The LEGO Mindstorms NXT 2.0 Discovery Book [Paperback]

The building and programming instructions that come with the original LEGO MINDSTORMS NXT 2.0 set are nice, but contain only 4 models and basic programming instructions for those. After finishing those models I wanted more and this book is just the thing.

It contains very clear printed instructions for the models it explains (I personally prefer that to having to sit in front of my PC while building) it provides explanations of how the programming blocks work in a much easier to understand format than the NXT-G help files (it feels like someone takes you by the hand to personally show you around instead of having to dig your way through the documentation) and goes way beyond what you learn in the instructions that come with the NXT set by explaining how to use wires to pass data between blocks.

Rather than just telling you how to put the programming blocks together the book teaches you how the program works using easy to understand diagrams.

Last but not least, the book contains a considerable number of interesting robots that are fun to build and additional challenges to expand on them. To make this even easier, there is a companion website where you can ask questions and propose solutions.

I really like the first and last pages on the book (inside cover and inside back cover) which provide you with a reference chart to easily identify parts of different lengths and a complete inventory of the NXT 2.0 set.

If you have bought a Lego Mindstorms set over the last year, the chances are that it has been the NXT 2.0 kit. The previous 1.0 kit is increasingly hard to find. The problem is that many of the resources in the Internet and in Lego Mindstorms books has to date been largely based on the previous kit which has a different range of parts, and which also has an earlier (although compatible) version of the software. Thus the release of Lauren Valk's new book is welcome not least for the fact that it is fairly and squarely based on the NXT 2.0 8547 set.
The book describes itself as a beginner's guide to building and programming robots. It certainly fulfils this function and is an excellent guide to all of the features incorporated in the NXT 2.0 software. It starts by giving clear instructions for the building of an explorer robot with which to explore the fundamentals of writing a simple program, and the reader is quickly able to drive the robot forwards, backwards and to make simple turns. Right from the start the reader is encouraged to experiment and throughout the book there are numerous suggestions for tasks that can be tried, all of which will increase the readers confidence, experience and problem solving skills.
The early programs are enhanced with the addition of sound and visual output using the built in speaker and screen on the NXT brick. A following chapter introduces the use of the wait block and also simple loops, as well as the ability to perform parallel program sequences that can happen simultaneously. Also introduced at this stage is the use of the "my block" facility whereby the user can create their own program blocks containing a sequence of blocks which can then be incorporated into other programs. All of this occupies the first 50 pages of this 300 page book.
In the second section of the book, the explorer robot is then modified to include a range of sensors. First the ultrasonic sensor is added to enable the robot to "see" where it is going, and programs are developed to help it avoid obstacles. These are fully detailed, and again open-ended extra tasks are suggested for the reader to experiment with.
Bumpers are then added to utilise the two touch sensors, and all the while, the programs and optional tasks become more ambitious as the reader gains in confidence. The sensor section completes by introducing the colour sensor, which is mounted on the explorer, and the reader is taken through several tasks including the development of a line following program. The use of the buttons on the NXT brick as well as the rotation sensors built in to the motors is also fully explored.
At this stage the reader has completed 85 pages, and Laurens moves on to complete the second section of the book by introducing a couple of more meaty projects, starting with building the shot-roller - a robot defence system. Full clear building instructions enable the reader to construct this robot, and here it should be said that although the book is in black and white, I had no difficulty in following the process, and the book even has a look up diagram on the front inside colour which lets you see the particular shade of grey that each coloured piece is represented by. In this section details are given on the use of the programming palettes in the software and the use of the colour lamp and motor block. The main shot-roller program is then developed with full explanations at every stage. Alternatives for an intruder alarm and for a remote control mode are also explored. I found this project to be great fun! As a parting shot (forgive the pun) Laurens invites the reader to explore how far the shooter can shoot as the angle of the turret is changed. Also to explore adding the ultrasonic sensor to the robot, and also, in a very open-ended way to explore making a catapult in conjunction with other non-lego parts such as rubber bands and plastic spoons. The second project in the first section of the book is Strider: a novel six-legged walking creature. Here I should say that throughout the book I was very impressed with the many novel and original building techniques that Laurens employs in these robots. There are many examples of very interesting ways of mounting motors and the NXT brick, and I look forward to incorporating some of them in my own future designs. Strider is based on an unusual triangular frame. After a discussion on the walking mechanism employed the program is developed to produce a walking robot, enhanced with coloured lights. As by now the reader is accustomed, there follow a range of investigations, including producing a version which can walk in six directions, or a version which is afraid of a light and stops walking when illuminated, or a further version which speeds up the brighter the light shining on it.
The third section of the book is entitled Creating Advanced Programs. This uses a test bed called Smart-Bot which builds a small platform with two motors and some sensors with which to explore advanced techniques. One motor has the light sensor mounted on it, so that it can be angled at different heights. The other has a wheel attached that can be used to rotate the motor to allow rotational inputs to be made and measured. A touch sensor and the ultrasonic sensor complete the line up. Once the bot is built, the use of data-hubs is introduced, and a range of investigations show how sensors motors and the NXT display can be connected so that they can interact by the use of data wires. Further chapters introduce the use of data wires with loops, switches and logic elements, interesting investigations involving the use of random sounds or the control of a light by means of two buttons. This section is drawn together by the development of a simple reaction game using the NXT screen and left and right buttons, complete with on screen scoring.
At this stage the reader should be proficient at all of the programming techniques available on the NXT brick, using the supplied software. The fourth section of the book, which consists of the final 100 pages or so, contains three major advanced robot projects. Snatcher is an autonomous robot arm, which has an ingenious arm and jaws assembly which requires just one motor to operate it, unlike the normal two, and this leaves the remaining two motors to drive the supporting platform. The robot incorporates the ultrasonic sensor which detects the position of the objects to be grabbed, the colour sensor to detect their colour, and a push button sensor to detect when the arm is in the fully elevated position. This was a very neat robot, which was a pleasure to build, and, in keeping with the rest of the book, the accompanying program was developed and tested piece by piece. As ever, three subsidiary projects were suggested for the reader to pursue.
A hybrid brick sorter formed the second of the three advanced projects. This requires the user to obtain a small number of extra coloured lego bricks (2x2 and 2x4 studs) that are sorted by the robot. Once again the construction details were very clear, and the design was very elegant, particularly the way in which the wheel motor and the lock motor are mounted. The logic for the program is clearly illustrated and it is developed in a modular fashion with separate "my blocks". Four further exploration projects are suggested using the robot.
The final project is scary! You build a compact chimney climber. This robot climbs the space between two parallel walls about 32cm apart. The ultrasonic sensor detects when it reaches the top and it then descends to the ground again. The potential for catastrophe seemed to be only too apparent, but by this stage I knew that the model would be well engineered in keeping with the other excellent robots in the book, and also that the program would be well developed. There were plenty of warnings about keeping your hands under the robot as it climbed, or using a cushion in case it fell, but in the event I found that the system performed very well, and it was certainly impressive watching the robot climb up the space. I was even confident enough to modify the program with a small improvement. Even for this robot there were suggestions for further exploration, such as programming in an altimeter, or building an aerial tram!
In conclusion this book is a real gem. If you want to learn how to program using the Lego NXT 2 supplied software this book will teach you how, and if you follow the various discovery paths you will end up able to develop and adapt your own programs with confidence. You will also see some very elegant robot designs, and pick up some building techniques that will enable you to start designing your own robots.
The book has an accompanying website which at the time of writing has downloads for all the main programs and for many of the discovery projects. There are plans to extend the website with a user forum and various other sections over the coming months. There are contact details for the author, and from personal experience I know that he is happy to discuss and comment on issues that may arise from the book. Although the book is called a beginners guide I think that anyone, no matter what their experience of Lego Mindstorms is, will find this book very worthwhile to work through. I can thoroughly recommend it.

I've had a Mindstorms NXT 1.0 kit since it came out and while I've enjoyed building projects with it I've struggled to find a way to get my kids (9 years old) involved under their own steam, until I brought this book. NXT 2.0 Discovery Book takes you by the hand right from the start and walks you through everything you need to know to build your own robots, starting with a very simple Logo Turtle style robot right up to a colour sorting robot. Everything is explained in detail and is interesting to look at, I think I've had to help my kids twice when they got stuck, pretty good considering the subject matter.

While this book is aimed at NXT 2.0 it will work with 1.0 assuming you buy the extra touch sensor and the new colour sensor, I'd also recommend getting the latest software as well. A couple of the builds need minor adaptations to work with the static components from 1.0 but nothing a reasonably competent Lego builder can't handle.

The book covers everything from how the sensors work, loops, and even data wires/hubs. Only thing its missing is more advanced stuff on dynamic programming but then that's more than covered by other (advanced) books and needs additional hardware anyway.

Essential purchase for all new Mindstorm NXT owners.