The dynamics of damage propagation can be modeled as a nonlinear stochastic dynamical state-space process, where system states are not directly accessible and all information about them has to be inferred from the output data. The paper employs an iterative procedure for calculating the Maximum-Likelihood estimate of model parameters, based on the Expectation- Maximization algorithm together with the unscented Kalman filter for estimation of system states. The algorithm has been used to predict the remaining useful life of a single-stage gearbox system.
COBISS.SI-ID: 25338151
A novel statistical approach is developed in order to estimate the time in which an operating gear will achieve the critical stage. The approach relies on measured vibration signals. From these signals features are extracted first and then their evolution over time is predicted. This is done owing to the dynamic model that relates hidden degradation phenomena with measured outputs. The Expectation-Maximization algorithm is used to estimate the parameters of the underlying state-space model on-line. Time to reach safety alarm threshold is determined by estimating the distribution of remaining useful life using the estimated linear model.
COBISS.SI-ID: 23786791
A fault detection algorithm applicable for mechanical drives is developed. Traditionally, fault detection process is done by comparing the observed machine state with a set of historical data represent-ing the fault–free state. However, such historical data are rarely available. We resolved this problem by applying highly sensitive signal processing methods. The obtained results confirmed that the proposed approach was quite effective in for detection of damaged bearings.
COBISS.SI-ID: 25505063
A mobile standalone unit for continuous monitoring of lubricating oil properties has been developed. A user-interface controls the operation of the unit and displays data that are obtained. The operation of the unit was experimentally tested on a laboratory gear test-rig, where contamination of gearbox oil was performed to simulate changes in oil state.
COBISS.SI-ID: 26487591
The invited lecture describes the concept and main functional requirements of the integrated diagnostic system which has been developed during the project. It provides platform for on-line condition monitoring of machines and devices. The underlying technology paves the floor to wider application of condition based maintenance instead of traditional less effective periodic maintenance.
COBISS.SI-ID: 10967579