Design and Development of a Temperature and Pressure Transmitter Using a Laser-Induced Graphene Sensor

The design and development of a temperature and pressure transmitter using a laser-induced graphene (LIG) sensor represents a significant advance in precision measurement technology. LIG, characterized by its unique porous structure and tailored flaw engineering, exhibits exceptional electrical and thermal conductivity, high mechanical strength, and flexibility, making it ideal for highly sensitive sensing applications. In this study, a sensor was directly patterned with LIG on a flexible substrate to enable real-time monitoring of temperature and pressure changes. Temperature is measured through LIG's intrinsic resistance variation, while pressure is sensed via its enhanced piezoresistive properties arising from its engineered porosity and defect structure. A signal conditioning and processing circuit was implemented for calibration and data visualization, featuring a modular design that supports long-distance data transmission via a standard 4–20 mA current loop. Moreover, the LIG fabrication process is inherently simple, cost-effective, and environmentally friendly. The single-step laser-induced patterning method eliminates the need for high temperatures, chemical solvents, and complex processing, thereby reducing energy consumption, production costs, and environmental impact. This approach positions LIG-based sensors as a promising low-cost and sustainable alternative to traditional sensor technologies. Experimental results demonstrate high accuracy, fast response times, and low power consumption, underscoring the potential of LIG technology in next-generation industrial and biomedical sensing applications.