tag:blogger.com,1999:blog-75092898072498290882012-02-16T17:43:54.554-08:00Learn about the concept of smart structures and the various elements or materials used in smart structures for vibration control like sensor patch, controller patch and actuator patch.Naveed Naikhttp://www.blogger.com/profile/12624637703831895201noreply@blogger.comBlogger21100tag:blogger.com,1999:blog-7509289807249829088.post-37180156257245144202008-08-25T22:02:00.001-07:002008-08-25T22:02:30.460-07:00<div style="text-align: justify; color: rgb(0, 0, 0);">The dictionary definition of the word “Smart” (brisk, spirited, mentally alert, bright, clever) is not quiet adequate for an engineer.<br /><br />For an engineer “A Smart Structure” means a structure that can sense an external disturbance and respond to that with active control in real time to maintain the mission requirements. A Smart Structure typically consists of a host structure incorporated with sensors and actuators coordinated by a controller.<br /><br />The integrated structured system is called Smart Structure because it has the ability to perform self diagnosis and adapt to environmental change. One promising application of such smart structure is the control and suppression of unwanted structural vibrations.</div><div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/7509289807249829088-3718015625724514420?l=smartstructures.blogspot.com' alt='' /></div>Naveed Naikhttp://www.blogger.com/profile/12624637703831895201noreply@blogger.com0tag:blogger.com,1999:blog-7509289807249829088.post-34126182908000883492008-08-25T22:01:00.001-07:002008-08-25T22:01:22.168-07:00<span style="color: rgb(0, 0, 0);">Smart Structure comprise of host structure along with Sensors, Actuators &amp; controller networks. Consider a simply supported beam as a smart structure.</span><br /><div style="text-align: justify; color: rgb(0, 0, 0);"><br /><div style="text-align: center;"><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://3.bp.blogspot.com/_fKYXbBmXz4k/SK1PkBkLALI/AAAAAAAAAIw/1ueYQ5Rl3n8/s1600-h/Img1+Smart+Structures.jpg"><img style="margin: 0px auto 10px; display: block; text-align: center; cursor: pointer;" src="http://3.bp.blogspot.com/_fKYXbBmXz4k/SK1PkBkLALI/AAAAAAAAAIw/1ueYQ5Rl3n8/s400/Img1+Smart+Structures.jpg" alt="" id="BLOGGER_PHOTO_ID_5236929422015791282" border="0" /></a><a href="http://activevibrationcontrol.blogspot.com/2008/08/smart-structure.html"><span style="font-weight: bold;">Basic Elements of a Smart Structure</span></a><br /><br /></div>The major components are:<br /><br /><span style="font-weight: bold;"> Sensor Patch</span><br />It is bonded to the host structure (Beam). It is generally made up of piezoelectric crystals (one of the smartest materials). It senses the disturbance of the beam and generates a charge which is directly proportional to its strain. Direct piezoelectric effect is used here.<br /><br /><span style="font-weight: bold;"> Controller</span><br />The charge developed by the sensor is given to the controller. The controller lines the charge according to suitable control gain and then the charge is fed to the actuator. Controller also forms the feed back transfer function for this system.<br /><br /><span style="font-weight: bold;"> Actuator Patch</span><br />The lined up charge from the controller is fed to the actuator. An actuator is a piezoelectric patch bonded to the host. Due to the input voltage, actuator causes pinching action (or generates shear force along the surface of the host which acts as the damping force and helps in the attenuating vibration motion of the beam. Converse piezoelectric effect is used here.<br /><br /></div><div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/7509289807249829088-3412618290800088349?l=smartstructures.blogspot.com' alt='' /></div>Naveed Naikhttp://www.blogger.com/profile/12624637703831895201noreply@blogger.com0