I have been moving to put together a multicopter for a while now. I have been finding differing research on which specs tend to be the most efficient. I feel like many writers reference things I should commonly know and I'm missing something really obvious; like reading a description of an elephant and the author assumes you have seen an elephant but all I picture is a dinosaur (odd analagy sry). SO, this is my first post after trolling around here for three or four years.
I'm seeking guidance on what the Ideal 'copter is and what is cost effectively realistic. This is a hobby not a professional application. I'm looking to put together a machine that I can FPV using a GoPro Hero 2, and can stay aloft a safe 30mins (<crazy?) using autopilot.
My Confusion is regarding how many Kv the motors vs the props vs the frame design. Then batteries and ESCs follow.
Items currently in my inventory:
- Audio/Video tx/rx 5.8Ghz @ 2Watts
- APM 2.6 (compass/GPS in the mail)
- GoPro 2 (AV adapter in the mail)
Design Questions:
- Motors - Multistar 4822-690Kv 22Pole is my best guess from my research. Not Clear on the advantage/disadvantage of the pole count in regards to efficiency. Maybe 2KG AUW
- ESCs- Afro/Turnigy 30A -45A? (Amps are motor dependent but what about the programming?)
- Props - 12x4.7 (Larger is more efficient?) plastic/wood/carbon?
- Frame - My thoughts lean towards a 650mm hex but the real question is quad/hex/oct. The size of the frame seems dependent on motor/Prop selection.
- GoPro Gimbals
- Batteries - I know there is a declining return on the weight vs power. What's best in practice?
- FPV Glasses (Fat Shark? I think i have an OpenHeadTracker MCU that someone posted on here a few years ago -same guy as the OpenOSD i think)
Radio:
- FrSky Traranis X9d - w/ X8R Rx (says its 8/16 Channel - I don't quite get that. It looks like 8)
- Spektrum DX8
I think I have pretty much decided on the X9d. It just seems like the best bang for the buck and I love supporting open source. Pros/Cons options to consider?
So, I'm asking for your IMHO's on and Ideal Multicopter specs (still within the realm of non-Millionaire hobbyists) and then a Realistic Cost Effective Spec that has the appropriate trade-offs needed. Please Feel Free to School me in the basics.
P.S. Not directly related but a parallel project im working on is a mobile tracking station. I salvaged an old electric wheelchair, redid the motor drivers, hooked up a few arduinos. Gonna hook up an APM 2.6 to it and work out the FPV stuff on land first. But I'm getting a great little object tracking camera that im going to incorporate between the ground and air units. On a side note: I live in the middle of the pacific so shipping takes about a month and there is no support on island for much more that what you can get at a home depot. So knowing about little things - like special screws or connectors beforehand is GOLD because it instantly sets a project back a month when I find out too late :)
Replies
It could be worth play with
http://www.ecalc.ch/
30 min looks challenging, 15-20 min more realistic.