The NXT motors, sensors and 'intelligent brick.'

"Alpharex" - a robot built with the NXT set.

Lego Mindstorms NXT is a programmable robotics kit released by Lego in late July 2006.^[1] It replaces the first-generation Lego Mindstorms kit, which was called the Robotics Invention System. The base kit ships in two versions: The Retail Version^[2] and the Education Base Set.^[3]. These can be used to compete in FIRST LEGO Leauge competitions. Mindstorm may refer to Lego Mindstorms NXT, a programmable robotics kit released by Lego MinDStorm, an educational video game published and developed by ASK for the Nintendo DS video game console. ... Image File history File linksMetadata Download high resolution version (2400x1800, 1009 KB) This is a copyrighted image that has been released by a company or organization to promote their work or product in the media, such as advertising material or a promotional photo in a press kit. ... Image File history File linksMetadata Download high resolution version (2400x1800, 1009 KB) This is a copyrighted image that has been released by a company or organization to promote their work or product in the media, such as advertising material or a promotional photo in a press kit. ... Image File history File linksMetadata Download high resolution version (1808x2250, 1187 KB) This is a copyrighted image that has been released by a company or organization to promote their work or product in the media, such as advertising material or a promotional photo in a press kit. ... Image File history File linksMetadata Download high resolution version (1808x2250, 1187 KB) This is a copyrighted image that has been released by a company or organization to promote their work or product in the media, such as advertising material or a promotional photo in a press kit. ... For other uses, see Lego (disambiguation). ...

NXT Brick

The main component in the kit is a brick-shaped computer called the NXT brick. It can take input from up to four sensors and control up to three motors, via cables very similar to but incompatible with phone cords. The brick has a 100x64 pixel greyscale LCD display and four buttons that can be used to navigate a user interface using hierarchical menus. It also has a speaker and can play sound files at sampling rates up to 16 kHz. Power is supplied by 6 AA batteries in the consumer version of the kit and by a rechargeable battery and charger in the educational version.

Technical specifications

• 32-bit ARM7 main microprocessor
• 256 KB flash memory
• 64 KB RAM
• 8 bit Atmel AVR microcontroller @4 MHz
• 4 KB flash memory
• 512 Bytes RAM
• 100×64 pixel LCD matrix display
• Can be programmed using Windows or Mac OS (NBC/NXC supports Linux as well)
• Users create a program with new software, powered by LabVIEW from National Instruments
• A single USB 2.0 port
• Bluetooth (Class II) wireless connectivity, to transfer programs to the NXT wirelessly or offer ways to control robots remotely (through mobile phones and possibly by PDA's)
• 4 input ports, 6-wire cable digital platform (One port includes a IEC 61158 Fieldbus Type 4/EN 50 170 (P-NET) compliant expansion port for future use)
• 3 output ports, 6-wire cable digital platform
• Digital Wire Interface, allowing for third-party development of external devices

The ARM architecture (previously, the Advanced RISC Machine, and prior to that Acorn RISC Machine) is a 32-bit RISC processor architecture developed by ARM Limited that is widely used in a number of embedded designs. ... A USB flash drive. ... The AVR is a Harvard architecture 8-bit RISC single chip microcontroller (µC) which was developed by Atmel in 1996. ... A USB flash drive. ... LabVIEW (short for Laboratory Virtual Instrumentation Engineering Workbench) is a platform and development environment for a visual programming language from National Instruments. ... The National Instruments Campus in Austin, Texas National Instruments, or NI (NASDAQ: NATI), is a producer of automated test equipment and virtual instrumentation software. ... A USB Series “A” plug, the most common USB plug Universal Serial Bus (USB) is a serial bus standard to interface devices. ... Bluetooth logo This article is about the electronic protocol named after Harald Bluetooth Gormson. ... User with PDA Personal digital assistants (PDAs) are handheld computers that were originally designed as personal organizers, but became much more versatile over the years. ... A Fieldbus is an industrial network system for real-time distributed control. ...

Firmware and developer kits

Lego has released the firmware for the NXT Intelligent Brick as Open Source.^[4] For other uses, see Lego (disambiguation). ... Open source refers to projects that are open to the public and which draw on other projects that are freely available to the general public. ...

Several developer kits are available that contain documentation for the NXT:

• Software Developer Kit (SDK), includes information on host USB drivers, executable file format, and bytecode reference
• Hardware Developer Kit (HDK), includes documentation and schematics for the NXT brick and sensors
• Bluetooth Developer Kit (BDK), documents the protocols used for Bluetooth communications

Programming

Very simple programs can be written using the menu on the NXT. More complicated programs and sound files can be downloaded using a USB port or wirelessly using Bluetooth. Files can also be copied between two NXT bricks wirelessly, and some mobile phones can be used as a remote control. Up to three NXT bricks can communicate simultaneously via Bluetooth when user created programs are run.

The retail version of the kit includes software for writing programs that runs on PC and Macintosh personal computers. The software is based on NI LabView and provides a visual programming language for writing simple programs and downloading them to the NXT Brick. LabVIEW (short for Laboratory Virtual Instrumentation Engineering Workbench) is a platform and development environment for a visual programming language from National Instruments. ...

NXT-G

NXT-G v1.0 is the programming software that comes bundled with the NXT. There are two different programming interfaces. One is included with the retail and educational kits and the other can be purchased separately. This software is adequate for basic programming, like to drive motors, incorporate sensor inputs, do calculations, learn simplified programming structures and flow control, etc.) There are several pros and cons to using version 1.0 of this software, some of which are listed here:

A screenshot of the programming environment "NXT-G".

Pros: Image File history File links Size of this preview: 800 × 464 pixel Image in higher resolution (1276 × 740 pixel, file size: 242 KB, MIME type: image/png) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Size of this preview: 800 × 464 pixel Image in higher resolution (1276 × 740 pixel, file size: 242 KB, MIME type: image/png) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...

• Can transfer data via Bluetooth or USB cable.
• Easy to Use, drag and drop, graphical environment.
• Pipes show data flow from block to block.

Cons: Bluetooth logo This article is about the electronic protocol named after Harald Bluetooth Gormson. ... Note: USB may also mean upper sideband in radio. ... In computer graphical user interfaces, drag-and-drop is the action of (or support for the action of) clicking on a virtual object and dragging it to a different location or onto another virtual object. ...

• The programs executed on the NXT can be much larger than when compiled by another third party programming language. (e.g. 12kb versus 2kb)
• Programs take substantially longer to load than other third party programs.
• When creating large programs, NXT-G tends to have errors that make it crash, and lose unsaved data.
• NXT-G software usually runs sluggishly, even on powerful PCs.

Most of these issues have been addressed in the recently-released NXT-G v1.1 version of the software.^[5]

Sensors

The kit includes three identical servo motors that have built-in reduction gear assemblies and can sense their rotations within one degree of accuracy. The kit also includes four sensors, each with a different capability. The touch sensor detects whether it is currently pressed, has been bumped, or released. The orange Enter button and the gray right and left NXT buttons can be programmed to serve as touch sensors. The light sensor detects the light level in one direction, and also includes an LED for illuminating an object. The light sensor can sense ambient light with the LED set to off, or reflected light with the LED set to generate light. The sound sensor has a microphone and can be used to detect a sound's amplitude (loudness). The ultrasonic sensor can measure distances and detect movement. Small R/C servo mechanism 1. ...

Third party companies also manufacture sensors, such as the Color, Compass, and Accelerometer sensors sold by Lego.

Parts

Included in the base kit:

• 519 LEGO Technic parts (and Bionicle parts, including Visorak pincers)
• Three servo motors
• Ultrasonic distance and movement sensor
• Sound sensor, with sound pattern
• Light sensor, detecting light intensity
• Touch sensor (press/release/bump detection)

Third-party parts are sold separately:^[6] Example of studded construction. ... Bionicle is a line of toys created by the Lego Group that is marketed towards those in the 7–17-year-old range. ... A web of Visorak, with a Keelerak in the foreground. ...

• Compass sensor
• Color sensor
• Accelerometer sensor

References

• Bagnall, Brian. Maximum LEGO® NXT: Building Robots with Java Brains Variant Press. 2007. ISBN 0-9738649-1-5

Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... is the 127th day of the year (128th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... is the 163rd day of the year (164th in leap years) in the Gregorian calendar. ...

Further reading

• More information can be found the Lego Mindstorms website
• Lego FAQ website.

External links

• Lego Mindstorms
• Lego Mindstorms NXT at the Open Directory Project
• Mindstorms at the Open Directory Project