Plea for gimbal tuning wisdom....

[kloner]

figure out what axis is vibrating and try lowering i, raising d.... usually the nervous axis is to high of motor power if the i and d are not affecting taking the shake out

Shake i'm reffering to iso is from the vibrations out of your motors and prop..... that's why you gotta fly it to adjust it.

that small of motors/camera should do 3s, but if you find having to open up the motor power past 175 you might bump up the volts to 4s.... if you find yourself down around 50 try dropping the voltage

 

[Motopreserve]

Thanks kloner. I'm right in the middle at about 100+ - so I'll try upping it a tad. See how that treats me.

Ill hold old off any serious moves for the flight ready mount on the frame and actual in-air testing.

Here we go!

figure out what axis is vibrating and try lowering i, raising d.... usually the nervous axis is to high of motor power if the i and d are not affecting taking the shake out

Shake i'm reffering to iso is from the vibrations out of your motors and prop..... that's why you gotta fly it to adjust it.

that small of motors/camera should do 3s, but if you find having to open up the motor power past 175 you might bump up the volts to 4s.... if you find yourself down around 50 try dropping the voltage

 

[kloner]

you've probably seen this, but these are the videos i make to tune alexmos gimbals,,,, i split the screen in half, add post stab so i can compare what the view i'm looking at is doing, the i take that and duplicate it, zoom in 400-500% and crop that,,,, it shows exactly what you got. but you gotta get close and have a sound mechanical system to get that far.

 

[SamaraMedia]

Interesting process Kloner. I think I remember you mentioning you use Adobe Premier for editing and post stabilize in that program as well, that looks great. I've got a four year old MacBook Pro running Final Cut Studio 7 with Motion but get nowhere near as good a result as you're getting. I may not know exactly what I'm doing in post stab but my question is this, I'm thinking of upgrading my laptop to handle video processing quicker and also tinkering with switching over to Premier because I do not want to use Final Cut Pro X and I don't think my Studio 7 will work on the latest OS from Mac. How much of a learning curve is it to switch over to Premier? Not that that alone will improve my video production.

John

 

[Motopreserve]

Jwoike:

I'm like you, still on FCP7. I know it well and changing to X doesn't really appeal to me at this point. The Shake program in FCP doesn't seem to be on par with what they've gotten out of the AE stab. Or I just haven't spent enough time with it. I may try messing around with AE and see what I can do, and how fast I can get it done. I know clips could be stab'd in AE and then imported back to FCP - which might be the best of both worlds for me.

Wish I didn't have such a hard time blending ease of use, comfort and quality

Kloner: thanks for the vid. I have seen that and it's a great system. I fear I'm a ways off from that stage though....

 

[kloner]

once you understand what your trying to get done, the net has a youtube for that..... for me coming from a $49 video program to a 2014 mac book pro with premier cc was super easy. It has the big i7 processor, 2 gig nvidia card, 1 tb solid state and this thing blasts through everything except 4k post stab...... that just takes some time.

soner or later you'll hit a level where what your changing in pid doesn't show whats going on,,,, that's the best way i've found to do it,,, helps to start with 4k footy, so when you blow it up you can see it. i'm sure you can do something like it in FC.....

 

[SamaraMedia]

Thanks Kloner, just watched this tutorial on Vimeo - https://vimeo.com/71528383

Makes it all seem so easy.

 

[kloner]

yea, like that.

in my video above it was showing an agitated roll pid....

 

[Motopreserve]

I have one of the older style basecam blue 8 bit boards. Anyone know if this thing can accept Bluetooth connection?

I do not see the typical FTDI style connections (GND, +5, TX, RX, DTR). I do have an open set of +, GND TX and RX though - right next to the RC inputs. Would those be the bluetooth hook up?

 

[Motopreserve]

Here's a new one for you gimbal gurus....

since I wasn't frustrated enough with just the 2-axis setup, I decided to add a 3rd axis to up the ante

i actually have it working fairly well except now I get an almost imperceptible drift to the left on the yaw axis. I mean SLOW. I have to sit a state at it for a while to see it moving. I have the yaw motor wires routed away from IMU wires, and I have ferrite rings all over the place.

Any ideas?

 

[Bartman]

is this when the helicopter is sitting on the bench?

 

[Scott Drysdale]

It is a gyro issue on the yaw axis which needs to be recalibrated. Also much will depend on the yaw axis IMU placement, i.e., above or below the yaw motor.

Personally I believe the real source of the problem is the limitation of the simple IMU sensors used on the BaseCAM and Martinez BGCs. These sensors do not incorporate more advanced features needed to auto-correct for Yaw drift over time.
The s.bus connection on the Basecam 32 bit 3 axis units opens the door for additional future improvements by means of tapping in to the DJI FC gimbal control but also hopefully, in the near future, the FC IMU which is much more sophisticated, i.e., includes magnetometers etc. There is a major difference between 6DOF and 9 or 12 DOF IMUs.

BTW - Have you gone thru the advanced procedures for calibrating each IMU? There is a Youtube video showing how to do this with the IMU mounted on to an empty T-Motor storage box...... it might help but not totally.

Here's a new one for you gimbal gurus....

since I wasn't frustrated enough with just the 2-axis setup, I decided to add a 3rd axis to up the ante

i actually have it working fairly well except now I get an almost imperceptible drift to the left on the yaw axis. I mean SLOW. I have to sit a state at it for a while to see it moving. I have the yaw motor wires routed away from IMU wires, and I have ferrite rings all over the place.

Any ideas?

 

[Motopreserve]

Thanks for the quick response guys...

BART: I am doing this testing/tuning (anxiously awaiting the Phobotic!) on the bench. The gimbal/quick release is secured to a simple PVC stand that I built for tuning.

SCOTT: I do not have an additional IMU, it's just the one used in 2-axis setup. The unit I have is an 8-bit version with the expansion board connected. I looked high and low for connection help - and based on the one connection diagram I found that looked like my particular board version, it had me only connect the expansion board to the main board via GND, VCC, SDA and SCL. Another connection diagram I saw looked to tie the expansion board and the IMU together for connection on the main board - bt that diagram did not show a dedicated header for the Yaw like mine has.

I did do the more advance 6-point cal when it was still 2-axis. But i read enough about it being worst if not done absolutely perfect that I stuck with the single cal - which was done using a spirit level.

Am I completely off base here, or is this the correct way to set up for this expansion board??? The connection diagram I used is shown below.



Thanks folks.

 

[Bartman]

what does it do if you bring it out into a field away from your home's electrical and magnetic interference?

 

[Motopreserve]

what does it do if you bring it out into a field away from your home's electrical and magnetic interference?

Aha. Very good question. I have NO idea Just got the thing hooked up. I'll give it a shot outdoors handheld and see how it makes out.

 

[kloner]

go into the rc control tab and hit auto sub trim..... if it still drifts manualy change that number till it stops.

 

[Motopreserve]

go into the rc control tab and hit auto sub trim..... if it still drifts manualy change that number till it stops.

Thanks Kloner.

I don't have any RC inputs hooked up yet - but since I'm getting close to planting a small depth charge on this 3rd axis expansion board, I tried it anyway. No change. Still creeping to the left. Trying it outside away from all electronics didn't help either.

What's really awesome is that any motor power at all to the Yaw motor causes the pitch axis to shake with violent low oscillations and any angle off level. So that always helps

 

[kloner]

it sounds like the fake compass, and acceleromoters/gyros are not calibrated right. and you gotta calibrate each mode you want to use to keep it consistent.... i usually pin the camera tray down to a pillow with a bubble on the tray and i get it so it can't move...... i hit calibrate gyro, then calibrate compass, then switch profiles, hit calibrate gyro, calibrate imu, switch profiles, repeat. if there is any movement between cali gyro and imu it will drift

 

[Motopreserve]

Sorry Kloner, you lost me here. I only have calibrations for gyro and ACC, and it only in the main basic window. Is there another calibration I'm supposed to be doing for the 3rd axis??? Aren't these calibrations all for the IMU?

i guess I don't know the differences that you describe here:

if there is any movement between cali gyro and imu it will drift

 

[kloner]

no, thats the calibrations, gotta do both calibrations on each profile without any movement... pin the thing down so when it powers up it can't shift between all the calibrations.... and make it super level