Vital Jacket review¶
Hardware¶
Product overview¶
The Vital Jacket is a comfortable and easy-to-wear T-shirt that combines the latest textile technology with a built-in heart monitor, acquiring data at 10Hz. By allowing to do a continuous and noninvasively Electrocardiogram (ECG) acquisition combined with heart rate measurements, the device enables physicians to evaluate possible heart conditions when the user performs some sort of exercise. The system features the transmission of the data wirelessly via Bluetooth or it stores it locally on an SD card. This system is capable of continuously recording up to 72 hours of ECG data allowing physicians to make a more correct and assertive diagnosis of possible cardiac conditions.
Fig 1. Vital Jacket consumer kit available at http://www.vitaljacket.com/en/sdk-2/
As depicted in Figure 1, the product's kit includes a T-shirt, an electronic device, a battery charger, an SD card, and a set of electrodes. The product is available in two forms regarding the number of springs available on the T-shirt to which the electrodes are connected to, namely the 1L version which has 3 springs, and the 5L version which has 5 springs.
The usage of each version depends, logically, on the type of use required. The 5L version is more precise and therefore can be used for more subtle heart conditions such as arrhythmia screening. In contrast, the 1L is better suited for long-term monitoring, high-throughput training situations, or cardiac rehabilitation. This means that the 1L version can only detect more serious cardiovascular conditions, functioning more as an event detector where the cardiologist can not only analyze all events marked by the patient but also possible asymptomatic periods throughout an entire stroke. However, because it records only one channel, the 1L version can save up to 5 days of continuous data locally.
Device setup¶
- Clean with alcohol and dry very well the zones of the body where the electrodes will be placed. The electrode placement must follow Figure 2 for the 5L (A) and 1L (B and C) versions.
- Fix the springs inside the T-shirt to the electrodes placed in your body. A click must be heard.
- Check that the electronic device has an SD card and afterward connect it to the plug inside the pocket of the T-shirt. A red light should start blinking signaling that the device is working.
- Place the electronic device inside the pocket with the red light facing outward and close the pocket. The VitalJacket is now working and acquiring the ECG signal. In the center of the electronic device, there is an event button that allows one to switch it on or off.
Fig 2. Electrode placement of the 5L (A) and 1L (B and C) versions.
Color coding of the device¶
The electronic device displays 3 different colors depending on the information that it tries to transmit to the user:
Red light (Working mode):- Blinking normal (1 time per second) - the device is acquiring the signal and writing the corresponding data in the SD card.
- Blinking fast (3 times per second) - the device is acquiring the signal but is not recording data because the SD card is full.
- Not blinking - remove the SD card from the electronic device and put it back again.
- Slow blinking (1 time per 5 seconds) - battery under 30%.
- Standard blinking (1 time per second) - battery under 15%.
- Fat blinking (3 times per second) - battery under 5%.
- Light on - battery charging, when the light turns off the battery is fully charged.
- Standard blinking (1 time per second) - Bluetooth is active but is not connected to any electronic device.
- Blinking 5 times and from then blinking slowly (1 time per 8 seconds) - Bluetooth is on and the electronic device is empaired with another device.
Technical spcifications¶
The hardware and communication specifications can be visualized in the tables below (Figure 3):
Fig 3. Technical and logger unit specifications of the vital jacket hardware.
Troubleshooting tips¶
Figure 4 depicts some of the main problems encountered when using the device and their corresponding causes and solving tips.
Fig 4. Troubleshoot guideline.
Software Development Kit (SDK)¶
The Vital Jacket is also accompanied by software tools that provide integration possibilities into new prototypes and products, namely a Software Development Kit (SDK) and an Application Programming Interface (API) for different programming environments with drivers and sample code. The programming environments supported are Windows, Linux, Matlab, and Android, with the latter being of our particular interest due to providing integration with AndroidStudio for the App development. The Android package includes a data processing library (BioLib.jar) with a QRS detector algorithm and a file with a sample of code (TestBioLib.apk). This provides a stream of a set of control parameters that can be used to develop the Step-N-Count app. The data that can be streamed to AndroidStudio is represented in Figure 5.
Fig 5. Data parameters received from the VitalJacket device.
NOTE: The QRS detector algorithm is based on the paper (https://ieeexplore.ieee.org/document/4122029)
[1]https://www.vitaljacket.com/en/
