Diseño, implementación y análisis de desempeño de un controlador PID de orden fraccionario (FOPID) aplicado a control embebido de sistemas mecatrónicos

Abstract

The present work is part of the “Hand of Hope” Project, the objective is to design and implement an embedded Fractional Order PID controller (FOPID), applied to the elbow joint speed in a robotic prosthesis. The purpose is to, first, conduct a preliminary research about the feasibility of implementing a FOPID controller in an autonomous embedded system; second, we seek to analyze and compare the performance of classic PID and FOPID controllers. The parameters of a FOPID controller are five: proportional constant (K_P), integral constant (K_I), derivative constant (K_D), integral order (λ) and differentiator order (μ). Finding the optimal set of values for these five parameters is a complex process. As results of this work: seven classic PID controllers and ten FOPID controllers were designed and implemented. The implementation was performed in an embedded platform FPGA-Processor (sbRIO-9651) and in the LabVIEW FPGA & RT language. Finally, experimental evaluation and comparison of controllers were performed, based on the time parameters: settling time, overshoot percentage; and on the error rates: IAE, ITAE, ISE and ITSE. The embedded controllers with the best performance were FOPID Z-N-ISE (Ts = 0.22 s, P.O. = 7.18 %) and PI Chien (Ts = 0.18 s, P.O. = 0 %).