Final team documentation

Our final machine was essentially a successful failure. The machine itself did exactly what it was supposed to by conveying the balls to the top of the slot, dropping them onto the chute, and allowing them to roll to the other side. Unfortunately, the basic strategy behind all of this was very defeat able by our opponents. All that our opponent had to do was simply block the path at the end of our chute, which all of the arm based slot-bots did.

Basically, our machine was made up of a belt with scoops attached to it that wrapped around two pulleys at each end of 2 ft brackets. One of the pulleys was driven by a planetary gear box, while the other pulley rotated freely. The box that held the conveyor in place had a slot at the bottom that constrained the conveyor, and allowed it to move up and down. Another planetary gear box mounted on the outside of the box was connected to a rack and pinion system which was attached to the conveyor, which then drove the conveyor up and down. Inside the box, there were plates that held the balls in place on the scoops after they left the slot, as well as constrain the conveyor from pivoting. The chute allowed the scoops to move through it, while still catching the ping pong balls.

Above is a picture of the box that sat on the top of the arena. The sides of the box helped support the weight of the conveyor belt and provided a surface to mount the z-axis motor to. You can see in the picture the top pulley of the conveyor belt and motor that turned the conveyor belt. Also in the picture is the gear that raised and lowered the conveyor belt into the slot.

The design and manufacturing of our machine eventually all worked out, but not as we expected it to happen. We had many more variables involved in our machine than expected, and at times it seemed to be much more complex than we had planned. For example, the box at the top of the slot which was holding our conveyor required many more components than originally expected. We had to have components that could constrain the conveyor in place, as well as components that would keep the ball from falling off the scoop while it was turning over the top. Even with the unexpected issues, we were able to get our machine to function as intended.

Below is a picture of the box after some of the unexpected components were added. You can see in the box a wheel that is held in place by two metal brackets and an axle. This additional wheel was added to help the conveyor to easily move laterally in the slot as well as to prevent the weight of the planetary motor and the motor bracket from dragging the conveyor belt too far down into the slot, or pulling the rack away from its associated gear.

This last photo is a picture of our conveyor belt. In the picture you can see the two support brackets that we wrapped in black electrical tape to keep the rough edges of the aluminum from scratching the slot. The pulley at the top is driven by the planetary motor, which then drives the belt. The scoops are fastened to the belt using epoxy and red electrical tape.