Dynamical measurements of ship crane load pendulation

Logistics operations such as ship-to-ship cargo transfer on the high seas can be impaired by dangerous crane load oscillations induced by the prevailing sea state. In efforts to measure and characterize the ship and crane load motions for potential control algorithm identification, a system of fiber optic (FO) high-performance, low-frequency accelerometers and an optical radar are used. Data from these subsystems are concatenated, controlled, and analyzed in the LabVIEW virtual instrument environment. A 1:24 scale model test of the cargo transfer scenario was conducted, and some results from a preliminary (dry) test are presented in this work. Results indicate the existence of relatively long transient dynamics modes and complex chaotic behavior in a region near primary crane load swing resonance, Brief mention is also given of a phase-sensitive detection technique that can be used to analyze the data