Final Team Documentation

Our final design consisted of four main components. First the main component, the harvester. The harvester ended up similarly to how we originally designed. We changed from 3 paddles to 2 paddles after testing the sketch model. Our final model finished with 2 paddles. These paddles were made of acrylic and delrin spacers, with aluminum axles connecting the harvester to a planetary motor. The acrylic and delrin were laser cut and the aluminum was turned down on the lathe. The harvester can be run forwards or backwards. The harvester design and manufacturing went well with minor issues with the axles. In the end the harvester performed well in competition and was getting enough power to successfully pull in balls.

Second is the frame, made out of 12"x12" aluminum plate and the 1"x2" aluminum. The 1"x2" aluminum was shaped using the bandsaw. The aluminum plate was cut on the water jet and the waterjet moved it during cutting, which changed most of our holes by 1/8". While putting our machine together we had to file and drill these holes to size so everything would fit. We added the slanted bottom from our original design and it worked well with the trap door. This part was also waterjet, and turned out well. One big issue we had with machine performance was the bent metal at the front which was not quite at the angle we would have liked due to the shift during the water jet. The frame connects all of the other components. The frame is almost exactly how we originally thought it would be.

Third is the trap door, which in our original design and sketch model we were unsure how the trap door would work. In the end we decided the put a roughly 3" diameter hole in the back of the frame and attach a laser cut piece of delrin to a motor and rotate it about the bottom to let balls drop through the bottom. Attaching this to the bottom of the machine was a little bit of an issue, but only a small one, especially in comparison to the other issues we had with holes matching up.

Last are the tracks and drivetrain, which we originally designed so we would have a 0 turning radius. We waterjet aluminum for the tracks to screw into the frame on both sides. Attaching the tracks was not a problem, but in practice the tracks would not stay on well when turning too much. Also, turning did not become much of a problem for us, due to the fact that the motors did not apply enough power for our machine to move very quickly even at high gear ratios.

Overall, our machines design and manufacturing went well, and we had a great start with a functional sketch model, and from then on out we did not have to change much from our design model to our final robot. This was very helpful for our team, so we only had to apply minor changes to our original design.