Electrical Design

The brains consist of 2 PIC32 microcontrollers which communicate with each other via SPI to coordinate his Frank's movement. Informing them are a fleet of sensors: 

• 5 IR line followers to drive straight and execute precision turns

• 1 time of flight distance sensor to detect how far from the wall

• 1 IR signal receiver to detect which IR beacon he is closest to. The signal receiver uses an IR phototransistor to detect the IR beacon. The signal is then passed through multiple gain stages and a high pass filter, removing the DC signal and other unwanted noise. Finally, it is made back into a square wave through the use of a comparator (with hysteresis).

To back up his mighty intellect, Frank interacted with the world in a couple of ways:

• 2 DC motors to power the drivetrain, controlled by a full H-bridge to allow forwards and backwards PWM control.

• 4 Servos– 2 to power the lift mechanism, and 2 to indicate game side. The servos all use an octal buffer to step the PWM signal from 3.3V (coming from the PIC32) to the necessary 5V.