Design and Innovation Project

Team 1 - Cheetah

Hardware

The sumo robot built by our team consists of three induction motors, an NXT Block, and a touch sensor. 

It is held in place by  interlocking Lego parts. Gears  are used to increase the speed and torque of the 

induction motor. Two  induction motors are used to rotate the robot’s wheels, and are therefore placed 

beside the NXT block. Due to the relatively lighter weight of our NXT  robot, the team decided to focus 

on speed and reaction of the robot, and connected a gear of larger radius on the induction motor to a 

gear of smaller radius on the wheel.   


Software

C# is more favored by  programmers in creating interface applications as its programming style is more
 
widely used. It is easy on the learning curve with knowledge of  C++/Java and also many APIs are
 
available in C#. Hence we have chosen to write  the interface in C#.

Team 2 - Rikishi

Hardware

The design of our  robot (sumo-bot) integrated all the three motors as well as all the four sensors. Of the

 four sensors, three were used as inputs whereas the fourth was  used as an output. Creating a stable

 and interactive (sensors) design that  could endure a sumo fight constituted the originality of the 

hardware. 

We built a robot with a low centre of gravity preferably with a  slightly wide base for stability. We also

 included a strong flipper that could  push as well as topple with sufficient amounts of power. And

 in order to regulate this power, the use of gears was necessary.


Software

Visual Programming Language  was extremely user-friendly and provided a  graphical environment for
 
programming the Wiimote and the NXT Robot. VPL allows  the use of “activities” (created by user, or
 
pre-defined) that can represent  services, data flow control, functions or other code modules. A toolkit,
 
that  is freely available online, can be used by programmers to develop programs for  the Lego
 
Mindstorms NXT robots. It provided easy to configure activities that  can be used to directly send output
 
or take input from the robot. We made use  of this kit, along with another service that can provide access
 
to all the  features on the Wiimote, to finally create a program that could control all the  features available
 
on the Wiimote and the NXT Robot.

Team 3 - Hawbot

Hardware

The group used the Lego Mindstorms Education NXT Base Set  9797 for the project. This essential

 core set serves as the base for endless NXT robotic creations. The three interactive Servo Motors 

provides the robot with the ability to move. The feedback from the built-in rotation sensors, allows the 

NXT to control movements very precisely. The motor rotation is measured in degrees. 

For the project, port A is used for  the motor controlling the arm lever. Port B is used for the motor on 

the right  side which controls movement of the right wheel. Similarly port C is used for the motor on the 

left side. Since the robot is meant to be controlled via the Wiimote,  no sensors were used in its 

construction.

The Technic building elements are used to build the frame to hold the three motors and the NXT brick 

in place. A  gear system is used for all the motors so as to increase its power but  sacrificing speed in 

the process.  


Software


The Wiimote communicates with the PC via Bluetooth and  the buttons on the Wiimote are mapped 

correspondingly to the keyboard, using  the GlovePie software. When the buttons on the Wiimote is pressed, 

it activates  the various commands on the OnBrick software. The OnBrick software on the PC  then sends 

the commands to the Lego NXT Brick via Bluetooth. Therefore, the  actions of the robots would correspond 

with the buttons pressed on the Wiimote.

Team 4 - Mammoth

Hardware

A four-wheel drive system was used to prevent robot motion from being incapacitated when two of its

wheels are already lifted off the ground. This system also allows for sharper turning which will help prevent

flanking from opponents. Gears were added on both sides to ensure wheels on each side having the same

orientation. Front wheel guards were installed to reduce the exposed areas which might be exploited by

opponents. Also the front guard would prevent the robot from flipping itself over by moving on top of

opponent robots. Touch sensors were placed at strategic areas such that contact with opponent robots at

these areas will cause the Wiimote to rumble as well as a beeping sound. This allows for greater interaction

between the controller and robot.

Software

The program which provides the bridge between the Wiimote and the Lego Mindstorms NXT was made

using Microsoft Visual Basic Express 2008. Two open source libraries, Brian Peek’s Wiimote library and

Bram Fokke’s NxtSharp library.

The Wiimote library uses HID profile to connect to the Wiimote. It is able to provide the button states and

accelerometer values of the Wiimote. The NxtSharp library uses serial profile to connect to the Mindstorms

NXT brick. It is able to provide raw data values from sensors connected to the NXT brick and is also able to

send commands to the NXT brick to control the three motor ports. These two libraries were written in C#

and Microsoft Visual C# Express 2008 was used to access the source codes of these libraries.