hovering robot

[MangoBot]

so, i got a ok sized topic on the flying stuff, but what do you guys think of a inner tube with a big fan pushing air down wards pushing air out making it 'float' on a flat surface and if the inner tube floated it could go on water, then having a servos on each side so that it could go in water or having something to rotate the fan in the push the water and air differently would also be a way to move, it would be cool to have some systems to sense if it is on land or water(like using a depth sensor and when there is no water it knows it is on ground), and maybe a mercury tilt switch to sense if it might tip over. any input on this idea would be good.

[SmAsH]

rather buy a premade rc hovercraft and use it as a starting platform...
you seem to be asking questions relating to all kinds of different projects, rather focus on one... or you WILL fail.

as for the mercury tilt switch, it would be a horrible choice... rather use a gyro/accelerometer...
with a mercury tilt switch it is either half way tipped over or not tipped over at all...
therefore you cannot measure how far over the robot is, you would want something that can give an angle instead of all the way or not all the way...

[MangoBot]

im actually focusing on just one mainly and that is with the line following robot using IC's and i am getting pretty far, i just can't find out how to wire the IC's together, but i am working on it, and i am a student so dont have that much money to spend on it, im saving up to buy the pieces

[Razor Concepts]

You will need counter-rotating fans so that the tube won't spin around.

[apc3161]

rather buy a premade rc hovercraft and use it as a starting platform...

I agree with this 100%. From an mech/aero eng. grad student, implementing stuff like that will be nothing but headaches. Better to just take advantage of the headaches other people had to go through to get a product like a RC hovercraft to the market.

[MangoBot]

google how to make a hovercraft and you can see how easy it is, a inner tube, a plywood board, and tape.

[SmAsH]

building it is one thing, making it actually work well is another.

[jamort]

as smash said...
another thing is the fact that i know one fan will just make it spin... two countering each other it wont spin but i think you will probably need about four to get a stable flight... youll get a lot farther if you LISTEN and buy a prebuild rc and expirement see how it works then make use of a microcontroller on it... sorry if theres typos im on a phone

[wil.hamilton]

google how to make a hovercraft and you can see how easy it is, a inner tube, a plywood board, and tape.

take a word of advice from someone who has worked on a couple of those, you dont want to build a robot that way
its very hard to make work and isn't reliable at all, all we managed to do was get something that sort of floated sometimes, you'd be much further ahead to buy an RC hovercraft, plus it would be more to the scale you want

[MangoBot]

i didnt want to make i a robot just something small and fun like 1 ft by 1 ft with a prety small inflateable tube pump

[wil.hamilton]

reminds me of a challenge i did once where we were trying to build an (almost) all lego hovercraft, i've seen a few that worked, the only non-lego component was the plastic they used for the "skirt".

So, you wanted to just make a small "floating" platform? not necessarily have it maneuverable, just floating?

[MangoBot]

well it would so hover around on the floor but with no purpose, and then eventually make a bigger one with 2 or more fans and adjust there speed to change direction, or turn on off to have everything rotate around it, like for tubes all attached to a main thing in the center, where they all make themselves hover, instead of one really big floating platform

[wil.hamilton]

if you plan on doing any sort of maneuvering with a hover craft, i would just go w/ an RC one, there is a lot of engineering involved in making a hover craft, let alone one that can be steered.  even if you do build a successful hover platform, there is no guarantee that you would be able to upscale it and it would still work.  also, the addition of the extra weight for maneuvering and control elements could displace the balance enough that it would not function again.