Synchronized Multi-channel and Low Power Wireless Acoustic Emission Sensor Network for Radar Tower Structural Monitoring

ABSTRACT: Many of the radar sites throughout the world are over 50 years old and ongoing sustainment and inspections of these facilities is in critical need. We propose to develop and test a wireless, multi-channel and low power consumption Acoustic Emission (AE) sensor network system to monitor the steel and composite radar tower structures for fatigue and stress corrosion cracking. The proposed system leverages our extensive structural monitoring experience for steel highway bridges. The AE sensor system will be able to detect and discern damage sound from the environmental noise, and localize the damage site within a few inches with a sparse sensor network. Phase I will focus on developing and testing the feasibility of the AE sensor network for representative structures with cyclic fatigue tests in the lab, and field trials of the prototype device on a target radar tower; Phase II will further develop and improve the system and deploy the system on the radar tower for long term data collection in the operational environment. The end-product will also be ready to transition to real radar system applications for other civil infrastructures.; BENEFIT: AE-WSN has significant commercial potential for applications in both military and civil structure integrity monitoring and maintenance. Without knowledge of damage condition, radar tower in service need to be inspected based on a fixed schedule. Large safety factors are usually applied which significantly increases maintenance cost. On the other extreme, as some of the radar towers are located in extremely remote and desolate locations, inspections of those towers may be skipped over some extended period of time, leading to potential severe structural failures. The proposed tool provides accurate and reliable assessment of damage status and fatigue life. Condition-based maintenance can be performed, which greatly reduces costs and labors. Both government and commercial organizations will benefit from the development of AE-WSN system.