Battery Low action request

[chschmid]

[Jdmagoo]

I'm keen

[joebar.rc]

[r0sewhite]

3 cents from my side:

1: there is no right action for a low battery status. It always depends batteries, flight conditions (wind), possible landing places, necessarity to land on or avoid special places (lake, people). A simple RTH is an action that may make beginners feel safe but in fact that's not the case.

2: measuring voltage doesn't tell you how long the craft is still able to stay in the air. Capacity monitoring gives a more useful result if the batteries are reliable. Emcotec additionally monitors the voltage of single cells but the reason is only to detect broken cells so that the oring can exclude a defective battery completely from the circuit. This protects the power circuit from breaking down but it only helps if the remaining batteries have enough capacity to at least land the craft.

3: what Peter told about the "intelligent batteries" sounds very promising but will probably cost a little more than a standard LiPo and thus will only be of interest for professional pilots. Anyway, Peter, please keep me updated on your battery project and when it happens, I would be glad to test a set in our copters.

[Max]

Redundant battery system. No need for "smart" batteries. "Just" a controller to monitor battery state and switch to reserve battery(ies) if primary is low/defective. Like a reserve fuel tank. And maybe it could analyze the spare battery and then if it passes a voltage/load test, engage failsafe/RTH. Sounds like the Emcotec system already does some of that. Of course it would need to be reliable enough to not cause its own problems.

-Max

[chschmid]

Morning Tilman

I agree with you.
A battery redundancy is a very useful thing, but requires a sophisticated HW as your board and two batteries.
The intelligent batteries sound very promissing too but with similar restictions.

IMHO a simple capacity measureing would cover most hobbyist needs at a reasonable cost and at least pevents the craft from crashing due to empty battery.

Futhermore it would be easy to implement into AQ6 and be a good start to collect experiences.

Cheers
Christof

[chschmid]

[sandmen]

On the "batterie project",
we get all this informations (batterie health, capacity, estimatet flight time, and all this things .....) via oneWire.
The electronic, should be removable. So, you don't need to buy always a "new" battery!
Of course, the proce is not for fun flyer, but I think, it will not be too expensive!
peter

[Max]

Sure, some way to get battery data to AQ would be great. It could be used to calculate flight time, transmitted to GCS/OSD, logged, etc. Current is vital of course, and individual cell voltages would be nice. I'd like a way to hook up multiple units to one 1W port, or some way to monitor multiple battery packs (I use individual battery leads to the PDB, not a splitter, so there's no single point to measure current from).

Speaking of battery testing, is there a product out there to do a simple/quick load test on a LiPo? Something at a higher rate than a typical charger/discharger can do, and cheaper. Used those for car batteries back in the day... put a high load on it for a short time and see how much the voltage sags. Not a very sophisticated device... just a variable load and a voltmeter.

-Max

[chschmid]

Hi Peter

As discussed before the intelligent batteries are very interesting. I would take some 4s 6000 for testing purpose as soon as they are available. (or any other sizes to test in my planes.) If you have a list of avilable sizes, please let me know.

As I understood you, this is a project in very early stage. Maybe we can sync the onewire protocols and the data provided with the standalone sensor.

Does the brain also measure the capacity used?

Cheers
Christof