Help with Adafruit and brushless motors

Hi everyone. I’ve got a very simple question: Can I use this Adafruit drv8833 motor driver to control two (2) dc brushless motors. I know it’s kind of a stupid question. Sorry and thanks in advance.

No, it will work for 2 DC brushed motors. Brushless motors are more complex to drive and normally need an ESC (Electronic Speed Control) and are controlled using the Servo library.

Steve

Just to clarify: that'd be a motor with built-in ESC. You won't be able to slap an ESC onto an existing brushless motor and expect it to work. Those motors are also known as "continuous rotation servo".

wvmarle: Just to clarify: that'd be a motor with built-in ESC. You won't be able to slap an ESC onto an existing brushless motor and expect it to work. Those motors are also known as "continuous rotation servo".

Clarify? You completely lost me. What would be a brushless motor with a built-in ESC? One that works with a DRV8833 or one that doesn't work?

And what does that have to do with a continuous rotation servo? They use brushed motors in every example I've met.

Steve

Very simple, you can not just slap a random ESC on a random brushless motor and hope it works, as it almost certainly won't. The two have to be integrated.

Of course when you have a motor with integrated ESC that responds to servo-type control signals it doesn't matter whether it's brushed or brushless. You send the control signal, motor moves at the speed you tell it to. The brushed/brushless part only becomes important in relation to what the motor has to do - e.g. waterproofing the motor is much easier when it's a brushless type.

wvmarle: Just to clarify: that'd be a motor with built-in ESC. You won't be able to slap an ESC onto an existing brushless motor and expect it to work. Those motors are also known as "continuous rotation servo".

Why? I use random pairs (ESC + BDLC) without any problems.

Cheers, Kari

How does that ESC get any feedback from the BLDC motor?

The ones that I have come with two wires: power and ground. Not much to control there beyond on and off. Never tried PWM on them, not likely they'll react well to it, but if it does the DRV8833 will do quite well - until you try to change direction, of course... then they'll simply stop working as you fry the control electronics of the motor.

Most hobby brushless (BLDC) motors are sensorless and have 3 wires. At any instant 2 wires are powered and the feedback comes from the 3rd wire (loosely speaking). Sensorless ESCs that work with these are extremely common and can be chosen separately from the BLDC. And they are driven by servo-type signals.

They will not work with a DRV8833 which was the question I thought I was answering.

Perhaps we should have asked exactly what sort of BLDC the OP is talking about. Just another case where if you don't give any useful detail in a question you may get a random assortment of answers, relevant or otherwise.

Steve