Vortex dynamic balancer


ChrisViperM

ChrisViperM

Active Member
Thanks a lot for sharing....best find in a looooong time. I've been looking for a dynamic balancer for ages, but all i found so for was mainly for industrial applications and lots of $$$$$. The procedure seems to be the hell of a pain in the butt, but on the other hand the time you invest will certainly pay off. This is 1000 times more accurate than the usual prop balancers and iPhon-App-Vibration trial and error method.

Will order one straight away before they are all "Sorry, no stock left"....

PS: Just placed the order....


Chris
 
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srbell

srbell

Member
Ok, got my Vortex! Now how to balance propellers? I can pretty much use the same mount you use for the ducted fans for my motors, buy what about the propellers? Any good stand designs out there that would work to balance the motor, then the prop? Most of my motor/propeller units are pulling from 2 to 3.5kg, that's a lot of force. Ideas?
 

dynexhobby

dynexhobby

Good vibrations
Hi Srbell,

For multirotors you don't really need a dedicated mount. The way I do it is to secure the multirotor to a bench. Insert a piece of foam between the bench and your platform. This will stop vibrations from refelecting back into the rig. Install the accelerometer sensor on the multirotor frame adjacent to the motor. You can then run through the 4-point method to balance the motor and then 2-blade method to balance the propeller. I have a video showing how to do this (see below),

http://www.youtube.com/watch?v=AjZ23L6aUQ4

You will need to download the software to record vibrations and perform the balance solution.

Here's the link,

http://www.dynexhobby.com/software.html

Enjoy

DH
 
Last edited by a moderator:

srbell

srbell

Member
That's pretty simple, thanks! How are you measuring you motor rpm's?


dynexhobby said:
Hi Srbell,

For multirotors you don't really need a dedicated mount. The way I do it is to secure the multirotor to a bench. Insert a piece of foam between the bench and your platform. This will stop vibrations from refelecting back into the rig. Install the accelerometer sensor on the multirotor frame adjacent to the motor. You can then run through the 4-point method to balance the motor and then 2-blade method to balance the propeller. I have a video showing how to do this (see below),

http://www.youtube.com/watch?v=AjZ23L6aUQ4

You will need to download the software to record vibrations and perform the balance solution.

Here's the link,

http://www.dynexhobby.com/software.html

Enjoy

DH
Click to expand...
 

dynexhobby

dynexhobby

Good vibrations
The Scope software will measure RPM from the main vibration signal. However, when I run the motor I used the PWM signal on the GWS Servo driver, that is 1150ms refers to say 40Hz on my ESC.
 

srbell

srbell

Member
So when I hook up the IR sensor I get the expected signal on channel 2 with a spike corresponding to the white line on the motor. But I also get a spike on channel 1 corresponding to the IR's sensor! They look almost identical. When I unplug the IR sensor's cable the spike on channel 1 goes away. Strange... Idea?

http://youtu.be/2SaCji4xi0c
 

dynexhobby

dynexhobby

Good vibrations
A few things can cause this,

1. A compound MIC port on your laptop. This combines MIC and headphones into a single port.
2. Using a MONO MIC port.
3. An audio mixing device. Some audio drivers allow for some mixing between channels. Check your audio driver and deselect any mixing.

for 1 and 2 you will need to find a stereo MIC port. Some people have succeeded using LINE IN as well but you need to boost the volume. If all else fails then purchase an iMic, it is a plug and play device and works off a spare USB port.

cheers

DH



srbell said:
So when I hook up the IR sensor I get the expected signal on channel 2 with a spike corresponding to the white line on the motor. But I also get a spike on channel 1 corresponding to the IR's sensor! They look almost identical. When I unplug the IR sensor's cable the spike on channel 1 goes away. Strange... Idea?

http://youtu.be/2SaCji4xi0c
Click to expand...
 

dynexhobby

dynexhobby

Good vibrations
Just another point, when balancing a multirotor, the IR sensor isn't normally required because you get away with using the 4 point or 2 blade propeller methods.
 


srbell

srbell

Member
I'm using the iMic... Maybe something's defective with the iMic, stereo cable or Vortex board where maybe I've got a short between the left and right channels. The only reason I was even using the IR was to determine the hz I'm running the motor. With just the accelerometer, the hz is all over the place. Obviously I'm getting harmonic noise so I'll go back and try to get a clean signal first and mess with the IR later.


dynexhobby said:
A few things can cause this,

1. A compound MIC port on your laptop. This combines MIC and headphones into a single port.
2. Using a MONO MIC port.
3. An audio mixing device. Some audio drivers allow for some mixing between channels. Check your audio driver and deselect any mixing.

for 1 and 2 you will need to find a stereo MIC port. Some people have succeeded using LINE IN as well but you need to boost the volume. If all else fails then purchase an iMic, it is a plug and play device and works off a spare USB port.

cheers

DH
Click to expand...
 

srbell

srbell

Member
Another question lol?

I don't seem to be getting a clean sine wave so I went to the frequency tab. My main frequency is around 3.5khz. That's crazy high! That's 210,000rpms! I don't think so. Is this maybe a problem with the motor. Most of you are balancing inrunner motor for DF units, but this is a 6135 Foxtech outrunner. This motor has extremely heavy cogging (detent). Is this motor not able to be balanced with the Vortex?

View attachment 16333
 

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dynexhobby

dynexhobby

Good vibrations
Hmmm.... considering that the Vortex is outputting the IR and Accelerometer signal means that the circuit is working as expected. I suspect that there may be audio mixing happening at the PC. Also check that the "Channel Mode" in the Scope is set to "Single" not "Ch1+Ch2". See image. View attachment 16338 View attachment 16339

srbell said:
I'm using the iMic... Maybe something's defective with the iMic, stereo cable or Vortex board where maybe I've got a short between the left and right channels. The only reason I was even using the IR was to determine the hz I'm running the motor. With just the accelerometer, the hz is all over the place. Obviously I'm getting harmonic noise so I'll go back and try to get a clean signal first and mess with the IR later.
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dynexhobby

dynexhobby

Good vibrations
I don't think thats your RPM :frog:

It sounds like your are getting electrical intereference from somewhere, maybe a nearby electrical source such as an ESC. You can try a few things here;

1. Isolate the electrical source (turn it off if possible except for ESC).
2. Use the filter capacitor on the accelerometer. Turn Vortex filtering to max.
3. Use the "Band pass" filter on the Scope software. See my tutorial on my YouTube channel.... http://www.youtube.com/watch?v=Onn0NhW7BOU

The Vortex should be able to balance no problem at all. I balanced a very large Scorpian motor on my RAMTEC EDF unit. That had high cogging and high switching noise as well. Just need to filter that stuff out first.

cheers

DH

srbell said:
I don't seem to be getting a clean sine wave so I went to the frequency tab. My main frequency is around 3.5khz. That's crazy high! That's 210,000rpms! I don't think so. Is this maybe a problem with the motor. Most of you are balancing inrunner motor for DF units, but this is a 6135 Foxtech outrunner. This motor has extremely heavy cogging (detent). Is this motor not able to be balanced with the Vortex?

View attachment 20311
Click to expand...
 

srbell

srbell

Member
I've got a few questions about 4 point balancing. First, when getting a balance solution I've been running into two issues. One will give me a negative angle. For example, .121g or weight at -112 degrees. I'm simply using a polar chart for strobe balancing with the motor diameter cut out to asset in the 0, 120 and 240 positions. The increase in degrees from 0 to 360 in a counter clockwise rotations... So if I get a negative solution, do I just measure out for the example the -112 degrees, 112 clockwise from zero? The other thing, even though I've got a sine wave after filtering my waveform it's fluctuating a fair bit. Should I just take the max value I see in the scope display at the top or try to average it out? The second issue I'm having is sometime the solution brings up a window stating there's too much vibration and to use a smaller weight... I get the weight down so small it's hard to even measure but I'll get the same dialog saying to go smaller lol! Any ideas on that?
 

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