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On location battery rotation?

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I have adapted my I1 to carry auxiliary batteries and am getting consistent average flight times over 20 minutes with room to spare.

Using this setup, how many TBxx batteries would one need to play round robin, recharging and reusing batteries on location with one 100 watt power supply? This should include one flight's-worth of cool down time for previous flight's battery.
 
Or maybe make it clear what you're asking about, since you mention "auxiliary batteries?" at some point, and asking about TBxx (which ones exactly? or do you expect numbers for both?) so we pretty much have no idea of what you want exactly.

That, and you can probably figure it out yourself the same way we'd have to?
 
Plenty of information provided. Its a forum for, y'know, discussion. Like where you talk about things. Things like how many batteries you need to keep in rotation when flying your drone.


But hey, hope you're able to get that sand worked out.
 
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I think what Kilrah means is that there's a lot of variables that we don't have in order to complete the equation for you.
Do you mean TB47's or TB48's
Do you discharge to 30% or to 10%
What kind of temperatures are you working in (a hot battery won't charge till it cools down, and so cold climates can charge again sooner).


I can tell you what I find with my system, which differs from yours massively in that I have dual 180w chargers. But you can use it as a rough guide.

I have 4x TB48's and 1x TB47.
I use 2x 180w chargers.
It's around 12-15 minutes flight time from each TB48 battery and probably about 12mins max from the TB47.
I live in a relatively cool climate, and we're also coming out of winter, so the cool down times are only a matter of minutes and often less.

So assuming a rotation time of 18 minutes per battery.
Assume you start flying at 00:00 hours:

Battery 1 will be flat and be on charger at 00:18 (ready at 01:48)
Battery 2 will be flat and be on charger at 00:36 (ready at 2:06)
Battery 3 will be flat - but you're out of chargers - at 00:54
Battery 4 will be flat - and still no chargers available - at 01:12
Battery 5 will be flat - and no chargers available - at 01:30
with my 5 batteries I'm now dead in the water after just an hour and a half.

Assuming I add one more battery.
Battery 6 will be flat at around 01:48 ... just as the first charger finishes charging, and battery 3 will now go on in its place.
But I still couldn't loop them, even though I finished my last one just as my first one became ready again, because....
Battery 1 will now be in use again and flat at 2:06, just as the second charger finishes.
Battery 2 will now be in use again and flat at 2:24, but battery 3 will not be finished charging until 3:18.
I now have around 54 minutes till battery 3 is done. I'm still way short of looping them perpetually.

So 6 batteries and 2 high wattage chargers, with precision switch overs, would still only get you till about 2:24 before you'll come unstuck and have to wait.
In theory it will only work if you have 6 chargers.
So my answer is that you need 6x high wattage chargers, and 6x TB48's to loop perpetually, but even then I'd probably want a 7th battery and charger, just to give me some buffer for the batteries that take unusually long to charge, or other anomalies, like much shorter turn around times where I'm down and back up in 15 minutes, etc etc.
 
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I think what Kilrah means is that there's a lot of variables that we don't have in order to complete the equation for you.
Do you mean TB47's or TB48's
Do you discharge to 30% or to 10%
What kind of temperatures are you working in (a hot battery won't charge till it cools down, and so cold climates can charge again sooner).


I can tell you what I find with my system, which differs from yours massively in that I have dual 180w chargers. But you can use it as a rough guide.

I have 4x TB48's and 1x TB47.
I use 2x 180w chargers.
It's around 12-15 minutes flight time from each TB48 battery and probably about 12mins max from the TB47.
I live in a relatively cool climate, and we're also coming out of winter, so the cool down times are only a matter of minutes and often less.

So assuming a rotation time of 18 minutes per battery.
Assume you start flying at 00:00 hours:

Battery 1 will be flat and be on charger at 00:18 (ready at 01:48)
Battery 2 will be flat and be on charger at 00:36 (ready at 2:06)
Battery 3 will be flat - but you're out of chargers - at 00:54
Battery 4 will be flat - and still no chargers available - at 01:12
Battery 5 will be flat - and no chargers available - at 01:30
with my 5 batteries I'm now dead in the water after just an hour and a half.

Assuming I add one more battery.
Battery 6 will be flat at around 01:48 ... just as the first charger finishes charging, and battery 3 will now go on in its place.
But I still couldn't loop them, even though I finished my last one just as my first one became ready again, because....
Battery 1 will now be in use again and flat at 2:06, just as the second charger finishes.
Battery 2 will now be in use again and flat at 2:24, but battery 3 will not be finished charging until 3:18.
I now have around 54 minutes till battery 3 is done. I'm still way short of looping them perpetually.

So 6 batteries and 2 high wattage chargers, with precision switch overs, would still only get you till about 2:24 before you'll come unstuck and have to wait.
In theory it will only work if you have 6 chargers.
So my answer is that you need 6x high wattage chargers, and 6x TB48's to loop perpetually.

That is a great reply! Seeing that Pescatoral Pursuit is in Orlando, Florida the wait time between battery cool down will be greater. I struggle with the same issue here in the Ft Myers, Florida area all the time. My batteries get HOT! I try to keep them cool before use by putting them in a cooler that has been chilled overnight, then put them back in a chilled cooler to help the cool off after a flight (probably not recommended) but it works for me. Fortunately we are coming into slightly cooler weather in the next few weeks. If on a day long shoot I will bring all 10 of my TB48's, a portable generator, cooling fans and my smart power charger that charges 4 batteries at once.
 
I have adapted my I1 to carry auxiliary batteries and am getting consistent average flight times over 20 minutes with room to spare.

Using this setup, how many TBxx batteries would one need to play round robin, recharging and reusing batteries on location with one 100 watt power supply? This should include one flight's-worth of cool down time for previous flight's battery.

What size are your additional batteries?
 
... If on a day long shoot I will bring all 10 of my TB48's, a portable generator, cooling fans and my smart power charger that charges 4 batteries at once.

Very jealous. I so want one of those, but I won't sink the AUD$500+ into one until I know what batteries the Inspire 2 will use.
I'd hate to get one and then find that I need a new one to run Inspire-2 batteries.
 
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Thanks for the informative replies. We're starting to get somewhere but it seems neither of you guys engage in the actual process in the field. It is simple math to put pencil to paper and make a static equation, but as often as not, real-life experience is quite different and its that real-life experience is what I am *ahem* angling for.

I intentionally left my particulars vague but with a general understanding of my setup and more importantly, the concept, because
A. I'm sure no one else is using an identical setup, and
B. I was interested in how y'all are getting it done.
C. Not looking for exact figures as much as a general "workability."
A perfectly informative answer could go like: "Tried that. Too much task saturation on site so I have 15 TBXXs."
Maybe it mislead some to post only some of my equipment but it is the viability, experience/ process, and lastly, exact particulars that I am mostly interested in.

Sancap: I have a range of 3C 2200mah to 5200lihvs. One pleasant by-product of flying with auxiliary batteries is that, in sharing the load, primary battery doesn't reach high temperatures and is often barely to moderately warmer than when installed.
 
I engage in this in the field often.
My last shoot was an all day event shooting Inward Bound at Dalmeny. Went through my entire stock of batteries over and over.

I have both a 100w and a 200w solar panel charging dual 120ahr batteries, both running 360w inverters. I run a 180w charger off each inverter, and cycle them through as fast as I can on big shoots. I even have a generator available for shoots on cloudy days. I very much DO do this for real at most of my shoots.
And that's how I know the figures. And how I know I need basically one more battery bare minimum and 2 more to be manageable, and ideally 3 or 4 more just to really know I can crank them through.


Sent from my iPhone using Tapatalk
 
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I engage in this in the field often.
My last shoot was an all day event shooting Inward Bound at Dalmeny. Went through my entire stock of batteries over and over.

I have both a 100w and a 200w solar panel charging dual 120ahr batteries, both running 360w inverters. I run a 180w charger off each inverter, and cycle them through as fast as I can on big shoots. I even have a generator available for shoots on cloudy days. I very much DO do this for real at most of my shoots.
And that's how I know the figures. And how I know I need basically one more battery bare minimum and 2 more to be manageable, and ideally 3 or 4 more just to really know I can crank them through.


Sent from my iPhone using Tapatalk

Thanks. You have helped redirect my strategery.
 
And your iPad.

The iPad proved the biggest problem. Kept switching to my phone for the Inward Bound shoot, and putting the iPad onto one of those 10,000mah pocket batteries that can charge at 2.4A to try and keep it topped up.
Turned it off everytime I wasn't using it but that wasn't enough. I was soon going to be stuffed, because the phone was dying too, but thankfully the wind got up into the high 37-40kmh range and I told them they have enough footage, and I'm grounding. I wouldn't have managed the last couple of hours. If I get many more big ones like that I'll need some other option. Though I admit I didn't start topping up the iPad in the down times soon enough.

I would use the second controller and switch it to master if I had gotten low on the controller. But it was still on 2 out of the 4 lights.


Sent from my iPhone using Tapatalk
 
Well, my answer here will probably be a bit unusual, but if you're REALLY looking for continuous long-duration flight, you're flying the wrong type of aircraft with the Inspire. By the time you get done with mods, extra batteries, chargers, tunes and tweaks, making sure your iPads don't melt, and the like -- you'de be better off with a fixed wing or hybrid VTOL airframe.
 
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Well, my answer here will probably be a bit unusual, but if you're REALLY looking for continuous long-duration flight, you're flying the wrong type of aircraft with the Inspire. By the time you get done with mods, extra batteries, chargers, tunes and tweaks, making sure your iPads don't melt, and the like -- you'de be better off with a fixed wing or hybrid VTOL airframe.

Can you give us some examples of the aircraft you mention? I am always open to different products.
 
You beat me to the punch, Ezookiel. About 3 batteries with the Parrot Disco will maintain semi-continuous flight (you have to land to change batteries). Flight time is 45 minutes to an hour (depending on wind conditions and the way you fly it) and charge time is 55 minutes. I have the Disco and can tell you all about it from a personal flying standpoint. If cost-is-no-object :) I've been lusting after the Alti dual-hybrid VTOL UAS (www.altiuas.com), but that'll set you back around $70K fully kitted-out, the Disco at about $1600 is a *bit* more reasonable, but it doesn't hover...

Cheers
 
But for clarity, here is my First Disco flight, which did NOT end well. This ain't a quadrotor.

It was in auto-land mode and hit a stand of trees. Fortunately it's built like a brick s*** house, and neither the tree nor the drone was harmed by the collision. I just put it back together and flew it again a couple more times!

 
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Depends what the purpose of the flights is. If the goal is to get good footage the Disco is pretty much unusable.
 

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