{"497401":{"#nid":"497401","#data":{"type":"news","title":"Dr. Massimo Ruzzene: Defining the Future of Sensing Technology","body":[{"value":"\u003Cp\u003EProfessor Massimo Ruzzene\u2019s research on integrated vehicle health monitoring (\u003Ca href=\u0022http:\/\/ae.gatech.edu\/sites\/default\/files\/img\/Integrated%20Vehicle%20Health%20Monitoring.pdf\u0022\u003EIVHM\u003C\/a\u003E) has made him bullish about the future.\u003C\/p\u003E\u003Cp\u003EHe readily envisions a time when commercial airlines will be able to abandon conservative and costly maintenance schedules because their planes will be able to sense impending malfunction in one of their systems the same way a human might avoid a root canal by heeding the warnings of a simple tooth ache.\u003C\/p\u003E\u003Cp\u003E\u201cThe goal is condition-based maintenance and component-damage tracking. It\u2019s all possible, but you need to think outside the box if you want to advance the state of the art,\u201d he said recently.\u003C\/p\u003E\u003Cp\u003E\u201cWe can\u2019t keep pushing the same legacy sensors \u2013 sensors we developed 30 or 40 years ago \u2013 and expect to realize new benefits. We need sensors that are built for the information they transmit.\u201d\u003C\/p\u003E\u003Cp\u003ERuzzene\u2019s IVHM research is doing just that.\u003C\/p\u003E\u003Cp\u003EOver the last six years, his research team has developed three next-generation ultra-sonic sensors, each engineered to monitor the health and\/or usage of modern aerospace, civil and mechanical systems.\u003C\/p\u003E\u003Cp\u003EOne of his designs, the Frequency-Steered Acoustic Transducer (FSAT) has a patent pending. Two others - the Acoustic Wave Rosette (AWR) and the Impact Directionality Revealer (IDR) - were the subject of an award-winning paper, written by Ruzzene\u2019s doctoral student Matteo Carrera (see box).\u003C\/p\u003E\u003Ctable width=\u0022200\u0022 border=\u00221\u0022 cellspacing=\u00221\u0022 cellpadding=\u002220\u0022 align=\u0022right\u0022\u003E\u003Ctbody\u003E\u003Ctr\u003E\u003Ctd\u003E\u003Cp\u003EDr. Ruzzene\u0027s doctoral student,\u0026nbsp;\u003Ca href=\u0022http:\/\/www.prism.gatech.edu\/~mcarrara3\/\u0022\u003E\u003Cstrong\u003EMatteo Carrara\u003C\/strong\u003E\u003C\/a\u003E\u0026nbsp;has worked alongside his mentor to explore the next generation transducers. Carrara\u0027s recently authored paper on the subject, \u0022Frequency-wavenumber Design of Spiral Macro Fiber Composite Directional Actuators\u0022 was selected for the 2015 Best Student Presentation Award at the SPIE 22nd International Symposium on Smart Structures and Materials and Nondestructive Evaluation and Health.\u0026nbsp;\u003Ca href=\u0022http:\/\/ae.gatech.edu\/sites\/default\/files\/img\/Matteo%20Carrara.pdf\u0022\u003E\u003Cstrong\u003EFind out more\u003C\/strong\u003E\u003C\/a\u003Eabout Carrara\u0027s award-winning work.\u003C\/p\u003E\u003C\/td\u003E\u003C\/tr\u003E\u003C\/tbody\u003E\u003C\/table\u003E\u003Ch2\u003EThe Fourier Framework\u003C\/h2\u003E\u003Cp\u003EWhat sets these transducers apart from their predecessors is their design, which is dictated by the Fourier Transform, a mathematical framework that gives an excellent representation of things that are periodically in time and space.\u003C\/p\u003E\u003Cp\u003E\u201cThe Fourier Transform allows us to specify the design in the \u2018Fourier-Space\u2019 and directly obtain the resulting shape of the transducer through a simple mathematical process,\u201d he noted.\u003C\/p\u003E\u003Cp\u003EFabricated from piezoelectric materials (PZT or PVDF), these transducers adopt a complex surface pattern that is, itself, determined by the Fourier Framework. The unique shape allows it to more efficiently and accurately convert sound waves into signals that will pinpoint areas of concern or risk. From a practical standpoint, it requires just two electrical wires (to receive and elicit signals) - not the myriad wires used in legacy sensors.\u003C\/p\u003E\u003Cp\u003E\u201cThe importance of reducing wires cannot be underestimated,\u201d Ruzzene points out.\u0026nbsp;\u003Cbr \/\u003E\u201cIf an aircraft manufacturer distributes legacy sensors throughout the airframe to monitor health and damage, they are bound to find that the added weight of the wires and hardware will negate many if not all of the advantages of the lighter weight composites they are using to build the structure.\u201d\u003C\/p\u003E\u003Cp\u003EOnce it is adhered to the surface, the new generation of transducers is ready to receive an acoustic wave that will begin the diagnostic. The unique deformation that results from this acoustic charge sends out elastic waves in different directions - each determined by the frequency of the original signal. All of the waves traveling through the material elicit an echo or return wave which is picked up by the sensor and can be analyzed. When an anomalous wave signal returns to the sensor, it is evidence of a defect of some type.\u003C\/p\u003E\u003Cp\u003EIf this sounds like ultrasound technology of old, it is.\u0026nbsp;With a twist: it works much better and requires much simpler hardware.\u003C\/p\u003E\u003Cp\u003E\u201cWe can create an image of the defect and know exactly where it is by directing waves in different directions,\u201d notes Ruzzene. \u201cBut we are not bound to all of the wires and hardware that adds weight to legacy sensors.\u201d\u003C\/p\u003E\u003Cp\u003EEventually, Ruzzene thinks these sensors will be able to replace phased array technology - a system in which multiple sources send acoustic waves through the material at different points in time. The location of any anomalous results is determined by analyzing the constructive and destructive interference.\u003C\/p\u003E\u003Cp\u003E\u201cThis still works, but it has its weaknesses,\u201d Ruzzene notes. \u201cThe wires themselves are not so robust, so they have to be maintained or replaced on a regular basis. And the diagnostic equipment is heavy, expensive, and not-transportable. You cannot take it onto the plane to conduct the assessment while you are in flight, for instance.\u201d\u0026nbsp;\u003C\/p\u003E\u003Ch2\u003EThe next generation begins: FSAT, AWR, IDR\u003C\/h2\u003E\u003Cp\u003E\u0026nbsp;The first of these, the\u0026nbsp;\u003Cstrong\u003EFrequency Steered Acoustic Transducer\u003C\/strong\u003E\u0026nbsp;(FSAT) takes acoustic information and transforms it into elastic waves that can be steered in different directions to detect defects.The three Fourier-designed sensors that Ruzzene\u2019s team has already developed make a strong case for changing the way diagnostics are done. More models are bound to be developed, but the first three have shown promise in effectively monitoring hot spots or damage \u2013 an improvement which could significantly reduce maintenance, inspection, and, over the long-term, structure replacement costs.\u003C\/p\u003E\u003Cp\u003EThe\u0026nbsp;\u003Cstrong\u003EAcoustic Wave Rosette\u003C\/strong\u003E\u0026nbsp;(AWR) takes the Fourier design a step further to house multi-component strain sensing capabilities in one device. When the underlying structure is in some way deformed, the AWR\u2019s multi-band spatial filter detects it by monitoring peaks shift in the wavenumber domain. The resulting data can tell\u003C\/p\u003E\u003Cp\u003EThe military has shown a lot of interest in the third Fourier-designed sensor, the\u0026nbsp;\u003Cstrong\u003EImpact Directionality Revealer\u003C\/strong\u003E\u0026nbsp;(IDR), which can deliver useful information on the location and source of damage caused by external objects (everything from space debris to bullets).engineers about its normal and shear strain components.\u003C\/p\u003E\u003Cp\u003EWhere prior designs might require three sensors to determine the location of the impact and resulting damage, it takes just a single IDR device to produce data about the location, size, and directional origin of impact damage. It does this by using a combination of wave frequency and amplitude data.\u003C\/p\u003E\u003Cp\u003E\u201cIf you are trying to determine where the location where a bullet impacted the structure, and you have several bullet impacts, you can determine the direction of each one by measuring the frequencies of the waves that each impact creates,\u201d Ruzzene said.\u003C\/p\u003E\u003Ch2\u003ERuzzene predicts that time, money, and accuracy will be the big winners when the next generation of sensing technology is fully integrated into industry. Safety will remain constant.\u003C\/h2\u003E\u003Ch2\u003EIs zero down-time maintenance\u0026nbsp; attainable?\u003C\/h2\u003E\u003Cp\u003E\u201cPeople talk about zero down-time maintenance, and that may be possible, but wherever we are headed, it\u2019s widely understood that the current schedule of structural maintenance stops is overly conservative,\u201d he said.\u003C\/p\u003E\u003Cp\u003ECurrent best practices call for multi-day maintenance stops scheduled around the number of take-off-and landing-cycles a plane has completed. This approximates a certain number of flight hours, and assumes a certain amount of structural stress due to the repeated pressurizing and depressurizing of the cabin. It\u2019s all averaged out into a profile.\u003C\/p\u003E\u003Cp\u003EAnd it\u2019s all very expensive.\u003C\/p\u003E\u003Cp\u003EMaintenance stops mean everything comes to a halt. Flights are put on hold, and parts of the aircraft are taken apart for direct inspection. Expensive machines and trained engineers are brought out to run tests.\u003C\/p\u003E\u003Cp\u003E\u201cIt catches 9 out of 10 issues, sure, but it\u2019s a little like going to the doctor every month instead of once a year when you are healthy. It\u2019s worth asking if the cost of that visit \u2013 in terms of lost work time, inconvenience, dollars spent \u2013 could be better incurred by something that would improve your health instead of monitoring it,\u201d he said.\u003C\/p\u003E\u003Cp\u003E\u201cWhat we\u2019re doing now is working, and that\u2019s good. People are generally safe and planes are flying. But we can do better. By retiring the legacy sensors for this new design, we can establish a fundamentally better system that does not imply any additional complications right from the start. As engineers, that\u2019s the kind of challenge we want to take on.\u201d\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003E\u003Cem\u003EProfessor Massimo Ruzzene is the director of the\u003Ca href=\u0022http:\/\/www.ruzzene.gatech.edu\/\u0022\u003E\u0026nbsp;Vibration and Wave Propagation Laboratory\u003C\/a\u003E, which conducts research in metamaterials, structural health monitoring, structural dynamics, and vibroacoustics.\u0026nbsp; Currently serving a two-year appointment as a program manager for the National Science Foundation, he has participated in projects funded by the US Air Force, US Army, US Navy, DARPA, NASA, NSF, and by Boeing, Raytheon and TRW. M. Ruzzene is the recipient of the 2002 Young Investigator Award from ONR and of group achievement awards from NASA. He is a Fellow of ASME, an Associate Fellow of AIAA, and a member of ASA and of AHS.\u003C\/em\u003E\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Professor Massimo Ruzzene\u0027s research on integrated vehicle health monitoring (IVHM) has made him bullish about the future."}],"uid":"30502","created_gmt":"2016-02-09 14:12:15","changed_gmt":"2016-10-08 03:20:38","author":"Sapna Mistry","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2015-04-09T00:00:00-04:00","iso_date":"2015-04-09T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"497411":{"id":"497411","type":"image","title":"Dr. Massimo Ruzzene: Defining the Future of Sensing Technology","body":null,"created":"1455120000","gmt_created":"2016-02-10 16:00:00","changed":"1475895256","gmt_changed":"2016-10-08 02:54:16","alt":"Dr. Massimo Ruzzene: Defining the Future of Sensing Technology","file":{"fid":"204631","name":"dsc_0798.jpg","image_path":"\/sites\/default\/files\/images\/dsc_0798_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/dsc_0798_0.jpg","mime":"image\/jpeg","size":1384676,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/dsc_0798_0.jpg?itok=R5r8-y8X"}}},"media_ids":["497411"],"groups":[{"id":"1239","name":"School of Aerospace Engineering"}],"categories":[{"id":"136","name":"Aerospace"},{"id":"134","name":"Student and Faculty"},{"id":"145","name":"Engineering"},{"id":"135","name":"Research"}],"keywords":[{"id":"2082","name":"aerospace engineering"},{"id":"126111","name":"GT-AE"},{"id":"171666","name":"Integrated Vehicle Health Monitoring"},{"id":"171667","name":"IVHM"},{"id":"134521","name":"Massimo Ruzzene"},{"id":"134531","name":"Matteo Carrara"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":["kathleen.moore@ae.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}