Investigation of a Linear, Two-Degree-of-Freedom Simulation of the XR-3 Captured Air Bubble (CAB) Craft in the Frequency Domain.
Abstract
A simplified two-degree-of-freedom simulation in heave and pitch of the XR-3 Captured Air Bubble (CAB) testcraft is developed first in a non-linear form and is subsequently linearized about the steady-state operating point. The model is validated against the six-degree-of-freedom XR-3 Loads and Motions program in the time domain; the linear system is then transformed into the frequency domain by complex matrix inversion. A comparison is made between the linear system frequency response predicted by the two-degree-of-freedom model and that of the Loads and Motions program, as well as actual testcraft data, reduced to the frequency domain by a Fast Fourier Transform (FFT) technique. This comparison of frequency response curves highlights a non-linear mode of CAB craft behavior of possible interest to habitability and seaworthiness studies. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1977
- Accession Number
- ADA044325
Entities
People
- Lewis Frank Mcintyre
Organizations
- Naval Postgraduate School