Arduino with multiple motors

Hallo everyone,

for a project of mine i have to control multiple motors with an Arduino/Arduino Mega (no Servo Motors, standard DC-Motors or Gearboxes) ... to be precise i want to control 20 motors. at the moment it's moste likely that i will be using 6v motors.
at the end it's possible that i will be using less than 20 motors, but for now the goal is to be able to control 20 motors.

i want to control every motor seperately... their job is to wind and unwind a band. every motor has some kind of cable roll mounted and with this cable roll the motor winds and unwinds the band

now my question: does anyone have experience in controlling that many motors with an Arduino or Arduino Mega... is that possible? at the moment i'm testing with this motor-driver:

what's good about this motor driver: seperate circuits for motor supply and motor control ... the arduino alone won't be able to supply that much current. but as you know that motor driver only has 2 channels and i haven't found a motor-driver for a larger number of motors yet. would it be possible to clone the circuit of the 2-channel motor-driver and upscale that whole thing (i hope that's understandable) so that i can control 20 motors?

another question is.. is it possible to get rotation data from the motors? it would be perfect if i could tell how much every band of every motor is unwinded. that would make the calculation of the movement much easier. are there motors that can do that? or do i have to build some kind of light-barrier construction to see how much every cable-roll is unwinded?

sorry for my bad english.. i hope its understandable and i hope you can help me :slight_smile:

would it be possible to clone the circuit of the 2-channel motor-driver and upscale that whole thing

Yes you just keep on reproducing the basic circuit.

it would be perfect if i could tell how much every band of every motor is unwinded.

In that case you need to use a stepping motor, these need pulses to drive them.
http://www.thebox.myzen.co.uk/Workshop/Motors_1.html