is there a height restriction for a structure buit in the pits?
that all depends on the venue and there safety rules MOE 365 had a 30ft tower last year and as long as we were safe about it no one said anything. but if you do a high structure remember that it must be bolted to something very secure at the bottom so it wont tip over and kill the team next to or behind you. also have GP and don’t put up anything that is offensive or could block other teams views of screens or something like that.
I love the sig kyle! and your pic is broken… i think some plastic broke… MORE ZIP TIES!
30 feet?! What could you possibly need that would be 30 feet high?
Anyway, yeah, height shouldn’t be a problem unless you’re constructing something like a giant screen infront of one of the monitors just so everyone can watch your team play DDR in the pits.
While there generally isn’t much said about the height restriction, keep in mind that you have to bring all this stuff with you, and set it up, and take it down. For a lot of teams, a simple “pit area canopy” is perfectly sufficient. Your materials need to be within reach of the pit crew so that work between matches is efficient and safe.
A really tall structure may take up more room, meaning you may inhibit on the paths/roads in the pits and such things, and that’s not GP.
i fogot to mention that we made to tower out of old carpet streatches or something like that was light and easy to take with us and it was also not to large and took up about 2 feet sq at the base in the inside of the corner of our pit so it woundnt bother anyone.
i couldn’t see what i’m talking about doing being more than 10ft tall
Just make sure the ceiling height is more than that and you should be fine.
And to whoever asked about what you need a 30 foot tower for, well, it functioned as a sort of lighthouse. Besides that, it’s just cool in general to build a massive thing in your pit.
Whatever you’re doing make sure it’s sectional or telescopic so depending on the height at the venue you can change your structures height. The interior height may not be the factor either, depending on where your pit is you may be limited by venue lighting, ductwork or support beams.
If you’re doing a single column for a sign for example, it would be best to attach the bottom to a piece of plywood that extends out from around the base. Just don’t allow it to extend into the isles or adjacent pits.
Whatever you do just don’t drill holes in the floor and install Redheads. Venues will fine you for that sort of thing! 
Since we must fit behind the line in the end, does all of the robot need to fit bedind the line or most of it?
You should make sure you’re able to fit the complete robot in your pit. I’ve seen teams working on robots partially out in the aisles but it is a safety violation and FIRST can say something about it. Why take the chance?