{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

MKM 503E-Week3_Nonconventional_ Sensors

MKM 503E-Week3_Nonconventional_ Sensors - MKM 503E Week3...

Info icon This preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
MKM 503E- Week3 Nonconventional Sensors prepared by Assist. Prof. Pinar Boyraz, PhD 1 ITU, 2011
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Outline 2 Piezoelectric sensing Close look at an analog accelerometer LIDAR and IMU ITU, 2011 Non-diagonal terms represent smart materials
Image of page 2
Piezoelectricity-1 3 ITU, 2011 An effect in which energy is converted between mechanical and electrical forms Discovered by 1880s by Curie’s a pressure (piezo >> pressure in Greek) is applied to a polarized crystal, the resulting mechanical deformation results in an electrical charge. Example: piezoelectric microphones Alternatively, when an electrical charge is applied to a polarized crystal, the crystal undergoes a mechanical deformation which can in turn create an acoustical pressure Example: piezoelectric speakers
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Piezoelectricity-2 4 ITU, 2011 Electrets are solids which have a permanent electrical polarization. Electrets are electrical analogs of magnets. The alignment of the internal electric dipoles would result in a charge which would be observable on the surface of the solid. In these structures, each cell of the crystal has an electric dipole, and the cells are oriented such that the electric dipoles are aligned. Again, this results in excess surface charge which attracts free charges from the surrounding atmosphere making the crystal electrically neutral. If a sufficient force is applied to the piezoelectric crystal, a deformation will take place. This deformation disrupts the orientation of the electrical dipoles and creates a situation in which the charge is not completely canceled. This results in a temporary excess of surface charge, which subsequently is manifested as a voltage which is developed across the crystal.
Image of page 4
Piezoelectricity-3 5 ITU, 2011 Piezoelectric linear transducer
Image of page 5

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern