Design Project Three
Wearable Device
This was a very open-ended design project, with no previously-set end-user. This project truly got my team and I to think about the various ways that technology can be implemented in the medical field and all its different applications. My team and I had built an EMG sensor for paramedics to help notify them when they may be in danger of hurting their back while carrying heavy equipment, patients etc.
A Quick Summary
Overstretching and tearing the lower back muscles are common ways that cause back pain. One of the easiest ways to walk away with such an injury is heavy lifting. A variety of professions such as paramedics, nurses, construction workers and more must do this heavy-lifting as a part of their day-to-day tasks; many times, it can get to a point where it may cause injury. If untreated, injuries such as this may hinder workers from completing important tasks that are integral to their careers and general everyday lives. Thus, uFlexx helps alert the user when they are in danger of injuring themselves so that they may take necessary steps to relieve the stress they are placing on their lower backs. Essentially, the device can help prevent these individuals from harming themselves, improving the quality of their day-to-day life.
The device attaches on by an elastic belt mechanism around the waist, allowing users to easily equip the device. Additionally, there is a wrist-worn device that alerts the user when data is being collected and when it is calibrated correctly. A buzzer is located on the back of the wristband and buzzes when the data exceeds a threshold, alerting the user of a risk of a back injury. There are two EMG (electromyography) electrodes on the lower back muscles once the belt is placed on correctly. These evaluate muscle activity by measuring the action potential caused by muscle contraction. The device continuously averages 10 of out the most recent values to ensure measurements are accurate. This average value is then compared to the threshold value, which is essentially the measurement of muscle action that is considered dangerous. When this occurs, the buzzer will begin to beep once per second. When the average value continues to surpass this threshold for 3 seconds or more, the frequency of the beep will increase to 4 times per second, alerting the user that they are in danger of hurting their back, and it is best to drop what they are holding immediately.
Another important aspect to note is that not all of these individuals will have the same body type. For example, fat between the surface of the skin and the muscle can increase the amount of resistance (ie. distance and insulation) between the muscle and the electrodes, making the measurements less accurate. Therefore, for higher BMI (body mass index), a calibration step takes into account this resistance when averaging out the values. In this step, the device will calculate the user's BMI after taking input of the individual’s height and weight and will add a scaling factor to the average value mentioned earlier. This will ensure that the measurements are more accurate and that the device can be easily used by any individual, despite their body type.