#dust sensor

Dust Sensor Industry 2021 by Market Analysis, Growth Opportunity, Future and Forecast to 2027

Market Overview The report captures the basic information pertaining to the Dust Sensor market along with the critical analysis of the core market factors. The overview highlights the definition of the industry offerings and their application in varying end-user industries. A thorough analysis of the manufacturing and management technology has been presented as well. The integrated report on the…

In this part we will review simple Arduino program that is designed to read analog signals from Arduino A0 port and converts them to dust pollution level in milligrams per square meter. That program is far from final solution, but is good to have basic understanding of data sampling.

Control principle

According to specification for GP2Y1010AU0F  

we need to perform following steps to do sampling measurement:

Enable the internal infrared emitting diode by setting the pin ILED to HIGH. 

Wait 0.28ms, then the external controller starts to sample the voltage from the pin AOUT of the module. Notes that the output wave will take 0.28ms to reach steady state after the internal infrared emitting diode is enabled. 

There is a period of 0.04ms for sampling. When finished, set the pin ILED to LOW to disable the internal infrared emitting diode. 

Calculate the dust concentration according to the relationship between output voltage and dust concentration. 

Arduino program

Lets create Arduino program to perform that steps:

We assume that ILED diode is connected to Digital output D7 and Analog output from sensor is connected to A0. So, we could configure it and switch off at program start:

#define PIN_LED   7 #define SENSOR_PIN 0 pinMode(PIN_LED, OUTPUT); digitalWrite(PIN_LED, LOW);

Now, during processor cycle we should turn on diode, wait 280 microseconds to warm-up, read voltage value from A0, wait 40 microseconds and switch-off the diode. After that we should sleep till next operation.

digitalWrite(PIN_LED, HIGH); // power on the LED delayMicroseconds(280); // wait to warm-up DUST = analogRead(SENSOR_PIN); // read data delayMicroseconds(40); digitalWrite(PIN_LED, LOW); // power off the LED

Serial.print( DUST ); delayMicroseconds(9680); // sleep till next iteration

That looks simple! But our printout will show some voltage data, that should be additionally calculated to mg/m3, otherwise it is hard to understand current pollution level.

After that calculation we could use following table as a reference to get pollution level:  US and Europe air quality standards   

http://arduinosensor.tumblr.com/post/134273104325/open-large-imageus-epas-aqi-and-europe-poland

So in next post I am going to more aspects related to pollution level calculations. 

In previous Part #1 I’ve described basics of Sharp Optical Dust Sensor. Now it is time to connect it to Arduino and run the code, to read sensor data and convert it to useful format.

I’ve bought cheap and small Arduino Nano board, breadboard and bunch of wires because I don’t like to spend time with soldering. I am going to build prototype, and later create smaller solution with LCD panel, some buttons to change modes and batteries pack. 

I’ve got following solution, that could show some dust measurement results. I’ve spend a lot of time to proceed data, since that sensor produces analog signal of optical air measurement, and it should be converted to some useful units like milligrams per square meter. 

As I mentioned in previous Part #1 my goal is to measure PM2.5 & PM10 pollution. So 25 µg/m3 of PM2.5 is considered as 100% pollution value. And I want to know when level is more than 300% which is considered as unhealthy conditions and it is better to stay at home and not open the windows.

Since PM2.5 is more dangerous, I would like to be able to measure PM2.5 & PM10 separately. But unfortunately  GP2Y1010AU0F is unable to distinguish between different particles and shows general pollution level.

So, lets review how to connect  Sharp Optical Dust Sensor to Arduino Nano board and show data on computer, connected to Arduino Nano via USB cable. If you have some LCD display then we also could use that to show data and have mobile solution.

Components:

Arduino Nano board

Sharp Optical Dust Sensor GP2Y1010AU0F 

Waveshare  Dust Sensor connection board

Breadboard

Jumper cables

16x2 LCD Display (optional)

Fig 1 - Arduino Nano board

Fig 2 - Waveshare  Dust Sensor board with connected  GP2Y1010AU0F

Fig 3 - Breadboard

Sensor connection

Waveshare Sensor Board has 4 pin connector and is very easy to connect it to Arduino. 

Pin 1 VCC is connected to Arduino 5V pin. 

Pin 2 GND is connected to any Arduino ground pin.

Pin 3 AOUT (Analog Output) is connected to Arduino A0 pin.

Pin4 ILED (Infrared LED) is connected to Arduino D7 pin

Whole system is powered by mini USB connector that is located on Arduino Nano board. Waveshare  Dust Sensor board has red LED, that lights if power is connected to VCC.

In next Part #3 we will review Arduino program that is designed to read analog signals from Arduino A0 port.

Later we will convert analog data to pollution levels based on US and Europe standards.

Open this chart as large image in another post...

Go to next Part #3:    Arduino PM2.5 Sensor based on Sharp Optical Dust Sensor GP2Y1010AU0F

Atmospheric particulate matter – also known as particulate matter (PM) or particulates – is microscopic solid or liquid matter suspended in the Earth's atmosphere. They have impacts on climate and precipitation that adversely affect human health. The size of the particle is a main determinant of where in the respiratory tract the particle will come to rest when inhaled. Larger particles are generally filtered in the nose and throat via cilia and mucus, but particulate matter smaller than about 10 micrometers, referred to as PM10, can settle in the bronchi and lungs and cause health problems. PM2.5 leads to high plaque deposits in arteries, causing vascular inflammation and atherosclerosis – a hardening of the arteries that reduces elasticity, which can lead to heart attacks and other cardiovascular problems.

The European Union has established the European emission standards which include limits for particulates in the air:

PM10 - Yearly average 40 µg/m3

PM2.5 -  Yearly average 25 µg/m3

I am living in Krakow - Poland,  that is quite polluted city, especially by old-style charcoal heaters around the city and suburbs. In warm period there is no problem with pollution, it is around 60% for PM2.5 during the year. But in winter time pollution level could reach 800% and above.

In Krakow there are only 3 PM2.5/PM10 sensors that could be observed thru internet at http://aqicn.org/city/krakow. 

And they are far from my apartment, so I don’t know real level in my area. I’ve decided to build my own sensor, since I don’t like to keep window open or go ride bicycle at time when it is highly polluted outdoor.

I’ve researched several articles about Arduino based DIY sensors and decided to start building my own solution using cheap and well known sensor from Sharp -  GP2Y1010AU0F, that is an optical air quality sensor, designed to sense dust particles. An infrared emitting diode and a photo-transistor are diagonally arranged into this device, to allow it to detect the reflected light of dust in air. It is especially effective in detecting very fine particles like cigarette smoke, and is commonly used in air purifier systems. It generates an output voltage proportional to dust density.

There are some lenses inside, that could be vacuumed thru the hole, after some time, in case if dust appeared inside.

To connect it to Arduino you also need 220 uF capacitor and 150 Ohm resistor.

An important thing about the code in case if you will connect sensor to Arduino using schema above is that in order to turn the Infrared LED on, you have to digitalWrite LOW on LED input terminal. Because the transistor that opens the drain is PNP type of transistor which needs negative base voltage.

But also there are Arduino kits on market, that already have small board with some elements and connectors, to support Arduino. So you don’t need any additional details or soldering. You also could use HIGH signal on  digitalWrite to turn the led on and  LOW - to switch off. I found it useful, since that board support different voltage and has some circuits to improve connection & signal.

It costs about 15$

Next PART #2 will consider aspects of connecting and programming that dust sensor to Arduino Nano board.

Go to next part:    Arduino PM2.5 Sensor based on Sharp Optical Dust Sensor GP2Y1010AU0F

Collection of pollutants from diverse sources like emission from stoves and fireplaces, leads to air pollution within our homes. The most common air contaminants are inclusive of mold, radon, pollen, dust and chemical fumes. The effect of indoor air pollution is usually underestimated and air contamination is usually visualized as factories emitting black smoke or vehicles polluting the environment. Minute attention is given to the pollutants released by paints or pesticides. Without air filtration systems, it would almost be impossible to lead a healthy life.

Health drawbacks

About 70% to 90% of the American population spends their time indoors. More than 50% of the time, they spend time at home. People living within their homes may not know the side effects and health drawbacks they are exposed to. 87% of the Americans have no idea that their home environment is dirtier than the air outside.

Without the use of air filtration systems, the health drawbacks that drag you to the hospital include:

Coughs, flu, head-aches and sore throats; cooling and heating systems will increase the likelihood of health concerns like these. In addition, if there is no air filtration system installed, then coughs and flu can be contagious. It may spread from one family member to another. Symptoms more severe than this may include cancer, heart diseases and breathing problems.

Passive smoking has become a rising concern. Secondhand smoke has over 200 poisons with 43 compounds that cause cancer. So if you live with someone who smokes, then it is likely that secondhand smoke gets to you. Statistics reveals that passive smoking caused over 35,000 deaths through heart diseases while approximately, 3000 died of lung cancer. (Source: American Lung Association)

Improving air quality

The two most successful techniques to enhance the quality of indoor air are:

Air Cleaning

Air filtration systems are successful at enhancing air quality by absorbing pollutants. Usually, cooling and heating systems create contagious illnesses because pollutants are ventilated around the entire house. An efficient air filter will save you from discomfort and the hassle of falling sick.

Ventilation