I am a hobbyist and using hexacopter for flying purpose. I am using avionics 850KV motor with 1045 props. As per calculation it can take upto 4.5 Kg of load ,so i made the lift-off weight 4.3 kg that consist of 2342 gm of vehicle with power station and remaining is load. A 4S Lipo battery is used on board. When i am flying it after 15 sec my battery fail safe enabled and it landed down my hexa. But the lipo battery tester i kept on battery was telling a high value of current then it was showing on mission planner. please help me find the solution of this problem.
my flight log is available here :
Blog is not the place
Loiter fails you see below why, and it’s an hexa with four motors?
but the take off weight should be maximum a half of lift in kg, better a quarter for better efficiency. try this to begin http://ecalc.ch/
Test: Compass = FAIL - Large change in mag_field (397.72%)
Max mag field length (1113.22) > recommended (550.00)
Test: IMU Mismatch = FAIL - Check vibration or accelerometer calibration. (Mismatch: 2.94, WARN: 0.75, FAIL: 1.50)
Test: Motor Balance = GOOD - Motor channel averages = [1261, 1256, 1261, 1273]
can you post a Photo of the hexa
I have moved your post to Hardware Multirotors so a more appropriate ordinance gets to see it and respond.
If you are using a 4S as you say then it was already flat at take off with only 11.8V.
Even for a 3S thats not great.
Your sucking 40A to 50A out of it so it gave all it could while it could.
As @edge540T mentioned, your flying a Quad, not a Hex.
Your RCout is very strange, have you calibrated everything?
4.3kg on a quad running 850Kv on 3S with 10x4.5 props is way too heavy.
I would agree with @edge540T, redo your calculations and build.
It didn’t have a chance.
Sir as i mentioned that it is a hexa not a quad.sorry for uploading the wrong file. i am re uploading the file please check.
Thanks, the log relates to what you describe now.
Your battery is just not up to the job.
The moment you power up the voltage drops from 16.4 to 12.5 and slowly declines from there.
Thats only 3.125v per cell which is well below minimum volts, and it declines from there.
I usually have 3.3v as the minimum and that is only because my failsafe is Land.
If you want a failsafe of RTL then you would set it to around 3.5v per cell.
You will need to re-evaluate your battery.
Your copter is also quite overweight or underpowered (same thing).
Even i was expecting the same but i asked my battery provider to provide me the voltage vs soc curve of battery but they don’t have such data.
thanks for your help sir.
I hope i will get your helping hand to shape me up my hobby as a drone operator.
HI , i am using a hexa with 4s battery with total lift-off weight is 3329 gm. my flight performance was normal and vehicle did not shown any anomaly apart from the voltage behavior. During the flight my voltage was increasing instead of decrease. What could be the possible reason behind this ? can any one explain what it is and how to correct it ?
here is the link of my flight log.
That link doesn’t work
try this please : https://drive.google.com/open?id=1K61cLXDjmQ7I62bGG7vOCMttCs-WCT6u
You seem to have misconfigured your voltage measurement.
That does not look right for battery voltage movement.
Does it correlate with direct battery voltage measurements?
It is tracking current too closely.
Have you set voltage to the same pin as current?
Sir, today i flew my drone with a 4S ,10000 mAh battery with fully charge at the time of take off. What i have found that my battery discharged soo quickly. CAn you tell me that how it isi happening ?
One more question i am having that if i will charge my same battery at 2 Amp and at 4 Amp then in which case my battery provide power for a longer time. I am attaching a flight log.
To see if your battery is actually discharging quickly, is not the flight time but how many mAh you put back in when you charge it.
This battery curve is only a little better than the last.
As you can see the voltage takes a big dive as soon as you start to take off.
You are using only 20 to 25 Amps in hover, so your 10000mAh battery is operating at only 2C to 2.5C.
Something is not right here.
Either the batteries are inappropriate for the job.
Are they LiPo?
Or your current sensor is giving wrong readings.
The most basic LiPo should be capable of 10C which would give you 100Amps of useful power.
So after a short flight when the battery FS kicks in and it lands, how mAh do you put back into it to fully charged?
The accepted charge rate for a LiPo is 1C, or 1 x it’s capacity, which in this case would be 10Amps.
Charging it at 2 Amps or 4 Amps will make no difference to it’s performance.
Oh. I will try to charge it at 10 amps, monitor the discharge pattern and inform you after a flight.
Just out of curiosity!, Which Charger you use ?
my charger is vista ap 606. Sir i am having a TATTU battery of 4S1P with 10000 mAh capacity. will you please suggest me the charging and discharging current for my battery to get the best performance of battery
I think ,that charger’s capacity is 6Amps.
What is your power supply’s ratings?
If it is 5amp, set the charger to 5amps [5000mah] & 4S to charge.ie 1/2 C.
Discharge. -set the lipo alarm or failsafe to 3.5 or 3.6V for the first few cycles.
so mean to say that my charger is not enough to properly charge my battery ??