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Hi all, in this instructable you will see how a smartwatch can be made using an Arduino board and a few other components. We are going to design and get a custom PCB fabricated which will be the motherboard of our watch housing the main circuit and the brain of the watch ATmega 328P which we will salvage from an Arduino Nano board.
I have chosen the Arduino Nano and not the more commonly used Arduino UNO because the Nano features a Surface Mount chip so it’s much more compact and in this project, space is key because we need to fit all the components in the least space possible.
I am going to use a 160 mAh Li-Po (Lithium Polymer) battery which will easily be able to power the watch on regular use for at least a week which is quite good enough. We will use a USB battery charging module for charging the battery. This will also have a USB port in it to charge the battery!
I have designed the body of the watch in a 3d design software and you can easily get it 3d-printed anywhere. This was we can keep the watch completely personalised according to your need. The watch will be activated by using a push-button present at the side of the watch.
The watch will have Bluetooth functionality and will be connected to an app that can be used to track data. It can count the steps, distance and the calories burnt using an accelerometer module. With the same components and in some iterations in the code and the app, we can also easily track messages and calls received on the phone through the smartwatch! The watch will also have a heartrate measuring sensor in it which will be able to measure your pulse and I have tried it out.It’s pretty accurate!
This was a little info about the project that we are going to work on. So let’s begin.

Components:

Arduino Nano
DS1302 Real Time Clock Module (Only the DS1302 chip needed)
TP4056 Battery Charging Module
ADXL335 Accelerometer Module
100K Value SMD Resistor
10K Value SMD Resistor
Pulse Sensor
USB to TTL Interface (For programming the ATmega 328P)
0.96 inch OLED Display
HM-10 Bluetooth Module
Tools:

Soldering Iron
Hot Air Soldering Station (for self-assembly)
A Set of Precision Tweezer Set (optional - makes picking components easy)
3D Printer (optional - can get it third-party 3D printed)
Precise Soldering Wire”

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