I am looking for a cheap Brushless Motor Position Controller

Hi! Can you please help me if you know any cheap web for buy a motor position controller?

I am working with an Arduino MEGA 2560 and 4 brushless motors with optical encoders, my problem is when the code is running for a long time the position error increases and I need a lot of precision, I think that it happens for a delay when the code is reading the position. So I need to know with more precision the position in each moment, I need 4 position controllers but all of them are very expensive for my budget.

I found these ones:
176.53€ http://www.roboteq.com/index.php/roboteq-products-and-services/brushless-dc-motor-controllers/sbl1360-detail
177.90€ http://www.robotshop.com/en/sbl1360-60v-1x30a-brushless-dc-motor-controller.html
192.20€ http://www.roboteq.com/index.php/roboteq-products-and-services/brushless-dc-motor-controllers/mbl1330n-298-detail
192.26€ http://www.roboteq.com/index.php/roboteq-products-and-services/brushless-dc-motor-controllers/mbl1330-detail
214.51€ http://www.electrokit.com/en/brushless-dcmotor-24v-25a-with-encoder.51451?currency=EUR

But I am looking for cheaper one. If someone knows other website I will thank you very much.

Hi, motor position controller, do you mean a servo type application.
What size are the motors and what are they moving?
A picture of your project and a copy of code and circuit diagram, CAD or picture of hand drawn circuit in jpg, png or pdf will help us help you.
Tom..... :slight_smile:

Sorry, I did not explain myself correctly. The 4 motors that I use for now are brushed motors. So I do not have any code or circuit diagrams for BLDC control, but I am looking for a BLDC controller that does position control, like a servo motor.

I am looking for BLDC motor controllers (motor power is 60W). And I want position control, not speed control.

I have looked for it in:



Do you know another web page for look for it?

The servo feedback loop can be done on the Arduino, so a PWM driven 3-phase driver would be needed. Might need 4 Arduinos though

Hi, the motors that you are using are they geared to the encoders, I cannot see how a brushed or BLDC can be position controlled unless you have a gear box and have the encoder on the output of the gearbox.
Can you post a picture of your project as it is at the moment.
Please see my previous post.

A simple optical single channel will not give you position info, only speed, you need a digital position encoder to feed back position to keep them in sync.

Tom.... :slight_smile:

The servo feedback loop can be done on the Arduino, so a PWM driven 3-phase driver would be needed. Might need 4 Arduinos though

Wouldn't one of the many "hobbyist" ESCs work for that application? That way at least the 3-phase (velocity) is handled for you. They probably don't close a "velocity loop" in those either.

Since the OP did not tell us the encoder resolution nor the RPMs it's tough to guess whether the "Mega" will have enough horsepower to do four position loops.

I would hope the OP is using interrupts to read the encoders and unless the 4x resolution is needed, counting just one transition instead of four helps too.

Could always switch over to a DUE.