Lego Mindstorms

The original Lego Mindstorms Robotics Invention System was born out of a collaboration between The Massachusetts Institute of Technology (MIT) and the Lego group. In 1985, Kjeld Kirk Kristiansen, then Chief Executive Officer (CEO) of The Lego Group, heard of the work of MIT's Seymour Papert and was struck by how similar his goals of learning through building were to those of The Lego Group's newly formed educational division. The Lego Group began a partnership with Papert's Media Lab, funding their research and sharing ideas.[1]^:14[2][3] Born out of this collaboration (and the work of Papert and collaborator Mitchel Resnik's Epistemology and Learning group) was the idea to have children use the LOGO programming language to command Lego brick robots of their own design connected to a computer.[4] In 1988 the Media Lab created a Lego Brick compatible computer that could be used to control a robot without connection to a desktop computer.[5] There was interest within The Lego Group to commercialize this Brick compatible computer as soon as personal computers became widespread, and in 1996 The Lego Group began developing this computer into what would eventually be known as the Robotics Invention System.[1]^:25

In 1996, the newly formed Home Learning division of Lego Education began developing Media Lab's "Grey Brick" into an official product.[6] At the same time, Media Lab was working with the Epistemology and learning group to develop a version of the "Grey Brick" specifically for classroom instructions and the collaboration between these three organizations led to two separate versions of the brick computer: The Lego Group's Robotics Command eXplorer (RCX) and Media Lab's "Red Brick". The Liquid Crystal Display (LCD) that the two bricks share was specifically requested by teachers interviewed by the Epistemology and Research group, in order to give readouts of the status of the motors or sensors in real time.[1]^:18[7] Both bricks also ran programs created through the use of visual programming, the RCX using a coding software based on MIT's LOGO Blocks. The Mindstorms' project development team had to redevelop the language after finding out it was too complicated for the target audience (10-14-year-old boys[1]^:26) which caused them to miss the original 1997 launch date. Lego Mindstorms' Robotic Invention System 1.0 was released in September 1998.[7][8]

Before Mindstorms, Lego had previously done some experimentation with robotic sets. One of the main foundations of these sets was the Lego Technic system and its 4.5 V and later 9 V system for electrical peripherals that had been evolving through the 1980s.

Cybermaster

Lego Cybermaster

Cybermaster was mainly sold in Europe and Australia/New Zealand and was available for a short time in the United States via the Lego Club magazines. It was aimed at an older audience as an early attempt of merging with robotics and Lego.

The brick shares many, especially software, features with the RCX but differs in appearance and technical specifications: one output (plus two built-in) and four sensors.

• It uses RF (27 MHz R/C band) instead of IR for communication.
• It has two built-in motors with integrated tachometers and speedometers.
• It is limited to passive sensors (a simple A/D with internal pull-up resistors).
• The sensors shipped with it are color-coded and have internal resistors in their open state (allowing the Pbrick to sense which sensor is attached to which port).
• It has a fixed firmware (so it cannot be upgraded or replaced).
• It has limited RAM for programs (395 bytes) and only one program slot.

Despite its obvious limitations it has a number of advantages over its 'big brother', the RCX.

• The RF link has greater range and is omnidirectional.
• The built-in tachometer and speedometer sensors on the internal motors provides the same function as the external rotation sensor to the RCX, but without using up sensor ports.

This makes it very useful for various mobile platforms and performing advanced motion/positioning tasks.

It talks the same protocol as the RCX but cannot communicate directly to it (due to IR vs RF) but with a repeater (a computer with 2 serial ports and a simple program) they can communicate indirectly.

The Robotics Discovery Set was a more affordable and simpler package than the Robotics Invention Set. Instead of being based on the RCX, it had its own programmable brick called the Scout. An even simpler version of the Scout would be featured in two Star-Wars themed Mindstorms sets as well.

The main core of the first generation of Mindstorms sets were the Robotics Invention System sets. These were based around the RCX (Robotic Command eXplorers) brick, and the 9 V LEGO Technic peripherals available at the time. It also includes three touch-sensors and an optical sensor, using the technology from the earlier 9 V sensors from the pre-Mindstorms sets.

RCX

First-generation RCX programmable brick

The RCX is based on the Single-bit Renesas H8/300 microcontroller, including 32 KB of ROM for low-level IO functions, along with 32 KB of RAM to store high-level firmware and user programs. The RCX is programmed by uploading a program using a dedicated infrared interface. After the user uploads a program, the RCX can run it on its own without needing access to a computer. Programs may take use of three sensor input ports and three 9 V output ports, in addition to the IR interface, enabling several RCX bricks to communicate. A built-in LCD can display the battery level, the status of the input/output ports, which program is selected or running, and other information.[10]

Version 1.0 RCX bricks feature a power adapter jack rather than solely batteries. In version 2.0 (as well as later 1.0s included in the RIS 1.5), the power adapter jack was removed. Power-adapter equipped RCX bricks were popular for stationary robotics projects (such as robot arms) or for controlling Lego model trains. In the latter context, the RCX might be programmed with Digital Command Control (DCC) software to operate multiple wired trains.

The IR interface on the RCX is able to communicate with Spybots, Scout Bricks, Lego Trains, and the NXT (using a third-party infrared link sensor). The RCX 1.0 IR receiver carrier frequency is 38.5 kHz, while the RCX 2.0 IR carrier frequency is 76 kHz. Both versions can transmit on either frequency. The RCX communicates with a computer using a Serial or USB IR tower. As the RCX is discontinued, support for the interface is limited on more recent operating systems than Windows XP.

All versions of the RCX have a unique number printed on it, which could be registered on the now-defunct Lego Mindstorms RCX website. This was necessary to obtain technical support. The first RCX produced is marked "000001" and was on display at the Mindstorms 10th Anniversary event.[11]

Lego Mindstorms NXT was a programmable robotics kit released by Lego in July 2006, replacing the first-generation LEGO Mindstorms kit.[12] The kit consists of 577 pieces, including: 3 servo motors, 4 sensors (ultrasonic, sound, touch, and light), 7 connection cables, a USB interface cable, and the NXT Intelligent Brick. The Intelligent Brick is the "brain" of a Mindstorms machine. It lets the robot autonomously perform different operations. The kit also includes NXT-G, a graphical programming environment that enables the creation and downloading of programs to the NXT. The software also has instructions for 4 robots; Alpha-Rex (a humanoid), Tri-Bot (a car), Robo-Arm T-56 (a robotic arm), and Spike (a scorpion)

The Lego Mindstorms NXT 2.0 was launched on 5 August 2009. It contains 619 pieces (includes sensors and motors), two Touch Sensors, an Ultrasonic Sensor, and introduced a new Color Sensor. The NXT 2.0 uses Floating Point operations whereas earlier versions use Integer operation.[13] The kit costs around US$280.

Mindstorms Color Sensor

Brick of Lego Mindstorms EV3

The Lego Mindstorms EV3 is the third generation Lego Mindstorms product. EV3 is a further development of the NXT.[14][15] The system was released on 1 September 2013. The LEGO MINDSTORMS EV3 set includes motors (2 large servo motor and 1 medium servo motor), sensors (2 touch sensors, ultrasonic sensor, color sensor, infrared sensor, and the new gyro sensor) , the EV3 programmable brick, 550+ LEGO Technic elements and a remote control (the Infrared Beacon, which is only on Home/Retail mode). The EV3 can be controlled by smart-devices. It can boot an alternative operating system from a microSD card, which makes it possible to run ev3dev, a Debian-based operating system.

Spike Prime was announced in April 2019.[16] While not being part of the Mindstorms product line, the basic set includes three motors (1 large 2 medium) and sensors for distance, force and color[17] a controller brick based on an STM32F413 microcontroller[18] and 520+ LEGO Technic elements.

Lego Mindstorms Robot Inventor was announced in June 2020[19] and released later in autumn. It has 4 medium motor from Spike Prime, 2 sensors (distance sensor and color/light sensor) also from spike prime, a Spike Prime hub with a 6 axis gyroscope, an Accelerometer, and support for controllers and phone control. It also have 902+ LEGO Technic elements

Mindstorms kits are also sold and used as an educational tool, originally through a partnership between Lego and the MIT Media Laboratory.[21][22] The educational version of the products is called Mindstorms for schools or Mindstorms Education, and later versions comes with the ROBOLAB GUI-based programming software, developed at Tufts University[23] using the National Instruments LabVIEW as an engine. In addition, the shipped software can be replaced with third party firmware and/or programming languages, including some of the most popular ones used by professionals in the embedded systems industry, like Java and C. One of the differences between the educational series, known as the "Challenge Set", and the consumer series, known as the "Inventor Set", is that it includes another touch sensor and several more gearing options. However, there are several other standouts between the two versions that one may not recognize unless doing a side by side analysis of what each offers. The version sold through LEGO Education is designed for a deeper level of learning or teaching that often happens in a classroom or school setting. The LEGO Education version comes with support called the Robot Educator. This includes 48 tutorials to walk the learner through the basics of coding to more sophisticated and complex concepts such as data logging. This resource to support the learner and/or educator are not included in the retail version of Mindstorms. It's always a good idea to reach out to a LEGO Education consultant to inquire of other differences as there are several more. The retail version was designed for more of a home/toy use vs the educator model was designed to support deeper learning with extra resources and pieces to do so. This is why the LEGO Education Mindstorms contains more sensors and parts than the retail version.

There is a strong community of professionals and hobbyists of all ages involved in the sharing of designs, programming techniques, creating third-party software and hardware, and contributing of other ideas associated with Lego Mindstorms. The Lego Mindstorms system/website is organized much like a wiki, harnessing the creative potential and collaborative efforts of participants. Lego also encourages sharing and peering by making software code available for downloading and by holding various contests and events.

• FIRST Lego League
• WRO (World Robot Olympiad)
• Robofest
• FIRST Tech Challenge
• RoboCup Junior
• Big Trak
• iRobot Create
• Robotis Bioloid
• The Robotic Workshop
• Robotics suite
• C-STEM Studio

• Bagnall, Brian. Maximum LEGO NXT: Building Robots with Java Brains. Variant Press. 2007. ISBN 0-9738649-1-5.
• Bagnall, Brian. Core LEGO Mindstorms. Prentice-Hall PTR. 2002. ISBN 0-13-009364-5.
• Baum, Dave. Definitive Guide to LEGO MINDSTORMS, 2nd ed. Apress. 2002. ISBN 1-59059-063-5.
• Erwin, Benjamin. Creative Projects with LEGO Mindstorms (book and CD-ROM). Addison-Wesley. 2001. ISBN 0-201-70895-7.
• Ferrari et al. Building Robots with LEGO Mindstorms: The Ultimate Tool for Mindstorms Maniacs. Syngress. 2001. ISBN 1-928994-67-9.
• Gindling, J., A. Ioannidou, J. Loh, O. Lokkebo, and A. Repenning., "LEGOsheets: A Rule-Based Programming, Simulation and Manipulation Environment for the LEGO Programmable Brick", Proceeding of Visual Languages, Darmstadt, Germany, IEEE Computer Society Press, 1995, pp. 172–179.
• Breña Moral, Juan Antonio. Develop LeJOS programs Step by Step, "http://www.juanantonio.info/lejos-ebook/".

Wikimedia Commons has media related to Lego Mindstorms.

• Official LEGO Mindstorms
• Lego Mindstorms at Curlie