A Non-Linear Time Domain Model Of A Free-Fall Oceanographic Vehicle

Free-fall vehicles have gained widespread acceptance as a means by which small scale fluctuations in ocean characteristics such as the temperature and salinity gradients can be accurately profiled. Although these vehicles are used by a large number of programs doing basic and applied research for the Navy, the dynamic characteristics of their free-fall descent are not well understood. This makes the interpretation of some aspects of the recorded data uncertain. Also, there is no framework to guide the preliminary design of new vehicles to optimize their performance. A non-linear time domain anayltical model and an approximately half-scale wind tunnel model have been developed in order to study the vehicle dynamics.