Home Monitoring System

Home Monitoring System:

Now, we cannot see and care our relatives all the time, so for that we can make one system in which we can monitor our elderly relatives. In this case we are going to take care about smoke detection, temperature and humidity of the room, fire in the room, doorbell monitoring and carbon monoxide detection. So here we are going to monitor these 6 things for our elderly relatives.

Components Used:

1) Raspberry pi:

This is the latest version of raspberry pi. In this we have inbuilt Bluetooth and wi-fi, unlike previously we have to use Wi-Fi dongle in one of its usb port. There are total 40 pins in RPI3. Of the 40 pins, 26 are GPIO pins and the others are power or ground pins (plus two ID EEPROM pins.) There are 4 USB Port and 1 Ethernet slot, one HDMI port, 1 audio output port and 1 micro usb port and also many other things you can see the diagram on right side. And also we have one micro sd card slot wherein we have to installed the recommended Operating system on micro sd card. There are two ways to interact with your raspberry pi. Either you can interact directly through HDMI port by connecting HDMI to VGA cable, and keyboard and mouse or else you can interact from any system through SSH(Secure Shell). (For example in windows you can interact from putty ssh.) Figure is given below

2) Smoke Sensor (MQ-2):

The MQ-2 smoke sensor is sensitive to smoke and to the following flammable gases:

LPG, Butane, Propane, Methane, Alcohol, Hydrogen.

The resistance of the sensor is different depending on the type of the gas. The smoke sensor has a built-in potentiometer that allows you to adjust the sensor sensitivity according to how accurate you want to detect gas.

3) Carbon Monoxide Sensor (MQ-7):

This Carbon Monoxide (CO) gas sensor detects the concentrations of CO in the air and outputs its reading as an analogue voltage. The sensor can measure concentrations of 10 to 10,000 ppm.The sensor can operate at temperatures from -10 to 50°C and consumes less than 150 mA at 5 V.

4) Flame sensor:

Flame Detection Sensor Module is sensitive to the flame, but also can detect ordinary light. Usually used as a flame alarm.

Detects a flame or a light source of a wavelength in the range of 760nm-1100 nm. Detection point of about 60 degrees, particularly sensitive to the flame spectrum. Sensitivity is adjustable, stable performance.

5) DHT22 sensor:

The DHT22 is a basic, low-cost digital temperature and humidity sensor.

It uses a capacitive humidity sensor and a thermistor to measure the surrounding air, and spits out a digital signal on the data pin (no analogue input pins needed). Its fairly simple to use, but requires careful timing to grab data. The only real downside of this sensor is you can only get new data from it once every 2 seconds, so when using our library, sensor readings can be up to 2 seconds old.

6) Door Bell (Push Button):

Here we are using Push Button just to represent our door bell.

7) PCF8591 Module: In this project we are using 3 analogue sensors. As raspberry pi doesn’t contain analogue inputs so for that we need to use one ADC module. Here we are using pcf8591 ADC module

The PCF8591 is a single-chip, single‑supply low‑power 8‑bit CMOS data acquisition device with four analogue inputs, one analogue output and a serial I²C‑bus interface. Three address pins A0, A1 and A2 are used for programming the hardware address, allowing the use of up to eight devices connected to the I²C‑bus without additional hardware. Address, control and data to and from the device are transferred serially via the two-line bidirectional I²C‑bus.

Working of Project:

Here we are interfacing raspberry pi with smoke, co, flame, dht22 and push button. Here smoke, co and flame are analogue sensor and dht22 is digital sensor. As we all know that raspberry pi doesn't have analogue input pins so that's why for that we need to use one analogue module externally. And for that here we are using pcf8591 module which works on I2C. So first of all we need to connect all the components properly. In the next step you can go through our circuit diagram and connect your circuitry like that. After successfully making the connection it is time to do some coding part.

As we are monitoring 6 things so how we are monitoring that is the most important thing. So here we are using one pushbullet app, so whenever smoke will reach above the threshold value whatever we set so immediately we will get the notification in our smart phone through pushbullet app, same thing will work with other sensors like carbon monoxide, flame, dht22 and door bell. So whenever any of these sensors value will reach above the threshold value, immediately we will get the notification in our smartphone and then we can take care of our elderly relatives.

How to install Pushbullet:

Firstly You need to register in Pushbullet account for notification. Go to this link

https://www.pushbullet.com

You can register through either Google or Facebook.

In my case, We are using Gmail Account.

After successfully signup, log in and go to

Settings –> Account to create an API access token.

Circuit Diagram of Project:

Code of project: