Sensor network and information interoperability integrating IEEE 1451 with MIMOSA and OSA-CBM

Open Architecture Software Design for Online Spindle Health Monitoring

“…As an analytic wavelet, the complex Morlet wavelet chosen in this module has been identified as an appropriate base wavelet for defect detection [4]. Another advantage of the complex Morlet wavelet is that it has explicit expression in the frequency domain as: 2 (f(f m(fe) e fb with symbols fb and fc being the bandwidth and wavelet center frequency parameters, respectively. Equation (1) is designed and implemented in the module as a formula node, which is used to evaluate the mathematical expressions.…”

“…Instead of fitting an empirical model to the Frequency Response Function (FRF) from artificial excitations (e.g., hammer strikes) as the traditional approach does, the SSI technique accounts for dynamic changes caused by the rotations of the spindle without the need for artificial excitations, and extracts the modal parameters from its measured output only, thus satisfying the requirement of online operation. Mathematically, the SSI technique is formulated and solved using a discrete time-state space model of a linear, time-invariant system (e.g., the spindle) without known external inputs according to the following equation: Xk+l =: Axk + Wk lYk Cxk + Vk (2) where xk=x(kAt) is the discrete-time state vector, Yk is the system response vector, A is the state matrix, and C is the output matrix. The two components, Wk and Vk, represent the disturbance noise to the spindle and measurement noise due to sensor inaccuracy, respectively, and are stochastic in nature.…”

“…The two components, Wk and Vk, represent the disturbance noise to the spindle and measurement noise due to sensor inaccuracy, respectively, and are stochastic in nature. Equation (2) indicates that the new state of the spindle physical system, xk 1, can be obtained by the sum of the state matrix A multiplied with the old state vector Xk and the disturbance noise vector Wk. As a result, the dynamic behavior of the spindle is completely characterized by the state matrix A.…”

“…The layered architecture shown in Figure 1 facilitates the integration and interchangeability among sensors, electronics, and software components [2,3], which allows flexibility for upgrading or expanding the system by incorporating new functions into corresponding layers. By taking advantage of the open systems architecture, this paper presents the software design of an online spindle health monitoring system.…”

Efficient link management for the wireless communication of an ocean current turbine testbed

“…Therefore, the ocean-side component of the PHM system processes the data locally and then stores the resulting values in the Data Store (DS) component. The DS consists of a MySQL database and MIMOSA OSA-CBM [11,12] compliant SOAP/XML Web Services (WS) [9] implemented on Apache Tomcat with Java EE. External interaction with the system from the shore may also be initiated through the DS interface.…”