Study on the design and structural optimization of excitation blocks for vibrators

The performance of vibrator-based seismic sources is fundamentally constrained by the trade-off between excitation force and motor driving power. To address this challenge, a physics-informed framework for the parametric modeling and multi-objective optimization of annular-sector eccentric blocks is proposed. Firstly, a unified geometric model is established to derive closed-form expressions for mass properties, which are then integrated into a coupled electromechanical dynamic model to link geometric configurations directly with force output and power demand. To enhance computational efficiency, an Extreme-Frequency Substitution Strategy (EFSS) is introduced to reformulate the complex full-band dynamic optimization into a simplified static problem. The primary novelty of this work is the integration of physics-based geometric modeling, electromechanical dynamics, and extreme-frequency optimization within a single analytical framework. Sobol global sensitivity analysis reveals that the outer and inner radii are the dominant design drivers, while thickness and sector angle influence performance primarily through higher-order interactions. Using the NSGA-II algorithm, an optimized design is obtained that achieves a 10.52 % reduction in average peak driving power, a 35.26 % reduction in mass, and a 56.36 % reduction in the moment of inertia, while maintaining the required excitation force. This framework provides a rigorous and energy-efficient methodology for the design of next-generation controlled seismic vibrators.