Distance estimation and direction finding using I2C protocol for an auto-navigation platform

This paper presents an auto navigation platform in Arduino which uses the i2c protocol to interface a digital compass and a rotation encoder to calculate distance travelled and direction with respect to the Earth's magnetic field. The digital compass IC used here is the HMC6352, while the rotation encoder is designed with the help of a MOC7811 coupler IC. The compass contains complete 2-axis sensors, analog, and digital electronics and also contains all the firmware for heading computation and calibration. The rotation encoder is an electromechanical device which obtains the angular position of the motor shaft it is connected to and then converts this position into some analog or digital value. This is mostly done using optoelectronic sensors which provide electric pulses in response to some stimulus. We use this property of the device to accurately guide our auto navigated device to pre-determined distances.