Wing-App Portfolio Link
^The portfolio goes through my PDS and what development I’ve made to my product in order to meet the specification points. Due to the pandemic, there were difficulties reaching the full development potential of the product due to the limitations but some features were able to be developed as seen by clicking the link to the portfolio
Prototyping
Due to the constraints of working from home and going through a pandemic, I was unable to create physical prototyping for the wearable device. The device is an add on product and the app is the main result of this project.
However, to validate the feature of the wearable device, I have looked into the Fitbit as it is a similar product and can help outline the function of the designed wearable device I have done.
Much like the Fitbit, one of the most important functions of the designed wearable device is to be able to track the user’s heart rate, as this is needed to allow the automatic heartbeat-like vibrations to switch on in order to relieve the user of a panic attack.
The Fitbit is able to measure the heart rate of the user on their watch by using a technology called PurePulse. PurePulse was inspired by photoplethysmography where a tiny sensor was clipped to the finger to measure the heart rate, but it went through much refinement in order to track the heart rate on the wrist. Photoplethysmography is simply using light to measure blood flow.
When there is an increase in heart rate, the capillaries expand as the blood volume increase as well. Blood is able to absorb green light, hence if the blood volume is higher the more green light that is absorbed.
The Fitbit uses an optical heart rate sensor that can detect a range of 30-220bpm to then flash its green LED numerous times per second to the use of light-sensitive photodiodes to sense any volume changes in the capillaries located on your wrist. Once this is registered the Fitbit then calculates the beats per minute (bpm) of the user’s heart. In addition to this, the optical heart rate sensor used infrared light to determine whether or not the device is being worn on the wrist which also improves the accuracy of the data being fed back.
Another relation from the Fitbit to my device is that they both need to sync the information on the device to the app. Syncing is what allows for the data collected on the wearable device to be transferred and displayed on the app. The Fitbit devices use Bluetooth Low Energy (BLE) technology to sync their devices to phones, tablets, and computers.
BLE has a much lower power consumption in comparison to normal Bluetooth. Due to the low power consumption of BLE, the allows any applications using it, to run on a small battery for up to four to five years. This can be advantageous to applications that only need to exchange small amounts of data periodically. Can be used for applications such as blood pressure monitors, industrial monitoring sensors. public transport apps and Fit-bit like devices including my wearable device. Utilizing a BLE as one of the components in my design will allow the device to transfer small amounts of data back to the app on lasting battery power at a more affordable cost.
