autonomous blimp

The original plan was to build two battle blimps that used sonic to ovoid objects and infra- red to find each other, a direct hit from the nose would count as a hit and if the blimp hit anything else on any other part of its body it would be a crash. Sadly when the balloon turned up it was obvious that i wasnt going to two in the same room and having just moved house and being near xmas i was short of money, so the blimp became an autonomous bot and all but two sensors were changed to sharp ir and i removed one that looked down in front of it and changed the code to make the bot drop and use its front ir to see if it can fly under an obstruction. I only have 1 short vid and the bots sensors were not set up so it just kept flying into the wall and the blimp has sprung a leak now and because its to big for my house i wont bother fixing it, it was going to have a short life any way, it needs to be topped up every couple of days just to keep it floating but for anyone else who wants to build one dont use ir stick with sonic sensors the bot moves fast and the range on the ir sensors is too short even when pulsing the motors to slow it down it will still hit walls. if you order this balloon your balloon can lift close to 200g but you will be close to springing a leak, i put less gas in mine and it had neutral bouency lifting 140g of which 25g was ballast. http://www.rctoys.com/rc-toys-and-parts/MACH-ZENV-SILVER/RC-PARTS-BLIMP-HELIUM-BALLOON-ENVELOPE.html for the small motors and battery's this place is by far the best and cheapest http://www.atomicworkshop.co.uk/catalog/