The Unofficial Lego Mindstorms NXT Inventor's Guide, by David J. Perdue

Posted January 28th, 2008 by Taran

While this is a late book review for various reasons, it is a timely book review since it is the 50th Anniversary of the Lego Brick. I had originally intended to have this out before Christmas, but life had other plans involving crashed hard drives - amongst other things.

For the audience of this book, LEGO Mindstorms NXT should need no introduction. Its one of the systems that makes children above and below the age of 13 drool, but it is not as simple as snapping together a few Lego bricks. There is the NXT Microcomputer. Sensors for touch, sound, light, and even an ultrasonic sensor for measuring distance. Three servo motors with built in rotation sensors. And then there are all those neat little parts that look very impressive to someone who just opened the box, but may be intimidating when an actual task is at hand. It wasn't too long ago where just being able to have Legos move was a big deal. Now you can automate them.

Enter the The Unofficial LEGO MINDSTORMS NXT Inventor's Guide. Within the book, the author guides one through the steps for creating and rightly notes that Lego Mindstorms NXT are not just about building - they are also about programming.

Within the first 2 chapters, the Lego Mindstorms NXT kit is formally introduced to the reader - something that may be glossed over by excited people but which may prove useful in the long run.

Building

Chapters 3 through 6 go through the components and process for building - from the electronic pieces to tips on building structures that won't crumble under stress. Chapter 6, the gear guide, is really well written and is exceptional for beginners who are trying to muddle their way through gearing concepts. A lot could be learned just in this chapter, since it demonstrates all manner of gears as well as dealing with imperfect gear ratios. The versatility of the Lego gears is truly brought to life in Chapter 6.

Programming

Chapters 7,8 and 9 deal with the programming - from the introduction to more advanced programming to the unofficial programming languages. While the programming language of the NXT system may seem straightforward to someone with a programming background (such as me), Chapters 7 and 8 are invaluable to beginners who may not have programmed before in their life. While the NXT programming interface is relatively simple when compared to most computer languages, teasing out the different aspects is important and are well covered here.

There is information on dealing with the legacy blocks that one may have from the previous Lego Mindstorms kit - a special library is available for download. The Mini Block Library is also mentioned - and this is a must have for anyone doing a lot of programming, since the Mini block library occupies less memory. LabVIEW users also get their own paragraph on where to get the LabVIEW toolkit so that they can develop their own NXT-G blocks. If only I had more time!

Chapter 9 goes through the unofficial programming languages for the NXT. These include the Next Byte Codes (available on Sourceforge), 'not eXactly C' (NXC), leJOS NXJ (a Java port) and RobotC. These different flavors are discussed in depth, and the bricx command center is mentioned for developing outside of the Lego Mindstorms NXT programming environment. While one of the more fun chapters for me, I just couldn't try everything!

Projects

Clearly, this is where everyone wants to be when they get their Lego Mindstorms NXT. This is where it all comes together - making things and seeing them do what is expected or unexpected. There is a story about a cat named Sprocket and my first Lego Mindstorms kit I might share someday...

The Lego Mindstorms method of creating robots is gone over in detail in Chapter 10. Chapters 11 through 16 are the separate projects that you can build from the book. Easily identifiable by name, these are zippy-bot, bumper-bot, claw-bot, Tag-bot, guard-bot and golf-bot. The detail in these projects is amazing - and the explanations are well written.

And the great news: The project part of the book has only 13 pages less than the preceding pages!

Appendices

The appendices cover the Lego Mindstorms NXT pieces (A), the quick reference (B) and internet resources (C).

Overall

What struck me about this book, and this author, is how well some of the more advanced ideas were explained - such as my favorite chapter, 6, on gears. Lego Mindstorms NXT are not simple toys to be placed together haphazardly, and it takes some thought to get the magic out of the separate pieces. The author teases that magic out of the reader, building them up for the next step. The focus on projects does allow people to dive right in and refer back as they have to, but it is better to read this book in the way the author wrote it. It isn't that long, it isn't too complicated and it is well written and should be easily read by anyone at a secondary school reading level (with an interest in robots).

This was a very hard book for me to review because I love Legos. I loved Mindstorms since they first came out, and I was upset to find out that they might have been discontinued. But Legos, for me, have never been something to write about or something that could easily be discussed - they were about showing. With the evolution of Legos, the task of showing has become more difficult - but Mr. Perdue stood up to the task and performed so admirably that this book must not be left dormant on a shelf. That would be a sin.

This The Unofficial LEGO MINDSTORMS NXT Inventor's Guide gets a KnowProSE.com 9 out of 10. The only thing that I think could have made it better would have been it coming with the Lego Mindstorms NXT kit itself.