echo '' ;

Archives

Embedded Sensor – ADXL345

This article is a continuation of the series on “Embedded Sensor – ADXL345” and carries the discussion on Size, Functional Diagram, Pin Configuration, Application, Features and Benefits, ADXL345 Interface accelerometer, and Projects with this accelerometer. This sensor from Analog Devices

Digital output data is formatted as 16-bit twos complement and is accessible through either an SPI (3- or 4-wire) or I2C digital interface.

Read more… →

Embedded Sensor – Proximity

A proximity sensor is a type of sensor that detects the presence or absence of an object or obstacle in close proximity to it without physical contact. It works by emitting an electromagnetic field or beam of electromagnetic radiation, and then detecting changes in the field or radiation caused by the presence or absence of an object. Proximity sensors are commonly used in various applications such as automatic door openers, touchless faucets, mobile devices for screen activation, and industrial automation for object detection.

Read more: Embedded Sensor – Proximity

Real-Time Usage

On Mobile

           This sensor installed on the front of an iPhone 5 next to the earpiece automatically turns off the touchscreen when the sensor comes within a predefined range of an object (such as a human ear) when using the handset.

On Parking Sensor

Ultrasonic parking sensor: Source

Parking sensor on a fender

Type of Proximity

  • Capacitive Proximity Sensors
  • Inductive Proximity Sensors
  • Magnetic Proximity Sensors
  • Optical Type
    • Photoelectric
    • PhotoCell
    • Infrared Proximity Sensor (Passive Thermal)
  • Ultrasonic Type
  • Hall Effect Type

Proximity Sensor Application

  • Parking sensors, systems mounted on car bumpers that sense distance to nearby cars for parking
  • Ground proximity warning system for aviation safety
  • Vibration measurements of rotating shafts in machinery
  • Top dead centre (TDC)/camshaft sensor in reciprocating engines.
  • Sheet break sensing in paper machine.
  • Anti-aircraft warfare
  • Roller coasters
  • Conveyor systems
  • Beverage and food can making lines
  • Improvised Explosive Devices or IEDs
  • Mobile devices
    • Touch screens that come in close proximity to the face
    • Attenuating radio power in close proximity to the body, in order to reduce radiation exposure
  • Automatic faucets

Other Proximity Sensor

PRD-12-8DP Inductive Type

LJ12A3-4-Z-BY-Inductive-Proximity-Senso

  • Types NPN
  • Type : PNP
    • Data Sheet : Inductive Proximity Sensor Detection Switch PNP Model: LJ12A3-4-Z/BY
    • Specification :
      • A component widely used in automatic control industry for detecting, controlling, and non-contact switching When proximity switch is close to some target object, it will send out control signal.
      • Model: LJ12A3-4-Z/AY
      • Output Type: PNP NC(Normally Close)
      • Detecting Distance: 4mm±10%
      • Theory: Inductive Sensor
      • Wire Type: 3 Wire Type (Brown, Blue, Black)
      • Switch Appearance Type: Cylinder Type, Aluminum Shell
      • Supply Voltage: DC 6-36V
      • Current: 200A
      • Detect Object: Iron
      • Diameter: 12mm
      • Cable Length: 1M/3.3Ft
      • 1 x Inductive Proximity Sensor Switch
    • Price Approximately :340rs (India)

Embedded Sensor – NTC Temperature

Thermistors are temperature-sensing elements made of semiconductor material that has been sintered in order to display large changes in resistance in proportion to small changes in temperature. This resistance can be measured by using a small and measured direct current, or dc, passed through the thermistor in order to measure the voltage drop produced. These solid state temperature sensors actually act like electrical resistors that are temperature sensitive. That is where the name, a clear combination of the words thermal and resistor, comes from. Ametherm specializes in NTC, or negative temperature coefficient, thermistors.

Read more… →

Embedded Sensor – Passive Infrared Sensor (PIR)

  • PIRPassive InfraRed Sensor
  • PIR consists of a Pyroelectric sensor which generates energy when exposed to heat.
  • The module covered with Fresnel Lense Cover.
  • BISS0001 micro Power PIR Motion Detector IC.

Infrared Application

  • Passive Infrared Detector for Anti Theft security alarm system.
  • Passive Infrared Detector based Light On/OFF.
  • Automatic Light  ON/OFF.
  • Many other motion Detection Application.

Different PIR Modules

The HC-SR501 PIR Sensor Module

  • Working voltage : 5v to 20V DC
  • Range : 3 to 7 meters
  • Induction Lens size: 23mm.
  • PCB Size: 32mm x24mm.
  • Pins Details
    • Ground pin
    • VCC pin
    • The output pin detects an object when it is at a high logic level.
  • Two potentiometers.
    • One for adjusting the sensitivity of the sensor
    • Adjust the time for the output signal to stay high when an object is detected from 0.3 seconds up to 5 minutes.
  • Jumper Settings (Selecting the trigger modes)
    • non-repeatable trigger – when the sensor output is high and the delay time is over, the output will automatically change from high to low level.
    • Repeatable trigger –  will keep the output high all the time until the detected object is present in sensor’s range

Arduino Example code :

Circuit

Code

/* Arduino PIR Motion Sensor Tutorial */
/* www.ArunEworld.com */

int pirSensor = 8;
int relayInput = 7;

void setup() {
  pinMode(pirSensor, INPUT);
  pinMode(relayInput, OUTPUT);
}

void loop() {
  int sensorValue = digitalRead(pirSensor);
  if (sensorValue == HIGH) {
    digitalWrite(relayInput, LOW); // The Relay Input works Inversely
  }
}

Code Explanation

This Arduino code is for a PIR (Passive Infrared) motion sensor setup, where a relay is controlled based on motion detection. Here’s an explanation of each part:

SectionExplanation
CommentsThe code includes comments providing information about the purpose of the code and its source.
Variable DeclarationpirSensor = 8;: Declares a variable pirSensor and assigns pin 8 to it for reading the PIR sensor’s output. – relayInput = 7;: Declares a variable relayInput and assigns pin 7 to it for controlling the relay.
Setup FunctionInitializes the pins: – Sets pirSensor pin as INPUT to receive data from the PIR sensor. – Sets relayInput pin as OUTPUT to control the relay.
Loop Function– Reads the digital state from the pirSensor pin to check for motion detection. – If motion is detected (sensor value is HIGH), it turns on the relay by setting the relayInput pin LOW.