In recent years, wearable sensing devices have increasingly spread in people’s lives, enabling real-time monitoring of users’ conditions relatively to the health status, physical activity, and much more; some of the peculiarities of such devices are their flexibility, very low cost and power dissipation, wireless connectivity, reduced invasiveness, manufacturing simplicity, and multifunctionality. Specifically, the development of wearable or implantable human sensors for medical diagnostics and sport activity control covers several research fields, such as body-sensors for the detection of different biomarkers such as glucose, lactic acid, pH or cholesterol, as well as for monitoring biophysical parameters such as heart rate, temperature, breath rate, walk or body posture monitoring, fall detection, muscle contractions, etc. Further, 3D printing technology can be employed for the development of new wearable and flexible sensors, taking advantage of its simplicity, low cost, rapidity, and ability to reproduce complex geometries. These 3D-printed flexible electronic devices can be applied widely in the fields of personal wearable devices, prosthetic organs for the disabled, and human–computer interfaces. All these sensors need a suitable electronic conditioning section for impedance matching and adapting the characteristics of the signal provided by the sensor to the designed acquisition system. Finally, in this field, research activity concerns the development of new materials and sensing methodologies for the design of new wearable or implantable sensors of a new generation as well as the use of new energy harvesting techniques to make the devices energetically autonomous.
Summing up, this Special Issue “New Sensors and Flexible 3D-Printed Devices for Human Activity Monitoring: From Materials to Electronic Conditioning” aims to bring together innovative developments and synergies in the following topics (without being limited to them):
Wearable sensors for biophysical parameters;
SoC for health monitoring applications;
Biomarkers for biofluid detection (sweat/saliva/interstitial fluids/tears);
Less battery-implantable devices;
3D printing technology applied to wearable sensor development;
Flexible sensors and actuators for wearable devices;
Soft electronics for the signal conditioning applied to wearable sensors;
Smart prostheses and artificial organs;
Charging methods for implanted devices;
Energy-harvesting techniques for wearable/implantable body devices;
Low-power electronic solutions for signals acquisition/processing from wearable sensors;
New materials and sensing methodologies;
Software development for wearable sensors and body sensor networks.