Desenvolvimento e avaliação de sistema internet das coisas para monitoramento de temperatura de equipamentos em unidades de alimentação e nutrição

Abstract

The IoT technology has enabled adding information systems throughout the food production chain, including food service (FS). However, the availability and use of this technology for temperature monitoring in FS, a critical point for guaranteeing the quality of the meals produced in these establishments, are still incipient. Therefore, the objective of this study was to develop and evaluate a low-cost open technology IoT system capable of automating the monitoring of temperature and humidity of different equipment present in FS. The study comprised the development of the complete infrastructure containing electronic devices to gather data from equipment, a secure network for data transmitting, a structure of cloud systems for data analysis, storage and feedback, and communication with users. The system was implemented in an FS and subsequently evaluated for 130 days for stability when in uninterrupted usage and user satisfaction. Its physical part was composed by the NodeMCU microcontroller with Tasmota 9.5.0.4 embedded, connected to the DS18B20 or AHT10 sensors (temperature and humidity). The Node-RED and Cloudant online services were maintained on IBM Cloud, while Mosquitto, Node-RED, and InfluxDB were maintained on AWS. Data were made available to users through a fixed instrument board consisting of a 10" monitor coupled to a Raspberry Pi 3B; a responsive web interface; an IoT MQTT Panel app, and the Telegram messenger (only for sending notifications). The devices have not failed, worked stably, and demonstrated to be physically robust during testing. The cost to implement and maintain the whole system in six different FS's equipment was BRL 2,064.44 (USD 392,96). In the four items evaluated by the users (the ease of access to information; notifications of incidents via smartphones; the benefits that the implementation of monitoring of this equipment brought to the activities developed; the deployed system global quality) 100% provided good feedback, being satisfied (average 34.55%) or very satisfied (average 65.45%). In conclusion, the whole system developed using IoT technology provided a lowcost automation tool for temperature and humidity monitoring in FS.