Brush painting all-carbon wearable dual temperature and strain sensor for human health monitoring

Simple, cost effective, wearable and multifunctional health monitoring sensors are essential to improve the standard of living and quality of health in developing countries, especially in remote and rural communities. This paper presents a facile, low cost, environment friendly, wearable all-carbon dual temperature and strain sensor for health monitoring. The dual sensor is fabricated by painting conductive paste on flexible sticky-note paper. The conductive paste is prepared by mixing pencil graphite and ink from the gel pen. Resistive temperature sensor is painted on the one side of the paper while comb like capacitive strain sensor on the other side of the paper. The response of temperature and strain sensors is insensitive to each other. The strain sensor is successfully tested to detect deformation in different body parts like knee, elbow, finger and wrist. This dual-sensor can be used as a pedometer after integration on the knee, as a gesture sensor after integration on the finger. It can also be used as a touch sensor, rehabilitation sensor and body temperature sensor.