Instructed on: 09-Dec-2011 | Session: #04 Basics & Applications By: Mohanad Yehia Topic Code: TCW-03-2012 All Copy Rights Saved to the 7th Students’ Conference on Communication and Information Based in the Faculty of Computers and Information Cairo University – Egypt 2011/2012 www.scci-cu.com
What’s a Sensor?! Sensors’ quality Measurement definitions Common errors Sensors types
A sensor is a device that measures a physical quantity and converts it into a signal which can be read by an observer or by an instrument.
A good sensor should be:• Sensitive to the measured property.• Insensitive to any other property likely to be encountered while measurement.• Does not influence the measured property.
A sensors sensitivity indicates how muchthe sensors output changes when themeasured quantity changes.
It’s difference between the real value ofthe property and the average value of themeasurements of that property.
The resolution of a sensor is the smallestchange it can detect in the quantity that itis measuring.
The output signal is NOT zero when the measured property is zero. The sensitivity is not constant over the range of the sensor. The output signal slowly changes independent of the measured property.
Most sensors are affected by temperature. The approximation of the output value.
Parking sensors: used to alert the driver of unseen obstacles during parking maneuvers.
Speedometer: used to measure the instantaneous speed of a land vehicle.
Fuel meter: used to measure the level of fuel in the tank.