Research on Injection Speed Control of Injection Molding Machine based on Iterative Learning Control

This paper introduces a study on controlling the holding pressure stage of an injection molding machine using iterative learning predictive methods. By taking advantage of the known trajectory and repetitive operation data in the injection molding process, a combination of the existing orthogonal parameterized linear time-varying (LTV) modeling method for the holding pressure stage and iterative learning control is adopted. Compared to traditional modeling methods, this approach effectively captures the non-linear and time-varying characteristics of the holding pressure stage in the injection molding process, while reducing the complexity of the model. Additionally, leveraging the repeatability of the injection process, a reference-based batch iterative learning control method based on the LTV model is introduced and its convergence is demonstrated. Experimental results show that this method achieves unbiased tracking of the desired trajectory.