Design

We built ChanaChai to be an all-round robot. It had speed, accuracy, versatility, robustness and above all, the ability to sort the blocks. Our original goal was to go around the table, pick up as many blocks as we can and sort them into different compartments.The robot would then give the opponents negative points by traveling to the opponent's jail and release professor and student blocks.

Unfortunately we didn't have enough time to tune ChanaChai to its optimal performance. By the time the contest came we had to opt for a pre-programmed robot. We used bump sensors to navigate rather than line-following. The path was simplified to orientation, a fast run straight down the table to the opponent's jail, drop off students and professors and return to our side of the table at the end of the 60 seconds.

Programming

Click here to access our javadoc files.

Mechanics

Drivetrain
	Four Polariod motors were used per drivetrain. A 27:1 gear ratio to achieve the speed we wanted (the robot got from one end of the contest table to the other in just over 2 seconds!). Normal steering was used. Each front wheel was controlled using a servo mounted on a Lego turntable.

Sucker
	An invention inspired by last year's robots. The rollers catch onto the block and topple it so that it can be moved upwards by the conveyor system. The only problem we had with this mechanism is that it couldn't cope with too many blocks at the same time.

Conveyor
	Our conveyor system. This picks up the block from the contest table, raise it to a certain height and feed it to the sorting unit. The unit consists of a vertically placed conveyor belt and a series of wheels accurately spaced so that a block would fit in between while being lifted up from the table.

Sorter
	Light-activated sensor was used to distinguish the block colors. A sorter is a motor-driven Lego piece which "kicks" hacker blocks into a compartment. The yellow Lego piece in this picture kicks the block such that it falls into a compartment at the bottom.

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