I have a question about the Li-Po battery options for the upcoming Arducopter quad kit. I was reading the Aeroquad tutorial to get an idea of what I should buy and they recommend using the HobbyKing 4400 mAh for the Aeroquad. However, I have seen some project quads on this forum using the 2200mAh Li-Po’s.
I’m wondering if the Arducopter carrying a 500 gram payload (camera gear, etc) is better off with the lighter 2200mAh or could it handle the additional (152g) weight of the 4400 mAh battery? I’m know there is a point of diminishing returns where adding more battery capacity (weight) is not worth the return in flight time.
I am using both 2200mAh and 4400mAh batteries on my ArduCopter without any problems. Ok i have not been having extra 500g payload onboard but I cannot see any reasons why it would not handle it. It can lift quite much.
I'd say on this point bigger issue is that do you want to put heavy camera on it or not. I would not put any expensive equipment on it yet due our software is still early beta and there are a some stability issues still on software. It is not yet save enough for that.
After we get our latest software back to as stable as it was earlier, I will do some payload tests with it. Currently we are working on some heavy changes on code and code structure to make future path better...
I'm still waiting for the kit to be released, so I won't be flying for weeks. I plan to do at least 10-20 hours of test flights before putting on any camera equipment. Thanks again for all the hard work from you and the team, it is very much appreciated.
In on your expert opinion, what do you think is the maximum flying weight of the arducopter based on the current combination of motors, esc, frame, etc of the pre-order kit (i.e, arducpter components + payload)?
If you don't see any reason for the arducopter not to lift the extra 652g indicated by Mike, how much more you think can the quad carry as you did indicate It can lift quite much?
I have not tested it's maximum lift capacity and well in overall it's a bit deceiving to give one. It is more or less question of how long you want to fly with your designed weight.
MK prove that they can fly MK about 45 minutes. Yeah sure you can but on what conditions. They had their test on indoor badminton/tennis hall, no moving around, no flying around just basically hovering. And with what equipment, I bet it was rather light and just minimal electronics. Ok 45 is still great achievement.
As said, I have not made maximum payload tests but I have tested motors what we use on our kit's. Those 850kv motors with ArduCopter propellers can lift 433gr each motor with 50% throttle, with 75% throttle they lift 855gr. at 50% current was 3.4Amps with 3S LiPo, 75% 9Amp. (100% thr, 1095gr, 12.2Amp)
Current motors are good allrounders but I'm still looking more and better motors every day...
ArduCopter kit (i will confirm total later after all official parts has arrived) is around 850-900 gr with full electronics and full flying weight with 2200 mAh flightmax lipo was around 1010gr if i remember correctly. I have flown same quad with 1400gr flying weight and it takes of like rocket and flies nice. (camera/mount + bigger batt onboard)
If you have heavy payload, you need to tune your PID settings to make it really stable. Everything depends on how heavy and how far GC is from originals so it will be difficult to say how to tune at this point. My 1010 / 1400 gr flights were done with same settings.
After we get more ArduCopters up in sky, we can start forming better hand rules for different weights and camera/other setups.
With bigger ArduCopter motors (optional) you can get even more lift due their maximum thrust is about 1350gr with 12x45 propeller. So really rough maximum for them would be 5.4 Kilos with 100% throttle.. Ok well you would need to provide 80Amp too to achieve that power :)
I should have detailed weight information etc around end of next week, then all latest parts should be at "home".
Just to provide a background, my main interest is fitting the arducopter with a camera system able to get downward looking images hoping to extract the R and IR bands of the images for vegetation health monitoring. I'm more into getting to the right altitude and maintaining a hover above a certain area (this is where the GPS hold comes handy). Flying time may not be as long as people from MK as you've indicated as it will become a competition between battery weight and time in air.
Based on the figures you've given, is it a simple matter of multiplying the lift figure by 4. I mean thrust at 50, 75 and 100% throttle will mean theoretical lift capability of 1732, 3420 and 4380g respectively. Using rough estimation, given the ESC used on the kit to be 20amps extrapolated lift value could be around 2200g. Of course lots of other factors can come into play that can drive this value down.
I'm afraid I am not familiar with the weight to thrust ratio so correct me if I'm not getting it.
The figure of 2200g lifting weight I've indicated in my earlier post is presumably based on a 1:2 weight thrust ratio or is it the other way around of thrust to weight ratio based on your reply?
If its the former, so the thrust of the motor included in the kit is 4400g (total thrust that is with individual motor ~ 1100g) or if the latter, 1100g (/4 ~ 275g per motor)! There's no spec included in the motor being included in the kit (I could be wrong) and searching for AC 2830-358 motor did not yield any information.