Structural health monitoring aims to provide an accurate diagnosis of the condition of civil infrastructures during their life span using data acquired by sensors. Wireless sensor networks represent a suitable monitoring technology to collect reliable information about the structure's condition, replacing visual inspections, and reducing installation and maintenance time and costs. This article introduces a time synchronized and configurable wireless sensor network for structural health monitoring enabling a highly accurate identification of the modal properties of the monitored structure. The wireless sensor nodes forming the network are equipped with a 3-axis digital accelerometer and a temperature and humidity sensor. The implemented Medium Access Control layer time synchronization protocol (μ-Sync) ensures a highly accurate synchronicity among the samples collected by the nodes, the absolute error being constantly below 10 μs, also when high sampling frequency (up to

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ter collisions (see e.g.[1], [3]). Such deficiencies are difficult for traditional control algorithms to handle. Often the This paper discusses a platform for prototyping control control algorithms assume constant sampling intervals and schemesfor networked control systems (NCS). The platform do not consider such asynchronic systems.provides tools for simulating various networks in connecAs the interest of automation industry rises towards diftion with real processes. The paperfocuses on an extension ferent networked systems, also wireless communication beto the MoCoNet platform [8], which is a unique environcomes an option for data transmission in networked control ment for monitoring and controlling processes over the Insystems. Wireless provides huge opportunities for efficient ternet in real-time. MoCoNet also provides capability of and flexible measuring in industrial systems, but it also inemulating different networks via network simulation. The volves some threats that need further research in connecplatform is extremely valuable for control design in NCS, tion with real process control systems. For evaluating and because the real processes can be first run over simulated researching different control algorithms in networked sysnetworks and different network congestion scenarios can tems, the MoCoNet system [6] has been developed. Mobe experimented. This paper extends the MoCoNet sysCoNet, abbreviated from Monitoring and controlling labotem by integrating it with the well known and widely acratory process over Internet, provides a platform to perform cepted network simulator [9], Ns2. The paper discusses networked control experiments with real processes. Besides various aspects of this novel integration of Ns2 with realan easy-to-use graphical user interface the MoCoNet systime operated control systems. The extension allows users tem provides tools for designing and tuning controllers for of the MoCoNet system to test the control algorithms for real case processes in networked control system setup, run-NCS with numerous wired/wireless technologies available ning real-time control experiments, and using a variety of in Ns2. Furthermore, the paper discusses the development network simulators to experience the effects of various netof a simple Java based GUI that is used to create virtual work technologies in control systems [5], [7]. Managing the networks in Ns2. networks in Ns2. experiments and scenario selections are all done over the Internet, and thus the system forms an outstanding remote control environment for both educational and research use.

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