Abstract:In order to study the collision vibration features of sliding bearing under different friction states,the different friction state tests of sliding bearing were conducted on a sliding bearing test bench.The collision vibration signals of sliding bearing were extracted by using the harmonic wavelet packet transform.The variation of collision vibration signals under different friction condition was investigated.The results show that when the sliding bearing is in the boundary friction,the RMS (Root Mean Square) of collision vibration signals is large and is increased as the spindle speed increases.When the sliding bearing is in the mixed friction,the RMS of collision vibration signals is decreased significantly as the spindle speed increases;when the sliding bearing is in the liquid friction,the RMS of collision vibration signals is small and shows a steady upward trend as the spindle speed increases.Therefore the collision vibration signals extracted by harmonic wavelet packet transformation can reflect and monitor the changes of friction states for sliding bearing.