# Smart Clothing Framework for Health Monitoring Applications
## 2 Wearable Technology and Smart Clothing
### Computational Approach on Wearable Technologies  
#### 2.6.1 Sensor-Based Technology  
Current advances in low-power electronics and the miniaturization of sensors have paved the route for a wide range of wearable devices for the applications of monitoring health and fitness. Huge research and commercialization endeavours all over the world are concentrated on developing wearable biosensors that can randomly monitor biochemical markers in the human body for managing diseases diagnosis, prognosis, and monitoring of fitness [47], particularly for people in North America.  
[PERSON] et al. [48] have proposed an efficient cold-starting biofuel-cell-based energy harvester system, fabricated in 65 nm CMOS, which can perform a cold start-up with a low voltage (0.39 V) by employing a start-up enhancement block where a power efficiency of 86% is achieved. The outcome of this research is that the energy harvester chip can attain an enhanced efficiency with below 0.4 V of input voltage and 5.5 \(\mu\)W of average output power. However, the authors have not presented how to control oscillation failure at the lower supplies.  
A review on wearable electrochemical biosensors was conducted by [PERSON] et al. [47]. The authors have presented the current advancement and commercialization of wearable electrochemical sensors for measuring blood glucose levels to monitor dehydration in fitness applications. Although the authors have shown great prospects on wearable electrochemical sensors for both remote and personalized healthcare, they have not provided the recent advancements in and future of smart clothing.  
[PERSON] et al. [49] presented research work on flexible and fully integrated wearable biosensors for measuring glucose, lactate, sodium and potassium ions, and skin temperature. The signals are processed through a system interfacing with the skin with silicon integrated circuits merged on a flexible circuit board. The system is capable of measuring the detailed sweat profile of humans while they are doing both indoor and outdoor physical activities. The system is also capable of performing a real-time assessment of the physiological state through a mobile app connecting with cloud services. Although the system can be applied  
Figure 7: Summary of wireless communications technologies for smart clothing (information from [46]).  
in physiological monitoring applications, information on introducing smart clothing and a comprehensive framework for developing the smart clothing is not given.  
[PERSON] et al. [50] summarized the current advancements of skin-interfaced wearable sensors. The authors introduced the strategies of materials selection and structure design, which can enable the sensors to contact human skin. The authors have also classified and discussed physical and biochemical sensors. In addition, power issues, wireless communication and how to analyse the data are also discussed in their paper. Challenges and further opportunities are also identified by the authors for future wearable devices and systems. Although the paper has reviewed many key parts on wearable technology, a complete framework for developing smart clothing is missing.  
A microfluidic tactile diaphragm pressure sensor based on embedded Galinstan microchannels has been developed by [PERSON] et al. [51]. An embedded equivalent Wheatstone bridge circuit was used to take advantage of tangential and radial strain fields, where the sensitivities obtained were as high as 0.0835 kPa\({}^{-1}\) with superior response linearity. The bridge circuit provides built-in temperature compensation at temperatures of 20 and 50 \({}^{\circ}\)C without external offsets. According to the authors, the liquid-state diaphragm pressure sensors may be useful for monitoring pressure in various electronic skin and smart textile applications. However, a complete smart clothing framework has not been offered.