Hi! I was working on making a walker robot, got all of the parts built and put together, then stopped and realized that the arduino might have a hard time controlling 4 motors at once. Is there a special trick to doing this, or can it simply not be done?
The Arduino can control several motors or servos, but cannot provide power for any. Always use a separate motor/servo power supply and connect the grounds together.
Do you want just on and off, speed control in one direction or speed control with forward and reverse? What is the stall current of the motors? What is the rated voltage of the motors. Are they steppers, brushed or brushless? All of the details are important for choosing driver for the motors.