Relative position estimator Sample Clauses

Relative position estimator this block is in charge of fusing data available from different sources: i) the ASV’s speed, course angle, and course angle rate broadcast by the ASV; ii) the (delayed) relative position of the ASV with respect to the AUV obtained using an Ultra-Short Baseline (USBL) system installed on-board, iii) the velocity of the AUV with respect to the seabed using a Doppler log (this is the case in shallow water; in deep water, the unit can yield both the velocity with respect to the seabed and to the water), iv) Heading, provided by an Attitude and Heading Reference System (AHRS), and v) surge speed with respect to the water, where the latter is estimated using a quasi- static propulsion model that relates the speed of rotation of the vehicle propellers with the vehicle’s forward speed. Its output consists of the estimate of the relative position of the AUV with respect to the ASV, together with the estimate of the underwater current, both at a sufficiently fast update rate.