nxtasy.org | Building a LEGO Mindstorms NXT Community Brick by Brick

Daniele Benedettelli’s book

claude — Sat, 03 May 2008 07:51:28 +0000

“Creating Cool Mindstorms NXT Robots” by Daniele Benedettelli has come out with some delay. The author and editor’s wise decision to take their time to do this book has purified the contents and enhanced its quality… which can be only described with the attribute : excellent !

Danny has developed a handful sophisticated LEGO robots to which he gave life through control- and behaviour-based programs. The reader is led through slowly growing degrees of difficulty and complexity from “Quasimodo” to “JohnNXT”, while learning about the essence of NXT C-programming and concepts as diverse as finite state machine, hysteresis, underactuation, line following, Boolean operators, decision tables… All these topics are well-woven to form a balanced patch-work of knowledge that has characterized so many good robot books. You consequently learn by doing.

The author astutely combines NXT-programming with remarkable LEGO studless building in order to realize and describe more and more complex robots. With a note of humour the reader is accompanied through all the designs, where he has the impression of participating in the development of each prototype, which definitely is one of the best didactical choices. The graphics of this book are of high quality.

The absolute high-light of course is JohnNXT, the LEGO incarnation of the famous “Short circuit”-movie robot. Daniele uses two NXTs (pardon : three!) for this project. Two NXTs control the robot and communicate with each other over the RS485 high-speed connection. A third NXT is used in a “Remote Control” project and sends its commands via Bluetooth to the robot. But JohnNXT also can survive quite autonomously through a behaviour-modelled program.

Well done Danny !

Lego Pong with NXTCam

tingeypa — Fri, 02 May 2008 05:14:46 +0000

Here is an interesting robot from wayneage that plays Pong using a NXTCam camera to track a ball in real time. The NXTCam continuously sends the location (coordinates) of the ball to the NXT brick. The robot keeps adjusting its position to hit the ball when it is close enough. Before the robot starts, the NXTCam is taught the colours to track using another program called NXTCamView (this is not shown in the video). As you can see it works quite well - nice work!

Voyager - a GPS outdoors NXT

guy — Tue, 29 Apr 2008 05:38:56 +0000

Here’s a great project by John Brost. Inspired by Steve H. ‘Green Monster’ he built this model, which also uses Bluetooth GPS (and RobotC) to navigate around.
Voyager uses a 3-motor articulated steering design - one motor drives both wheels on the rear axle through a differential and the front wheels are driven individually by the other two motors. It also has a compass sensor and a GPS connected via bluetooth.

More pictures are found in NXTLog project page. Good work, John!

btw. Technically it IS possible to build a BT GPS NXT-G block. There’s a lot of work involved, and very little potential users. If anyone is interested, email me. I’ve posted a few posts on GPS in NXTasy, and since some implementations do work in NXC (under standard firmware) they can be ported and wrapped into a NXT-G block (but with a lot of effort).

Guy Ziv

2008 FIRST LEGO League World Festival Award Winners

Josh — Thu, 24 Apr 2008 20:32:54 +0000

Here is an article from LEGO about the World Festival in Atlanta.

Click here for the article on their Mindstorms main page, below the article about Dean Kamen.

This link seems to be permanent.

Josh

Team Scores 3 Perfect 400’s at FLL World Festival

Josh — Wed, 23 Apr 2008 04:31:36 +0000

Congratulations to GREEN MAN GROUP who scored 3 perfect 400-point runs at the FLL World Festival this April 16th-19th. They received the 1st Place Performance Award. GREEN MAN GROUP is a part of The New England Robotics Designers - check out their website here.

Here is a link to the World Festival awards page, featuring a picture of the team and their robot.

Josh

Little Joe - a biped walker LDD

TooMuchCaffeine — Wed, 16 Apr 2008 20:38:14 +0000

Here is Little Joe, a biped walker. He was inspired originally by the work of Joe Nagata, but the feet are probably the only bit of Joe’s original that survives.

Little Joe has a pretty smooth and reliable walking action going on which you can see on video here. I’m very pleased with how he turned out. Just wish I’d got him finished in time for the NXTlog competition!

There’s not many instruction sets for bipeds out there (or not that I could find anyway). Hopefully this LDD file will come in useful.

If anyone does build Little Joe, I’d love to hear how you get on…

New pbLua version

guy — Sun, 13 Apr 2008 09:58:07 +0000

Ralph released yet another pbLua version - Beta 15a. The major change in this release is better support for floats (i.e. non-integer variables).

There is now a new (well written) tutorial on using floats in pbLua.

Keep up the good work, Ralph!

Power Functions Rover with 2 US

guy — Sun, 13 Apr 2008 07:06:37 +0000

Here’s a nice projecy by our forums reader markc. It uses PF motors and two ultrasound sensors to navigate around, avoiding obstacles. Nice work!

More details, closeup photos and discussion here.

A Four-Legged Critter

sivan — Sat, 12 Apr 2008 22:43:37 +0000

I was inspired by a NXT robot called RoboDog to build a four-legged critter. I ended up building it without the NXT, but I it still came out cute. I used the Power-Functions battery box and receiver, as well as a Power-Functions motor to rotate the head. But the legs are powered by an RC Buggy 9V motor, which is connected to the Power-Functions receiver by an extension cable. Click the picture for a video.

New pbLua version

guy — Tue, 08 Apr 2008 03:58:43 +0000

Here’s a message from Ralph Hempel:

There’s a new pbLua version Beta14n that fixes a few issues in the file system, as well as adding a new function called Checksum() to sum the characters in a string.

The file system tutorial has a section at the end that shows you how to automatically run a Lua file on power up with no intervention and no console attached. That would have been handy for the UAV project…

Here are the latest new tutorials:

File System
HiTechnic IR Link
Codatex RFID Sensor
Precision Motor Control (like a servo)