Difference between revisions of "SparkFun: 0.5" Force Sensitive Resistor"

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== Overview ==
 
== Overview ==
  
The [https://www.sparkfun.com/products/9375 SparkFun 0.5" Force Sensitive Resistor] varies its resistance based on the amount of force applied to it. The larger the force, the lower the resistance of the device. When no force is being applied, the resistance is larger than 1MΩ. Like a regular resistor, it only has two leads.
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The [https://www.sparkfun.com/products/9375 SparkFun 0.5" Force Sensitive Resistor] varies its resistance based on the amount of force applied to it. The larger the force, the lower the resistance of the device. When no force is being applied, the resistance is larger than 1MΩ. Like a regular resistor, it only has two leads. The FSR Integration Guide can be accessed [http://www.sparkfun.com/datasheets/Sensors/Pressure/fsrguide.pdf here].
  
 
== Bone Usage ==
 
== Bone Usage ==
  
The force-sensitive resistor works well when used with the BeagleBone's analog inputs. The schematic below outlines how to hook it up. This image is modified and originally from the [http://www.sparkfun.com/tutorials/269 SparkFun tutorial on the force-sensitive resistor].
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The force-sensitive resistor works well when used with one of the BeagleBone's analog inputs. The images below outline how to hook it up. This schematic on the left is modified and originally from the [http://www.sparkfun.com/tutorials/269 SparkFun tutorial on the force-sensitive resistor].
  
[[File:Force-Sensitive Resistor Schematic.jpg]]
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[[File:Force-Sensitive Resistor Schematic.jpg|x350px]] [[File:Force-Sensitive Resistor Bone hookup.jpg|x350px]]
  
A 27kΩ resistor is used to connect the 3.3V source from the Bone to one pin of the force-sensitive resistor. Then, the other pin of the force-sensitive resistor is connected to ground. An analog pin (AIN) on the Bone connects between the two resistors, and values can be read off of that AIN.
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A 27kΩ resistor is used to connect the 3.3V source (pin 3) from the Bone to one pin of the force-sensitive resistor. Then, the other pin of the force-sensitive resistor is connected to ground (pin 1). An analog pin (AIN) on the Bone connects to the node containing both resistors, and values can be read off of that AIN. I'm using AIN5 (pin 36) to read values on the Bone.
  
 
== Example Program ==
 
== Example Program ==

Revision as of 13:23, 22 September 2012

The force-sensitive resistor.

Overview

The SparkFun 0.5" Force Sensitive Resistor varies its resistance based on the amount of force applied to it. The larger the force, the lower the resistance of the device. When no force is being applied, the resistance is larger than 1MΩ. Like a regular resistor, it only has two leads. The FSR Integration Guide can be accessed here.

Bone Usage

The force-sensitive resistor works well when used with one of the BeagleBone's analog inputs. The images below outline how to hook it up. This schematic on the left is modified and originally from the SparkFun tutorial on the force-sensitive resistor.

Force-Sensitive Resistor Schematic.jpg Force-Sensitive Resistor Bone hookup.jpg

A 27kΩ resistor is used to connect the 3.3V source (pin 3) from the Bone to one pin of the force-sensitive resistor. Then, the other pin of the force-sensitive resistor is connected to ground (pin 1). An analog pin (AIN) on the Bone connects to the node containing both resistors, and values can be read off of that AIN. I'm using AIN5 (pin 36) to read values on the Bone.

Example Program

More to come...