sure!
http://i.imgur.com/QaFwHE5.gif

Thanks :)

[Dry Cactus]

The replay looks slightly different than the screenshot.
In the replay it seems the collapse is happening because the main pillar support, on the rock, is a rectangle.
You need to brace that by triangulating the supports.
In general, you want triangles everywhere.
In the screenshot version, also, you have a diamond shape just under the road, where the pillars are, which again will tend to open up and offer little support.
A rectangle means that the whole structure will freely move around (a square can become a diamond shape with little force, but a triangle stays a triangle, unless too much force breaks it)

[Merthykins]

Could you show me a "solved" version of this? I feel really dense, I'm just not getting it :\

[Dry Cactus]

You can find a bunch in the gallery: http://polybridge.drycactus.com/gallery/
Make sure to keep scrolling down the page as it has an "infinite" scrolly loady thingy.

ex: https://i.imgur.com/oL4sROq.gif

[Matt]

Triangles my friend! a structural engineer's best friend! after arches that is :P

Im having trouble explaining clearly but basicaly think of it this way for a triangle to deform and still have all of its segments attached one of the segments has to change size (break or bend) making the triangle a great structural shape.

On the other hand a square deformes easily since nothing keeps the corners from changing angles and thus becoming a parallelogram.

Ugh thats a horrible explanation....

Also you need the rest of the bridge to be there so the weight of the bridge spreads equally :)

[Matt]

Google to the rescue lol [http://www-tc.pbs.org/wgbh/buildingbig/educator/images/spot/activitystrawidea.gif]

[Arjen41]

let me jump in here, every joint(yellow dot) is like a shoulder, it moves however it wants, if you make 3 "shoulders" connected to eachother it cant move in any way whatsoever. and that is why triangles are awesome in this game, only if i could play it D: lol

[Merthykins]

Okay, I think I get it now--thanks everyone! :)