Air-bearing systems are extensively applied in ultra-precision machining owing to their non-contact operation and nanometer-scale positioning accuracy. However, the compressibility of the air film and inherent low damping compromise system stability under dynamic disturbances. To address these challenges, this paper presents a fuzzy sliding mode-based hybrid control algorithm. The architecture integrates proportional-integral-derivative (PID) control, velocity/acceleration feedforward (FF), and fuzzy sliding mode control (FSMC), where fuzzy logic is employed to suppress sliding mode chattering. Simulations and experiments were performed on low- and high-frequency testbeds. The air-bearing testbed achieved a rise time of 8 ms and an overshoot of 0.29%, while the FTS system achieved a rise time of 1 ms and an overshoot of 3.08%. The measured closed-loop −3 dB bandwidth of the FTS system was approximately 500 Hz. In micro-pit machining, the arithmetic mean surface height Sa decreased from 10.4 nm with PID-FF to 7.1 nm with PID-FF-FSMC, corresponding to a reduction of 31.73%.
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A Fuzzy Sliding Mode-Based Hybrid Control Algorithm for Air-Bearing Machining Systems
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Received: 10 September 2026 | Revised: 15 October 2026 | Accepted: 20 October 2026
Abstract
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