A Dual-Layer Mover Magnetic Levitation Gravity Compensator and Method for Its Rapid Analytical Modeling

To levitate ultraprecision instruments and large-scale aerospace equipment, gravity compensators need to provide greater levitation forces. The realization of such forces is hindered by mechanical structural constraints. Concurrently, the low speed of existing modeling methods makes repetitive calculations for compensators with multiple permanent magnets (PMs) challenging. To address these two challenges, a novel magnetic levitation gravity compensator (MLGC) topology and a rapid modeling method are introduced. For the topology, finite element method (FEM) simulations are used to investigate its performance. For the modeling method, the magnetic field strength (MFS) contributions from PMs at various positions relative to the target are initially assessed. The computation process is subsequently accelerated by limiting the number of PMs considered. In addition, various tradeoffs between speed and precision are evaluated. Ultimately, a prototype is fabricated and subjected to experiments to validate the new topology and modeling method. According to the simulation results, the new topology can effectively increase the achievable levitation force to 14180.84 N without being limited by mechanical structural constraints. In addition, a stiffness of 15.88 N/mm is obtained. Moreover, the novel modeling method significantly reduces the calculation time, with only minor decreases in accuracy. Even the maximum errors are merely 1.33% and 1.23%. The calculation time is reduced by 52.18% and 86.66%. Finally, the topology's performance and the modeling method's effectiveness are validated experimentally.