delay independent control

Design of Delay Independent State Feedback Control for Roll-to-Roll Printing Applications

Control of print quality (registration) in roll-to-roll (R2R) printing is challenging because of the presence of transport delays involved in the printing process. In this work we present a delay-independent state feedback control design to stabilize a R2R printing press by considering all the significant dynamics involved in the printing process. State feedback control design using past state measurements (controllers with memory) are discussed first. Since controllers with memory are less desirable in industrial applications, we investigate and discuss the feasibility of designing a simple, memoryless, delay-independent state feedback controller for printing applications. The feasibility is shown by the use of a control design procedure that exploits the structure information in the system matrix to find a stabilizing controller. The design procedure is also extended to other common industrial R2R control strategies, such as decentralized control and state feedback with integral action for R2R printing applications.

Decentralized Control of Print Registration in Roll-to-Roll Printing Presses

Roll-to-roll (R2R) manufacturing is a type of continuous manufacturing process extensively used to produce a wide variety of consumer products, such as plastics, paper, films, non-wovens, textile, etc. Recent advances in nanotechnology and material science have enabled the possibility of manufacturing electronics on a flexible substrate using R2R printing techniques. Even though the feasibility of printing electronics on flexible substrates has been extensively studied, continuous printing on a moving substrate using R2R techniques has not been adequately investigated. To facilitate progress towards high precision R2R printing, a systematic investigation of the various aspects that affect print quality and ways in which those can be influenced by different control configurations facilitated by choice and location of various components of the print section is necessary.