Online since 2002. Over 3300 puzzles, 2600 worldwide members, and 270,000 messages.

TwistyPuzzles.com Forum
 It is currently Sat Apr 19, 2014 12:51 am

 All times are UTC - 5 hours

 Page 1 of 1 [ 17 posts ]
 Print view Previous topic | Next topic
Author Message
 Post subject: Fudging and jumbling Dayan's Gem IIPosted: Sat Apr 16, 2011 9:46 am

Joined: Mon Feb 02, 2009 3:50 pm
Last Thursday, Dayan’s Gem 2 arrived. I had great fun solving it. In the end I needed to add two alg’s to my gem-1 repertoire (a 3-cycle for the pieces with pentagonal faces, and a 3-cycle for the rectangular centre pieces). When scrambling I accidently made a fudging move like on the 1st photo. I didn’t pay much attention, continued scrambling, solved the puzzle and ended in the jumbled situation of the 2nd picture. I fudged back and was able to solve it using only ‘legal’ moves.

My intuitions tells me the 2nd picture isn’t possible without fudging. Can anyone prove that?

_________________
view my collection at http://picasaweb.google.co.uk/maarten1729

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Sat Apr 16, 2011 1:15 pm

Joined: Thu Sep 24, 2009 12:21 pm
Location: Chichester, England
That isn't fudging. Fudging is a technique used to remove jumbling via the making of space where there would be an infinite number of pieces.

_________________
3x3x3 single: 5.73 seconds.
3x3x3 average of five: 8.92 seconds.
3x3x3 average of twelve: 9.77 seconds.

Buy the Curvy Copter Skewb, NovaMinx, and more here!

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Sat Apr 16, 2011 11:49 pm

Joined: Mon Feb 02, 2009 3:50 pm
The definitions I found on the forum are not conclusive: does it include making otherwise illegal moves or is it restricted to pieces being in illegal places. If anyone can clarify, please do (in a dictionary thread).

Enough semantics: can somebody explain if the shape with the ears is possible with only legal moves? (with the color scheme shown that is!)

_________________
view my collection at http://picasaweb.google.co.uk/maarten1729

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Sun Apr 17, 2011 2:38 am

Joined: Thu Sep 24, 2009 12:21 pm
Location: Chichester, England
Yes, but this puzzle isn't fudged. It jumbles. And fudging is in the building process of the puzzle; "I fudged the puzzle to allow so and so pieces to move".

_________________
3x3x3 single: 5.73 seconds.
3x3x3 average of five: 8.92 seconds.
3x3x3 average of twelve: 9.77 seconds.

Buy the Curvy Copter Skewb, NovaMinx, and more here!

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Sat Apr 30, 2011 3:27 pm

Joined: Sun Mar 15, 2009 12:00 am
The case shown is possible without the illegal potentially puzzle-damaging move. I have encountered it on my Dayan Gem II adventures.

_________________
WCA

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Sun May 01, 2011 5:45 am

Joined: Thu Sep 17, 2009 6:07 am
Location: Germany, Bavaria
Emile wrote:
The case shown is possible without the illegal potentially puzzle-damaging move. I have encountered it on my Dayan Gem II adventures.
If you define "legal moves" as 180 degree turn of the edges, only (you could call them Helicopter moves), the shown situation is certainly not poosible. 180 degree edge turns will never change the shape of the Gem II and the shown situation is shapeshifted.
Any other moves of edges can only be jumbling moves. Or how do you define "legal"?

_________________
My collection at: http://sites.google.com/site/twistykon/home

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Sun May 01, 2011 6:54 am

Joined: Tue Feb 08, 2011 3:17 am
Location: Australia
I want to know if jumbling can cause a situation where the cube is only solvable by completing more jumbling moves, or if once the jumbling is unpacked and the cube shape restored if the solve is straightforeward `as always`? Because I believed it might create a `type of parity`, but I haven't come across it yet. (For the Dayan Gem 1 or 2).
*EDIT Sorry, I meant: I get it all the time in the Gem 1, why not in the Gem 2.. You answered my question with intuition regardless Konrad, so thanks.
Cheers,
Burgo.

_________________
1st 3x3 solve Oct 2010 (Even though I lived through the 80s).
PB 3x3 55sec Jan 2011 (When I was a kid 1:30 was speedcubing so I'm stoked).
1st 3x3 Earth (nemesis) solve Jan 2011 My You Tube (Now has ALLCrazy 3X3 Planets with Reduction)

Last edited by Burgo on Mon May 02, 2011 2:36 am, edited 1 time in total.

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Sun May 01, 2011 8:14 am

Joined: Mon Feb 02, 2009 3:50 pm
Emile wrote:
The case shown is possible without the illegal potentially puzzle-damaging move. I have encountered it on my Dayan Gem II adventures.

Great, how? Can you give an alg, I never stumbled on this situation legally, can be a concidence ( not very probable considering the number of solves).

I think the puzzle can be solved without jumbling, please see my comment in the solving forum.

_________________
view my collection at http://picasaweb.google.co.uk/maarten1729

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Sun May 01, 2011 12:20 pm

Joined: Thu Sep 17, 2009 6:07 am
Location: Germany, Bavaria
maarten wrote:
Emile wrote:
The case shown is possible without the illegal potentially puzzle-damaging move. I have encountered it on my Dayan Gem II adventures.

Great, how? Can you give an alg, I never stumbled on this situation legally, can be a concidence ( not very probable considering the number of solves).

I think the puzzle can be solved without jumbling, please see my comment in the solving forum.

I'm really confused: How on earth can you achieve something like the situation in your picture

by "legal" moves? The two pieces sit at their right location , but they are flipped.
I define legal moves as 180 degree turns of edges (the pieces with four stickers are equivalent to the edges of the 3x3x3. I would not call them "corners") How do you define "legal" moves????
Your picture shows clearly a jumbled situation. How can that be seen differently?

BTW, can you make a turn of the square U face in your picture, if there is a jumbled piece in it (sitting flipped in that square face.) I cannot do that, but maybe I have an especially tight version. (See my post here).

BTW, why do we have three threads in the solving forum about this one puzzle?
(the other from April 27th
the first from April 13th)

I think it is a nice and easy puzzle:
1. unjumble
2. cross
3. edges of the 3x3x3 (pieces with four stickers)
4. pieces with two stickers (=Helicopter centres, but much easier, due to the missing Helicopter corners)

_________________
My collection at: http://sites.google.com/site/twistykon/home

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Sun May 01, 2011 12:44 pm

Joined: Thu Sep 17, 2009 6:07 am
Location: Germany, Bavaria
Burgo wrote:
I want to know if jumbling can cause a situation where the cube is only solvable by completing more jumbling moves, or if once the jumbling is unpacked and the cube shape restored if the solve is straightforeward `as always`? Because I believed it might create a `type of parity`, but I haven't come across it yet. (For the Dayan Gem 1 or 2).

Cheers,
Burgo.
I think that the Gem I can be seen as a Helicopter like puzzle, centres only, no corners.
The moving pieces (24) live in 4 orbits
By jumbling you can switch pieces between orbits and you cannot reverse this by "legal" moves.
On the Gem II this is different because you have the additional square turns. I cannot prove it mathematically, but I share maarten's assumption that any situation can be solved by legal moves only, after you have achieved its ordinary shape.

_________________
My collection at: http://sites.google.com/site/twistykon/home

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Sun May 01, 2011 4:51 pm

Joined: Sun Mar 15, 2009 12:00 am
Emile wrote:
The case shown is possible without the illegal potentially puzzle-damaging move. I have encountered it on my Dayan Gem II adventures.
If you define "legal moves" as 180 degree turn of the edges, only (you could call them Helicopter moves), the shown situation is certainly not poosible. 180 degree edge turns will never change the shape of the Gem II and the shown situation is shapeshifted.
Any other moves of edges can only be jumbling moves. Or how do you define "legal"?

Oh I obviously agree! When I said "legal" I meant moves that are possible without making parts of the mechanism cry. I might be unfamiliar with official terminology... Are any jumbling moves "illegal" even though they do not strain the puzzle?

Anyway, here's a link to me fixing the case by unjumbling, then doing a simple 3-cycle. It really isn't a bad case:

_________________
WCA

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Sun May 01, 2011 4:52 pm

Joined: Mon Feb 02, 2009 3:50 pm

I achieved the situation in the picture by forcing an illegal move ( see photo in 1st post). I did loosen the tension of the screws a bit since the puzzle was a bit stiff making the illegal move possible. The sound is not good though . My question in the original post was: can anyone make this legally or prove that's impossible?

I'm working on the math but can't get it right. Thank you for adding the shape-clause.

Thank you for your thoughts.
Maarten

_________________
view my collection at http://picasaweb.google.co.uk/maarten1729

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Sun May 01, 2011 4:55 pm

Joined: Mon Feb 02, 2009 3:50 pm
Hi Emile,

Jumbling moves are legal.

I confess I made the mechanism cry.

Puzzle still is working fine though.

_________________
view my collection at http://picasaweb.google.co.uk/maarten1729

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Sun May 01, 2011 5:00 pm

Joined: Mon Feb 02, 2009 3:50 pm
Ho Emile,

Just managed to view your vid, you answered my question!
Thanks!

_________________
view my collection at http://picasaweb.google.co.uk/maarten1729

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Mon May 02, 2011 3:26 am

Joined: Thu Sep 17, 2009 6:07 am
Location: Germany, Bavaria
maarten wrote:

I achieved the situation in the picture by forcing an illegal move ( see photo in 1st post). I did loosen the tension of the screws a bit since the puzzle was a bit stiff making the illegal move possible.
....

Thank you for your thoughts.
Maarten
Aaaah, I see now what you mean by illegal moves. My puzzle does not allow them (it is too stiff) and therefore I had misinterpreted "illegal" as "jumbling" moves.

Can we agree on the terminology and notation? (Because the puzzle is so easy, we will probably not need much notation of algorithms, but it can be confusing if different people use different notations.)

My proposal:

- Gem II is a combination of an edges only 3x3x3 and a Helicopter without corners.

- we have three piece types:
o the rectangles can be named as "outer centres" (They are part of the 3x3x3 centre and can be done very easily in the first steps. No algorithms needed.) They build the square faces of a 3x3x3, which can be named as on a 3x3x3 by U, D, F, B, L, R
o The pieces with the four stickers correspond to the 3x3x3 edges. They can be named like edges on a 3x3x3 by the two face names they are sitting in, e.g. FU, RU. Non jumbling moves can be named - as somebody has proposed - by [FU], [RU] etc
o the pieces with two triangular stickers correspond to the centres of a Helicopter. It would be confusing to call them "Helicopter centres", we could call them just"triangular pieces". I do not think they need to be named further, but if that is ever necessary, we could name them after the two intersecting moves they can be turned by, e.g. {[FU], [RU]}

- Jumbling moves could be named like j[FU] , describing a clockwise move of [FU] to the next jumbling position and
j'[FU], the same thing anticlockwise.

_________________
My collection at: http://sites.google.com/site/twistykon/home

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Thu May 12, 2011 11:26 pm

Joined: Thu Dec 31, 2009 8:54 pm
Location: Bay Area, California
maarten wrote:
Last Thursday, Dayan’s Gem 2 arrived. I had great fun solving it. In the end I needed to add two alg’s to my gem-1 repertoire (a 3-cycle for the pieces with pentagonal faces, and a 3-cycle for the rectangular centre pieces). When scrambling I accidently made a fudging move like on the 1st photo. I didn’t pay much attention, continued scrambling, solved the puzzle and ended in the jumbled situation of the 2nd picture. I fudged back and was able to solve it using only ‘legal’ moves.
[...images snipped...]
My intuitions tells me the 2nd picture isn’t possible without fudging. Can anyone prove that?
Hi maarten, this situation does not require any fudging moves. It can be done in two 3-cycles. I have put my puzzle in the same position:
Attachment:

dayan_gem_edges_flipped_small.png [ 247.51 KiB | Viewed 1680 times ]
I have created a demonstration video showing how I put my puzzle into this position. As you can see no fudging is required. The only jumbling comes in the last 4 moves.

Edit: My apologies to Emile who figured this out and posted a video before me. I had not seen your post.

_________________
Prior to using my real name I posted under the account named bmenrigh.

Top

 Post subject: Re: Fudging and jumbling Dayan's Gem IIPosted: Fri May 13, 2011 3:46 am

Joined: Mon Feb 02, 2009 3:50 pm
Hi bmenrigh,

Thank you for your post, it's double but still a nice vid!

The next question is: how many pairs can you flip without torturing the mechanism? Would love to see a photo!

_________________
view my collection at http://picasaweb.google.co.uk/maarten1729

Top

 Display posts from previous: All posts1 day7 days2 weeks1 month3 months6 months1 year Sort by AuthorPost timeSubject AscendingDescending
 Page 1 of 1 [ 17 posts ]

 All times are UTC - 5 hours

#### Who is online

Users browsing this forum: No registered users and 2 guests

 You cannot post new topics in this forumYou cannot reply to topics in this forumYou cannot edit your posts in this forumYou cannot delete your posts in this forumYou cannot post attachments in this forum

Search for:
 Jump to:  Select a forum ------------------ Announcements General Puzzle Topics New Puzzles Puzzle Building and Modding Puzzle Collecting Solving Puzzles Marketplace Non-Twisty Puzzles Site Comments, Suggestions & Questions Content Moderators Off Topic

Forum powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group