DIY Fitness Tracker Smart Watch with Oximeter and Heart Rate

Hey, what's up, Guys! Akarsh here from CETech.

Today we have with us some of the sensor modules that are very useful in our day to day life but in a tiny version of themselves. The Sensors that we have today are very small in size compared to the traditional big sized sensor modules that we use with the Arduino but they are as good as their bigger version.

With the help of these tiny and compact components from TinyCircuits, we are going to build a Fitness Tracker of our own that will have an oximeter, accelerometer, and a tiny OLED display as well.

So let's move to the fun part now.

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Tiny Modules From TinyCircuits

The Components that we have today in their tiny version are listed below:-​​

• ASM2022(Tiny Screen+): This is going to be the heart of the projects that we are going to make with the Tiny components. It will do the similar work that an Arduino or ESP8266 does in a circuit. It is a tiny OLED screen that can be connected using USB. It has a 32-bit processor and comes preloaded with a Flappy Bird Game which you can play using the buttons on the module. It is a Coloured display with 16-bit color depth. For using it in our project we need to configure it first which we will be doing in the further steps.

• ​ASD2123-R(TinyShield Wifi Board): It is a Module that is similar to the ESP8266 module it makes the project capable of connecting to Wi-Fi.
• ​AST1024(TOF Sensor Wireling): It is a Time of Flight Sensor which is required to calculate the time required by an object to cover a particular distance. Here we are using the term wireling because the modules are not required to be soldered they can be connected to each other using the connectors present on them or with the help of wired connectors that come with them.
• ​AST1042(0.42" OLED Screen): It is another OLED display but this time it is a more time one almost the size of our fingertip. It is a black and white display that can have many applications but in this project, we are not going to use this one.
• ​AST1037(Moisture Sensor Wireling): It is a tiny moisture sensor and its operation is the same as the bigger moisture sensor. It can be used to build a Plant Tracker.
• ​ASD2201-R(TinyShield MicroSD Adapter): As its name says it is a MicroSD Adapter with the help of which we can connect an SD card with our project in order to store data.
• ​AST1030(MEMS Microphone Wireling): This Wireling uses the SPW2430 MEMS Microphone to detect sound and output an analog signal.
• ​ASD2022(Wireling Adapter TinyShield): This is a kind of breakout board for our OLED display module. When connected with this, The connection ports are separated, and connecting it with multiple modules becomes easy.
• ​AST1041(Pulse Oximeter Sensor Wireling): It is the Sensor module that measures the heart rate or pulse and also gives the Oxygen level with the help of the Oximeter in it.
• ​AST1001(Accelerometer Wireling): It is the sensor module that gives the data about the position of any object. We are going to use this in our project to work as a step counter by sensing the change in position.
• ​AST1013(LRA Driver Wireling): It is basically a motor driving module that can be used as a vibrator motor signaling any notification.
• ​5 Wireling Cables of different lengths: These are wires of 5 different lengths that are used to connect different modules to the Adapter Shield and ultimately to the TinyScreen+.

Building Fitness Tracker: Hardware Part

Now we are going to build our fitness tracker project. In this step, we are going to connect all the suitable modules that are required for the fitness tracker to function. I suggest you check out the video for this project before doing the connections as it will help you understand the connections better.

Components Required: ASM2022(Tiny Screen+), ASD2022(Wireling Adapter TinyShield), ASR00007(Lithium Polymer Battery), AST1041(Pulse Oximeter Sensor Wireling), AST1001(Accelerometer Wireling), AST1013(LRA Driver Wireling), AST1030(MEMS Microphone Wireling), ASD2201-R(TinyShield MicroSD Adapter)

Steps to do the connections are as follows:-

• Take the Wireling Adapter TInyShield and Connect the Pulse Oximeter to the Port 1 of the Adapter Shield through the wired connectors.
• Connect the LRA Driver module to Port 2 and Connect the Microphone Module to Port 0.
• Connect the Accelerometer Module to Port Number 3. In this way, all the modules required are connected with the Adapter Shield in no time.
• Now connect or stack the Adapter Shield with the Tiny Screen+ and after that connect the MicroSD Adapter to the stack up.
• In the end, Connect the Lithium Polymer Battery with the Tiny Screen+, and in this way you are done with the Hardware Part of the Project in no time.

Now we have to configure the Arduino IDE to program the Tiny Screen+ to work as a Fitness Tracker instead of working in the Flappy Birds mode which we will be doing in the next step.

Setting Up the Arduino IDE

As we are working with the Tiny Screen+ for the first time, we need to install the suitable boards and libraries to make it work. For that you need to follow the steps given below:-

• Open the Arduino IDE. There you need to click the file button. From the dropdown menu that opens up, Go to Preferences.

• There you will see a field saying Additional Boards Manager URL. In that field, you need to paste the link given below separated by a comma: http://files.tinycircuits.com/ArduinoBoards/package_tinycircuits_index.json
• Once that is done, we need to go to Tools then Boards, and from there head over to Boards Manager.
• In the Boards Manager, we need to search for the "Arduino SAMD" Boards and Install them. When the Arduino SAMD boards are installed, We need to install the "TinyCircuits SAMD" boards as well.

• Now as the Boards are Installed, We need to install the TinyScreen Library. For that, head over to Sketch then Include Library, and then Manage Libraries. There we need to search "TinyScreen" and Install the library. You can also download the Library from the Github page of this Project and paste that into your Arduino libraries folder.

So in this way, we are done with the setup of our Arduino IDE. Now we are ready to connect the TinyScreen to our PC and upload the code for the project.

Building Fitness Tracker: Software Part

As we are done with the Arduino IDE setup and the Connections part for the project. Now we can do the Software Part of the Fitness Tracker build i.e. Uploading the Code to the TinyScreen+. For that we need to follow the steps given below:-

• Head over to the Github Repository of the Project from here.
• From there you need to download the MAX30101 library, Wireling library, and the SD Card library and put them in the Arduino libraries folder on your PC.

• After that, you need to download the Fitness Tracker file from the Github page. It is the Code for this project. Open that in your Arduino IDE.
• After opening the code. Connect the Tiny Screen+ to your PC. Select the correct COM Port and hit the upload button.

So in this way, We are done with the Coding part of the project as well. Now as soon as the code gets uploaded, Our Fitness Tracker will be ready to use.

Testing the Fitness Tracker

When the code is getting uploaded, The Screen displays Tiny Screen+ Bootloader mode and when the code gets uploaded, The Screen will become blank this means that the code is uploaded and now we are ready to use our fitness tracker. To start operating the Tracker, we need to press the button on the screen once. As soon as we press the button on the Screen, The Fitness Tracker will start its operation and the screen will start displaying various data such as the date, time, Pulse rate, Oxygen level, battery level, and Step Count. The screen may display a false step count or wrong count as the code was designed in such a manner that it counts a step even when there is a slight jerk.

We can modify the parameters in the code in order to make it more accurate. To check the Oxygen level and pulse rate. We need to take the Oximeter sensor and place it between our finger and thumb and the Screen will display the Readings. The readings are also stored in an excel sheet format in the SD card that we connected with the Tiny Screen and those readings can be checked by connecting the SD card to our PC through an Adapter. We can also connect the Wifi Shield with the project and upload the data to the cloud.

So you can see that the possibilities are many. You can build a number of projects from these components without any hassle of soldering. Some of the projects that can be made by these components are also there on the TinyCircuits website you can check them out and make them on your own.

So this was the Fitness Tracker project Tutorial. Hope you liked it.