Partial-state feedback control design for liquid container transfer with sloshing suppression

This paper studies the sloshing suppression problem in point-to-point liquid container transfer via a planar Prismatic-Prismatic-Revolute (PPR) robot. The most prominent liquid sloshing modes are modeled using a mechanical analogy based on multiple mass-spring elements. The control inputs are two forces and a torque applied to the prismatic joints and the revolute joint, respectively. The control objective is to control the robot end-effector movement while suppressing the sloshing modes. A Lyapunov-based feedback controller is designed to achieve the control objective. In contrast to the full-state feedback controller we developed in our previous work, the partial-state feedback controller described in this paper does not use slosh state information. The effectiveness of the controller is demonstrated through a simulation example.