A Crash Course in LEGO NXT Robotics - Getting Started

Meri V. Cummings, Ph.D.

NASA-sponsored Classroom of the Future

Center for Educational Technologies

Wheeling Jesuit University

316 Washington Ave.

Wheeling, WV 26003

Phone: 304-243-2499

E-mail: meri@cet.edu

URL: http://www.cet.edu/robotics/

Why Study Robotics?

Robotics is an excellent way to introduce the students to integrated STEM areas (science, technology, engineering, and mathematics)

Students participating in robotics learn about STEM careers and experience the same activities as professionals solving real-world problems

Everyone – girls and boys alike – should get a chance to see how much fun it is learning engineering skills this way!

Organized Chaos Girl Scouts robotics team at the West Virginia FIRST LEGO League tournament - you’re welcome to observe our Power Puzzle competition on Saturday, Dec. 15, 2007!

The Least You Need One computer (ideally, a school computer

lab with LEGO MINDSTORMS Education Software installed)

One robotics kit, LEGO MINDSTORMS Education Base Set ($250), per 2-10 youth - I recommend you start with a small group (e.g., 4 students) – 1 kit per 2 students is perfect – you might also want several Education Resource sets (spare parts)

LEGO MINDSTORMS Education Software to program the robot ($49 single to $265 site license)

The Least You Need (cont’d)

The LEGO NXT robot can also be programmed with ROBOLAB software

One Mindstorms NXT Base Set and one computer (ideally, a school computer lab with ROBOLAB installed and one base set per two students)

ROBOLAB software to program the robot ($69 single to $265 site license) – you need ROBOLAB version 2.9 ($49 upgrade)

The Least You Need (cont’d)

Instructional materials – I recommend the ROBOLAB Video Trainer CD, which has excellent programming video sequences ($50 single or $100 site)

Robotics kits can be shared in your school, county, or state in 6- to 8-week rotations – they can be used all day for different school and afterschool activities

Funding SourcesUtility companies are required to

provide educational grants – some have utility robotics program partner grants (e.g., American Electric Power has an AEP-FLL partner award to customers in its service area) – ask yours!

NASA Space Grant Consortiums fund outreach programs

After you’ve learned the basics, then what? There are lots of robotics competitions kids

can participate in, such as FIRST LEGO League (FLL) and Botball - some are local, some statewide, some are regional

The tournaments tend to include multipart, real-world problems and research and occur over specific time periods - for instance, the FLL challenge is released in mid-Sept. each year and competitions occur from Nov. through Feb.

The Problem-solving Process What is the robot’s task? What behaviors are needed to accomplish it? Create the program – debug then download. Run the program. Is the NXT behaving badly (doesn’t do task)?

Check the robot first. If there’s a problem, can you fix it?

Next, check the program. Problem? Can you fix it?

Last, go back to the beginning and reread the task. Does your program really tell the robot what it’s supposed to do?

Challenge 1: Line ProgramCreate and test a program to make the

robot go forward in a straight line for exactly 1 second

Save your program as your first name and Line (e.g., FileSave as

Maria LineEnter)

Challenge 2: Square ProgramCreate and test a program to make the

robot go in a squareSave your program as your first name

and Square

Challenge 3: Light Dark ProgramCreate and test a program to make the

robot: Go forward until it finds a dark line Stop for 1 second Go forward until it finds light Stop for 1 second Reverse for 4 seconds Save your program as your first name

and Light Dark

Challenge 4: Tracker Program

Create a program to make the robot:Go forward until it finds a dark lineMove forward along the edge of the lineSave your program as your first name

and Tracker

Hints: You need a loop, and it’s easier if the robot starts at less than a 90 angle

Challenge 5 – Bump Program

Create a program to make the robot:Go forward until it finds a wallTurn moving backward for 2 secondsRepeat these behaviors for 5 “wall

bumps”Save your program as your first name

and Bump

Hint: You’ll need to use wait until Touch in for the first step.

Bonus Beep Challenge

Create a program to make the robot:Go forward until it finds a lineStop for 1 second and beepRepeat for 5 linesFor fun, end with a different soundSave your program as your first name

and Beep

ROBOLAB Video Trainer ROBOLAB Video Trainer CD has lots of video

sequences showing you how to program ROBOLAB and how the robot responds to the program

LEGO Mindstorms Education Base Set and ROBOLAB and ROBOLAB Video Trainer software are available from LEGO education (www.legoeducation.com under LEGO Mindstorms)

LEGO MINDSTORMS Education software has a built-in reference tool – Robot Educator, that walks you through simple challenges

Additional software can be found at the Robotics Academy (http://www-education.rec.ri.cmu.edu/ )

Robotics Web Sites NASA Robotics Alliance Project

http://robotics.nasa.gov/home.php NASA Robotics Curriculum Clearinghouse

http://robotics.nasa.gov/rcc/ Mars Exploration Rover Mission

http://marsrovers.jpl.nasa.gov/home/index.html Robotics Academy

http://www-education.rec.ri.cmu.edu/ Minnesota High-Tech Kids

http://www.hightechkids.org FIRST LEGO League http://www.firstlegoleague.org Botball http://www.botball.org/ BEST Robotics http://www.bestinc.org/MVC/

Sample ROBOLAB Programs

Sample NXT Programs

Challenge 2 – Square with a sound

Challenge 1 – Forward for 1 second

Challenge 3 – Detecting Light/Dark

NXT Programming DetailsSelect a motor icon (you’ll see a blue border around it) to open its control panel - displayed at the bottom of the screen

Additional control panels for sensors and wait for

icons have similar displays

Due to the limited amount of memory available for the NXT, all currently installed sound files should be deleted

Sound files take up a lot of space and should be used selectively

Use the same sound file repeatedly in stored programs to cut down on memory usage

NXT Programming Details (cont’d)

Want to Learn More?

If you have a group of West Virginia educators that want to get started, contact me to schedule a workshop and design a program plan that will work for your situation – courtesy of NASA West Virginia Space Grant Consortium!

Hands-on: Your Turn!Use LEGO MINDSTORMS Educator to

program the NXT robot to move in a square

Think about the robot’s required behaviors to move in a square

What motors have to do what for each behavior?

Which behaviors repeat? You can loop them!

ROBOLAB Basics Go to RCX settings in Administrator to unlock

programs 1 and 2. Single-click the silver Programmer button Double-click the Inventor 4 button. Maximize the lower Block Diagram window. Drag the Function bar to move the Functions

palette to the lower right of the window. If the Block Diagram window is accidentally

closed, open it by hitting Window -> Show Block Diagram.

Hit Tab key to switch from hand to cursor tool.

ROBOLAB Basics (cont’d) Hit spacebar to toggle between cursor and

wiring tool. Hit Esc to escape sticky wires. Click on a wire or icon and hit Del to remove it. Drag an icon within a cm of another, then with

the mouse still down, tap the spacebar to shoot a wire between the icons.

Ctrl + B removes broken or partially deleted wires.

Right-click an icon to replace it with another using a new popup Functions Palette.

ROBOLAB Basics (cont’d)

Always break a wire instead of placing a new icon on top of the wire; otherwise, the icon looks wired when it isn’t.

Click on Help-Show context help, then on the icon itself in the block diagram to learn more about a ROBOLAB icon, including seeing what modifiers each icon requires and where to attach them and to see the icon in a sample program.

If the white download arrow under Edit is broken, click on the broken arrow for information about where the program is miswired.