understanding the numbers

Started by Animal brown, July 19, 2017, 11:33:09 PM

Previous topic - Next topic

Animal brown

Hi
   I am interested if anyone has a link that would give information that would help explain how to understand the numbers and features displayed on an osd (im using cyclops storm).
I am fairly new to fpv have just started flying with a new set up and am wanting to get comfortable with my system and in particular learn to understand what the battery levels and rssi etc are telling me so I can make sure I don't leave myself to far out with a lack of battery and so on.
Im feeling my way at the moment going between line of sight and fpv with a friend spotting for me but am spending more and more time in the goggles and would like to push out a little further but safely.
I have spent a lot of time searching for answers but have only found a few hints here and there.
all the best steve


Animal brown

Hi Steve W
               I already have the manual what im really looking for is just how to understand things like at what voltage should I be returning on landing etc. I can't seem to find a page that talks about it too much. I did find one on here where members talked about 10.5v, 10.3v but that was about it.
http://www.fpvhub.com/index.php?topic=15665.0

FPVSteve

#3
Well it depends what battery you're using.

3.3v per cell is the absolute minimum for a lipo, so you should be looking to land above 9.9v (on 3 cells) or 13.2v (for 4 cell) - but I wouldn't go that far, I'd be aiming for 10.2v or higher on 3 cell, or 13.6v on 4 cell.

However the more throttle you're applying, the more amps will be coming out of the battery so your voltage will drop - if you reduce throttle the voltage will recover. So you need to find a balance - if you're cruising (i.e. low power) and the voltage is approaching the minimum, it's probably time to land ASAP. If you're on climb out and at full throttle then the voltage will be reading low - so monitor it  to prevent it from going too low, then ease off the throttle and you'll see the true battery voltage remaining.

This is just something you'll get familiar with the more you fly and no two batteries behalf the same.

Basically... if you're cruising and you're approaching the minimum level, come home. If you're climbing and approaching the minimum voltage, ease off the throttle and see where you're at - if it doesn't come back up, come home. If it does, estimate how far you can go. Make sure you fly upwind though so if you run out of power the wind will push you home :)

Loopdreams

Just one thing, do not trust the Storm's "amps used" display.  It's made of lies.

Billy_boy_2010

Some of the numbers on OSDs/autopilot are accurate. Others less so. Some can be calibrated to make them more accurate.

The location to home and distance are IMO the most important and these are always pretty accurate  (provided you waited for a decent number of satellites and set home correctly).

The voltage is normally pretty good. Remember voltage drops if you're taxing the battery in a faster model- so will frequently recover a bit on landing/throttle off. The mah use is frequently way off. Don't rely on it unless you know it's accurate.

Rules of thumb are you shouldn't exhaust a battery- keep 20% of it's capacity in reserve. And don't drop the voltage too low- keep 3.6 volts per cell minimum. Ideally a bit more.

RSSI can be a bit of a curse. It's easy to obsess over it and it can hamper the experience.

Billy_boy_2010

If you're going to push the distance a bit- do it on a fresh battery. Fly upwind so the return journey is easier. Make sure you have RTH set so if you do lose signal you can get it back. Make sure its failsafe settings are set to RTH. Easy :)

Animal brown

Thanks Billy_boy have everything set and failsafes all working just waiting for some weather. Have managed just under 3km recently which was fun and my set up worked as it should.
                       

















Billy_boy_2010

Quote from: Animal brown on September 09, 2017, 07:15:31 PM
Thanks Billy_boy have everything set and failsafes all working just waiting for some weather. Have managed just under 3km recently which was fun and my set up worked as it should.
                     

Ah you're nearly there then.

First step is flying with the plane out of earshot.

After that it's a question of how much money you're prepared to spend on kit and how easily bored you get. Long range can be quite dull.

Animal brown

yeah, the out of earshot thing was a bit weird the first time it happened but the second time I was expecting it so didn't worry as much.
I posted my first flight a few weeks ago. was only around 1.7km but was fun. I have also maidened my mini talon which was even more fun. Just wish the weather would play ball so I could get out again