About the Robot (2010 season)

The 2010 robot, nicknamed Oldsmobile, was designed for versatility. In order to work in all three areas of the field, it is equipped both with a medium-range kicker and a plow. Mekanum wheels allow the robot to move in any direction, at any heading, with any speed (within reason, of course). It also has an arm that will telescope out and grab onto the overhead bar.

The team put quite a bit of work into the kicker. We initially had three design groups, each working with a kicker concept. One of the concepts, storing energy with elastics, was eliminated early. It worked amazingly, but the mechanism wouldn’t fit under the tunnel on the field. The team opted to maintain maneuverability. The other two designs were both longer-lived. One team worked with pneumatics, and another built a rotary kicker. The pneumatic design was promising – small and powerful, but the robot couldn’t supply it with enough air. The rotary kicker was the most promising of the three designs.  It spun a pair of dowels 5” away from a central hub at several hundred RPM. Its speed was variable via joystick. If the kicker spun too fast, then the ball and the kicker would be tangent when they met, so the ball would be given nearly no speed. The ball was thrown much further when it was allowed to enter well into the arc of the kicker. 

The plow was added to allow for finer control of the soccer balls on the field. The kicker was incapable of herding – if it wasn’t spinning, balls would just bounce off. The plow was slightly curved to ensure that balls stayed inside. It was close enough to the outside of the robot that it could push balls over the bump, into the goal.

Mekanum wheels are incredible devices. When both of the wheels on a side spin the same direction, the robot behaves just as it would with normal tires – it moves forwards, backwards, or turns. When the wheels on each side spin in opposite directions, though, magic happens. The robot moves sideways. In our case, magic comes in the form of small angled rollers embedded into the wheel. The wheels are installed so that the rollers of the two wheels on each side are perpendicular. This prevents the robot from rolling along a diagonal.

Our arm took the most design work out of any part. After brainstorming, the people working on arm design broke into four groups, each with an idea. The best design was a pulley-driven telescope. Its two segments allowed for extension up to the bar, bungees reduced motor load during retraction, a thick hook allowed for secure attachment, and a combination of motors, more pulleys, and springs allowed it to collapse into the chassis during the game. It was an amazing sight to see. Unfortunately, its motors weren't strong enough to lift the robot in the time allotted.

Our robot proved powerful and versatile on the field. We didn't place well (due in part to several 2-on-3 matches), but many of our members are now able to drive a Mekanum robot. The robot (particularly its arm) also allowed us to learn more about fabrication.