Our power is supplied from two 7.2V NiMH rechargeable battery packs. We wanted to drive our motors from a 12V power supply. Similarly, we wanted to power our Arduino and sensors from a 5V power supply. As a result, we connected our batteries in series to provide 14.4V, and used a 12V and 5V regulator for the motors/arduino and sensors, respectively. 

A major part of our strategy to maneuver the course was to use the walls to our advantage. We installed limit switches on the front left, front middle, and front right of our robot. We connected one end of each switch to a digital pin, and the other end to ground. We set the digital pins to input pullup, and when a switch was pressed (a wall was hit), the connection to ground would be complete and the digital pin would read low. This is how we detected when a wall was hit, and how we followed the walls all the way to the ball drop!

To push past the MVP, we wanted to implement line sensing. We used the OPB704WZ line sensors that were available in lab, which consist of a IR Led and Phototransistor. Using the difference in light reflection from the white floor and black tape, we are able to detect when we are on a line. We incorporate an Op-Amp and a potentiometer for tuning, red LED to show when we are on a line, and send V_out to an analog Arduino pin. In total, we implemented 4 line sensors. Unfortunately, we didn't have time to fully implement this in our code for the competition, but it was still fun building the circuit and getting it to work!