Mechanical Design:
The Mast:
comes out the top of the robot, and unfolds from five feet at the start of a match to almost nine feet (during the 20 second autonomous period) so it can score on any elevation. It is made of 45x90mm Bosch extruded aluminum, milled out to save weight.

The Carriage:
The carriage consists of a large chunk of extruded aluminum, with two motors (one driving a pinion to move the carriage up and down, the other pushing a lead screw to open and close the grabber.

The Drive System:
The drive system of the '07 bot consisted of 4 front-mounted drive wheels (2 per side) and two rear mounted casters. The drive wheels were powered by two CIM motors, with no gear reduction, and no transmission.

Electronics:
1x IFI Microcontroller
1x large power distribution block
1x small power distribution block
3x Victor speed controllers
1x Spike
Assorted fuses

Game Strategy:
In our initial design, we stressed the ability to reach all three levels of racks, and high maneuverability. In the end, we accomplished this, but did not take into effect how important speed would be in the final game. Another thing we failed to think about was that although the higher legs are harder to get to, they are still worth the same amount of points, making them really not worth the effort.

Performance:
The performance in the competition was exactly as we had expected, the four drive wheels arranged around the mast gave us huge maneuverability, and made us a formidable defensive robot. However, the carriage moved up and down the mast painfully slow, and the casters made it easy to push us around. The mast also made us top heavy, and easy to knock over.

What we learned:
Speed is a key factor, especially in a two-minute game.

Tighten bolts

Strategize first

Plan your work, and work your plan
-Andree

Mechanical Design:

The Frame:
Pretty simple, .75 x 1.5" hollow aluminum, welded together.

The Drive System:
The drive system of the '08 practice bot consists of six driven wheels, three on each side. Each side is powered by two CIM motors, running through Andy Mark SuperShifter two-speed transmissions.

Strategy:
Last year, we learned that no matter how hard it is to build something, it's much easier to build something a second time. We are making this chassis so that we can make one again during build season twice as fast, and probably better. Additionally, once we have shipped off the robot, this one will be used for driving practice until the competition.

What we learned:
Offset center wheels need to be offset more than 1/16"

Transmissions are heavy

Planning the design fully before building makes everything easier

Mechanical Design:
The Tower:
comes out the top of the robot, and is made of .75" x 1.5" square aluminum tubing. It is held to the frame by twelve .25" bolts, making it completely removable in under 5 minutes

The Arm:
The arm is made of very sturdy 1.5" diameter hollow aluminum tubing. Inside is a 10" throw, .75" diameter Bimba pneumatic cylinder. The cylinder pulls on two sets of fiberglass rods and contracts a loop that hangs out the front of the robot.

The Drive System:
The drive system of the '08 bot consisted of 6 powered wheels, three on each side, driven by four CIM motors, going through two speed AndyMark Supershifters.

Electronics:
1x IFI Microcontroller
1x large power distribution block
5x Victor speed controllers
4x Spike
1x Custom backup battery charging circuit
Assorted fuses

Game Strategy:
We spent much longer this year on game strategy than last year, and decided that with three robots and two balls per team, there would be no consistency in what our robot had to do. So, we went for a design that allowed us to hurdle, carry, herd, and place/remove the ball.

Performance:
Beautiful, we hope...

What we learned:
Pnuematics are powerful, and more reliable than motors.