Frictional Running-In Status Identification for Ring-on-Disc Tribosystem by the Visualization of Friction-Induced Attractors

Abstract

This work presents a proposal for frictional running-in status identification of ring-on-disc tribopair using the friction coefficient (COF) time-series and its corresponding attractors. Due to the complexity and nonlinearity of tribosystem, the friction-induced attractors always existed within multi-dimensional phase-spaces. It made the phase-trajectory visualization difficult and inaccurate. Three visualization methods for multi-dimensional data sets were compared and analyzed. Frist, the chaotic characteristics and attractor evolution of the COF signals during the running-in process is investigated based on the attractor visualization. Second, the identification result differences between the time-domain and phase-space domain were measured, which indicated that the running-in status recognition based on friction-induced attractors was more accurate. Finally, the attractor visualization approaches were compared and discussed. Results suggested that the frictional running-in status could be preliminarily identified via radar plots, and then further quantized using RQA measures.

Keywords: Frictional running-in process, Friction-induced attractors, Attractor visualization, Running-in status identification