# Animating wire/cable/rope wrapping around a cylinder

I have searched everywhere on the web for a way to do this, but I can’t find anything. Someone have any ideas for doing this without using physical simulations? The operation should be this:

the red wire passes through the blue object (which is static) and is anchored to the yellow object, which can rotate When the yellow object rotates, the wire wraps around the cylinder in a similar way to a fishing rod.

• Well, as Duarte has closed the answers, I'll answer on the page he has linked ;) Jun 18 '20 at 18:02
• I don't think this is a duplicate question. As the animation progresses, the windings need to come closer, which is not the case in the previous question. Jun 18 '20 at 18:35
• Reopened. @moonboots feel free to post your answer here if you like Jun 18 '20 at 23:22
• oh ok thanks ;) Jun 19 '20 at 1:20

This is a somewhat similar answer to @moonboots', perhaps expressed in a different way.

1. Using the shipped add-on Add Curve: Extra Objects, create an Archimedean Spiral.
2. Create your rope as a straight subdivided cylinder of some kind: it could be an array of segments, or simply another curve. Mine is long along X.
3. Use a Curve modifier to deform your rope along the spiral.
4. As you move the rope along its deforming axis (my X), it will wind itself around the spiral, and, when it runs out of curve, project itself from the end in the direction of the spiral's last segment. With (T)interpolation set to 'Linear' in the timeline, keyframe the rope's start and end positions, for a whole number of turns.
5. Now, the trick is to keep the fixed end of the rope stationary in the length-dimension of the spiral. Again, with interpolation set to 'Linear', keyframe the spiral's translation the other way, to compensate for the movement of the tail of the rope along it. Neither the spiral nor the rope rotate.
6. Create a spool that does rotate, inside the spiral; keyframe its rotation to sync with the rope's progress around the spiral. You know how many turns the rope has travelled between start and end frames; just keyframe that number of turns into the spool.

Here is a solution:

• Create 3 objects: The cylinder, the rope (a cylinder with an Array modifier and a Curve modifier) and the curve (used by the rope's Curve modifier).

• Rotate the cylinder with some keyframes (here -400°). Move up the curve, move down the rope (or increase its Array count) so that the rope seems to follow the cylinder rotation. Make sure that each of your animations interpolation is linear (in the Dope Sheet press T > Linear).