Erschienen in:
Fractal and Fractional, 7 (2023) 1, Seite 52
Sprache:
Englisch
DOI:
10.3390/fractalfract7010052
ISSN:
2504-3110
Entstehung:
Anmerkungen:
Beschreibung:
Impedance control is widely applied in contact force control for robot manipulators. The traditional impedance model is linear, and has limitations in describing the actual impedance force. In addition, time-varying and dynamic coupling characteristics pose critical challenges to high-speed and high-precision impedance control. In this paper, a fractional order impedance controller (FOIC) is proposed for industrial robot manipulator control and a systematic FOIC parameters tuning strategy based on frequency-domain specifications is presented. In order to improve performance under dynamic disturbances, a dynamic feedforward-based fractional order impedance controller (DFF-FOIC) is further developed. The robot manipulator dynamics are investigated and the effectiveness of the DFF-FOIC is illustrated by simulation. Then, the DFF-FOIC is applied on a physical robot manipulator prototype. Our step force tracking test results show that the proposed FOIC has better control performance than an integer order impedance controller (IOIC), achieving a better step response with lower overshoot, less settling time, and smaller integral time absolute error (ITAE) than the IOIC under fair comparison conditions.