Dynamics modeling of variable mass systems – a case study of an underwater inertia based propelled glider performance

Underwater gliders are autonomous underwater vehicles that are widely used in oceanography and coastal surveillance due to their low manufacturing costs and long operation time.This paper addresses the development of a dynamical model of such vehicles which are inertia propelled.The dynamical model is based upon the Boltzmann-Hamel equations modified to variable mass and inertia systems.It yields dynamics in a body-fixed frame using non--inertial coordinates.The theoretical development of the vehicle dynamics based upon the modified Boltzmann-Hamel equations is validated by the longitudinal dynamics model of the underwater glider and its performance resulted from the mass change.