Alexmos 32bit


Ronan

Member
I'm using pole count 14 for all 3 motors... which is what it was set as the default profile for this gimbal...
 

gtranquilla

RadioActive
if you are not getting any IC2 polling errors and you are holding the assembly steady, then it is possible that the three wires are not connected from the motor to the BGC correctly or the motor direction is set opposite to that required in the software.
Another possibility is that the yaw port, e.g., the FET on the yaw motor is damaged or is overloaded or there is not enough current available from your power supply.
 

Ronan

Member
Power is fine, it's what i was told to use for my setup by the builder of the gimbal. I haven't couched any of the wires so i think they should be fine.

I'm going to try to rebalance the yaw axis. If it's not balanced properly i think it could explain why the yaw axis freaks out.
 

Ronan

Member
Ahhhh i ALMOST have it! No more problems, except it doesn't point forward! Which settings let me adjust where 'forward' is, without messing with anything else?

Settings:
2dvvbr.jpg

http://oi57.tinypic.com/2dvvbr.jpg
 

gtranquilla

RadioActive
Ronan,
I assumed you were using the latest firmware which is: 2.42b7
not b6.....
First you have to replace your GUI with the latest - from the BaseCAM web site.

I think you will find it works a bit better.
 

Ronan

Member
That's weird i thought the gimbal was updated too... I'll do it right now I have also noticed that the gimbal is vibrating/humming a bit, introducing some vibration in the footage.

Ronan,
I assumed you were using the latest firmware which is: 2.42b7
not b6.....
First you have to replace your GUI with the latest - from the BaseCAM web site.

I think you will find it works a bit better.

Edit: WOWWWWWWWWWWW What a difference! It's leveled, barely any humming (if any), everything works great! *saves settings*

Thank you for all of the help :) Last question: Are my POWER setting too high? The gimbal weights 700g the camera 500g (maximum camera weight is 900g), using 2 iFlight 4008 motors that have been reminded for pitch & roll, and a big iPower GBM5208H for yaw.

Edit 2: Spoke too soon... the gimbal yaw likes to drift a bit, and takes FOR EVER to go back to facing forward when i spin my hex around...
 
Last edited by a moderator:

gtranquilla

RadioActive
How is your Yaw IMU mounted? Above or below the Yaw motor?

Yaw drift tends to be an indication that the Yaw IMU gyros need to be recalibrated..... they drift a lot.
Also you should find that the yaw drift is reduced when you have the BGC configured for heading versus follow mode.
Follow mode may continue to be a challenge for some time yet with respect to Multirotor application..... the yaw IMU is not intelligent enough to work out wind related disturbances nor remember where North is.

Can't tell you where to go with the power settings as I use a very light Hero GoPro3+ Black so all settings are quite different.
However the auto-tuning should take your power settings into account (whatever they may be).

It is wise to stick with the GBM5208H yaw axis motor because it carries the most weight and has to handle greater angular momentum.
 

Ronan

Member
I have the board mounted on the vertical 'rear arm' with the lipo. The other board is mounted on the bottom of the plate, which is of course located bellow the yaw motor.

Is there a specific/better way when i CALIB.ACC and CALIB.GYRO to give better results?

Thanks :)
 

gtranquilla

RadioActive
I have the board mounted on the vertical 'rear arm' with the lipo. The other board is mounted on the bottom of the plate, which is of course located bellow the yaw motor.

Is there a specific/better way when i CALIB.ACC and CALIB.GYRO to give better results?

Thanks :)
I have to dig into that again tonight..... forgotten a few detailed steps.
Best to avoid recalibrating the accelerometers after they have been done correctly.
Just recalibrate the gyros.....

Also with remote control of pitch and yaw, adjust them to various angles and listen for any buzzing at specific angles. If you hear any, it is a resonant frequency that needs to be dialed out. To determine which frequency, install an app on your smart phone or program on your PC that is called a spectrum analyser...... several are free for PCs.
The program will use your device microphone to listen to your MR. You should see a peak in the spectrum at the frequency you need to dial out. Once you know the frequency, use your BGC GUI to set up a notch filter for that frequency...... it will nullify the buzzing so that your camera will not show the vibes in your photos/videos.
 

Ronan

Member
I have to dig into that again tonight..... forgotten a few detailed steps.
Best to avoid recalibrating the accelerometers after they have been done correctly.
Just recalibrate the gyros.....

Also with remote control of pitch and yaw, adjust them to various angles and listen for any buzzing at specific angles. If you hear any, it is a resonant frequency that needs to be dialed out. To determine which frequency, install an app on your smart phone or program on your PC that is called a spectrum analyser...... several are free for PCs.
The program will use your device microphone to listen to your MR. You should see a peak in the spectrum at the frequency you need to dial out. Once you know the frequency, use your BGC GUI to set up a notch filter for that frequency...... it will nullify the buzzing so that your camera will not show the vibes in your photos/videos.

Great i'll do that. I had heard about being able to setup a filter, which is pretty handy!
 

Ronan

Member
[MENTION=6734]gtranquilla[/MENTION] Hey mate, i'm still getting drift of the yaw axis... After about 3-4 minutes, the camera doesn't point forward anymore, it's already made almost 200 degree turn (slow & steady).

Still a gyro issue?

Both the acc and gyro calibration is a pain... I have to 'block' the gimbal so it points perfectly forward and is level, do the acc calib and then i need to immobilize the whole thing to do the gyro... i think i'm not doing it right...

I'm so close though... darn!
 

gtranquilla

RadioActive
I don't see to have such issues unless I am in "follow" mode which I try to avoid. I stick with "heading" mode.

Assuming your IMUs are precisely mounted as per the instructions, there is no inbalance on any axis, and precisely calibrated and the BGC function set to "Heading" mode you should rarely, if ever, experience any problems with yaw drift.
Also once you accurately complete the 6 point accelerometer calibration, you should avoid doing it again as there is no need to. If you do repeat the basic accelerometer calibration you will undo your hard work with the 6 point calibration.

Also configure your BGC to automatically complete gyro calibration during boot-up.....
hold your camera steady in the heading position for a couple of seconds during bootup then let it go to complete self-stabilization on the 3 axes.
 

gtranquilla

RadioActive
I just upgraded to the new firmware version 2.43 b6 from previous 2.42 b7 and noticed that the GUI has removed the RC control of Yaw motor.....
Do you happen to know why and/or where it went?

Otherwise the system works fine.

[MENTION=6734]gtranquilla[/MENTION] Hey mate, i'm still getting drift of the yaw axis... After about 3-4 minutes, the camera doesn't point forward anymore, it's already made almost 200 degree turn (slow & steady).

Still a gyro issue?





Both the acc and gyro calibration is a pain... I have to 'block' the gimbal so it points perfectly forward and is level, do the acc calib and then i need to immobilize the whole thing to do the gyro... i think i'm not doing it right...

I'm so close though... darn!
 

I had issues with mine for a while. One issues I am still having is the horizon and the pitch act like it has a small amount of follow. A hard bank and the horizon does not stay level. If I go forward into the wind the pitch on the camera does not stay level. On the ground its a mixed bag. Not sure what is going on. No follow enabled.




As for the vibration I did that the pid settings adjusted will get rid of most of it, but I had one part of 45 degree down that I could not get rid of. I found that the larger motors on the DYS near the IMU generated some magnetic field that cause this. I moved the IMU away from the motor that it was next to and the problem went away.
 

vulcan2go

Member
I just upgraded to the new firmware version 2.43 b6 from previous 2.42 b7 and noticed that the GUI has removed the RC control of Yaw motor.....
Do you happen to know why and/or where it went?

Otherwise the system works fine.
I'm using 2.5 firmware now but I'm pretty sure that the GUI for your version has an expanded page in the RC control tab - just scroll down and you should see it
 

I adjusted the Gyro thrust higher and found it helped a lot, but maxing this setting out to 255 It has a very very tiny amount. WHY? I understand this setting as a hybrid of processing of the gyro and accelerometer. The last video I did looked ok to use except the yaw has a chatter to sligthly.
 

Laurenceh-b

New Member

Hope the link works. Are these motors cogging properly? If you turn the sound up you can hear that there are lots of small cogging clicks. The motors were working fine but not now. they no longer have any torque, don't respond to a change in power, reverse direction, number of poles when i enter different values in the gui. the motors themselves seem to be fine. (correct resistance between phases) Anyone know what's going on here? they stabilise the gimbal but just have very little torque.
 

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