Small and fast NXT cube solver

"Copper Dragon" made a wonderful small NXT based cube solver with an ingenious new mechanism to solve the cube.
below are some quotes how it is made:

The machine can turn the bottom face by blocking the middle layer with the fork and rotating the turn-table. It can not turn the top face at all and the cube itself can only be rotated around the vertical axis. This requires of course a special solving strategy and a special way to scan the colors: It needs to restructure the whole cube while scanning. This scanning process is rather cumbersome and takes up the first 18 seconds.

The solving algorithm consists of 7 phases with precomputed tables that solves a 2x2x2 subcube first, extends to 3x2x2 then F2L and last layer in one step. It tries 4 rotational symetries and chooses the shortest solution. By this an average of approximately 38 turns are needed for a full solve. What you see in the video is indeed a full solve that requires about 18 seconds for scanning, 1 second for computation and 26 seconds for solving. With the 26 seconds I was a bit lucky, but it seldom takes more than 30.

I am using NXC with the enhanced firmware (for the motor control). While the code is pretty slow in execution, it is fast enough for my table-driven solver. Biggest problem was of course the tiny flash memory space. I would have preferred to use fewer and bigger tables for a shorter solution, but this is pretty much the best I could squeeze into the device.

I must also confess that I had to do two things you could consider cheating: The scanning process is not complete since the mechanism can not scan the middle pieces. Therefore I have to insert the cube always with the white face on top and the red face to the right.
Also the current mechanism can not handle an original Rubiks cube because of corner cutting problems. I am using a "Speed Cube Ultimate II" instead which has excellent corner-cutting. Maybe I can overcome the second restriction without loss of speed, but I have no idea how to scan the middle pieces without additional camera/color sensor.

I wonder what could happen if David or Mike, team up with Copper Dragon.

Celebrating MINDSTORMS with a Remix - Part 2

The ROBOTMAK3RS continued their celebration of the 25th Anniversary of MINDSTORMS through these summer and fall remix projects. Each ROBOTMAK3R was tasked with selecting one LEGO set of their choice and combining it with a MINDSTORMS set. Below are the five amazing models they came up with. Remote controlled material handle r by Jozua van Ravenhorst (aka Mr Jo) This remix combines the LEGO Technic Material Handler (42144) with MINDSTORMS EV3 (31313) It uses the power of pneumatic cylinders to move objects around. By using a bluetooth remote control, very precise movements can be made with this model. Touch sensors in the base chassis prevent the turret twisting the cables that go through the turntable to much. The program has several protections to prevent over pressurizing the system for each of the 3 individual pumps and valves that control the 2 booms and claws. The real version of this machine is mostly used in waste material sites to bring the material to machines that sort and

Celebrating 25 Years of MINDSTORMS

In celebration of the 25th Anniversary of MINDSTORMS, we take a trip through history. Please also visit ROBOTMAK3RS Community every week as we highlight different projects all through 2023 in celebration of the anniversary. Some of the early history is based on the content shared by Coder Shah in our MINDSTORMS EV3 Community Group . Some of the text and links may have been edited from his original posts for consistency and clarity. 1984 - Kjeld Kirk Kristiansen watched a TV program called "Talking Turtle," where MIT professor Seymour Papert demonstrated how children could control robot "turtles" using LOGO, a programming language he developed. 1988 - The collaboration between MIT and LEGO resulted in LEGO TC Logo in 1988, which allowed students to control LEGO models using computer commands. The video shows Papert demonstrating TC Logo. 1990 - LEGO TC Logo was hampered since the robots you built had to be tethered to a personal computer. LEGO and MIT

MINDSTORMS Retires!

2023 is the 25th Anniversary of the MINDSTORMS brand. For 25 years, MINDSTORMS has educated and inspired a generation of robot builders, both children and adults. Unfortunately, the LEGO Group decided to end the line on December 2022. Many ROBOTMAK3RS have been passionately involved with the development of MINDSTORMS through the MUP and MCP programs. Even with the newest Robot Inventor line, several ROBOTMAK3RS were invited to submit additional bonus models that were included in the official app. Regardless of the retirement of a major LEGO robotics product line, ROBOTMAK3RS continue to MAKE-SHARE-INSPIRE using all LEGO robotics platforms available to us. Here is the official statement from LEGO. Since its launch in September 1998, LEGO MINDSTORMS has been one of the core ‘Build & Code’ experiences in the company’s portfolio, carrying with it significant brand equity and becoming a stand-out experience for the early days of consumer robotics and leading to current Build & Code

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