1
collecting the equipment for your robot
In Chapters 2 through 5, you’ll create a working robot that can move around a room by itself. But before you start building this robot, you need to determine what you need. There have been various versions of LEGO MINDSTORMS NXT sets in the past, but all the robot models in this book require only one LEGO MINDSTORMS NXT 2.0 kit (LEGO catalog #8547). If you have this kit, shown in Figure 1-1, you’re ready to go. If you have a different version of the NXT system and you would still like to use this book, visit the companion website (http://www.discovery.laurensvalk.com/) for suggestions on how to find the pieces that you’ll need in order to complete the projects in this book.
what’s in the box
The LEGO MINDSTORMS NXT 2.0 kit comes with a lot of TECHNIC building pieces, as well as some electronic ones (including motors, sensors, the NXT brick, and cables). Figure 1-2 shows each type of NXT 2.0 piece. You’ll learn how to use each type of part as you read this book.
Figure 1-1: The LEGO MINDSTORMS NXT 2.0 set
Figure 1-2: The NXT kit contains various types of parts.
NXT robots use motors for movements such as grabbing an object or driving. They use sensors to take input from their surroundings, such as the intensity of a lightbulb, a color, or the distance to an object.
The cables connect the motors and sensors to the NXT brick.
the NXT brick
The NXT brick, or simply the NXT, is a small computer that controls the motors and sensors so that your robot can perform actions by itself. For instance, you could build a robot that automatically turns on a light switch when it is getting dark outside. A sensor (which can measure light) tells the NXT that it is getting dark, and the NXT brick then triggers a motor to press the light switch.
But your robot won’t do anything without a program.
the NXT-G programming software
You’ll find the NXT-G programming software on the CD included in the LEGO MINDSTORMS NXT 2.0 kit (Figure 1-3). You create an NXT program using a computer and the NXT-G programming software. An NXT program contains instructions for all the actions that your robot should perform. Once you’ve finished creating your program, you transfer it to the NXT with a USB cable (supplied in the kit). The combination of motors, sensors, the NXT, and your program form your LEGO MINDSTORMS robot.
NOTE If you’ve mixed up the parts in your LEGO MINDSTORMS NXT 2.0 kit with your other LEGO pieces, you can sort them out using the inventory sheet on the back inside cover.
Figure 1-3: The user guide, the NXT-G programming software, and the USB cable. The user guide contains additional information about the NXT set, but I’ll be covering much of that information in this book.
installing the software
Before you can create programs to control your robots, you need to install the LEGO MINDSTORMS NXT 2.0 software. Insert the CD included with your kit into your CD drive, and you’ll see an installation screen. Just follow the instructions that appear on the computer screen to install the software. You can install the software in any language you like, but this book is based on the English version. If this book asks you to enter a decimal number such as 2.5, but you typically enter numbers with a comma in place of the period, just enter 2,5 the way you are used to doing.
the test pad
You’ll use the Test Pad (Figure 1-4) for some of your robot activities. For example, you’ll create a robot that follows the thick black line on this pad later in this book.
inserting batteries
To power the robot, insert six AA batteries into the NXT, as shown in Figure 1-5. You can use standard rechargeable or nonrechargeable batteries or the LEGO rechargeable battery (LEGO catalog #9798) with the transformer (#9833). You may also use the new LEGO rechargeable battery (#9693) with its transformer (#8887).
conclusion
Now that you’ve collected everything you need to build and program a working robot, you’re ready to start building one. In Chapter 2 you’ll learn more about the NXT, motors, and cables as you build your first robot.
Figure 1-5: You can power the NXT brick with six AA batteries or the LEGO rechargeable battery.