Using UltraBorg as a BLDC motors driver through PWM

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Does someone already used an UltraBorg to drive brushless motors which have inside a PWM board driver?

thinking to use it for a Nichibo BLDC3229 or even later for same kind more powerful 42mm BLDC motors

Cherry on the cake, is it possible to use the digital pins of the UltraBorg for getting the signal feedback output of the encoders and set a PID for regulation of effective RPM speed?

Could all that been fully processed inside the UltraBorg bord with an adequate coding inside the UltraBorg, instead of implementing in Raspberry for better efficiency and reduced usage of I2C and Raspberry CPU?

Thank you for feedback!!!

piborg's picture

It might be possible to drive a BLDC motor with built-in drive board, it depends on how it handles the PWM input. The servo signal / PWM outputs are at a fairly low frequency compared to many devices, this may or may not be a problem. The PWM signal is a 5V logic level, so the built-in drive board would need to support that as well.

The standard scripts are able to bypass the standard limiting logic and directly set the PWM output using the CalibrateServoPositionX calls. The values range from 0 for 0% to 65535 for 100%:

CalibrateServoPosition1(0)       # Output 1 - 0% duty (off)
CalibrateServoPosition2(6554)    # Output 2 - 10% duty
CalibrateServoPosition3(32768)   # Output 3 - 50% duty
CalibrateServoPosition4(65535)   # Output 4 - 100% duty (fully on)

The second and third parts are much more tricky. Some of the pins for the ultrasonic inputs could be re-purposed to read encoder feedback, but it would require significant changes to the UltraBorg's on-board logic to do this and the ultrasonic capability would also be lost.

Any changes to the UltraBorg on-board logic would require re-programming the PIC, which needs a programming device and a fair amount of knowledge of how the chip itself works. This is not an easy task if you have not worked with PICs before.

Put simply I think there is a good chance that the board is physically capable of doing what you need, but the feedback and control parts are a fairly difficult software project on their own.

Disclaimer: These are my personal thoughts on the idea, UltraBorg was not designed with this type of use in mind.

And thank you for your answer!!!

piborg's picture

We are not currently working on a BLDC board.

Unfortunately we have had to scale back our plans recently due to the pandemic. A board for BLDC control is something we would like to do, but it is unlikely we will get around to it anytime soon :(

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