Code and resources for "BalanceBot", an Arduino-powered two-wheel balancing robot.

• Project page: http://rogerignazio.com/projects/balancebot
• Code: https://github.com/rji/balancebot

• Arduino Uno
• 2x Creative Robotics HUB-ee (120:1)
• STMicroelectronics LPY503AL gyro
• Analog Devices ADXL335 accelerometer

Code for this project was developed and tested using the Arduino IDE, version 1.0.4, and the Arduino Uno, Rev 3.

The accuracy of the angle calculation is improved with a complementary filter.

Motor output is calculated using a PID controller. Loop tuning was accomplished using (mostly) the Ziegler-Nichols method, with minor corrections to the values based on observations. To tune, modify the constants kp, ki, and kd.

Colton, Shane. The Balance Filter: A Simple Solution for Integrating Accelerometer and Gyroscope Measurements for a Balancing Platform. Accessed May 2013.

PID Controller. Wikipedia. Accessed May 2013.