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View Full Version : VE Cogging ? VIDEO


Blf
2016.03.27, 07:27 AM
Hey guys --- just pieced together (with a new VE board) a 94mm chassis for my TRP body and its running great other than at the lightest/beginning touch of the throttle, especially backwards in this vid, I get this cogging that I can sometimes hold --- if you just normally use throttle it will break right thru the cogging but NON of my others do it this bad. Is that the board or motor or maybe pinion? Does not happen unless the car is on track and under load --- no cogging when you hold in the air.

https://youtu.be/j-QE4y7B7CE

KWT
2016.03.27, 08:19 AM
Cogging at the start happens because the Mini-z brushless motors are not sensored. The controller has no way to tell how fast the motor is spinning. You can tun out most of the cogging if you use the ICS programmer on the VE board.

Blf
2016.03.27, 12:44 PM
Cogging at the start happens because the Mini-z brushless motors are not sensored. The controller has no way to tell how fast the motor is spinning. You can tun out most of the cogging if you use the ICS programmer on the VE board.

awesome --- have that, what settings should I be using on the ICS for the MR 03 VE to eliminate that cogging ---- my others are smooth in comparison (not that they don't do it at all but MUCH smoother)

KWT
2016.03.27, 01:38 PM
Check out this thread for some descriptions: http://mini-zracer.com/forums/showthread.php?t=39341

I would start with the motor time constant first.

Blf
2016.03.27, 03:46 PM
Don't see how that (or any of the other settings) would help

Why do my other ve's seem more smooth without messing with its settings ?

KWT
2016.03.27, 06:27 PM
The true "cogging" effect, which is a result of the startup ramp, is actually an oscillation caused by the ESC progesssively pulsing ALL the winding coils with a progessively increasing voltage, which causes the rocking back and forth as it tries to lock into the rotor and where it is, this has to be increased progresssively until the ESC has registered enough data to control the motor hence the visually noticeable effect.

In other words, the brushless motors in the mini-z all cog. Some more than others.

Blf
2016.03.28, 12:22 AM
Awesome info - makes sense as it is the same with my 1/10 setups (sensored vs sensorless)

Guess there is no need / market for sensored mini z motor setups?