LEGO Mindstorms BlimpBot

Using an RCX, 3 Motors, the Infrared Remote, Large trash bags, and lots of helium, my son and I created a steerable blimp.

Two of the motors controlled propellers (made from a LEGO propeller with larger blades made out of packaging plastic). The third motor controlled the tilt of the two propellers.

Each propeller can be separately controlled. For example, to rotate the craft, one propeller would be driven forward and the other backward.

Metal washers were used as ballast to try to achieve neutral bouyancy so the propellers could be used to raise or lower the craft as well as move about the room. Helium leaked out of the trash bags fairly quickly so the ballast and to be frequently adjusted.

With one load of helium, we had about 2 hours of flight time (starting with a lot of ballast and then removing it bit by bit over the two hours).

The use of the Infrared remote was a bit of a challenge as the controls were not very intuitive (e.g., frequently tilting the rotors in the wrong direction). Also, maintaining the line-of-site needed for the remote was a challenge.

In my next version, I'm planning to make the following changes:

- Use an NXT instead of an RCX and use bluetooth to remotely control the craft.

- Set up more intuitive controls.

- Replace the trash bags with one large mylar envelope. This should greatly increase the flight time from hours to days or even weeks.

- Set up one of the propellers to have the opposite pitch to have the two props cancel each other out when spinning in a vertical position.

- Add sensors and program the NXT for independent control.

Category:

Science & Technology

Tags:

• LEGO
• Mindstorms
• blimp
• flight
• RCX
• remote

[Freddythethird]

where did u get all the helium? I know albertsons inflates balloons, but do you have to pay? and how much?

[bzupke]

Many party type stores will rent helium tanks. You'll need a big tank if you want to lift an RCX or NXT.

[meinblockpunkteu]

That is sweet!

How did you build the air-screws?

[bzupke]

I cut out larger prop blades from some plastic that was part of the packaging for some electronics. I then glued the blades to a couple of LEGO props using a glue gun. I increased the pitch of the blades by first gluing a small piece of cardboard (like from a cereal box) on the LEGO props.

[xilliah]

where do you get helium?

[bzupke]

You should be able to get it from most party stores (like Party City).

[pjwithbread8]

not really. just a little more flexible sometimes. but not really.

[magicwill25]

That is amazing. Very cool. I can't wait to see the next one!

[zc630]

I think RTX is more fun than NXT

[TLoremTIpsumT]

i wanna fly awaaaaay

i love your idea. nicely done.

[javlin100]

thats amazing!

u should replace the binbags with big ballons

[sdrfgvrfgvsfravgdsvS]

I think about your creation that is the fis of the lego that has been put in the sky!!!

[billyboy385]

its realy dark in your house and song rocks!

[ronaldmcrae]

and I also like the fact that you took the time to write a decent length story about the project. I expect you'll find NXT makes life a bit easier for your next build but somehow I find that that makes it a bit less challenging!