Damage identification in vibrating rotor-shaft systems by efficient sampling approach

In the paper a stochastic method for fault detection and identification in the shafts of rotating machines is proposed. This approach is based on the Monte Carlo simulations of rotor-shaft lateral–torsional–longitudinal vibrations mutually coupled by transverse cracks of various possible and randomly selected depths and locations on the shaft. For this purpose the structural hybrid model of a real faulty object is applied. This model is characterized by a high practical reliability and great computational efficiency, so important for many hundred thousand single numerical simulations necessary for a creation of the databases applied for inverse problem solution finally leading to crack identification. These databases are created with an arbitrary assumed probability densities of crack parameters which ensures appropriate spread of the dynamic responses of the considered faulty mechanical system. A sufficiently large database determined for the investigated object enable us to estimate almost immediately, i.e. within less than 1 s, the crack depth and axial position with identification errors not exceeding 9% and 5%, respectively. Thus, the proposed method seems to be a very convenient diagnostic tool for engineering applications in the industry.     

Real-Time FPGA Implementation of Parallel Connected Component Labelling for a 4K Video Stream

Journal of Signal Processing Systems - In this paper, a hardware implementation in reconfigurable logic of a single-pass connected component labelling (CCL) and connected component analysis (CCA)...     

Simulation of Dynamic Interaction between the Railway Bogie and the Track in the Medium Frequency Range

In the present paper, the dynamicinteraction between a bogie of a modern railwaypassenger car and a track is considered with the helpof a discrete-continuous mechanical model. This modelenables us to investigate the bending-torsional-axialvibrations of the wheelsets coupled with the verticaland lateral vibrations of the track through thewheel-rail contact forces. The numerical results areobtained in the form of frequency response functionsfor the linearized bogie-track system as well as bymeans of computer simulation of forced vibrationsperformed for the non-linear system. Particularlysevere interaction between the bogie and the track iscaused by kinematic and parametric excitation from thetrack and by kinematic excitation due to wheel treadpolygonalization.