Hardware: Study of sensors

1 minutes read

To develope products using sensors, it is essential to have a knowledge of variety of sensors. This page lists type of sensors, demonstrates about its characteristics and how they can be applied to the real world.

Distance Sensor

 UltrasonicInfraredLaser
MethodSoundLightLight
FrequencyHighLow-
Consdistance mesurementObject detectionAccuracy
ProsEnvironmental factors (observe signal by soft objects)inaccurate distance measurementCost

*Laser beam is often used to measure long distance.

Ultrasonic

Ultrasonic sensors often enhances distance measurement to the object very accurately.

PARTSDatasheet
parallax: PINGPING
HC-SR04 (Similar to PING but cheaper)HC-SR04

Infrared

One of the great features of using infrared sensor is thermal emission. This enhances object come and go by thermal emission. However, thermal emission should be taken carefully depends on environmental factors. the sensor only able to detect object within a range but cannot accurately sense distnace.

PARTSDatasheet
Infrared Sensor SwitchFoo
Compound EyeFoo

Compound eye sensor is consisted of a number of infrared-sensitive transistor and LED

Types:

  • Passive infrared sensor: Senses thermal radiation transferred to infrared.

  • Active infrared distance sensor: Detects returned sent light from infrared. This notifies distance in a range.

Applications:

Hand Dryer, Water tab, rubish bin.

Smoke and Gas Sensor

There are variety of sensors which senses different kind of chemicals as show below. MQ2 is one of the cheapest Analog sensor used among developers.

PARTSApplicationDatasheet
MQ-2LPG
I-butane
Propane
Methane
Alcohol
Hydrogen
Smoke
Foo
MQ-3, MQ-303AAlcohol Checker
Breathalyser
Foo
MQ-4CH4
Natural Gas
Foo
MQ-7Carbox MonoxideFoo
MQ-8HydrogenFoo
MQ-9Carbon Monoxide
CH4
LPG
Foo

Switches

Touch Sensors - work the same way as the buttons which need voltage and ground lines.

Types
Buttons
Microswitch
Potentiometer
QT 113 - Touch Sensor
FlexiForce - analogRead
Touch Sensors

Movement

TypesNotes
Tilt Sensoradc
vibration sensoradc
rotary encodercounts the rotation of the object
Thumbstickused in joystick of playstation. two types: 3 pins and 5 pins
PIR sensorvarious range of products depends on sensing distance and angle.

Light

TypesNotes
Flame sensorKY-026
Light-dependent resistor (LDR)visible ray resistors
Line detection (line tracer) 
color detection 
color display (RGB LED) 

Updated:

Leave a Comment