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Workflow of recycling 18650 battery cells

Recently I started involving in a project which requires me to explore the idea of building battery packs for battery powered sensor node (another story for another day). For cost reasons, I decided to explore the feasibility of reusing 18650 lithium ion cells from old laptop battery. Today, I’d like to briefly share the workflow I’m practicing to […]

Review of the Sharp Dust Sensor (GP2Y1010AU0F)

As part of my ambition to monitor the home ambience, I’d like to quantify “air pollution”. As usual, I’m not willing to shell out for than a few dozen bucks for a dust sensor. There are several cheap particulate matter detector (commonly known as dust sensor) that’s available in the market, such as the Shinyei […]

Facial Detection and Recognition with OpenCV and AWS Rekognition

Facial recognition for authentication (e.g. unlocking the door) is deemed not secure as many implementations are easily fooled. However, it is acceptable to use facial recognition for monitoring. In the future, I’d like to monitor movement at the front door for 2 reasons: detecting suspicious character and detecting if family member (or friend) is at the […]

Building an Ambience Monitoring Sensor Node with ESP8266

Monitoring Power Consumption with CT Sensor

Having the capability to monitor power consumption is definitely nice-to-have and plays an important role to reducing energy bill. Since some time ago, I’ve been looking for off-the-shelves wireless solution/product, such as these: https://www.amazon.com/P3-P4220-Wireless-Electricity-Sensor/dp/B0041W91GM https://www.amazon.com/Insight-Switch-Control-Lights-Appliances/dp/B01DBXNYCS However, looks like they are not something I’m willing to pay that kind of price, especially if I need multiple units – […]

Why ESP8266 and PlatformIO?

Today, I would like to address a question that I’m often asked: “Why do you not use Arduino Board (e.g. Uno, Nano) instead?“. This is referring to the sensor nodes I’ve deployed around the house. I’ll also describe the toolchain I’m using for development and OTA firmware update. Why not Arduino Uno/Nano/XX? My first sensor […]

Streaming Sensor Data (Raspberry Pi) to AWS IoT

In my opinion, the quickest way to monitor the ambience (e.g. weather station) is to deploy a sensor node and have the data streamed to a cloud platform that provides a nice dashboard. Sure, we can use platform like ThingSpeak that provides fuss-free all-in-one solution. However, I always prefer to use a generic cloud platform which allows […]

Android Things on Intel Edison

Electronics Buying Guide – Where to purchase online?

You may have some crazy idea which you’d like to prototype, or just wanting to learn a thing or two about hardware, but you’re clueless on where to purchase the necessary parts. This is for you – suggestions on where to purchase materials online, especially electronics components. May not be applicable to those residing outside of […]

Bluetooth Beacon and Google Physical Web