Orientation modulated piezoelectric patches for active vibration reduction of thick plates using a singular value decomposition-based optimization

Active vibration reduction in thick plates remains a significant challenge in structural control. This study proposes a novel method for optimizing the orientation of piezoelectric sensor/actuator pairs to enhance vibration suppression. The dynamics of thick plates are modeled using Mindlin plate theory and solved using the finite difference method. The optimization problem is addressed using a binary-coded genetic algorithm, with Singular Value Decomposition (SVD) of the modified control matrix as the objective function. Numerical simulations on a cantilever thick plate demonstrate that optimizing both patch orientation and location significantly improves vibration reduction. The proposed method achieves an average closed-loop dB gain reduction of up to 25.85% compared to location-only optimization and substantially outperforms both random and thin-plate-based configurations. These results highlight that alignment of piezoelectric patches with local strain directions is critical for maximizing electromechanical coupling and control effectiveness. The present framework offers a robust and efficient approach for designing high-performance active vibration control systems in thick plate structures, highlighting the combined importance of spatial placement and directional alignment for achieving superior performance and resource efficiency.