Raspberry Pi, Node.js and Twilio – Is It Raining Arvind? #IoT

Usually my mom dries the clothes on the terrace and whenever I am at home she keeps asking me to look outside and tell her if it raining or not. Literally every half an hour or every time she hears a swoosh or a woosh from outside.

I was fed up and wanted to eliminate the middle man (me). So I came up with an app. It is called “Is it raining Arvind?” (LOL I know) . All the app does is tell my mom if it is raining outside now. And when it starts raining, the app triggers a buzzer and sends an SMS to my mom. Smart right! And I was off the hook.

So, this is how the app works. It uses the conductive property of the water. There are 2 wires that are connected to the Pi between a GPIO pin and 5v. And when these 2 pins are connected, it triggers a High on GPIO pin. So, we place these 2 wires outside on the terrace inside a bowl. Once the bowl is filled with water because of the rain, the circuit is completed and a High is triggered on the GPIO.

We take advantage of the GPIO high and then trigger the buzzer and send an SMS using Twilio. Smart right!?

Below is a quick demo of the app

Sweet right!

You can find the completed code here.

So, let us get started.

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Raspberry Pi, 16×2 LCD and Node.js – Print stuff

In this post, we will interface Raspberry Pi and a 16 X 2 Liquid Crystal Display. And then we will write a Node.js program to print some information on the LCD using the lcd node module. We will see how to print a Digital clock, get the Pi’s IP Address and print the same and how we can interact with the world wide web and display the same on the LCD.

Below is a quick demo of how you can print stuff using a Web Browser

You can find the completed code here.

So let us get started.

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Raspberry Pi, Camera and Node.js – Live Streaming with Websockets #IoT

A few days ago Bala Kolluru has reached out to me asking if we can control a Raspberry Pi camera module using Web browser, so he can view a live stream from any HTML5 powered device. I was intrigued by this idea and wanted to give it a try.

In this post, we will see how we can implement a system that can “stream” a video from our pi to a browser. The completed system would look like

Pretty sweet right! I am able to see my aquarium from any where and check on my only gold fish. This can be extended to do anything.

For instance, you can hook the camera up pointing at the front door, as soon as someone rings the bell, you can see who is at the door by opening the video stream URL in your mobile/tablet/computer and confirm if you need to wear pants to open the door.

So let us see how we can build such an awesome multi-purpose system.

You can find the complete code for this system here.

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Raspberry Pi, Camera, Node.js – Video & Email The Intruder

In one of my earlier posts : Raspberry pi, PIR Sensor and Node.js – An IoT Intruder Alert system, I have shown how you can detect intruders with Raspberry Pi and a PIR sensor.  And once the intruder is detected, an email will be sent with the time of incident.

This is good but not that helpful. In this post, instead of just sending an email, we will record a video of the intruder as the “act” is performed and then attach that video along with the email. Sweet right!

Below is a quick demo that show how things work

The video is a bit fast and too shaky. So Let me quickly run you through it. First we start the node program. As soon as a intruder is detected, the buzzer gets triggered. At the same time, we start the recording on the camera. We record a video for 10 seconds and then start sending the same in an email.

Pretty sweet right!

You can find the completed code here.

So let us get started building this IoT Video and Email The Intruder system!

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Raspberry pi, PIR Sensor and Node.js – An IoT Intruder Alert system

In this post, we will build an Internet of Things Intruder alert system. This system uses a PIR Sensor along with the Raspberry pi. When the PIR Sensor detects a change in a given surrounding, it will trigger the Pi to send out an email to a user with the time of intrusion. Sweet right!

The final system would look like

You can find the completed code here.

So, let us get started.

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Raspberry pi, a Buzzer and Node.js – An IoT Doorbell

In this post, we will build an embedded system – A Doorbell, with Raspberry pi B+, A Buzzer and Node.js. This embedded system will act as both a normal Doorbell with a button switch and the same doorbell can be controlled over internet.  Simple right?

The final output of this embedded system would look like


The completed code can be found here.

So, let us get started.

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