Using OPC UA for IoT-based Indoor Air Quality Monitoring and Control System

The main goal of this study is to design a monitoring and control system for air quality, the level of gases released in the environment, humidity and temperature based on the Internet of Things in industrial environments, which in addition to the cost-effectiveness of the proposed system in terms of energy consumption and cost, Improve the level of security in sending and receiving data. Another goal of this plan is easy access for end users to real-time data in environmental conditions. The general purpose of the proposed system is the ability to detect hazards, increase safety and productivity in industrial environments, and alert users and industrial owners if the data exceeds the limits defined by environmental standards. In order to achieve this goal, data protocols compatible with industrial environments and communication protocols with proper performance in data transmission, in the system of sensors based on the Internet of Things in similar ideas, with a focus on air quality monitoring and control, are investigated. As a result of comparing related articles, in order to implement the proposed idea, OPC UA data protocol and 4G LTE communication protocol have been used and the performance of the proposed system has been tested in an industrial warehouse under fire and clean air simulation. The results show that the idea of this research has better efficiency than similar studies in terms of two factors of energy consumption and the security level of sending and receiving data. For this purpose, the software infrastructure of the Internet of Things has been examined with the factor of information protection and increasing the security level in order to visualize environmental data. In the proposed monitoring and control system, from the Internet of Things platform on the cloud server side and Raspberry Pi board for control and measurement, the MQ2 sensor for detecting smoke and the concentration of LPG, alcohol, propane, hydrogen, methane and carbon monoxide gases, the MQ135 sensor is used to measure air quality and detect ammonia and carbon dioxide gases and DHT22 sensor to measure humidity and temperature, as well as a 4G mobile modem to load received environmental data on the clientside. In investigating the performance of the proposed system under fire simulation of wood, cloth and paper and clean air in an industrial warehouse for fourteen days, in two situations of Raspberry Pi board connected to 4G LTE and Wi-Fi modem, the fire simulation value has been given. Detected in Wi-Fi connection mode was lower than 4G LTE mode and lower than previously predicted, but finally compared to the results of seven days of testing for each connection mode including clean air and fire simulation recorded in Things Board cloud platform. Regardless of the minor differences, they are similar. The results show that the idea of this research has higher efficiency than similar studies in terms of two factors of energy consumption and the security level of sending and receiving data.