## Friday, March 15, 2013

### Curvy Copter with Jumbling

The Curvy Copter is a twisty puzzle which is a cube when solved, but which can shapeshift when scrambled and jumbled. This tutorial will involve jumbling, which is a complex theoretical topic. Its effects are fairly straightforward on this puzzle though. To buy this puzzle, click here.

The Basic Plot

2. Solve Bottom Half
3. Solve Top Half

A normal scramble of this cube involves turning the edges 180°. If, however, we turn an edge part way, we can jumble this puzzle. This essentially means that a center piece will change its orbit. This is clearly explained in the video.

To return the puzzle to cube shape, we need to isolate two corners which are "sticking out" and apply a jumbling type move to put both of them back. As is often the case, this is far far easier to see in action than to explain. The video  below will help return your cube to its correct shape.

Step 2: Solve Bottom Half

To begin with, solve the white face edges and centers. (Any colour face will do but I prefer to start with white.) The edges cannot move, but only rotate in position. Therefore, move the white centers by turning adjacent edges, until they are positioned next to the white edge.

Since the cube was jumbled, it's almost certain that some of the white centers will not be in their correct orbits. To fix this, swap the white center with any other unused center, by using the jumbling move. Then turn it into its position.

Once the white face is solved (apart from corners), turn the cube so that the white face is on the bottom.

Now, for each of the four middle edges,
• Ensure the middle edge is "upside-down" or "backwards".
• Place the desired corner by turning it around the top face until the white is facing upwards.
• Move each of the correct colour centers into place by turning edges.
• If a center is not in its correct orbit, transfer it into its orbit via the jumbling move.
This video will show how simple this all is.

Step 3: Solve Top Half

At this point, turn the yellow (top face) edges into place. Look for any middle face centers which can be placed using any convenient 3-cycle, for example FRFR.

Almost certainly, some centers will not be able to be cycled home simply. This is due to the jumbling. The goal from here is to unjumble these centers one by one until all are placed.

The only potentially tricky situation is where you are left with a yellow center and a non-yellow center needing to swap places. This can be accomplished by swapping two other yellow centers via the jumbling move. This essentially creates a 3-cycle with the two centers needing to be swapped.

Once all centers are placed, it's time to deal with the yellow corners.

To place corners, use the cycle LBRF R FRBL R (or its mirror). This moves 3 corners around the top face.

To orient corners, use the cycle (LBRF)x6 or its mirror.

Again, all will be made clear in the following video.

And that's it. Your Curvy Copter is now solved. I trust this site has been helpful. If you have any questions or want some clarifications, please use the comments to do so. To buy this puzzle, click here.

1. I'm impressed with the way you have created variations on the corner piece series that work on so many different types of puzzles. Did you know that a Corner Piece Series can also be used to solve the corners on the last layer of the curvy copter?

I discovered this move that seems like the closest analog of a CPS for the copter: (BLBR BLBR)

Here the back edge plays the role of the top face in the original CPS. On this puzzle, we can only use 180 degree twists, and each is its own inverse. So the CPS simplifies slightly here. But it does almost the same thing as on the 3x3. The CPS moves only the corners. It fixes the BL corner, and cycles the other three corners on the top face.

You can also combine this CPS with its mirror to reorient two of the corners:
1) Do a CPS: (BLBR BLBR) to move three corners out of position.
2) Rotate the cube 90 degrees clockwise (seen from above).
3) Do a mirrored CPS: (BRBL BRBL) to bring them back into position, but with different orientations than before.

1. Hi chruska

Thanks for your comment. Yes I knew CPS would work. If you look on the helicopter cube page, you'll see that step 3 is "alternative: solve corners using CPS". I decided not to do that for this puzzle. From memory, my CPS was (FRFL)x2. I think i also knew about the orientation, but I can't remember if I used that in the helicopter video. In the end, I felt that the CPS was not well enough known to use as the main method in that (or this) solve. I think it's the coolest sequence in existence.

2. I thought you must have discovered this type of CPS at some point, since it's very much in the spirit of the Ultimate Solution. But I didn't notice you already used the CPS on the helicopter cube page.

The (LBRF)x6 move is also a very cool sequence.

Thanks for putting so much effort into this site. I like the way you solve puzzles using only a very small number of algorithms that are nearly the same on lots of puzzles.

2. i have a parity problem, everything is fine but two corners are in the place that corresponds to the other, did you know an algoritm to solve this case?

3. i have that same problem and i cant find anything
on it

4. Most likely what happened was 2 of the same color center (yellow and yellow) got swapped. I think you can fix this using the jumbling swap and them resolving the top. (Make sure you swap the 2 same color centers)

5. need to twist one corner. have tried several combos using the other corners and can't seem to work it out. suggestions? thanks!