How do I calculate acceleration of a tube at the uncoiler reel?

[Pieter-Jan De Loore]

Hello,
I'm making a tube uncoiler and I'm trying to find the acceleration of the tube at the reel (a3) can someone help me with this.

kind regards,
P-J

 

[Nidum]

Not immediately obvious why there would be any acceleration with the uncoiler running steady state .

You'll have to explain a bit more about how this uncoiler works so that we can understand more clearly what your problem is .

 

[Pieter-Jan De Loore]

Not immediately obvious why there would be any acceleration with the uncoiler running steady state .

You'll have to explain a bit more about how this uncoiler works so that we can understand more clearly what your problem is .

Hello Nidum,

Thank you for your response. Sorry for the bad explenation.

This uncoiler is not a steady state process. The uncoiler stands still and gets accelerated for a certain time because of F1 pulling the tube.
During this period, the dancerrol will move with acc. a2.
I'm trying to figure out what the acceleration of the reel is during the acceleration of the uncoiling process.
I hope this helps?

 

[Nidum]

OK . It is an intermittent process . I've seen similar equipment in use .

There must be something that stops the reel from just spinning freely . Is this the reel inertia and natural friction or is there some positive retarding mechanism such as a friction brake or a brake motor ?

 

[Pieter-Jan De Loore]

OK . It is an intermittent process . I've seen similar equipment in use .

There must be something that stops the reel from just spinning freely . Is this the reel inertia and natural friction or is there some positive retarding mechanism such as a friction brake or a brake motor ?

yes I use a pneumatic brake, but during the acceleration time I don't use the brake. The force F1 is to accelerate the the inertia (reel+(dancerrol)?). You can assume there is no friction.

 

[Pieter-Jan De Loore]

Is it correct to say that a1=a3+a2?

 

[Pieter-Jan De Loore]

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