Control of liquid handling robotic systems: A feed-forward approach to suppress sloshing

This paper presents a feed-forward approach to reduce sloshing dynamics in liquid handling robotic systems. According to our solution, the dynamics of a liquid into an open vessel manipulated by a robot can be described by means of a spherical pendulum mechanical model. By doing this, the sloshing problem can be addressed as a vibration suppression problem for a second order system. More in details, the pendulum model is utilized to tune an exponential filter which shapes the reference trajectory for the robot, thus achieving a sloshing-free motion of the liquid inside the vessel.

I. Introduction

The current industrial scenario is becoming more and more competitive and, as a consequence, modern manufacturing is always more strict with regard to performances and dependability. In this respect, industrial automation is playing a key role as a powerful means to optimize manufacturing processes and maximize their efficiency and flexibility of production lines. For this reason, industrial robotics is pervading many diverse industrial fields to overcome the severe and unacceptable limitations that are due to the use of rigid automation systems. A particularly interesting and promising case is the use of industrial robots in the food processing industry to increase flexibility, performances and system dependability. In this framework, not only robots are utilized to perform standard heavy-duty tasks, but also to accomplish tasks which are traditionally executed by human operators or by means of process control systems (see [1]).