Purpose This study tackles two challenges in aluminum-magnesium (Al-Mg) alloy rolling – control delay from measurement hysteresis and strong nonlinearity with limited passband precision – by proposing a predictive control scheme that couples an optimized starting-point combinatorial discrete grey model (OSCDGM), with an improved PID neural network (IPIDNN). Design/methodology/approach An OSCDGM framework based on an Optimized Starting-Point Discrete Grey Model (OSDGM) uses change-point-driven updating with tail correction and Fourier-series residual compensation to achieve high-accuracy real-time prediction of inter-stand thickness. Predicted and measured values are fused to drive online learning of an IPIDNN controller, which augments a PID neural network through variable-speed integration, incomplete differentiation and tanh-based nonlinear mapping to enhance tracking, passband control and dynamic response. Findings Field experiments show that OSCDGM reduces prediction errors by 36–42% relative to Even Grey Model (EGM), Discrete Grey Model (DGM) and Support Vector Machine (SVM). IPIDNN shortens settling time by 79–88% compared with Back Propagation-Proportional-Integral-Derivative (BP-PID), PID Neural Network (PIDNN) and model predictive control. Under disturbances and noise, the standard deviation of control deviation is reduced by 68% versus conventional PID, with fluctuations confined within ±3s and thickness accuracy improved by about 27% in production. Research limitations/implications Application to full-pass rolling of AZ31B alloy verifies engineering applicability and demonstrates markedly improved thickness consistency and stability, while highlighting the need to assess generalization to alloys with different plastic properties. Originality/value The study establishes an integrated architecture combining high-precision dynamic prediction with structurally enhanced neural-network-based control, providing a paradigm for intelligent control of high-precision metal rolling with significant time delays and nonlinearity.
Wang et al. (Fri,) studied this question.