Effective and low-cost gas sensor based on a light intensity analysis of a webcam image: Gas enriched polymers under high pressure

Abstract

Gas detection and monitoring play important roles in ensuring safety in many aspects of technology and industry. An effective and low-cost gas sensor with high performance was developed by using light intensity measurements from images. This simple technique is based on volumetric measurements of released gas combined with light intensity analyses of bright-water-level images by employing a webcam and diffusion analysis. The gas emitted from gas enriched polymers under high pressure reduces the water volume level in a graduated cylinder, producing measurable changes in the pixel distance in the webcam controlled with LabView software; this phenomenon allows for the detection and monitoring of the released gas concentration. As a result, the gas sensor responds instantly and measures the gas concentration from 1 part per million (ppm) to 1500 wt∙ppm with an adjustable sensitivity and measuring range. Additionally, various performance tests for polymer materials verify that the sensor has satisfactory reliability, a broad measuring range, and insensitivity against variations in temperature and pressure. The developed low-cost sensor is applied for the detection and characterization of any other gasses, such as He, O2, N2 and Ar, through simultaneous real-time monitoring and in situ measurements. The present developed webcam sensor is designed for application of pure gas at high pressure.