Friction compensation for an industrial hydraulic robot

Dept. of Autom. Control, Los Andes Univ., Merida
IEEE control systems (Impact Factor: 3.39). 03/1999; DOI: 10.1109/37.745763
Source: IEEE Xplore

ABSTRACT A model based friction compensation scheme using a novel dynamical
friction model was implemented on an industrial Schilling Titan II
hydraulic robot. Off-line estimation of parameters was carried out,
using the results of two kinds of experiments. These experiments were
done independently at each joint. A nonlinear PI type controller was
used in the inner torque loop to improve its performance. The complete
control scheme has shown to substantially improve the position precision
in regulation and tracking. Higher precision applications can be
performed by the hydraulic robot with this controller

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