Introducing LEGO COPYRIGHTED MATERIAL

1

Did you get a box that looks like the one shown in Figure 1-1?

Figure 1-1: The LEGO MINDSTORMS EV3 set, item number 31313

C H A P T E R

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Introduciing LEGO MINDSTORMS EV3RMS EV3

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2 Exploring LEGO MINDSTORMS EV3

If you did, you are ready to use this book. Several versions of the LEGO

MINDSTORMS set are available, but throughout this book we use the

LEGO MINDSTORMS EV3 set, which has a LEGO item number of 31313. This

chapter provides a brief overview of the equipment in the set and what it does.

Understanding the EV3 Set: It Begins WhenYou Open the Box

The EV3 set consists of various components. You may have seen some of the

components in other LEGO sets, but even those familiar with the previous ver-

sion of LEGO MINDSTORMS will fi nd some parts that they have never seen.

Before you use your new set, it is important to know what you have. The key

components include the following:

■ The electronic components that come with the EV3 set

■ EV3 software

■ TECHNIC building parts

■ Building instructions

■ A test board

By understanding the various components, you will be able to design your

robot more effi ciently. Let’s take a look at these components in more detail.

EV3 Electronic Parts

One of the most important characteristics defi ning a robot is that it processes

commands and generates movements. The electronic components that come

with your EV3 set will enable you to build robots that process the commands

that you write and generate movements that are defi ned in those commands.

The EV3 Brick

The EV3 brick, shown in Figure 1-2, acts like the robot’s brain. Like the way

that our brain tells our body what to do, the EV3 brick instructs a robot how to

behave. The difference between our brain and the EV3 brick is that our brain

behaves on its own, whereas the EV3 brick only interprets the programs that

you write. Note that you will need six AA 1.5V batteries to run the EV3 brick.

Motors

You will program the EV3 motors, shown in Figure 1-3, to create the movements

of your robot. Saying that the EV3 brick is the brain of a robot, the motors are like

Chapter 1 ■ Introducing LEGO MINDSTORMS EV3 3

muscles. As our muscles generate all of our body movements, the motors will power

all the actions of your robot such as driving, walking, lifting, spinning, and so on.

Figure 1-2: The EV3 brick

Figure 1-3: The EV3 Motors: The large motors and the medium motor

As you can see in Figure 1-3, the large and medium motors have quite dif-

ferent appearances. The large motor is bigger than the medium motor, and

the body size represents the strength of the motor. Also, the two motors move

in different directions: The large motor’s movement is parallel with the body

of the motor whereas the medium motor’s movement is perpendicular with

the body of the motor, which allows you to effectively design a robot that can

achieve your goal.


Sensors

Within the EV3 set, you will fi nd a touch sensor, a color sensor, and an infrared

sensor (see Figure 1-4). As you build the projects from this book, you will learn

to use these sensors to make your robots interactive. In other words, your robot

will be able to decide its action based on the inputs from its surroundings. For

example, let’s say you have a vehicle type robot. With an infrared sensor, it can

detect how far an object is in front of it. Based on the data from the sensor, the

robot can play a louder sound when it gets closer to the object.

Figure 1-4: The EV3 sensors

Remote Infrared Beacon

The remote infrared beacon, or the IR beacon, is one of the cool new features of

EV3 (see Figure 1-5). You can use it as a remote control for your robot, and you

can program various commands for each button or combinations of buttons.

In addition, you can set your robot to detect where the IR beacon is. Note that

you should not use this device with the infrared sensor.

Figure 1-5: The remote infrared beacon


Cables

This set contains two types of cables (see Figure 1-6): connector cables and a

USB 2.0 cable. Connector cables are for plugging the motors and sensors into

the EV3 brick. The USB cable is used to download a program to the EV3 brick

from your computer.

25cm/10inConnector

Cable

35cm/14inConnector Cable

50cm/20inConnector Cable

l2.0 USB Cable

Figure 1-6: The connector cables and the USB 2.0 cable

EV3 Software

To give your EV3 robot instructions, you must use the EV3 software specifi cally

designed for this set. If you are looking in the box for an installation disc, you

will be looking for a while. LEGO offers its free EV3 software only as a down-

load from www.LEGO.com/mindstorms. From the main page, click the Downloads

link to display the page shown in Figure 1-7. Then click the Download button.

Don’t worry if you don’t have the EV3 software available when you want to

test out your robot. There is an app that comes with the brick that allows you

to program your robot. The program that you can create with this app will be

simpler than with the EV3 software, but it is still very useful! You will see where


you can fi nd this app on the brick when we go over the EV3 brick interface in

“Building the Auto-Driver: A Starter Vehicle.”

CLICK

CLICK

Figure 1-7: Downloading the EV3 software


WHICH VERSION DO I DOWNLOAD?

The EV3 software is compatible with both PC and Mac. If you use a Windows operatingsystem, it should be one of the following versions: Windows XP (32-bit); Vista (32-/64-bit), excluding Starter Edition; Windows 7 (32-/64-bit); and Windows 8 desktop mode, excluding Starter Edition. If you use a Mac operation system, it should be one of the following versions: Mac OS X 10.6, 10.7, or 10.8 (Intel only).

The download page contains options for choosing the operating system (Mac

OS X and Win32) and language. If you download the installation fi le for PC,

you will see a fi le with a .exe extension; for Mac, it will be a .dmg fi le. After the

fi le downloads to your computer, just double-click the fi le icon and follow the

instructions that pop up on your screen.

TECHNIC Building Parts

Other than the electronic parts, the box contains various parts for building

robots. Before jumping into building robots, let’s overview some of the main

building parts that you will use often and their important features.

Studless TECHNIC Beams

When building EV3 robots, you will use studless TECHNIC beams (see Figure 1-8).

The offi cial name is quite a mouthful, so from here on out we will just refer to the

part as a beam. These parts are crucial for building complex, moving robots that

would not be possible using standard LEGO bricks.

Figure 1-8: Various studless TECHNIC beams


Connector Pegs

The set contains many small parts, but the majority of the pieces look like the

connector pegs shown in Figure 1-9. Note that they are also called connecter pins.

Figure 1-9: Different types of connector pegs

These components are called connector pegs because they allow multiple parts

to snap together. Connector pegs come in different sizes with different features,

but one of the important things that you need to know is how to distinguish

the following: The connector peg and the connector peg with “friction.” If you

look at the regular connector peg, its surface is smooth or “frictionless” (see

Figure 1-10), whereas the connector peg with friction has little bumps on the

surface.

Connector Pegwith Friction

Connector Peg

bumps

bumps

Figure 1-10: Connector peg with friction versus a frictionless connector peg

If you put a connector peg on a beam, you will notice that the beam can be

turned easily. However, if instead you use a connector peg with friction, it will

be more diffi cult to turn the beam because the little bumps on the peg create

more resistance.


Mechanical Pieces

When you design your robot’s movements, the mechanical pieces allow for a

more effi cient construction (see Figure 1-11). These pieces provide, but are not

limited to, mechanical advantages such as switching the direction of gear move-

ment, building a drive train, changing the speed of gear movements, and so on.

Figure 1-11: The EV3 mechanical pieces: spur gears, double bevel gears, worm gear, cam, and so on

MAKING AN EV3 ORGANIZER

The EV3 set comes with many diff erent pieces. Based on my experience, I prefer tohave all the parts organized separately as I design a robot. I can thus see what parts Ihave left at a glance and not lose my thought process by spending time searching for a piece. You can probably use plastic cups or small containers, but I highly recommend that you take as your EV3 organizer an organizer that is normally used for spare parts (see Figure 1-12). This way, you can keep parts organized by size or type and store everything all together. You can fi nd these organizers at any well-stocked hardware store or on the Internet.

Continues


Figure 1-12: Organize your EV3 set.

The Building Instructions and the Test BoardIn addition to parts, the EV3 box also contains a booklet with building instructions

for one robot and simple directions for using the EV3 brick (see Figure 1-13). To

augment the basic instructions in that booklet, this book provides in-depth cover-

age of the EV3 brick. Inside of the fi rst layer of the package, you’ll fi nd a test board

(see Figure 1-13). You use this board to test out your robot later on in this book.

The BuildingInstruction Booklet

The Test Board

Figure 1-13: The building instructions booklet and the test board

continued


Comparing EV3 and NXT

NXT is the previous version of the LEGO MINDSTORMS set. If you use an NXT

and also have an EV3, you may wonder how these two versions are comparable.

In general, the EV3 equipment performs better than the NXT equipment. In

terms of the brick’s ability to process data, the accuracy of the included sensors,

and the improved design of the electronic parts, EV3 makes for a better robot.

NXT and EV3 motors are cross-compatible and work fi ne for either set. EV3

sensors, however, are not compatible with NXT, although EV3 can use sensors

from the NXT set. Just note that using the NXT light sensor with EV3 can be

quite unstable. EV3’s free software is very powerful control software available

for MINDSTORMS and will work with NXT (see Figure 1-14).

MOTORS

SENSORS

SOFTWARE

EV3 NXT

Figure 1-14: Compatibility chart for EV3 and NXT elements

Summary

In this chapter, you learned about the following:

■ The electronic components of EV3

■ The EV3 software download and installation process

■ Characteristics of the principal building parts

■ Compatibility between NXT and EV3 components

Documents

Introducing LEGO COPYRIGHTED MATERIAL