Prop / Motor balancing with ACC ?

[Plüschi]

Tired of the "try add some weight there" method in prop / motor balancing i realized i need better data to balance the stuff. The 80ms interval of MSP_RAW_IMU gives us 12 values/sec, 720 values/min, or about 300 RPM max. I need much faster data. One value every 4ms gives max 6000 RPM, which sounds reasonable.

The ACC data X and Y should move along a circle representing the motor vibration. I need a simple way of knowing the actual angle of the motor to make predictions where and how much weight to add. One way would be to use a laser rpm meter sensor, or a magnetic pickup. Any other ideas?

[EOSBandi]

Tired of the "try add some weight there" method in prop / motor balancing i realized i need better data to balance the stuff. The 80ms interval of MSP_RAW_IMU gives us 12 values/sec, 720 values/min, or about 300 RPM max. I need much faster data. One value every 4ms gives max 6000 RPM, which sounds reasonable.

The ACC data X and Y should move along a circle representing the motor vibration. I need a simple way of knowing the actual angle of the motor to make predictions where and how much weight to add. One way would be to use a laser rpm meter sensor, or a magnetic pickup. Any other ideas?

Check this : http://diydrones.com/forum/topics/balan ... and-motors

[Plüschi]

Thanks. Thats exactly what i need. Unluckily the guy doesent share the sources which makes it unusable.

[howardhb]

All sources ARE published!

look for dyn_prop_balance_publish.zip on this page:http://diydrones.com/forum/topics/balancing-propellors-and-motors?id=705844%3ATopic%3A1011737&page=5#comments

[Plüschi]

Thank You !

I had not found it before. Unluckily he supports only this adxl sensor and also its VB or similar.
I try take his ideas and make a multiwii sensors / processing compatible version.

This is how my Turnigy D2836 / 750kv no prop looks like, ACC readout at 200hz