Identification of Flexible Joint Robot Inertia Matrix Using Frequency Response Analysis

Abstract

This paper introduces a novel method for identifying the inertia matrix of multi-DOF Flexible Joint Robots (FJR) that is robust to nonlinearity. By leveraging resonance and anti-resonance frequencies in the Frequency Response Functions (FRF), our approach overcomes limitations of conventional methods prone to mechanical nonlinearities, offering more accurate robot control. Additionally, it highlights the benefits of frequency domain system identification, including nonlinear robustness and flexible joint decomposition into motor and load components. A novel sequential excitation algorithm is proposed for inertia matrix determination, validated through simulation and experiment.