pic: Team 488 Presents X

[Madison]

Team 488 is proud to unveil X, its entry into the 2005 FIRST Robotics Competition. X takes the old adage of "KISS" to the next level by marrying simple mechanisms and components in quantity to produce outstanding results.

We decided early in the season that we were afraid, frankly, of the complexity of a device that could acquire, store and score multiple tetras at a given time. The effort required seemed to have very little payoff with respect to scoring and machine reliability. Instead, we thought about constructing a simple, reliable device that could grab and score a single tetra at a time and felt satisfied that such a strategy would perform well at the Pacific Northwest Regional.

As it turns out, building two of something really isn't that much more difficult than building one. I invite you to meet Bonnie and Clyde.

Each arm rotates approximately 60* via the actuation of a single 1.5" bore, 11' stroke piston in less than 2 seconds. The two positions we provided for line the arm up perfectly for acquiring tetras from both the human player and the automatic loading zone as well as scoring tetras on the outside and center goals.

The arms are two-segment, telescoping devices driven by a chain coupled directly to the output of the provided window motors. To reach its full length, each arm takes approximately 6 seconds. The spring loaded tetra grabbing and release mechanism attached to each arm offers an addition 24" of reach and ensures that we do not need to telescope to score on any but the center goal, making scoring fast and efficient.

When lowered to their horizontal position and fully extended, the overall length of our robot shifts from 38" at the start of the match to an astounding 212" (17' 8"). This makes the robot effective in defense as well as offense, though we understand the limitations on our defensive effectiveness as a result of the immensity of the structure in that position.

We store air in two Clippard storage tanks and can actuate each arm to grab and score a tetra simultaneously. An onboard compressor quickly replenishes the air supply.

The drivetrain uses the provided KitBot gearbox with a modified chain reduction as its final stage. We are using 6 Skyway Wheelchair wheels taken down to 7.5" diameter with a slick tread for maneuverability. Our center wheels are lowered 3/16" from the outside wheels. Our top speed, under load, is approximately 7'/sec.

The students had some doubts about the robot and its design after seeing many of the area teams field completed robots at a Saturday scrimmage. After a long night Monday, they were exceptionally proud of the work they'd done when "X" came to life for the first time. This machine is, without a doubt, the best robot I have ever worked on in my seven years' involvement.

Your comments and questions are welcome and appreciated.