A Validated Model for Design and Evaluation of Control Architectures for a Continuous Tablet Compaction Process

• Main Authors: Fernando Nunes de Barros, Aparajith Bhaskar, Ravendra Singh
• Format: Article
• Language: English
• Published: MDPI AG 2017-12-01
• Series: Processes
• Subjects: tablet press; nonlinear model; model predictive control; continuous manufacturing; quality by control; critical quality attributes
• Online Access: https://www.mdpi.com/2227-9717/5/4/76

The systematic design of an advanced and efficient control strategy for controlling critical quality attributes of the tablet compaction operation is necessary to increase the robustness of a continuous pharmaceutical manufacturing process and for real time release. A process model plays a very important role to design, evaluate and tune the control system. However, much less attention has been made to develop a validated control relevant model for tablet compaction process that can be systematically applied for design, evaluation, tuning and thereby implementation of the control system. In this work, a dynamic tablet compaction model capable of predicting linear and nonlinear process responses has been successfully developed and validated. The nonlinear model is based on a series of transfer functions and static polynomial models. The model has been applied for control system design, tuning and evaluation and thereby facilitate the control system implementation into the pilot-plant with less time and resources. The best performing control algorithm was used in the implementation and evaluation of different strategies for control of tablet weight and breaking force. A characterization of the evaluated control strategies has been presented and can serve as a guideline for the selection of the adequate control strategy for a given tablet compaction setup. A strategy based on a multiple input multiple output (MIMO) model predictive controller (MPC), developed using the simulation environment, has been implemented in a tablet press unit, verifying the relevance of the simulation tool.