I am looking for open source implementations of an EKF for 6D pose estimation (Inertial Navigation System) using at minimum an IMU (accelerometer, gyroscope) + absolute position (or pose) sensor.
This seems to be such a recurring and important problem in robotics that I am surprised I cannot find a few reference implementations. Does everyone just quickly hack together his own EKF and move on to more interesting things? Is that not rather error-prone?
I would ideally like a well-tested implementation that can serve as a reference for fair evaluation of possible improvements.