Active stabilization of lateral and rotary slosh in cylindrical tanks

Sloshing of liquid in a tank is important in several areas including launch vehicles carrying liquid fuel in space application, ships, liquid cargo carriages, molten metal handling systems, industrial liquid packaging systems and so on. Theoretically control of sloshing liquid in a tank offers a challenging problem of control of nonlinear systems governed by partial differential equations. This paper develops slosh stabilizing controllers based on two nonlinear lateral sloshing phenomena in cylindrical tanks. Two slosh models, first a nonlinear multiple pendulae equivalent of lateral sloshing effects and next a nonlinear rotary slosh model valid near resonance, are considered. Theoretically asymptotic stability of the equilibrium with the proposed controllers is established using LaSalle's invariance principle. Simulation results demonstrate the effectiveness of controller in stabilizing slosh effect. Implementation of the proposed control is carried out experimentally using force feedback from the container in a novel way. Experimental results further demonstrate the effectiveness in suppressing the slosh.