Motors and Escs

Hi Marco,

You can download the dataflash log using MP.

I’m back again… and now my drone is broken… In PosHold the drone came off the ground but after a few seconds it shot forward and he hit the ground on one arm and the arm broke.

This is the dataflash log analyze of the first fly

Blockquote
Log File C:\Users\pigre\AppData\Local\Temp\tmp416A.tmp.log
Size (kb) 9741.6318359375
No of lines 115015
Duration 0:11:13
Vehicletype ArduCopter
Firmware Version V3.6.11
Firmware Hash 296c62b3
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 (124.14%)
Max mag field length (703.86) > recommended (550.00)
Test: Dupe Log Data = GOOD -
Test: Empty = GOOD -
Test: Event/Failsafe = FAIL - ERRs found: FS_BATT CRASH
Test: GPS = FAIL - Min satellites: 0, Max HDop: 99.99
Test: IMU Mismatch = NA -
Test: Motor Balance = GOOD - Motor channel averages = [1602, 1642, 1607, 1597]
Average motor output = 1612
Difference between min and max motor averages = 45
Test: NaNs = FAIL - Found NaN in CTUN.TAlt
Found NaN in CTUN.DSAlt
Test: OpticalFlow = FAIL - FAIL: no optical flow data
Test: Parameters = FAIL - ‘THR_MIN’ not found
Test: PM = GOOD -
Test: Pitch/Roll = UNKNOWN - Unknown mode in TestPitchRollCoupling: SMART_RTL
Test: Thrust = GOOD -
Test: VCC = UNKNOWN - No CURR log data

This is the flight of this day

Blockquote
Log File C:\Users\pigre\AppData\Local\Temp\tmp6F12.tmp.log
Size (kb) 113.3955078125
No of lines 1926
Duration 0:00:02
Vehicletype ArduCopter
Firmware Version V3.6.11
Firmware Hash 296c62b3
Hardware Type
Free Mem 0
Skipped Lines 0
Test: Autotune = UNKNOWN - No ATUN log data
Test: Brownout = GOOD -
Test: Compass = GOOD - mag_field interference within limits (9.05%)
Test: Dupe Log Data = GOOD -
Test: Empty = FAIL - Empty log? Throttle never above 20%
Test: Event/Failsafe = GOOD -
Test: GPS = GOOD -
Test: IMU Mismatch = NA -
Test: Motor Balance = GOOD - Motor channel averages = [1034, 1034, 1034, 1034]
Average motor output = 1034
Difference between min and max motor averages = 0
Test: NaNs = FAIL - Found NaN in CTUN.DSAlt
Test: OpticalFlow = FAIL - FAIL: no optical flow data
Test: Parameters = FAIL - ‘THR_MIN’ not found
Test: PM = UNKNOWN - No PM log data
Test: Pitch/Roll = GOOD -
Test: Thrust = GOOD -
Test: VCC = UNKNOWN - No CURR log data

We would need the bin file itself, not the output of the auto analyze tool.

First flight

30 17-05-2020 19-28-12.bin.log (9.5 MB)

Second flight with crash

32 21-05-2020 19-00-50.bin (76 KB)

I am not at home till sunday, so I can not look at the log right now.

Hi Marco,

Unfortunately, the 2nd log is empty.

I’ve looked into the log from the 1st flight, and it seems that the flight controller experienced quite high vibrations:

Do you use any anti-vibration mount on your drone? May I ask you to share hardware setup photos?

TY @tatiana.andreeva for your fast answer. Your assistance is really appreciated.

Following the damage to the Frame, I decided to redesign from scratch the hardware and now the drone is completely disassembled.

This is the image of the frame that contains the raspberry and the navio2 card. The two cards are supported by two gray rubber strips and you can also see the foam that I have fixed on the barometer.

That’s all for now. I will put the photo of the new assembled drone as soon as the components arrive.

Hi Marco,

Keep us posted on your build progress :slightly_smiling_face:

I’m here… I had some difficulty in finding the components due to the health emergency that is hitting hard in Italy.

I decidet to change completely the frame off the drone. In first time I used a 330mm frame but now I have passed to a 650mm frame where I can easily install the components in order to guarantee them adequate protection.

Unfortunately I confused the motor connections and now I have to redo them in order to have the right alternation between clockwise and counterclockwise rotation.

I also think I will remove the PiCamera and mount an action camera.

I take this opportunity to ask a question … Is there a way to replicate the Navio 2 status LED? I have connected an RGB Led strip to the drone and would like to understand if I can use it to have greater visibility of the state of the Drone in flight.

Hi,
in regards to pi-camera: It’s well known that pi camera and its cable cause issues with interference. - Hence you can check online for info on how to best shield camera and cable. (i.e. copper tape, or at least aluminium foil wrapped around cable and rear of camera with insulation in between.)
But if you are using other camera than that may solve this issue anyway.

Vibration as noted by Tatiana: Besides the anti-vibration mounts for the controller, you should also ensure the propellers are balanced. If that is not the case all the mounts for the controller may not solve problems.

Stopping time of the propellers: This needs to be done via programming the ESC’s according to instructions of your ESC’s - Sometimes a download is required as not all ESC’s come with printed instructions. Most ESC’s have a function called “motor -break”. This will instantly stop the propeller spinning once motors are turned of.

Electro Magnetic interference: You’ve mentioned in an earlier post that you live next to a High Voltate EE Station. Please don’t fly anywhere near that as the magnetic field from the station will alomost certainly cause all sort of problems in regards to build in compass and /or also cause problems with GPS reception.

TY @anon31534460 for your complete answer. I have already shield the RaspiCam cable with aluminium paper but I want switch to an action camera for a more beatiful video and images.

For the vibration I have chosen to change drone frame and I will also change the propellers with better quality propellers.

Finally, the point concerning the programming of the ESCs is very interesting.
How can we work on the programming of the ESCs? Via Ardupilot? with other flight control it is possible to connect via USB and try with BL Heli but I don’t know if it is feasible with Navio2.

Common ESC is card programmable (easy if you purchased the card with the ESC) or RC programmable, using your RC tx and a receiver, following the instruction specific to the ESC and not missing tones…

BLHeli are easy to set but RC passtrought don’t work on Navio. As Navio is not compatible with DShot and Oneshot doesn’t work since arducopter 3.6 appearance, no need to go this way unless Emlid solve the Oneshot bug.

Thanks @mlebret for information…

Now I think I’m ready for the first flight.

First flight done… First crash accomplished.

During the flight I stopped in stationary flight over a tree and suddenly the drone fell over it.

This is the data log file.

2020-06-09 17-39-02.bin (3.9 MB)

And this is a video that i did after take-off in loiter mode. So at first glance the drone looked very stable.

Well done, some improvement needed.

There is one or more motors not flat. One group of motors (3-4) need more power to maintain heading.

Your rig is too heavy or underpowered. Average RC out PWM is around 1700. You need more RPM (4S battery) or larger propellers if possible (check motor + ESC data).

Your crash: maybe one ESC overheat…

Hi,

one tip for the future: Sound is really helpful to find certain problems, so just upload the video with the actual audio track, no music.

Thanks a lot @mlebret for your help. I had noticed this problem in fact, especially the motor 3, tends to go in protection for the achievement of the minimum voltage and it stops like in a crash.

What I don’t understand is why only two engines and not all 4. The Escs are identical and the engines also. They are powered by the same branch plate connected to the battery.

@schuermannsebastian thank you for the advice but in the video my little daughter’s voice was heard too much and I didn’t like to keep it

Ok. I know this “problem”, too!

I do a test today with a 4S battery and without propellers.

what I noticed is that, if I push the joysticks of the radio control to full scale, the motors slow down or increase speed according to the command, and this is correct, but if I hold the position for 3 seconds the engine 3 and the engine 4 slow down until it stops, generating the crash message.

I’m also attaching this data log
35 12-06-2020 22-34-23.bin.log (303.2 KB)

Isn’t that a problem with adjusting some parameters within Ardupilot?

Thanks.

When you can’t understand what’s happen on the ground is time to take off.

I have done an other flight. I have been very cautious and have had no accidents.

In this flight i used again the battery Lipo 3S - 5000 mAh 50c but I installed 10" propellers.

This is the graph relating to the outputs. At the beginning they were out of phase as in the previous flight but then they almost aligned on the same values.

I also made this video leaving the original audio this time. I could not do too many maneuvers because I had a remote control and a cell phone in my hand at the same time.