What are the formulas for restoring the second-order Rubik's Cube?

Note: At present, the popular second-order color matching is the same as the third-order, that is, upper yellow, lower white, front blue, rear green, left orange and right red (this course takes white as the base, so please use white as the base for communication and study); The description of the following formula is written in English letters. If you don't understand the symbolic meaning, you can go to the third-order formula description page to start this tutorial.

Figure 1 Since the second-order Rubik's Cube has no central block as a reference, we assume that it has a central block. For example, in the first step, we randomly find a corner block with white, and put the white face down. At this time, we assume that the direction of white flour is white flour and the color of white flour is yellow. Knowing these basic knowledge, we will restore the second-order Rubik's Cube with the ideas and formulas of restoring the third-order Rubik's Cube.

In this step, we will introduce two basic formulas. If what you want to accomplish at present is exactly the same as figure 1- 1 or 1-2, just use the formula directly. If it is the case of Figure 10 1, 103, please follow the instructions.

Figure 1- Figure 1-2

Formula 1- 1: (r u r')

Formula 1-2: (f 'u 'f)

Memory skill: White faces right, and the first step is to rotate the layer on the right.

Memory skill: white face forward, the first step is to rotate the front layer.

Figure 10 1 figure 102 figure 103

Use the quadratic formula 1- 1.

Use the quadratic formula 1-2.

Use the cubic formula 1- 1.

(R U R ')？ What about you? (R U R’)

(F'U'F)U？ (F'U'F)

(R U R′)(R U R′)？ What about you? (R U R’)

Step 2: The upper layer is the same color.

After the four corners at the bottom of Figure 2 were repaired, we changed all the colors at the top to yellow. Let's first observe where the yellow faces of the four corners of the Rubik's Cube are now. If only one corner of the upper layer is yellow, compare Figure 2- 1 and Figure 2-2 to see what it is like. If it is not these two situations, it must be one of the other five situations in the picture below. According to the map of these five situations, put your own. As shown in Figure 203, first, we put two corner blocks on the plane, which are already out of our direction. After using a formula 5-2, the upper layer rotates 180 degrees, which is exactly the case in Figure 5- 1. Then we can use the formula 5- 1 once to complete the plane positioning of the four corner blocks. ?

In fact, many friends can also think of other ways to realize the corner position steps in these five cases. As long as we know how Formula 5- 1 and Formula 5-2 are used to turn colors, it is easy to realize the situation that other situations are first converted into corner positions and other triangles are turned colors. Think for yourself, it's simple.

Figure 2- 1 Figure 2-2

Equation 2-1:r u' u' r u' r u'

Formula 2-2: r' u2R ur' u r

Figure 20 1

Figure 202

Figure 203

tu 204

Figure 205

Equation 2- 1+U2+ Equation 2-2- 1+ Equation 2-2- 1+U2+ Equation 2-2? Formula 2-2+U' Formula 2-2 Formula 2- 1 Formula 2- 1

Step 3: Restore all translated upper corner blocks.

Figure 3 In this step, when we restore the last four corner blocks, we should first observe whether there are two corner blocks with the same color, that is, two adjacent corner blocks have been restored correctly. If there are, as shown in Figure 3- 1, rotate them to their own positions and use Equation 3. If this is not the case, we can use Equation 3 at will, and there will be a situation where two corners have the same color.

Figure 3- 1

Equation 3:R2