Cold start control of industrial printers

The paper focuses on maximizing the economic performance (throughput) of industrial printers under changing operating conditions. An interesting problem for these printers is the cold start, when printing components have to be heated up as soon as possible to have minimum delay for the first print. To maximize the throughput of these machines, it is important to determine an optimal heating strategy, as temperature considerably influences the print quality. Also when switching between different media types, the print quality has to be guaranteed. A input dependent model of the system can catch the dynamics for the entire process. A control approach is proposed to maximize the throughput while guaranteeing quality of the system. It is based on a nonlinear dynamic input-dependent predictive controller. MPC is a good choice to control the behavior of printers, because it can deal in an optimal way with hard constraints and available information of the predicted print queue. Simulation examples show the effectiveness of the proposed approach in the presence of variation in the constraints and in the print queue.