+Lee Cook Thanks for your reply! Yes, I'm using a photo interruptor sensor, which detects when a hole passes. Main problem now is that the inertia of the geared motor makes the tape move too far, which reduces accuracy.
+kloppertje But is that really a problem if the part is in a repeatable position for the pick? The only issue I thought of were those tapes where the parts were not in a integer mapping and would be presented at a different position each time even though the steps remained the same.
+Lee Cook I guess I won't be using that kind of tapes then ;). And inertia apparently is a problem, for example if one tape has more friction than the other. I'm doing some tests right now with a stepper motor, I'll upload a video later.
But then you'll have the problem of the number of steps changing as the spool diameter increases with more layers of the cover. You'll need to refactor steps/movement using the sensor as feedback.
+Lee Cook That's completely true. Control is partially feedforward (move appr. the number of steps used in the previous cycle), and partially feedback (move until sensor doesn't see a hole anymore). New video has just been uploaded btw.
Are you using the holes in the tape aligned with sensors to determine the final position?
I'm impressed with the amount of precision you're getting.
+Lee Cook Thanks for your reply! Yes, I'm using a photo interruptor sensor, which detects when a hole passes. Main problem now is that the inertia of the geared motor makes the tape move too far, which reduces accuracy.
+kloppertje But is that really a problem if the part is in a repeatable position for the pick? The only issue I thought of were those tapes where the parts were not in a integer mapping and would be presented at a different position each time even though the steps remained the same.
+Lee Cook I guess I won't be using that kind of tapes then ;). And inertia apparently is a problem, for example if one tape has more friction than the other. I'm doing some tests right now with a stepper motor, I'll upload a video later.
But then you'll have the problem of the number of steps changing as the spool diameter increases with more layers of the cover. You'll need to refactor steps/movement using the sensor as feedback.
+Lee Cook That's completely true. Control is partially feedforward (move appr. the number of steps used in the previous cycle), and partially feedback (move until sensor doesn't see a hole anymore). New video has just been uploaded btw.