Movement Sensors

Motion sensors are of course used to detect moving objects. The sensors are programmed to activate a command once a specific movement is detected. Motion can be be detected in various ways: infrared, optics, radio frequencies, sound, vibration, and magnetism. In some of these cases, motion sensors do not really detect motion but rather measures other factors that can expose movement such as passive infrared detectors. Passive Infrared Detectors are the types of sensors you see for residential burglar alarms. The data that the sensors gather are translated mechanically or electronically. Vibration sensors use piezospeakers. When it senses vibrations a voltage is released to give a signal or command. Optic motion sensors have nothing to do with sight. From what I could see, optic motion sensors use fiber optic lines as a part of the sensor module. I thought optic meant something to do with a camera that would recognize and track an object. Mechanical translations are like switches that turn on or off, which can give a command upon a certain movement. Electronically, if the sensor detects a change in say infrared patterns then an electric signal is turned on to activate a command. Currently motion sensing is very successful in gaming but has great promise in other industries such as military and medical applications. The farther sensor has to detect the worse the detection is as the area to be detected becomes larger. Reading Kayleigh's blog, I found the hair sensor to be interesting. Kind of surprised to see that we are using human hairs to use for the sensor industry. Reading Matthew Tedesco's blog, the positive displacement meter reminded me of those Japanese water barrels that are filled with water but then once the water reaches a certain point the barrel tips over and the water rushes out. I wonder if those things aren't just used for aesthetics and had a measurement purpose to them. So it seems that a lot of these sensors are dependent on some kind of component that measures a current or voltage, or uses electricity to measure. I think most of these sensors are well established with the exception of motion sensors. I think motion sensors have lagged behind because you have to identify and measure moving objects. I'm sure it's especially harder when the sensor is also moving.


http://www.pickar.caltech.edu/e103/Final%20Exams/Motion%20Sensing%20Technology.pdf
http://en.wikipedia.org/wiki/Motion_detection