Vessel Motion Monitoring System: A Prototype System to Monitor Slamming Severity in High Speed Craft And Its Utility to the USCG Fleet

摘要

USCG vessels operating at high speeds are subject to severe slamming and other dynamic forces; installation of shock-mitigating seats have isolated vessel operators from these severe forces. Lessened sensitivity to forces has allowed vessels to operate at higher velocities in larger sea states and therefore at higher structural loading conditions. An undergraduate project in Mechanical Engineering pursued the design, build and test of a Vessel Motion Monitoring System (VMMS) to measure, record and analyze vessel acceleration data and provide alarms to operators when structural or human factors thresholds were exceeded. Given the short duration and stochastic nature of the most extreme accelerations, a methodology utilizing an acceleration metric of the average of the highest 10% of the positive peaks in the acceleration data, A1/10, was formulated and validated against actual data collected from a 45' USCG RB-M. A recommended set of system requirements needed for an equivalent system from the commercial sector are defined and preliminary threshold values for an alarm system are proposed. The results of the project validated the described methodology and indicate that the installation of VMMS's across the USCG small boat fleet is likely to improve asset lifecycle predictions and decrease the prevalence of long term injury to vessel operators.