Hi everyone!
It's very simple: low current motors may be controlled by Arduino. I've solved one problem and one has been remained. Arduino's pins voltage are fixed: you can just switch them on or off, not change. For three coils motors, (DVD Rom motors) there is just one problem: how to change the voltage of the pins in right time? or any othere idea?
Why not ESC? Because cheap (there are cheap for Wests not for us) ESCs aren't controlled by digital signals but analogue (PMW). It's not as precise as digital.
PWM is digital.
You have to produce 3 PWM signals shifted by 120° and of the desired frequency. Don't forget the drivers or you risk to kill your Arduino.
I guess there is a misleading. Sometimes you control the speed by rate of "HIGH"s sometimes by pulse width. The later produced by a digital process but is not as precise as the first.
However you told me that it's better to use a ESC and it could solve my problem?
BLDC motors are kind of stepper motors driven by 3 phase AC frequency, generated by the ESC. The ESC in turn can be controlled digitally (UART, SPI), analogue (voltage) or by PWM (duty cycle).
DIY BLDC motors have integrated sensors that tell the controller when to turn the voltage positive, negative or off. Disk motors instead shall rotate at the nominal disk drive speed, which is given by the AC frequency. They will work at different speed as well, provided that they are properly accelerated.
And for the sensorless BLDC motors used in RC planes-cars-boats the ESC is using the 3rd unpowered phase to let the analog comparator do a zero-cross sensing, so the MCU in the ESC knows the position of the motor.
1 Like
They make 3way mosfet motor drivers for this purpose. You vary the voltage by feeding the bridge with SPWM signals.
Another way to accomplish your goal would be with encoders on the motors
Can you post a schematic as you have it wired, not a frizzy picture. Include links to the "Technical" information on each of the hardware devices. I would suggest you buy a few more Arduinos if you have the motors directly connected to the Arduino as implied. The pins will be destroyed by the flyback current from the motors.
How much is too expensive? This esc would be perfect for driving a brushless motor, but I don't know exactly what you are doing with the Rom motors.
Hi,
Go to YouTube and in its search engine type, arduino esc motor control , and look at some examples that may help you.
Tom.... 
This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.