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Abstract: The thrust force vector, as controlled by a fixed-grouped thrust system, is essential for trajectory control of tunnel boring machines (TBMs). However, the desired thrust force vector must be decomposed into the output force of each group. Due to the underdetermined properties of the thrust system, there are numerous theoretically possible force combinations. Existing methods to select an optimal solution only consider the force variance between each group while ignoring other constraints, such as the uneven force on a single segment, the excessive hydraulic shock, etc. In this study, we develop a more comprehensive and robust framework for force allocation. First, a novel region-reconfigurable hydraulic system is designed, which enforces consistency among the forces acting on each segment. Then on this basis, for the ramping-up tunneling stage, quadratic programming (QP) is used to optimize force uniformity across the spatial dimension. Compared to the on-site allocation result, the improvement in force uniformity reaches up to 32.89%. Moreover, to address the hydraulic shock caused by excessive adjustment to the force, hydraulic compliance is introduced and optimized together with force uniformity using the non-dominated sorting genetic algorithm II (NSGA-II), which outperforms weighted QP by 1.25×106 in uniformity and 2.86 in compliance. Analyzing performance in the steady tunneling stage, the service life of the components improves significantly. To avoid a non-existent solution for the thrust force vector, a genetic algorithm-based error tolerance method is developed. Therefore, all deviation rectification commands can be answered with a minor compromise of up to 3% in the fitting accuracy of the thrust force vector. In summary, this framework enhances the adaptability and robustness of the force allocation strategy, providing a reliable foundation for TBM trajectory control.