1. Introduction to LEGO NXT robotics and Robot Sumo for
CJ Chung
Associate Professor of Computer Science
Founder and Director of Robofest
Lawrence Technological University

2. This program is possible thanks to:
a grant from Detroit Auto Dealers Association (DADA) Charitable Foundation Fund,
which is a fund of the Community Foundation for Southeast Michigan.
For more details, check out a press release at:

3. Schedule First Workshop Day (3 hours) Second Workshop Day (3 hours)
Third Workshop Day (2 hours)
Meetings with your school staff/teachers to improve your sumoBot (3 hours x 2 meetings suggested)
Official Competition at your school to select one team to advance to the World Robofest Championship on April 26. General public to be invited.

4. Workshop First Day (3 hours)
Introduction to Robotics
Introduction to Robofest and Robot Sumo
Introduction to Lego NXT
Introduction to NXTG
Basic programs
Motors
Wait
Turns

5. Introduction to Robotics
What is a true robot?
autonomous robot with an on board computer
Mechanical, electrical, and computational components
Six fundamental components of a robot
A brain or brains – computer
Body: physical chasses that holds other pieces
Actuators: motors, hydraulic pistons, pneumatics
Sensors
Power sources
Communication mechanism

6. What is Robofest? 100% Autonomous Affordable
Challenging: Unknown problem
No direct adult help allowed during the competition
Qualifiers and a World Championship
Various categories including Robot Sumo
Two divisions:
5th – 9th grade: Jr. Division
9th – 12th grade: Sr. Division

7. RoboSumo
Push the other robot out of the Sumo ring

8. Specifications Junior Division Senior Division Sumo ring diameter
Junior Division
Senior Division
Sumo ring diameter
77 cm (30 inches)
122 cm (48 in)
Maximum robot mass
1kg (2.2 lbs)
2 kg (4.4 lbs)
Maximum robot width and length
23 cm (9 inches)
30 cm (11.75 inches)
Maximum robot height
no limit
Robot type
Any;
Lego Mindstorms or NXT recommended.
any

9. Why Sumo? The most popular robot competition in the world
Integrator in Science Education – Math, Logic, Computers, Mechanics, and Physics
Good for rookie teams
Fun Motivator

10. Unknown Problem in Robofest Sumo
How to start is unknown
Need sensor(s)
Teams must bring a computer to program the unknown parts

11. Introduction to Lego NXT
Brain – RCX micro computer
Body: Lego Technic pieces
Actuators: up to 3 motors
Sensors: Light, touch, US, Sound, etc.
Power source: 9V (six AA batteries or rechargeable battery pack)
Communication mechanism: USB or Blue Tooth

12. Introduction to “SB2 (Sumo Bot 2)”
Left motor: A
Right motor: C
Touch: 1
Light: 3
Ultra Sonic (distance): 4

13. Introduction to NXTG Programming
Please go through Getting Started and Software Overview after this class

14. First NXT program: Go forward for 2 sec. and stop
Let’s name the program first
Click on Go >> button
You’ll see a programming palette (canvas)

15. First NXT program using SB1: Go forward for 2 sec. and stop (2/3)
Click on Move button
Drag and drop the move block to the canvas

16. First NXT program using SB2: Go forward for 2 sec. and stop (3/3)
Change parameters for the Move
Port
Direction
Steering
Power
Duration
Next Action
Block
Configuration Panel

17. How to run your first program (1/2)

18. How to run your 1st program (2/2)
If “Found New Hardware” pops up, just follow the instruction
Click on “Download” button
Recommended to un-plug the cable from the Bot
Press the orange button 4 times (Turn on, My files, Software files, Run your program entitled go2stop)

19. How to rerun the program
Check the program name on the LCD
Press the orange button just once again

20. How to stop the program
Gray button

21. First NXT Program: Go forward for 2 sec. and stop (Review)

22. Do not forget: Save your programs Meaningful file (program) names
Use comments

23. 2nd Program: ForwardBack
Go Forward 2 rotations
Wait 3 seconds, then
Backward 1 rotation

24. Go Forward 2 rotations, Wait 3 seconds then Backward 1 rotation – ForwardBack

25. Making Turns Turn left Spin left Face left stop Left wheel Right wheel

26. Turn90Left – Using a Motor Block!
Forward 2 rotations,
Turn Left 90 Degrees,
and Forward 2 rotations

27. Forward 2 rotations, Turn Left 90 Degrees, and Forward 2 rotations – Turn90Left

28. How do we make to turn 90 degrees?
Timer?
Trial errors
Let’s do the math!!!
Width of the robot: 14 cm
Diameter of the wheel: 5.5 cm
Perimeter of the wheel: 5.5 cm x pi = 17.27
23.55 / =
Travel distance needed:
(14 x 2 x pi) / 4 = cm
Number of rotations needed?
21.98 / =
14 cm

29. How about 180 degree turns using a motor block?
Forward 2 rotations,
Turn Right 180 Degrees,
and Forward 2 rotations
14 cm
What is the rotation value for the Motor Block?
1.27 x 2

30. “Spin” 180 degrees using Move/Steering
Forward 1 rotation,
Spin right 180 degrees
Forward 1 rotation
Travel distance needed:
(14 x pi) / 2 = cm
14 cm
Number of rotations needed?
21.98 / =

31. Spin180right

32. Class Challenge: A Simple Maze
Start line
box
box
Place a business card as a target
point to reach

33. Online Resources
great tutorial on how to program in NXTG
nxtasy.org: with more information than you could ever want about LEGO robots and programming; a great place to ask questions