Hovercraft?

I have tried looking in last year’s manual but couldn’t find anything… Are there any rules against building a hovercraft robot?

I can’t think of a rule disallowing hovercrafts. But, you would need to make sure the blades were not exposed and could not become exposed.

I dont see why you couldnt. Whats the advantage though?

Just remember, hovercrafts work with as little friction as possible. You’re going to get pushed around like nothing else, and have trouble moving yourself in the first place.

My Advanced Engineering class is building a hovercraft this year…as i side note

But i would not recommed it…like somebody said before…no friction=no pushing power and very little climbing ability unlesss you have a pretty big moter and the hovercraft would be prone to problems like breaking parts or ripping skirts

I dont know, I could see a hybrid between a hover craft and a single ball-drive (that touches the floor) having some advantages on a FIRST robot

or a 2 wheel skid steering robot, with a hover front end, instead of castors or low friction plates?

as for being pushed around, then you shut the blowers off, you are parked Baby!

rules don’t say you can’t do it i think you should if you can pull it off in a compediitive robot design it would be awesome

try taking a look at these
http://www.chiefdelphi.com/media/photos/tags/hovercraft

I dont see why you couldnt. Whats the advantage though?

Hovercraft can be agile. They are very fast (capable of attaining speeds unlimited by the drive motors) but lack any kind of pushing power other than what is provided by the fans (which are designed to accumulate speed rather than accelerate rapidly).

We proposed that we could possibly use a three skirt design with a tough rubber/canvas armoring which would allow for great stability, maneuverability, and durability though increasing the friction on the ground somewhat.

However, a true pro to the hovercraft design is that the supports are deflatable, turning a robot into a mobile shooting platform and a three skirt design could also allow for ball pickup. A broad base at ground level provides the perfect base for an accurate shot into a goal (which would have complimented our two wheel automatic aiming system).

My Advanced Engineering class is building a hovercraft this year…as i side note

I wish I had you as a teacher :frowning:

We proposed experimenting with a hovercraft last year during the design stages, or at least building a small test machine using cpu fans to determine if it would be a suitable design for a goal shooter.

While we were excited about the idea, our mentors were much more closed minded and decided to shoot the idea down as soon as it was proposed without much reason other than a “Well I don’t want to make a hovercraft and I have a degree so I get to decide.” attitude. I’m not sure some of our team mates ever got over that night when our ideas were dismissed as ludicrous.

Are there any rules against building a hovercraft robot?

I would advise you to be wary with the hovercraft design. You’d have to have some pretty open minded mentors to support such a radical design. :slight_smile:

Um, getting the speed is very unlikely on the field… you’d need room to accellerate. And, with the mecanum drive train 868 developed this year, i’d be surprised to see much of any robot out race it
( :wink: not to brag or boast… it even got us in trouble once, in auton, the programmers screwed up, and instead of going in our intended pattern, we got the switch construct wrong and instead went forward full speed… took us about 3 seconds to get from the furthest back square, to the opposite sides wall. We hit it so hard that it knocked the controllers off the shelf, the controller went so far it hit the knees of the other drivers… :eek: )

more relevent, a hovercraft isn’t realistic because to get it floating, and keep it floating, you’d need a heck of alot of air… and i’m pretty sure that’d drain your batteries too quickly

depends on the surface you are hovering over.

A flat hard covered floor would not let much air leak out. All you need to do is replace the air that is escaping.

pressure would be lower than you might think. If the skirt area is 2 by 3 feet, thats 864 square inches

if your robot weighs 120 lbs, you need 120 pounds distributed under that area.

120 / 864 = 0.138 pounds per square inch (above the air pressure in the room)

that is not very much air pressure to lift a bot!

didn’t think of it that way… interesting (hmm… maybe we should use a hover craft? :stuck_out_tongue: )

Would emptying your pneumatics cylinders be sufficient?

For ramming balls into a goal using a rubber skirt as a bumper… it might just work and would be able to attain speeds much higher than most of the bots on the field just on principle that it lacks significant amounts of friction. :slight_smile:

Can you imagine that thing anchoring down to shoot though O_o

more relevent, a hovercraft isn’t realistic because to get it floating, and keep it floating, you’d need a heck of alot of air… and i’m pretty sure that’d drain your batteries too quickly

We never quite got to test the actual design, but a hovercraft not required to jump hoops and speed over rocky ground might have been reasonable depending on what we were using.

Apparently, not much air is required to pass through the skirt to keep it on some form of cushion of air. Preferably, we would want a skirt that would drag along the ground under the bot somewhat to prevent the skirts from turning and would also require less air to keep the skirts inflated.

The two that Adam and Jamie built used vacuum cleaner motors to keep the design levitating. Hovercraft should, in theory, be lighter than a robot with a drivetrain and wheels and perhaps could have more efficiently used higher rpm motors such as those used for fans.

At a minimum, it would have been nice if we could have actually tested our designs. :slight_smile:

Trouble is TG, the three skirt design is one of the very few ways you can really move the silly box. In doing so, you also limit yourself to moving about 3 directions, which change at any given time (and with low friction, change easily). As well, you’ve got to protect your entire bot when it’s on a tilt, as well as other bots from it. We don’t need our hovercraft putting a metal bar through an electronics board, and we don’t need a corner of another robot tangling with the hovercraft. The pressure needs to be maintained, which with inflating and deflating requires a lot of power. You’ve got many more moving parts, damage to protect yourself and others from, a lot more work from a programming perspective, as well as a hard time controlling the thing.

Too much work, trouble, and possible disqualification for the gain.

Sufficient for what, exactly? There are lot of designs and depending on which you’re specifically talking about, it means different things.

If you’ve got a no-skirt or open-skirt approach, you need a constant amount of air being pushed down to keep the robot pushed up. A no skirt approach requires enough air to lift your robot being forced down at all times. An open skirt requires only enough air to replace the air that’s escaping, to maintain pressure while air escapes. Depending on how you work your pneumatics… shrug

Closed skirts are fun because you don’t actually have to do any air work if you don’t want to. By the robot, any way. You could pressurize them back in your stall, attach them, and run. What propels the silly bot is up to you, preferably more air though :stuck_out_tongue: If you’re going with inflating-deflating closed skirts, as mentioned by TG, you’re going to need to be able to extract and force air into the skirts at all times. Imagine having to control the size of 3 balloons on your robot. It’s not exactly easy, but doable.

well, don’t 6-wheel designs tilt somewhat too (with the “dipped” wheels)?
and, for that matter, any bot with center of gravity issues is likely to tilt/fall over too.

Who knows, maybe it’ll be a water game, and hovercrafts will be all the rage :smiley:

The difference between tilting a bit, and tilting as much as 60-70 degrees :wink:

edit: DO I HEAR ROBOTIC WATER POLO?!?!?! :smiley:

lol. :smiley:

60-70 degrees? thats not even possible :smiley:

If the air bubble you’re riding on is low enough to the ground, it shouldn’t be that much of a problem. A hovercraft is still a hovercraft if you’re floating 1/32 in off the ground, or 20 feet off the ground. The less you’re off the ground, the less you can (really) tilt.

Besides, if someone pushes you, you won’t really tilt, as much as float away…

Unless you’re deflating and inflating skirts, which will naturally induce tilt. Though depending on your height, 60-70 degrees is quite impossible or possible :stuck_out_tongue: I was thinking about a robot higher off the ground than I realized at the time would be practical.

But you guys are all forgetting, this year is going to be a water game :stuck_out_tongue:

In all seriousness, as cool as a hovercarft would be, the robot’s pushing power would be so impaired that you couldn’t go through with the design- competitively. But, it would be awesome enough that doing well with it wouldn’t matter :wink:

haha, it probably would “inspire” a new award, or at least automatically get the Xerox Creativity Award.