background image

 

 
Web Site: www.parallax.com 
Forums: forums.parallax.com 
Sales: [email protected] 
Technical: [email protected] 
 

 
Office: (916) 624-8333 
Fax: (916) 624-8003 
Sales: (888) 512-1024 
Tech Support: (888) 997-8267 
 

 

Copyright © Parallax Inc.   

 

Page 1 of 6 

Parallax QTI Sensor KickStart (#555-27401) 

 

 

What It Can Do 

 

Detects differences between light and dark objects 

 

Proximity detection to judge relative distance to an object 

 

Works as an analog sensor, but can be connected to a digital I/O pin 

The QTI Sensor uses an infrared light emitting diode and infrared phototransistor to provide 
simple but effective non-contact detection of patterns and objects. In either case, light emitted by 
the LED bounces off a surface or object, and is detected by the phototransistor. 

For pattern detection

, the sensor can differentiate between light and dark surfaces, such as a 

black line drawn on a piece of white paper (useful as a robot line follower). 

For object detection

, the sensor can judge whether it’s close to an object by how much infrared 

light is reflected from it (useful as a tabletop edge detector). 

 

Summary of Contents for 555-27401

Page 1: ...e connected to a digital I O pin The QTI Sensor uses an infrared light emitting diode and infrared phototransistor to provide simple but effective non contact detection of patterns and objects In either case light emitted by the LED bounces off a surface or object and is detected by the phototransistor For pattern detection the sensor can differentiate between light and dark surfaces such as a bla...

Page 2: ...frared light is reflecting off a nearby surface Parts List QTI Sensor BASIC Stamp HomeWork Board Propeller BOE Propeller QuickStart or Arduino Uno microcontroller solderless breadboard as needed 22 gauge solid conductor hookup wire Basic Wiring Power requirements 3 3 to 5 VDC Communication Analog output of capacitor decay time depending on level of infrared reflectivity Dimensions 1 25 x 0 37 in 3...

Page 3: ...e surface Or for object detection the farther the sensor is to the object The range of values depends on the microcontroller due to how the microcontroller measures the capacitor transfer decay time but is typically about 30 to 2000 The range will also depend on the reflectivity of the object Some objects like the black antistatic foam used to protect electronic circuit boards reflect little or no...

Page 4: ...alue Display Display value DEBUG HOME DEBUG CR DEBUG DEC Duration CLREOL PAUSE 250 Wait 250 ms repeat GOTO Read_Sensor Note When this program is run the BASIC Stamp Debug Terminal will automatically open Note Depending on surface reflectivity values will range from about 60 to 3400 Propeller BOE and Propeller QuickStart Propeller BOE Wiring Diagram Propeller QuickStart Wiring Diagram OBJ debug Ful...

Page 5: ...xSerial object library which is included with the Propeller Tool software download To view the results of the demonstration after uploading is complete run the Parallax Serial Terminal from the Run menu or press F12 Momentarily depress the Reset button on the Propeller QuickStart board to restart the program Depending on surface reflectivity values will range from about 3 to 2000 Arduino Uno void ...

Page 6: ...his displays the Serial Monitor window Momentarily depress the Reset button on the Arduino board to restart the sketch Note Depending on surface reflectivity values will range from about 40 to 1300 For More Information Visit the full documentation for the QTI Sensor 555 27401 available from its product page The QTI Line Follower AppKit 28108 contains four QTI sensors plus mounting hardware to atta...

Reviews: