I am creating follow focus system (motor with gears that moves camera lens ring). I think the best choice is BLDC motor (DC geared are too loud, stepper don't have enough torque or too big).
I need a motor to rotate at ~100RPM. The torque needs to be at least 1kgcm. I found some bldc motors that satisfy my needs (like emax 66KV + magnetic encoder for feedback) - most of them are used in gimbal systems.
Now onto the controller. It needs to be small - not bigger than 4cm in any direction. I believe 10W is more than enough. I'd like to be able to power it with 5V - directly from power bank - there is no need for more voltage since it is low RPM low torque project. I did some research and couldn't find any drivers that satisfy those requirements. They are either too big or require at least 7.2V to be powered (RC escs).
I therefore think the only way is to create my own controller. I based it off of this solution (https://simple-circuit.com/arduino-sensorless-bldc-motor-controller-esc/).
My questions are:
- Since I am using 5V to power motor and arduino also outputs 5V from its pins can I skip IR2104S gate drivers? 4.3V should be enough motor voltage.
- 6 mosfets bridge take up a lot of space. Is there an IC that provide same functionality? As stated before the motor should only need about 10W.
- If you notice any mistakes in my plan or explantions let me know