Design

Our robot was given to us as sponsorship by Robert Sayle, and so we called it Robert. It has high ground clearance, to avoid obstacles, and large wheels to improve speed. These large wheels do, however, produce some reliability issues, as one degree of movement in the motor will cause the robot to go further if it has larger wheels.

The robot would not be stable with just two wheels. Because of this, we need another point of contact with the ground. Many teams use simple, swivelling casters, or wheels without tyres (if you left the rubber tyres on them, then there would be increased friction) as a third point of contact. We tested these, against a ball caster, and found the ball caster increased reliability, which is why we have one on our robot. Our design of ball caster is good because when the robot is travelling forwards, the wheels on the sides spin, and when it turns, the one on top spins.

There are many lines on the mat which contrast in reflectivity with their surrounding area of mat. This is a good opportunity for the use of light sensors, and as they help to improve our robot's reliability, we opted to attach some. The reason we have two instead of one is that with two light sensors, you can "square off" on a section of line. This process involves driving towards the line (not necessarily in a perpendicular direction to it) and ending up perpendicular to it when you get there. It can be very useful, as it can help to reliably get the robot pointing in the same direction each time you run a program.

We also use "squaring off" against the walls of the table as a strategy to align the robot precisely and reliably.

Software

All programs are programmed with the NXT-G software that comes with the NXT "retail version" kit. We use version 1.1 of the software.

Program 1

Robot during Program 1
The robot collecting a carbon dioxide molecule

Missions attempted:

Flood barrier, Carbon sequestration

Total points:

35

Program 2

Robot set up for Program 2
The robot with the levees and a red person

Missions attempted:

Levees, Red people, Retrieve ice buoy, Storm

Total points:

65

Program 3

Robot set up for Program 3
The robot with the house attachment attached, and blue person obscured beneath

Missions attempted:

Blue people, Bicycle, Insulation, Laptop, Open window, Turn off lights, retrieve yellow ball

Total points:

85

Program 4

Robot set up for Program 4
The robot with the alignment and driller attachments

Missions attempted:

Alignment, Raise house, Retrieve ice core driller, Ice core

Total points:

95

Program 5

Robot set up for Program 5
The robot, ready to drag everyhing into the research area

Missions attempted:

Deliver raised ice core driller, White people, Polar bear, Snowmobile, Deliver ice buoy, Yellow ball, Beat the clock

Total points:

120