Shaping Container Motion for Multimode and Robust Slosh Suppression

The majority of slosh-control techniques have required feedback control to suppress liquid oscillations induced by container motion. Input shaping is an alternative method for generating motion commands that reduce slosh without the need for sensors. This paper provides a rigorous theoretical process for designing multimode and robust input shapers for slosh suppression. Furthermore, it demonstrates that the input-shaping method is more effective than traditional command-smoothing methods. This paper describes the design of four different input shapers that reduce multiple slosh frequencies and have robustness to frequency changes that can occur in containers of sloshing liquids. The performance of the input shapers is then compared with typical unshaped and smooth commands. Experimental results show that input shaping can robustly reduce slosh amplitude over a range of liquid depths.