May 19, 2011

IMU and GPS Integration with Elphel Cameras

by Andrey Filippov

CAD rendering of the Analog Devices ADIS-16375 Inertial Sensor, 103695 interface board and 103696 serial GPS adapter board attached to the top cover of NC353L camera

For almost 3 years we had a possibility to geo-tag the images and video using external GPS and optional accelerometer/compass module that can be mounted inside the camera. Information from the both sensors is included in the Exif headers of the images and video frames. The raw magnetometer and accelerometer data stored at the image frame rate has limited value,  it needs to be sampled and processed at high rate to be useful for the orientation tracking , and for tracking position it has to be combined with the GPS measurements.

We had developed the software to receive positional data from either  Garmin GPS18x (that can be attached directly to the USB port of the camera) or a standard NMEA 0183 compatible device using USB-to-serial adapter. In the last case it may need a separate power supply or a special (or modified) USB adapter that can provide power to the GPS unit from the USB bus. (more…)