article · German
Analyse von natürlichem Modellseegang
A 1968 journal article (Schiffstechnik, Vol. 15, No. 75) by Dipl.-Ing. S. Kastner describing the design and construction of a special electro-mechanical analog analyzer for real-time spectral analysis of natural sea states during ship model stability tests. The instrument uses sine-cosine potentiometers driven by a synchronous motor to compute Fourier coefficients in the 0.25–1.5 Hz range (wavelengths 0.7–25 m), with 40 RC-integrator storage channels (τ = 1200 s, 4-minute integration cycles); the paper compares this approach to analog-computer filter circuits, digital methods, and drum-scanning techniques.
sea-state spectrum analysiselectro-mechanical analog analyzerFourier analysisship model testing