Being honest with you, every time I tried to take a flight one or the other props just tends to slip off and come out flying. I have to tighten them strongly everytime. I will order good ones right away along with the battery. Also, I have 2 options for the battery either a 25C or a 35C. Will 25C be enough for my craft with my configuration? Available amperage at 25C is 82.5 A.
You should replace the motors. The reference motor for that craft is a 2212-920kV. Buy motors with threaded shaft bells. Better props would help also. They don’t have to be carbon fiber.
25C is fine
Oh, and the battery? I should continue with this? Either i can buy a battery or 4 Motors. That is why asked you that is the battery a problem? Because once I buy motors i wont be able to buy a battery. I have limited funds from the college pool to complete the project. I hope you understand. If you want I can try another flight tommorrow for better undersatnding of what’s wrong with the quad. Maybe something else arises.
Before you start buying anything specially if your budget is so limited find the root cause of your problem.
So if you have just a new 3S 2200mAh battery it is not normal that the voltage is going directly down to 8.2 V if the battery is fully charged.
Did you charge the battery before first flight?
Did you used the same charger as before with the old battery?
What kind of charger is it?
As the battery is going down to 8.2 V, did you checked all single cells voltage at the same time?
Did you measured the current?
Is the current of all 4 motors nearly the same.
And still there is the open question which C-rating should your battery has.
From where or whom you bought the battery. Ask the supplier for a datasheet.
@Juergen-Fahlbusch Sorry for the misunderstanding that battery is not new it a 3 month old battery, that was used in my previous kit. And still can fly that kit 1 craft easily.
Yes sir, I did charge my battery through the skyrc b6 charger to a 100% until it came to 12.6 volts. All 3 cells were 4.20 4.19 4.20. Right now the battery is at 3.97 3.90 3.95 after the latest crash.
No, the charger I have has been only used with this battery. No other battery has been charged by it. Just got it 2 days back.
It is a SkyRC IMAX B6 V2 60W Charger pic attached below
No, do you mean after removing it from the quad and checking it with a battery checker? Or during the flight?
No, I did not measure the current. I will tommorrow if that’s a case. A youtube video might help right? Or naything specefic?
For your reference I have this battery. PFA pic.
Unlike this battery pic, my C rating doesn’t have a mark of what C rating does it have.
This is a local battery that we buy from the local market. This isn’t a company sort of.
Also I never take my throttle past 20-30 % because at 30% itself it topples and never lift offs.
If your battery has no mark at the C-rate we have to assume it has the minimum 25C rate.
You say if you use this battery directly on the other frame it is working well.
Did you check this after you got the above mentioned problem?
Are the two drones comparable?
If yes, than your problem is probably not directly a battery problem
So try to run your problematic drone and measure the voltage of all cells (one after the other) during motors running under load.
I did not check this after the problem has come. Actually this battery was at my University where i used it with my 1st kit. this was 2 weeks back. Now, I have got it sanctioned for my own kit for home. And yes the two drones are exactly identical. As I used the term. There were kits ordered. So that kit is working stable. Now I want this one to work. Replacing the battery would affect? I mean i don’t know. Are there specific batteries which ones configuried with one pixhawk cannot be used in another?
Alright, Tommorow I will run a test with video that i can later attach here, and test the individual voltage of all cells when throttle is at 100%. Also, do note the HUD always says battery 1 is low. So this isn’t cell 1 right? I also tried to reset the pixhawk, from the side hard reset button, but all i could see that the params were as it is when i came back to check them? Is this normal? Even after hard resetting? Also, do note that 2 weeks ago, before bringing it home, the last flight it came crashing down hard? Can this cause damgae to pixhawk? Like is there a way to diagnose that are the internal IMU and sensors working in pixhawk?
Regards
Try to check the battery again with the first drone.
If you have two identical drones than you have good possibilities to exchange components between the two and find the problem.
The FC is only checking the voltage of the complete battery not the single cells (if connectd correct)
The FC uses all batteries it is not limited to one special battery.
Did you told us about the hard crash of your drone? Yes, such a crash can damage any electronic.
Yes, I did post logs in the thread. But that was due to a bad battery who’s cell 2 died. I will do a battery test on this battery with all above mentioned testing. And will update you shortly.
Yes, we thought that it crashed due to the battery. But you didn’t checked why the first battery dies. So probably this dead of the battery wasn’t the root cause.
Thats why I say don’t buy anything new if you don’t now the root cause.
Okay, understood. For now i should do the testing on the battery before buying a new one right?
Okay, I am posting the video with the individual voltage of all cells under 100% throttle.
Also, these are the messages i get in the hud.
2-03-2024 02:00:40 PM : EKF3 IMU0 MAG0 initial yaw alignment complete
02-03-2024 02:00:40 PM : EKF3 IMU0 tilt alignment complete
02-03-2024 02:00:38 PM : EKF3 IMU0 initialised
02-03-2024 02:00:38 PM : EKF3 IMU0 forced reset
https://drive.google.com/drive/folders/1Gv4Bb8WlMuELfAB41wAF7tMBjxq7MjGl
The video shows a total value of around 11,2 V. If this is under full load it seems ok.
Was this test with props mounted and drone fixed on the ground?
What was the reading of voltage by the FC during this test, shows it nearly the same?
Which drone and which FC was tested?
All this I can’t taken out of the video.
Also it is better for all if you posted directly the values instead of a large video.
No, this test was without props with only motors running at full throttle.
The FC reported it 11.19 volts.
My current drone on which I am working on with Pixhawk 2.4.8. (My kit). I do not have access to my college anymore.
My apologoies for posting a direct video.
Also, just did another flight,
Log File C:\Users\adity\AppData\Local\Temp\tmpE35B.tmp.log
Size (kb) 2491.796875
No of lines 32708
Duration 0:00:00
Vehicletype ArduCopter
Firmware Version V4.4.4
Firmware Hash db53a28f
Hardware Type
Free Mem 0
Skipped Lines 0
Test: Autotune = UNKNOWN - No ATUN log data
Test: Brownout = GOOD -
Test: Compass = WARN - Moderate change in mag_field (25.46%)
Max mag field length (589.61) > recommended (550.00)
Test: Dupe Log Data = GOOD -
Test: Empty = GOOD -
Test: Event/Failsafe = GOOD -
Test: GPS = UNKNOWN - No GPS log data
Test: IMU Mismatch = NA -
Test: Motor Balance = UNKNOWN - ‘QUAD/X’
Test: NaNs = FAIL - Found NaN in CTUN.TAlt
Found NaN in CTUN.DSAlt
Test: OpticalFlow = FAIL - ‘FLOW_FXSCALER’ not found
Test: Parameters = FAIL - ‘MAG_ENABLE’ not found
Test: PM = UNKNOWN - ‘NLoop’
Test: Pitch/Roll = GOOD -
Test: Thrust = GOOD -
Test: VCC = UNKNOWN - No CURR log data
I have posted another log in the drive and a new video of the flight. The quad seems to take off only to totally wobble like a boat in the sea. Also, the battery monitor wasn’t setup when I came back to check in the log analysis. My bad.
Also, I know @dkemxr told me to get rid of the tether, but last time I’ve had terrible accidents trying to get it in the air, the quad is not my property, so I cannot take risks.
You will have to take that risk. The tether adversely affects how loop control functions.
Auto analysis is useless, don’t bother posting its results.
Okay dave, I won’t use tether from now.Also, I have bought another battery, it says 2200 mah 3S 11.1volt 80C battery. Did you find anything in the log? I fear my pixhawk has gone bad. Is there a way to check?
Regards
All I see in that video is the craft lifting off and being tugged by those tethers. Take it to an open area and make another attempt after following these instructions:
Go to Mission Planners Setup>Mandatory Hardware>Initial Tune Parameters and enter 10" props and 3S battery and write the resulting parameters. Then set these manually:
INS_ACCEL_FILTER,10
INS_LOG_BAT_MASK,1
INS_LOG_BAT_OPT,4
PSC_ACCZ_I,0.7
PSC_ACCZ_P,0.35
Don’t baby the throttle on take off. Give it enough to rapidly get it off the ground a meter or so. If successful hover for ~1 minute land and post a link to that log file.
Okay sir, WIll do that first thing tomorrow morning and update you on the same.
All I see in that video is the craft lifting off and being tugged by those tethers. Take it to an open area and make another attempt after following these instructions:
Go to Mission Planners Setup>Mandatory Hardware>Initial Tune Parameters and enter 10" props and 3S battery and write the resulting parameters. Then set these manually:
INS_ACCEL_FILTER,10
INS_LOG_BAT_MASK,1
INS_LOG_BAT_OPT,4
PSC_ACCZ_I,0.7
PSC_ACCZ_P,0.35
Don’t baby the throttle on take off. Give it enough to rapidly get it off the ground a meter or so. If succesful hover for ~1 minute land and post a link to that log.
There is no GPS in this log. What happened to that?
@dkemxr, you told me to not worry about the GPS, so removed it from this flight. Should I connect with it? I thought GPS might be the issue seeing so many compass error warnings. I will connect GPS in tomorrow’s flight if that’s the case.