We successfully connected the BNO085 IMU sensor to the Arduino Uno over I2C. 

Minimal RAM on the Uno means we couldn't use Adafruit's BNO08x library. Luckily Sparkfun's BNO085 library works just fine. We were able to get real-time readings of rotation vector data with some built-in example sketches. 

Once we mount the BNO085 to the unicycle body, we can continue calibrating for the upright position. TBD if control of two IMUs oriented on each wheel's axis of rotation is necessary/plausible.