Adaptive tuning of heave filter in motion sensor

This paper describes the problem of accurate estimation of heave motion based on accelerometer measurements and the development of an adaptive heave filter algorithm. This algorithm characterizes the mean wave height, dominating wave frequency, sensor noise, bias, and misalignment of the accelerometers to determine the sea state or sea conditions. By classifying the internal and external variables, the algorithm changes the filter settings accordingly. This novel technique has been implemented in the Seatex Motion Reference Unit (MRU), and is a step towards making the MRU less dependent on the application and easier to use