Abstrakt: |
For most nanopositioning systems, maximizing positioning bandwidth to accurately track periodic and aperiodic reference signals is the primary performance goal. Closed-loop control schemes are employed to overcome the inherent performance limitations such as mechanical resonance, hysteresis and creep. Most reported control schemes are integer-order and combine both damping and tracking actions. In this work, fractional-order controllers from the positive position feedback family namely: the Fractional-Order Integral Resonant Control (FOIRC), the Fractional-Order Positive Position Feedback (FOPPF) controller, the Fractional-Order Positive Velocity and Position Feedback (FOPVPF) controller and the Fractional-Order Positive, Acceleration, Velocity and Position Feedback (FOPAVPF) controller are designed and analysed. Compared with their classical integer-order implementation, the fractional-order damping and tracking controllers furnish additional design (tuning) parameters, facilitating superior closed-loop bandwidth and tracking accuracy. Detailed simulated experiments are performed on recorded frequency-response data to validate the efficacy, stability and robustness of the proposed control schemes. The results show that the fractional-order versions deliver the best overall performance. • Fractional-order control improves nanopositioning systems, enhancing bandwidth and accuracy. • These controllers offer more parameters, boosting achievable bandwidth and accuracy. • Simulations confirm efficacy, stability, and robustness, even with unmodelled effects. • Achievable bandwidth increases by up to 17%, accuracy improves by 35%. • Fractional-order control allows for significant improvements in nanopositioning systems. [ABSTRACT FROM AUTHOR] |