Dynamic modeling and model predictive control of wire mesh tension in multi-wire sawing of natural stone slabs

• Developed a multivariate, coupled dynamic model of the wire-mesh tension system that captures the dominant interaction pathways governing tension fluctuations. • Designed an MPC strategy integrating the model with rolling optimization and dynamic compensation; simulations in MATLAB/Simulink show superior disturbance rejection and dynamic response versus conventional PID. • Experimental sawing on sandstone and white marble validates performance: tension dynamics reduced by 20.2% (sandstone) and 25.4% (white marble), with surface roughness improved by 28.07% and 33.89%, respectively, under comparable conditions. Multi-wire sawing has emerged as a key technology in stone processing, addressing the significant material loss associated with traditional sawing methods and thereby improving the utilization of nonrenewable stone resources. However, a significant challenge in this process is the nonlinear tension fluctuations arising from the inherent heterogeneity of natural stone and the large contact area between the wire and the workpiece. PID control strategy often prove inadequate for managing these dynamics, which can lead to manufacturing defects such as wire breakage, saw marks, and thickness deviation. The novelty of this study lies in the development of a comprehensive multivariate coupled dynamic model of the multi-wire sawing system and the design of a coordinated wire mesh tension control strategy based on Model Predictive Control (MPC). Unlike conventional PID approaches, the proposed MPC framework integrates predictive modeling with rolling optimization and a dynamic compensation mechanism, enabling anticipatory closed-loop tension regulation that explicitly handles system constraints. Comparative simulations evaluate the performance of the proposed MPC strategy against a traditional PID strategy. The results demonstrate that the MPC strategy improves the regulation accuracy of dynamic tension fluctuations by 20.2%. Furthermore, this enhanced stability leads to a significant improvement in surface quality, evidenced by a 33.89% reduction in workpiece surface roughness under identical machining conditions. The proposed method effectively mitigates tension instability in multi-wire sawing, offering a robust approach for improving both material utilization and final product quality.