Evaluation mehods for health monitoring of aerospace structrures rotary joints

Sergio A Navarro, University of Texas at El Paso


In September 2007, the excessive vibrations played a significant role in the station operation since one of the rotary joints, which provides the station electrical energy, presented an anomaly. The replacement of its bearing components and re-lubrication were necessary to reduce the problem. To avoid a new anomaly, the inspection of the rotary joints performance continues by using the accelerometers data. This thesis presents three new approaches to monitor the vibrations at the International Space Station based on Root-Mean-Square, kurtosis, and Approximate Entropy (ApEn). MATLAB functions and codes were necessary to implement the three monitoring techniques results from the provided accelerometer datasets. The analyses consist in detecting the datasets with considerable vibrations and perform plots of the three techniques versus time for those datasets. In the end, the plot results are compared with Power Spectral Densities (PSD) plots. The plots results had shown that the RMS method was able to detect most vibrations, kurtosis was able to detect the two most excessive ones, and ApEn only detected the most excessive one. ^

Subject Area

Engineering, Civil|Engineering, Electronics and Electrical|Engineering, Mechanical

Recommended Citation

Navarro, Sergio A, "Evaluation mehods for health monitoring of aerospace structrures rotary joints" (2011). ETD Collection for University of Texas, El Paso. AAI1503740.