($50) No Take-off at full throttle

hello everybody,

i have a $50 reward if you can help me. i am having issues taking off with quadcopter. every time i go to take off, no matter what flight mode, (loiter - stabilized etc) my drone will only lift off the ground about 1 foot and then crash. i am running a lumenier 60A Esc to 4 - 620Kv motors with a 6000Mah Li-ion battery. the drone weights 3.5lbs. why am i experiencing this issue? i have confirmed: all motors mapped correctly and spinning the correct way. for some reason, the drone takes off at about 40% throttle and my telemetry says at 10-12A, and then, as i increase the throttle to 60% and 100%, the drone, still outputs 10-12A. help! i can PayPal someone $50 if we figure it out. thanks everyone!

Hi

If it possible, please, send your logs of flight with this problem, it will be useful. Also, did you make test in acro mode?

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What battery voltage, what actual motors and what prop size and pitch? What protocol do the ESC’s use and out of curiosity what Flight Controller.

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here is what the “log analyzer”:

Log File C:\Users\FlySk\AppData\Local\Temp\tmp2C04.tmp.log

Size (kb) 38626.771484375

No of lines 461581

Duration 0:11:59

Vehicletype ArduCopter

Firmware Version V4.6.3

Firmware Hash 92b0cd78

Hardware Type

Free Mem 0

Skipped Lines 0

Test: Autotune = UNKNOWN - No ATUN log data
Test: Brownout = GOOD -
Test: Compass = FAIL - Large change in mag_field (115.54%)
Max mag field length (982.76) > recommended (550.00)

Test: Dupe Log Data = GOOD -
Test: Empty = GOOD -
Test: Event/Failsafe = FAIL - ERRs found: FS_THR GPS_GLITCH
Test: GPS = UNKNOWN - join() takes exactly one argument (2 given)
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

or are you asking for the .bin file? also, i am upping the price to $50 if you can help me solve the issue. and no, i did not test it in acro mode, only loiter, stabilized, and gps poshold.

i am using a Pixhawk 6X. motors are brotherhobby avengers 2816-620KV using gemfam 1050 (10x3x4.5) running dshot600. and when i start up the quad, the battery sits about 24,2V but sags down anywhere from 1/2 - 1 volt.

.bin file is large to send, but if you give me your Gmail i can send it to you?

The log analyzer is outdated and should likely be removed from our software. Use a file sharing service like Google Drive or Dropbox to share the log file itself.

Your first flight(s) should only be in stabilize mode. Using any other will almost certainly not help and could be catastrophic, especially given your observations to date.

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Near the bottom of this link is how to download your .bin files. Upload them to Google drive and share it with us…

Also upload photos of your build, this can be really helpful.

@Yuri_Rage is right, only stabilize mode for first few flights. I say first few so you can get data like, hover throttle, notch filter settings and other things.

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Before the log file is available, allow me to make a guessing theory because i think it’s not neccessary

it’s clear that lifting a 3.5 lb weight with only 10-12 amps is likely impossible.And then, if you say that even at 100% throttle, it’s still 10-12 amps. I can conclude that your current meter is not functional.

This confirms that the crash was due to the ESC’s “Low Voltage Cutoff.”

because i suspect the battery monitor are not functional at all as it should so the voltage actually SAG with really deep

what li-ion battery do you use?

Which GPS are you using and is it placed close to power lines. Try changing the positon of GPS

Pure speculation and not likely causal. I wouldn’t suggest making blind physical changes without a decent log analysis.

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hmm i was making my assumptions due to this…..

Then you are also assuming a colocated GPS and external compass. There isn’t enough information at hand to warrant making physical changes.

Have you ensured your props are in correctly? I am also in the process of tuning a drone and the first time we tried to fly it, it sort of didn’t gain altitude and only seemed to hover due to ground effect. We are using those cheap collet type motors and it turns out, we installed the bush on top of the prop rather than below it and this lead to the props slipping on the shaft so that it could not bite the air.

Assuming you are not using collet type props, also just ensure that the props are the right way around. I’m not talking about swapping CW with CCW but about a flipped propeller. i.e, the top and bottom of a prop might look similar but there is a difference.

Other than this, I would also recommend the default parameters except for essential ones that you should change.

Does your drone gain altitude at full throttle even though not at the expected rate?

here is access to the google drive with the .bin in it. note taken, i will try fly with stabilized mode next couple attempts.

i see. but additionally, what i mean to say is that at 60% throttle and at %100 throttle the drone still outputs the same amount of power - even when throttle is increased.

the drone weighs about 2.5lbs now. i thought the same thing about that, but i turned off the “low voltage cut off” and it didnt change anything.

currenlty running a 1yr old lumenier 6000mah battery

yes. i currently have 2gps. one internal and 1 external. but both are about 1 -2 inches from high voltage power lines. that wouldn’t cause it to take off though right?

IMPORTANT to note that the full system worked earlier with a different ESC. i was running a large PDB to 4 separate ESCs earlier and each ESC to a motor. now that i have switched to this lumenier 60a esc i cant take off. the issue is only arising now.

yes i have made that mistake before haha. I can confirm that is not the issue in this case.

Ask again, what ESC firmware does it use?

not 100% sure what the esc is running.. but my FC is outputting dshot600 which seems to run the motors fine. should i try like a dshot 1200 or something?