1. Slide # 1 Project topics List of projects 1.Automotive accelerometer (ONER) 2.Explosive detection systems 3.Mass flow and pressure sensors/controllers (WILSON) 4.Cooled and Uncooled IR sensors (OMAR) 5.Nanoscale bio-sensors for pathogen detection (DANIELS) 6.MEMS gyroscopes for navigation (ASIF) 7.RFID based temperature and humidity sensors (SULTANA) 8.Strain sensors for prognostics in airplanes and bridges (PATEL) 9.Volatile organic compound sensors (DULAIMY) 10.Automotive O 2 and NO x sensors (DIWAN) 11.MEMS/NEMS sensors for pathogen and toxic gases (SHETU) 12.Graphene based chemical sensors (UDDIN) 13.MEMS SENSORS based Photoacoustic spectroscopy (TALUKDAR)

2. Slide # 2 Linear Optical sensors II The PSPDs can be one or two dimensional to track either unidirectional or planar movements. Unlike CCDs, which consist of discrete photodiodes, PSD is uniform and non-discrete Typical applications of this type of sensors is in detecting small displacements and on-line measurement of height, such as, PC board inspection, level control, etc. Also, to determine presence of objects i.e. hand under tap, or the uniformity of rotating objects such as medicine caps, bottles, etc. The equivalent circuit shown has distributed capacitance and resistance, so the time constant is dependent on the position of the beam Typical response time is 1-2  s Spectral response is 320 – 11000 nm typically

3. Slide # 3 Optical sensors: PSPD

4. Slide # 4 Optical sensors: PSPD problem Calculate the minimum displacement of a microcantilever that can be sensed if the measurement uncertainly of the PSPD is 0.5 um. Given that the microcantilever is positioned 10 cm away from the PSPD and the focal length of the lens for the PSPD is 2 mm. The angle between the incident and reflected beam is 30º.What can you do to improve the deflection sensitivity of the microcantilever?

5. Slide # 5 Ultrasonic sensor

6. Slide # 6 Ultrasonic sensor

7. Slide # 7 Operating principles Input ac voltage generates ultrasonic sound by periodically displacing the piezo-ceramic element. On the detector side the ultrasonic wave would periodically oscillate the piezo- transducer generating a small ac voltage that can be amplified.

8. Slide # 8 Velocity sensor Specifications for electromagnetic velocity sensor Velocity sensors can utilize the same principles of displacement sensor, and produce a response as a function of time. A typical velocity sensor, in a fixed direction can be based on a design similar to the LVDT. In this case, a permanent magnet can be attached to the moving part which will induce a differential voltage at the output proportional to the speed of the permanent magnet. Note that unlike LVDT, a constant voltage is produced only when there is a constant movement.