1 Bolted Joint Integrity for Structural Health Monitoring of Responsive Space Satellites

New research initiatives are being dedicated to the task of creating the procedures and technologies necessary to reduce active satellite installation times from the current scale of years. One of the largest time consuming steps is the set of flight qualification tests requiring structural verification through methods that currently give no information on sources of undesired structural changes; the most common cause of these changes is a loose component such as a bolt. To assist with reducing the time of this process, structural health monitoring is being considered as a means of locating sources of damage when detected or verifying the structure through self-diagnostic techniques during assembly intervals. It is envisioned that this option would potentially allow traditional tests to be omitted. Piezoelectric wafer active sensors are utilized in a simple 2x2 network on a realistic satellite panel incorporating 49 bolts where damage is simulated by minimally loosened bolts. Both Acousto-Elastic and Electro-Mechanical Impedance methods are investigated for their capability to detecting damage. Experimental results show that the techniques utilized allow for damage detection and localization and present the possibility of eliminating the need for a baseline. I