Lenght measuring system for film tape

Projects General Guidance
1

Hello all,
I'm currently working on a new project to measure the distance of a film tape supplied in a roll.
The main goal is to be able to measure the tape lenght of the roll, to check if it matches the purchased value, for example 50 meters.
I believe that an Arduino, an LCD and an encoder should be enough, but i've some doubts regarding the correct encoder.
The encoder must read in both ways because the tape may be pushed back, which means that in one direction it will count up, and on the opposite direction it will decrease the current value.
Can you please advise if is possible to create this project?
Is there any similar projects available?

Best regards
Jose Cruz

2

You could use a rotary encoder, or you could just weigh the spool.

3

cruzjos:
Can you please advise if is possible to create this project?
Is there any similar projects available?

Yes, very similar things have been done many times. Do a forum search for 'wire cutter'. Add 'arduino' and there are also a number of YT videos along the same line.

4

Rotary encoder attached to free running roller, so you don't have the problem of the speed changing with the thickness of the roll.

5

A rubber wheel and a mechanical counter?

I can imagine that measuring the weight of the tape or of the roll would also do the job.

If a screws scale is available on-site, maybe that one can be used to check the length of the tape as well.