Future Applications of PZT Sensors in UAV Applications

     Aircraft health monitoring systems especially on unmanned systems are something that is coming around the corner in UAV development especially of larger, more expensive systems.  Having the ability to diagnose the structure of an aircraft real-time while in flight and make adjustments as required as well alert when maintenance needs to be done on certain areas before greater structural damage occurs would help add to the lifespan, survivability, and lower maintenance costs of future UAVs.  Piezoelectric (PZT) sensors may be one of the technologies that helps achieve this.
     Piezoelectric sensors work by using the piezoelectric effect to measure changes in pressure, acceleration, temperature, strain, or force and converting them into electrical charge.  These sensors take advantage of the ability of certain materials to accumulate electric charge in response to applied mechanical stress.  Piezoelectric sensors have the potential to be incorporated into future health monitoring systems on UAV's in a variety of ways but being used to monitor the structural integrity of an aircraft and assist in damage assessment is one way that has shown promise.  Experiments have shown that PZT sensors applied at critical locations on the aluminum or composite structure of an aircraft could measure the intensity of the load from accelerations of the aircraft as well as assist in damage assessment by comparing the difference in interpreted engineering parameters of damaged structure with healthy structure. (Sathyanarayana, 2013)  The potential to incorporate piezoelectric materials into composites shows promise for the potential of a light weight design that can be incorporated into an aircraft's structure with ease.
     One thing that would need to be developed to gain the full benefits from piezoelectric sensors however is a health monitoring algorithm to properly diagnose the information coming from the PZT sensors. (Sathyanarayana, 2013)  This is vital to proving how useful PZT sensors could be and whether they are able to just assess whether damage has been done or not, or whether they can also assess the intensity of the damage, specific location, and loading intensity. (Sathyanarayana, 2013)
 
 Reference:
Sathyanarayana, C., Raja, S., & Ragavendra, H. (2013). Procedure to Use PZT Sensors in Vibration and Load Measurements. Retrieved June 6, 2015, from http://www.hindawi.com/journals/smr/2013/173605/