"alibaba.com is a great place to get a very large, low-cost envelope. you can specify materials and envelope thickness with most of the manufacturers. add an Arduino-based blimp controller board, motors, props, maybe an internal…"
"Srikanth, if you are looking for a quadcopter-type, that will be tough, but not impossible and you'd definitely have to build it from scratch with a super-low disc loading. For reference at an extreme end of the scale (human-powered…"