Applied periodic l∞ control: Presenting prototype designs for a real sprayform tooling process

This paper presents the design and implementation of prototype periodic l∞ control systems for governing the temperature profile of a spray-form tooling process that is used in rapid manufacture of tooling. The controllers are based on discrete time varying l∞ theory for periodic/almost periodic linear systems. After a brief description of the process in study and its mathematical modelling, the paper formulates the control problem and investigates its design and characteristic features. The theoretical issues are accompanied with simulation and experimental studies on a real spray-form apparatus. The paper shows that the performance of the proposed controllers is better than previous control designs. This is the first ever application of l∞ control systems for spray-form tooling processes, something that reflect their characterization as prototypes.