Step Counter using MicroBit

Goal:

• Make a DIY Walking Step counter to help people quanitify number of steps walked in a given duration.
• Develop a simple UI by which one can understand the Steps done and progress bar for this goal, instead of waiting for a scrolling screen showing count.
• Capability to incorporate BLE to transmit data and enable IoT and data loggging.

User Interface :

Being a fan of "The best interface is no interface", I was more driven towards making a more simpler interface to get insights of progress instead of interfacing with the device specific time duration to get the reading.

Microbit consists of 25 SMD LED which I thought of making use of and thus, we can use these LED to show progress. Every LED shows 4% progress.

Lets say if the goal is 5k steps. In this case, for every 200 steps done, one LED will starts to glow. As we progress for every 1000 steps you would see one row fully ON and later starts filling up the next column. Personally, I felt very encouraging seeing LED going on for every small progress and felt kind of encouraging.

Data visualisation:

The device Reads Acceleration sensor data at ~10Hz and was able to give clear marking of movement and no movement data.

As you can see, a delta change in X axis accelerometer can be considered as lifting of leg action and thus, I decided to go with a threshold of 100, it is neither too sensitive causing false triggers nor caused errors in sensing the foot lift events.

Power backUp:

The device is powered up using 2x 1.5V AAA batteries and with this it is expected to last for a month. The brightness of LED can be reduced more in order to get long lasting performance.

How to make your own version of this project :

• Get microbit V1.5 hardware.
• Install GNAT community IDE with x86 compiler and ARM compiler
• Download Ada_Drivers_Library and the project repository mentioned below from github.com
• Place the Project repository inside Ada_Drivers_Library/examples/microbit/ folder.
• Open the project in GNAT Studio.
• Compile and Flash the project to the device and enjoy quantifying yourself with ada.

Challenges:

Started with microbit v1.5 and thus no ready made library was avaiable to interface with LSM303AGR sensor. Wrote a custom interface backward compitible with MMA8653 driver.