Frequency-Based Identification of the Inertial Parameters of an Industrial Robot

Abstract

Due to disturbances or a lack of excitation during the measurements, conventional identification methods offer solutions with limited precision for the inertial parameters of industrial robots (IR). This paper introduces an approach to increase the rank of the identification matrix through additional equations from the frequency domain. In areas of lower frequencies, the total inertia that is affecting an axis is related to the amplitude of the frequency response of the rotational speed controlled system (RSCS). Another advantage of the presented method is the possible correction of friction effects via the phase information, which enables a higher identification accuracy. The frequency responses are measured during exciting trajectories, which stimulate low frequencies. Thereby, the approach generates additional equations, which enables the identification of more inertial parameters with a higher accuracy. In this paper, the measurement method and the identification algorithm are outlined.