Cockpit instrument giving sailing boat speed w.r.t. wind - uses mathematical combination of damped readings of speed and angle

摘要

The method and device are for measuring the speed of a sailing boat w.r.t. the wind and involve measurement if wind speed and direction relative to the boat, the speed of the boat in its axial direction relative to the water, and the perpendicular drift speed. They enable a direct accurate indication of speed components in the direction of the wind for different angles between boat and wind direction over a large range of angles. This enables optimal sail settings to be made for crossing the wind direction. Damped instantaneous measurement values are mathematically combined following sampling periodically according to sampling theorem constraints. The boat speed relative to true wind components and the boat axis to wind direction angle are derived and combined for each instant into a speed-angle control function.