Difference between revisions of "Sensors"

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=== Rotary Encoder ===
 
=== Rotary Encoder ===
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A rotary encoder is a device that measure ( or encodes ) rotational motion.  The old fashioned mice with a ball used dual rotery encoders one to measure motion in the x direction one to measure motion in the y direction.  This may be done using switching technology or by using optical methods ( so some encoders may be considered optical electronics ). Even stepper motors may be used as rotary encoders.  It normally requires a microcontroller ( or speciality chip ) to decode the signals.  In addition to mice rotary encoders are used for the user control on volume controls ( finally coupled to say digital potentiaometrs ), measure the position of joints in robots, or measuring the speed and/or positon of motors ( as in some servo motors ).
 
* [http://www.arduino.cc/playground/Main/RotaryEncoders  Reading Rotary Encoders]
 
* [http://www.arduino.cc/playground/Main/RotaryEncoders  Reading Rotary Encoders]
 
* [http://www.robotroom.com/Counter.html An Electronic Counter Project for Digital and Analog Signals, including Quadrature Encoders]
 
* [http://www.robotroom.com/Counter.html An Electronic Counter Project for Digital and Analog Signals, including Quadrature Encoders]
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=== Linear Encoder ===
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Like rotary encoders but for linear motion.  Modern digital calipers are based on this technology ( i think ).  Positioning of print heads in computers may also uses this to position the print head.
  
 
=== Temperature Sensor  ===
 
=== Temperature Sensor  ===

Revision as of 19:53, 30 March 2008

Accelerometers, Gyroscopes, Temperature Sensors, Pressure Sensors, ...


Accelerometer

These measure ( gasp ) acceleration. May be caused by gravity or the second derivative of position ( relative to an inertial frame ). Since acceleration is a vector to go the whole distace you need a 3 axis sensor, but often 1 or 2 D will do. Often the output is a voltage(s). Feed it to a microcontroller with an a to d converter, perhaps through an operational amplifier. Op amp

Gas sensor


Knock Sensor

Magnetic Field Sensor

Photo Diode/Transistor


Rotary Encoder

A rotary encoder is a device that measure ( or encodes ) rotational motion. The old fashioned mice with a ball used dual rotery encoders one to measure motion in the x direction one to measure motion in the y direction. This may be done using switching technology or by using optical methods ( so some encoders may be considered optical electronics ). Even stepper motors may be used as rotary encoders. It normally requires a microcontroller ( or speciality chip ) to decode the signals. In addition to mice rotary encoders are used for the user control on volume controls ( finally coupled to say digital potentiaometrs ), measure the position of joints in robots, or measuring the speed and/or positon of motors ( as in some servo motors ).

Linear Encoder

Like rotary encoders but for linear motion. Modern digital calipers are based on this technology ( i think ). Positioning of print heads in computers may also uses this to position the print head.

Temperature Sensor

some are analog some use microcontroller interfaces LM34, LM35

Further Reading