- Type: Linear analog out
- Range: 10cm-80cm, 0 to 3V
- Cost: $10-$15
- Distributors: Acroname, Hobby Engineering, etc
- Datasheet, Application note from SHARP
These sensors are very popular among roboticists and physical-computing hobbyists. There is an infrared LED and a sensor with some circuitry that measures how far an object is. One thing to watch out for is that when an object is closer than 10cm from the sensor, it reads as if it much farther. Check out the datasheet for the characteristics. Another thing to watch for is that the "JST" connector to the sensor is odd and hard to find so make sure you get a connector with the sensor!
This sensor must be used with the Analog/Digital I/O board plugged into one of the Analog ports configured as an Analog Input. Connect the +5V, GND and analog outputs to the +5V, GND, and analog input pins (respectively). Check the datasheet for the pinout as the pins are not in that order
- Type: Powered digital output sensor
- Range: 2cm - 3m (1" to 3.3')
- Cost: $30
- Distributors: Parallax
- Datasheet
These are not supported yet!
- Type: Powered digital output sensor
- Range: 20ft
- Cost: $8
- Distributors: Parallax
- Datasheet
PIR sensors are what you find in motion detectors: they scan and search for passive IR reflections (basically large animals like humans :) "The PIR Sensor detects motion up to 20 feet away by using a Fresnel lens and infrared-sensitive element to detect changing patterns of passive infrared emitted by objects in its vicinity. Inexpensive and easy to use, it's ideal for alarm systems, motion-activated lighting, holiday props, and robotics applications." The sensor uses 5V and has an ouput pin that is high or low depending on whether something is detected. This sensor is best used with the Analog/Digital I/O board as a Digital Input (any input) but must also have the +5V power pin connected to +5V from the board to power it.