I have now set up my battery charger power supply unit with a cable long enough to supply power for my small quad copter for inside testing. This will save the life of the batteries as well avoid the hassle of swapping them over constantly for when doing PID tuning etc. Only thing its not powerful enough to fly my X8 quad and trips the over load at about 29amps. Ill try see if ii will run my hex next. Here is the video of the small quad run
https://www.youtube.com/watch?v=PM4oZEulyqg&feature=youtu.be
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1 guess Anmh :)
...And...What will happen if the power supply from AC socket suddenly lost...?
TS, I do get what your say and yes a lead-acid battery would work for sure and will no doubt run my larger copters. The point of the exercise is not to be doing extreme flying maneuvers, but just to use it for playing around with PIDs and learning how they affect the flight of the copter as well as fine tune the auto trim. So far what Ive done is working really well and is achieving what I set it up for. When I take them out for a fly using the lipos its nearly the same as when I did the tuning using the 12v lead. I'm going try out a 24volt PSU on my larger copters and see how that works.
Not true Crashpilot. And to Papachristos. The theory sounds good, but its not what Ive found happening on the ground in really life mate. The voltage at the PSU is 12.3 volts and at the copter its 11.85v. so not a big drop. I also have done some really good PID tuning using this and its working fine once Ive taken it out to fly. It might not be perfect but its a whole lot easier than all the issues you have to face trying to tune the PIDs outdoors. Firstly its rare to have completely still wind condition outdoor to do the tuning and then you have the battery running down where you don't want to be doing the tuning when its very low which gives unreliable results. At least this is a constant power supply to to work as a bench mark were as Lipo power supply fluctuates during use. Using the PSU it great for doing the auto the trim and really good to learn how much each PID affects the behavior of the copter and get it fine tuned. There is not a whole lot of difference when I fly it on the lead to when I take it out. I even open the door to my apartment and I get a good breeze blowing through to test how it reacts in wind conditions. The convenience s not having to swap batteries over all the time and you can play around with the PIDs for hours. I think good variable power supply for this will be worth the money considering the amount of battery life it will save long term as well.
A 1000W computer supply should produce 12V at enough amps to do it. Those are a lot more than a battery, starting at $110 + $10 tax + $10 shipping. It would be useful to have indefinite hovering of an indoor camera, light, or ceiling fan that could follow a person.
I doubt that indoor PIDs (by wire or with lipos) can be used outdoors in fast forward flight and sharp turns. BTW perhaps we can do a "car battery lift" competition instead of the silly "beerlift" competition.......
The unit I have is just a cheap 12v PSU that I use to power my Battery charger. I tested it on my hex and its just not quite enough voltage to get it off the ground. The voltage reading on Mission Planner while its running is about 11.5 to 11.85 volts so the drop in voltage is not a lot.The max amps gets up to around 35 to 38amps.
Hawhoo, not a bad idea except part the reason I wanted this is to help preserve my lipos battery life.
Very interesting. In Japan we have a requirement to provide 100 hours of flight records (for professional UAVs). Now those need to be with a complete set-up including battery but I've been thinking that a similar set-up to what you have would be useful for long term testing to see what tends to break first (escs, autopilot, motors, prop mounts, etc). thanks for the info on issues that would likely come up.
Point of advice from someone working with a UAV powered from a power supply for initial indoor trial runs:
The cables have minimal resistance to dc current, BUT for current with sinusoidal harmonics their 'complex resistance' is proportional to impedance times the frequency.
The ESCs work in a switching way, @ high frequencies (8 kHz,16 kHz etc) so unfortunately 'composite resistance' manifests itself in a significant voltage drop along the cable
You can notice this if you check the voltage that actually arrives at the copter with a Multimeter while it is operating at the Throttle values you use for hover. While the PSU keeps 12V at its output, because of the aforementioned voltage drop along the wires you should notice a voltage much lower than 12V at the copter side.
And it's not an issue of how powerful your PSU is, because it will always output 12V, the amperage will only differ.
So all in all longer wires means larger voltage drop. But you can't actually work with short ones either. So if you really want to try this approach you will probably need an adjustable voltage psu which are kind of costly, if you also want to go high in amperage.
Additionally to that, yes, the cables have a dampening effect on the copter's response. Also if you manage to fly one of your copters (a lightweight one) at a lower arriving voltage (say 10.5 Volts), be aware that your PID params won't be reliable because the ESCs (actually the combination ESC+Motor+Propeller) have significantly different responses at different voltages.
Hope I added info which will be of some use 2 u
I tried that when I first started out, with a PC power supply for my quad. Not nearly enough power. What kind of battery charger power supply are you using? I think a car battery charger/starter would have enough juice to run any multicopter.
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