15th Triennial World Congress of the International Federation of Automatic Control
  Barcelona, 21–26 July 2002 
LIQUID LEVEL CONTROL OF AUTOMATIC POURING ROBOT BY TWO-DEGREES-OF-FREEDOM CONTROL
Yu Sugimoto*, Ken’ichi Yano and*
Kazuhiko Terashima*
* Dept. of Production Systems Engineering
Toyohashi University of Technology
Hibarigaoka 1-1, Tempaku-cho, Toyohashi, 441-8580 Japan
FAX: +81-532-44-6690
E-mail: {sugimoto, yano, terasima}@procon.tutpse.tut.ac.jp

The purpose of this paper is to provide a method to hold the liquid in a sprue cup into the constant level and to suppress sloshing (liquid vibration). This paper uses tilting type automatic pouring robot. A two-degrees-of-freedom control system is used to control the liquid level. This paper presents a series of models representing each part of the pouring process. Through these models, feedforward input can be achieved. Also, to improve the control, two-degrees-of-freedom-control is applied. Liquid vibration inside a ladle after pouring is suppressed by a controller using the Hybrid Shape Approach. As a result, the liquid level in a sprue cap is held to around the setpoint, and sloshing is suppressed. The validity of the proposed control system is demonstrated through experiments.
Keywords: Level control; Modeling; Feedforward control; Disturbance; Vibration control
Session slot T-Th-E12: Control Applications in Casting Plants/Area code 7b : Mining, Mineral and Metal Processing