--- In [email protected], "Mike Bennett" <[EMAIL PROTECTED]> wrote:
> > To that end, I've been trying to find ways to speed the Last 6 edges > (and 4 centers) up, and thinking a lot about several variations of the > normal method. > > First, there's unconstrained centers. This can shorten some of the > hardest orientation situations from 12 moves down to 5 or 6, but the > recognition seems akin to ZB to me. I need more practice with this, > definitely, but I think that it may take too much time, even with > mastery. I wrote that some of them only are interesting. Case 3a for example, it would stupid to start a 7 moves orientation sequence (including two U2). M' is enough. And the case is rather easy to recognize, with UL and UR on top. If an "optimization" makes you loose time, just don't use it. As I said, sub-4 is possible without these optimizations. Look at this random solve: http://grrroux.free.fr/capcubeM2.avi Orientation: M'UM'UMUM' Insertion: U'M2U' Permutation: M'U2M'2U2M' A rather long finish, but it took only about 3s and my slices are not as fast as Bob's. > The whole Step 4 method takes something like > 18 moves on average, if my math is anywhere near correct. Wrong, it should be around 14 if you mix 4a+4b and 4b+4c. > Instead of orienting and permuting L6E, what if we were to finish off > DF and DB edges, then complete the cube with ELL? The hardest > situations for finishing the two edges should be around 7 moves, with > the average being somewhere around 6. ELL averages about 12 moves, so > that puts the method in similar standing to the normal way. > > But what if we only finish off the DB edge? It can only be in 6 > places, each place having 2 possible orientations. Thus, 12 simple > cases, 11 of which are 5 moves or fewer. The average move count should > be about 3.5, with the hardest situations at 7. You don't need to > orient centers prior to this step, either. And recognition is very > simple. The hardest case to spot is when the piece is already > correct. :) After this, we could use any of the 22 possible cases > found here: http://www-personal.umich.edu/~dlli/NewAlgSet.html > > This would give us an average of under 7 moves to place the DF edge > and orient the LL edges, leaving us with an edge PLL step, as in COLL. > As edge PLL's average 7 moves, our previous step averages 6.5 or so, > and our first step at 3.5, this gives us around 17 again. The > benefits? Aside from the 1/12 chance for a PLL skip, and the > extremely easy to recognize and execute EPLL step, you never need to > change your grip, and after the DF and DB edges are placed, you never > need to adjust the M slice. > > Also, there are a number of lucky cases to exploit. There are only 29 > or so unique cases for when the edges come up correctly oriented after > placing DB. There are some very fast cases for when edges are > correctly placed but incorrectly oriented, and learning the ELL algs > can help out nicely for the 1/10 of cases where the DF edge completes > itself along with DB. The worst case scenario is 26 moves to finish, > and comes up roughly 1/2880 cases, while the odds for a 4 move or > fewer solution are 1/72. I think that EPLL as the last step is not a very good idea, permuting M-edges is much faster. The standard corners-first approach that begins with solving UL or UR (instead of DB), before solving the other and orienting M-edges looks like a better idea to me. If the first piece (UL/UR) is a bit difficult to solve, just put it oriented in U (don't care wether it's inserted between the right corners or not), apply the standard CF orientation sequence without the last 2 moves, and you end up in the middle of step 4b. For this technique, you should need less than 15 moves on average too. > I could definitely use the > services of someone who is good with ACube. ACube is very nice and useful, but it's not the right tool when centers are moving parts. Thanks for contributing! Gilles. [Non-text portions of this message have been removed] ------------------------ Yahoo! Groups Sponsor --------------------~--> Get fast access to your favorite Yahoo! Groups. Make Yahoo! your home page http://us.click.yahoo.com/dpRU5A/wUILAA/yQLSAA/MXMplB/TM --------------------------------------------------------------------~-> Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/speedsolvingrubikscube/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
