Grant: Idea to Innovation

Many processes in advanced manufacturing applications, petrochemical industries, aerospace, robotics and others have nonlinear parameters. These parameters result in nonlinear dynamics that make the precise control of these processes very challenging. The degree of nonlinearity on these parameters can be low, ranging to severe, where nonlinear control is desirable for good control performance. Existing nonlinear controllers are very complex, making them non-generic and narrow in application. Consequently, there is a significant requirement for a robust and effective controller that can provide suitable control for challenging nonlinear plants. A new nonlinear control methodology has been formulated that is simple, effective and generic with good control performance for a wide range of industrial process nonlinearities. The new methodology is termed Multi-Dimensional Nonlinear Control (MDNC). The MDNC strategy is designed to handle single and multivariable plants with nonlinearities associated with process gain, time constants deadtime and deadzone, as well as time varying behaviour. A unique feature of MDNC is that the methodology can be used with other (superimposed on) advanced control strategies in order to improve their performance without changing the original structure of these advanced controllers. This is a powerful and unique mechanism as it makes the procedure for enhancing or upgrading existing controllers to control nonlinear systems simple, in comparison to other approaches that are generally specific. The application of MDNC potentially is very wide and has been successfully applied on an industrial plastic injection molding machine (IMM), where several highly nonlinear processes exist. The MDNC strategy was demonstrated practically on controlling high speed injection and was able to track complex nonlinear speed setpoint trajectories. Other areas of application include any manufacturing process, robotics, aerospace and other nonlinear processes. Recently, a US patent was filed on this new scheme. The project aims at the technology transfer of the MDNC to industrial manufacturers of IMMs and associated equipment.