File:TESTING STABILITY WITHOUT PENDULUMS- A FEASIBILITY ANALYSIS (IA testingstability1094559662).pdf

Current International Maritime Organization (IMO) and U.S. Coast Guard regulations require inclining tests of vessels to use three heel-measuring devices, one of which must be a pendulum. This is a problem since pendulums are required to be at least 10 feet in height and newer vessel designs are constrained by overhead clearance and deck space. To investigate this problem, this thesis examines five different stability test results that were submitted to the U.S. Coast Guard Marine Safety Center (MSC). The author identified and inputted random error into the independent variables used to calculate each vessel’s metacentric height (GM). The independent variables were then used in a Design of Experiment (DOE) to examine which factors had the strongest effect on GM. Of the factors analyzed, the device used to measure heel angle proved to be the most significant. The author then constructed three different miniature models to conduct inclining experiments in a controlled environment. The heel-measuring devices used during these experiments were a smartphone and pendulum. In all three miniature model experiments, the smartphone demonstrated better precision over the pendulum. This thesis recommends keeping current standards and regulations intact until further data and research are gathered.

Subjects: incline experiment; stability test; metacentric height; pendulum; digital inclinometer