It was working fine before though... That's what has me puzzled...
Heck now it doesn't even know it's front from back...
Alexmos 32bit
- Thread starter Ronan
- Start date
It was working fine before though... That's what has me puzzled...
Heck now it doesn't even know it's front from back...
SMP
Member
In the Alex GUI - On the yaw axis is the little red dot still or does it keep rotating? When your Yaw goes back and forth 2 inches to either direction how is your gimbal being supported? In other words, is the gimbal moving or is your multi moving.
Strange but true, roll the yaw motor connection into the Alex board by 180 degrees. Yes that's plugged in opposite of your roll and tilt pinout. Try it
Strange but true, roll the yaw motor connection into the Alex board by 180 degrees. Yes that's plugged in opposite of your roll and tilt pinout. Try it
In the Alex GUI - On the yaw axis is the little red dot still or does it keep rotating? When your Yaw goes back and forth 2 inches to either direction how is your gimbal being supported? In other words, is the gimbal moving or is your multi moving.
Strange but true, roll the yaw motor connection into the Alex board by 180 degrees. Yes that's plugged in opposite of your roll and tilt pinout. Try it
I'm using a gimbal stand. The same stand i used when i originally got the gimbal.
In the GUI the little yaw red dot keeps moving back and forth, at the same time as the YAW axis. Sometimes the YAW axis doesn't move back and forth, it simply vibrates (and the moment i move it starts moving back and forth violently).
I can't 'flip' the yaw plug because of the casing.
Honestly... to me it looks like the YAW axis needs to be calibrated... but i'v done all the auto calibration's a few time's, i even went back to the original profile it came with... nothing helps...
I must be missing something...
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gtranquilla
RadioActive
The Basecam forum site provides some user input. And somewhere it does indicate a need to sometimes switch the pins around or flip over the 3 wire motor connection cable. I shortened my and rebuilt the 3 pin cable connection. I also went thru the extensive IMU calibrations for each IMU on each axis using a T-Motor box for mounting the IMUs.......
Don't kid yourself..... these need extreme due diligence.... there is no quick fix. But once you get it under control it suddenly seems so easy.
Don't kid yourself..... these need extreme due diligence.... there is no quick fix. But once you get it under control it suddenly seems so easy.
gtranquilla
RadioActive
My 3 axis BGC is mounted on a Cinestar 8 such that the camera as well as the tripod landing legs rotate on the yaw axis. In my case I suspend my MR in a sling and hold the MR airframe at 90 degrees to allow the Yaw axis to freely rotate. If it tends to rotate to one position, I reduce the weight on that side and/or add small lead weights to the opposite side. When it is 100% balanced I return the MR to the level position in the sling and then begin the PID loop tuning for the yaw axis.
gtranquilla
RadioActive
it's all in the documentation.
smartaerials
Member
Hi guys!
I just bough http://tienda.stockrc.com/epages/eb0140.sf/es_ES/?ObjectPath=/Shops/eb0140/Products/P001-2
It has Alexmos V.3 in it and after some intensive tunning I have it running quite good, the only problema I m having is with te ROLL axis, in quick Sharp moves it holds good but in a prolonged side move t will start to drift,first to on side the to the other..Any Ideas??
I just bough http://tienda.stockrc.com/epages/eb0140.sf/es_ES/?ObjectPath=/Shops/eb0140/Products/P001-2
It has Alexmos V.3 in it and after some intensive tunning I have it running quite good, the only problema I m having is with te ROLL axis, in quick Sharp moves it holds good but in a prolonged side move t will start to drift,first to on side the to the other..Any Ideas??
gtranquilla
RadioActive
Did you go thru the rigorous 6 point accel and gyro calibration for both IMUs, i.e., mounting each IMU on a cube and calibrating on each of the six planes?
smartaerials
Member
Yes..but Im about to go all through the proces again, I mean it seams all good till that horizon starts drifting, when it seams to hold beter the some vibrations come through to the camera..
Im using 3S,GH4, GMB 5208-150T
Im using 3S,GH4, GMB 5208-150T
gtranquilla
RadioActive
What are the inclination angles on your motors? See image here.... Inclination can help the FC yaw control become more effective at maintaining a fixed MR forward flight heading.View attachment 21092
Attachments
I must be missing something then, i have done everything step by step from the manual and youtube videos...
gtranquilla
RadioActive
Assuming your camera/BGC system is suspended such that the landing gear is independent you just have to hold your camera straight inline with MR heading when you power it up.
That works for heading mode...... more complex with using follow mode which was never really developed for Multirotor use anyway.
If your camera/BGC/landing gear all rotate together, you have to have your MR suspended in a sling so that the assembly under the airframe can rotate freely.
PID loop tuning of yaw axis has to be done for the Camera/BGC/landing gear angular momentum (not for the upper airframe angular momentum). The yaw motor can't handle that.
That works for heading mode...... more complex with using follow mode which was never really developed for Multirotor use anyway.
If your camera/BGC/landing gear all rotate together, you have to have your MR suspended in a sling so that the assembly under the airframe can rotate freely.
PID loop tuning of yaw axis has to be done for the Camera/BGC/landing gear angular momentum (not for the upper airframe angular momentum). The yaw motor can't handle that.
I have it on the S900 right now. So the yaw axis is mounted to the S900 bracket. Landing gear are independant.
After changing my i2c wire to a fancy separately shielded and braided wire, I thought I would get rid of my i2c/alexmos nightmare. But no... whenever i turn on my gimbal motors and move them around, I get something like 2 i2c erros for every 10 seconds. This usually ends up in the pitch accelerometer value going nuts (suddenly it points downwards all the time, regards of the actual position)....
With the motors off, I don't get any errors (or at least extremely few, like 1 every 10-15 mins)
I really need some help with this, as I am about to throw all this in the sea in frustration over having spent so many weeks on this.
Here's what I have tried so far (with no luck):
- Tried 2 different IMU's
- Tried different i2c cables, 1 std that came with the Alexmos 32 bit from viacopter, and then a shielded cable with ground running separately around vcc, scl and sca.
- Setting motor power to 0 on each motor, to see if I could see a system in which would make more i2c errors. No system was found.
- Moving the i2c cable away from any motors. It seems to be the same regardless of proximity to a given motor.
The board and imu is bought from Viacopter, and have been having these problems all along. The latest firmware, 2.43b5 didn't change anything as expected.
Help!
With the motors off, I don't get any errors (or at least extremely few, like 1 every 10-15 mins)
I really need some help with this, as I am about to throw all this in the sea in frustration over having spent so many weeks on this.
Here's what I have tried so far (with no luck):
- Tried 2 different IMU's
- Tried different i2c cables, 1 std that came with the Alexmos 32 bit from viacopter, and then a shielded cable with ground running separately around vcc, scl and sca.
- Setting motor power to 0 on each motor, to see if I could see a system in which would make more i2c errors. No system was found.
- Moving the i2c cable away from any motors. It seems to be the same regardless of proximity to a given motor.
The board and imu is bought from Viacopter, and have been having these problems all along. The latest firmware, 2.43b5 didn't change anything as expected.
Help!
dazzab
Member
I went through similar frustrations with an AlexMos32 I bought from GotHeliRC. The first thing I did was to operate it without the frame IMU and just the camera IMU. When I did that all the i2c errors stopped so I knew it had something to do with the second IMU.
I tried shielding the cable, wrapping it around rings etc to no avail. The second IMU was actually plugged in to a separate connector on the board which I thought was odd. I've only seen the second IMU connected in parallel to the first one. Sure enough the vendor told me they had a fix for the issue and that they would send me one. It arrived and it was a simple board that both IMUs connected to and then it connected to the board. So it just connected the two sensor in parallel as I've seen before. Believe it or not, that totally cleared up the errors. However, I'm still running with just one IMU for the time being and it's working great. YMMV.
Sadly I don't run with the second (yet) because I wanted to take that out of the equation before anything else. Will try the ferrite rings when some time decides to show up
gtranquilla
RadioActive
That is a typical error message when the pole count is set incorrectly...... based on my personal experience.