Details, details.

one thing that most teams forget is the max size your bot can be at the start of the match DOESNT mean the robot cannot be standing on its side when the match starts

too many people think the bottom of the outline box MUST be the bottom of the robot

it doesnt

you could build a bot that sits on the field on its side, and at the start of the match it falls sideways onto its wheels

that means you could have a base frame (what were the limits last year?) 3 feet wide and 5 feet long? or 5 feet wide and 3 feet long?

or a circular bot 3 feet in diameter?

this is one time when you literally need to think outside the box.

I remember this year team 19 did that. It was a really amazing thing to see. If anyone saw the Science Channel video, they were the team that was blocked by the Pius Princesses in the semi-finals.

The only problem with such a design is interference from other teams. This year such a thing would be illegal, but who knows what the game will be like next year.

Re: Bot Shape
 

one of the pros of a trianglular base (assuming you also go with a triangular drive train, don't know how you'd go about that though) is that you always keep all wheels in contact with the ground even when going over ramps and things at sharp angles. could be handy if they ever give us a really multi-leveled field with lots of ramped obstacles and stuff...

Gullwing doors are those doors that flod upwards to open, and have a piece of the roof attached to them. There were gullwing doors on the Delorean from Back to the Future. Thats whats he's making reference to.:cool:

In the famous words of the best button pusher ever, Nate Hatch, "The wedge has the edge" :yikes:

from an engineering perspective

given that you want maximum stablilty => widest footprint + low center of gravity

and you want light weight for max acceleration

and you want an enclose suface so nothing can get at your bots inards

then the 'best shape' would be a hemisphere that can turn on its center axis:

1. a sphere has the greatest enclosed volume for amount of material used => light weight
2. a circular chassis cant get cornered or stuck against any object
3. cutting the sphere in half gives you a wide footprint on the floor
4. it would be difficult for other bots to push you around, due to your curved outer hull.

Off-Topic:

Gullwing Doors:


On-Topic:
I think it's a shame that people are saying what is the best, and what is not. To me, the best shape is one that productivly holds all of the pieces that your strategy wants to do. How your wheels are doesn't necessarily have to be what your body shape is.

In 2002, Team 247 wanted to grab all 3 goals. They decided on a triangular shape, with 3 wheels in "crab-style). When all was said and done, weight issues caused the third goal-grabber to be scrapped. How well did it work? Finalists, Semi-Finalists, and Quater-Finalists at 3 regionals, including a 7th seed at one of them. (Note: This was 247's best year)


In 2003, 247 chose against the Triangle design because they wanted to make a wedge that wasn't always out. It had 4 positions, 0º, 45º, 90º and 'Closed'. When at 0º, the robot became an effective wedge that could fit under the bar, and push around teams such as the TechnoCats with seemingly no effort. At 45º it could be used to side-swipe the bins in autonomous to get more stacks downed. At 90º it could block portions of opponents view when strategically needed (such as a cornered bot, driver doesn't know what direction to turn). When closed, the robot had it's small footprint.

By having this mult-purpose wedge, weight was saved giving 247 room to create a suction mechanism, which aslo worked very well.

Also, the 2003 bot, with it's rectangular deisgn, had 3 wheels. That's right, 4 corners, 3 wheels. The layout of the wheels was the same as in 2002, but a different speed shifting style and wheel type.


Sorry this was so long, but my opinion is that your strategy should define your building type. Don't jump to conclusions about things. For example, the hemi-sphere.. using equations it is the best bang-for-your-buck, but if you have no use for a hemi-spherical design to do the job you need, what's the point. Same with every other shape.

Find out what you want to do, without a body design in mind. Then find a body type that suits it well.

I prefer the Hypercube shaped robot. More reading here here and here.

That way you can hide your contraptions in the 4th dimension, and expand your robot size at will :-)
Makes it easier to fit inside the constraint box. Puny FIRST limits only apply to 3 dimensions.

*lays 6x6x6 inch cube on the playing field, match starts and a huge 12x5x7 monster of a robot emerges*
muahahaha

but the outside shape of your bots body IS one of its critical functions how it interacts with the boundarys of the playfield, how suspectable you are to being pushed around, or having your wires ripped out

how suspectable you are to getting pushed into a corner or against a wall where you cant turn to get out

think of a jet aircraft - would you tell an aerospace engineer to lay out the engine, cockpit, and weapons systems, add wing and tail, and then just enclose everything with sheet metal?

obviously not - the outside shape of an aircraft affects its funtionality

and the outside shape of your bot affects how it moves and funtions on the field

and this is one of the things MOST teams forget about.

Thanks for all the toughts guys/gals. There is so much varity and thiught put into each post. That is why i love FIRST it is not about who wins or losses, it is about who helps others more. Thanks again every body:yikes:

Re: Best Body shape?
 

Honestly, I would either have to go with triangular or circular, because then it deflects the force of any oncoming robots better.

If you're aiming to build a robot that pushes other robots, however, rectangular would be better (possibly with a wedge) so you can direct your force over a very large area.

While form typically follows function, in the case of robots, form can determine function.

No, but I would tell him to make sure the body can handle the systems. In an aircraft, form and form of systems defines functionality. A box with engines, weapons, etc. won't fly.

I wouldn't tell the A.E. to design a body for an aircraft, then consider what parts can go where. If they do, 99% likely they will have to redesign the body.

Re-read my thread and my points about 247. Their goals were established, then their body shape. In the case of an military aircraft, some goals are 1) Fly 2) Fly fast 3) As much vision as possible for pilot(s) 4) Provide weapon power.

With those simplistic goals:

1) Body shape must be Balanced and Aero-Dynamicly shaped.
2) Engines must have high power and applicable efficiancy.
3) Cockpit must be in front of plane with windowed casing.
4) Weapon systems must be large enough for tasks to come and be balanced so #1 is not effected.

I didn't say design a body around components. I said to design a body around stategic goals.
Perhaps "pieces" was the wrong word, as that probably dictates direct component use. I meant "ideas", but pieces borderline fits.

Oh, the A-10 Thunderbolt II/ Warhog was designed around the General Electric GAU-8 Avenger 30-mm cannon. And the F4U Corsair was designed around their engines I believe too. HOWEVER, the goal of the design was to use said systems. Like a fast radial piston engine for high speeds was for the F4U. The Avenger 30MM cannon was to provide an increased capability in the aircrafts intended task of close air support, interdiction, and etc. missions.

now back on topic
Rectangle so you can make a "perfect" BLT if nothing else :).
(BLT = Brave Little Toaster). Also a rectangular design makes it easier to manufacture and assemble as its base is really just 90 degree angles.

<goes back to listing supplies to build a BLT in the dorm room>

Hexagon, like our omni bot.