Intelligent approach for performance improvement of stepper actuator devoted to a medical and clinical application.

Stepper motors are synchronous electric actuators with incremental displacement that can be controlled in open loop in position or speed. Unfortunately, the rotor oscillations that characterize stepper motors are a major handicap that limits the use of this type of actuator in precision industrial applications and especially in biomedical systems. Improving motor drive performance is challenging due to the presence of uncertainty in system parameters and large load variations. To overcome these problems and the shortcomings of conventional control approaches, a new control concept based on fuzzy logic is developed. To this purpose, this paper proposes a fuzzy logic concept (FLC) for damping rotor oscillations of stepper actuator devoted to an Electrical Syringe Pump application. The FLC membership functions and rules are designed with value normalization that allows the developed controller able to be flexible when applied to a wide range of applications. The proposed FLC is numerically validated. Critical testing scenarios are employed including motor inertia variation, supply voltage variation, fluid friction variation and for different loads. Moreover, thanks to its normalized design, the proposed FLC is not limited to the studied biomedical applications, but can be applied to other application systems. [ABSTRACT FROM AUTHOR]