Data Communication Based on MQTT in a Polymer Extrusion Process

Summary

This work proposes a flexible method for data communication between a film extrusion system and monitoring devices based on a message protocol called Message Queuing Telemetry Transport (MQTT).

Abstract

This work aims at building a flexible data communication structure for a polymer processing machine by employing a publisher-subscriber based protocol called Message Queuing Telemetry Transport (MQTT), which is operated over TCP/IP. Even when using conventional equipment, processing data can be measured and recorded by various devices anywhere through an Internet communication. A message-based protocol allows flexible communication that overcomes the shortcomings of the existing server-client protocol. Multiple devices can subscribe to the processing data published by source devices. The proposed method facilitates data communication between multiple publishers and subscribers. This work has implemented a system that publishes data from the equipment and additional sensors to a message broker. The subscribers can monitor and store the process data relayed by the broker. The system has been deployed and run for a film extrusion line to demonstrate the effectiveness.

Introduction

In the wave of the 4th industrial revolution, the acquisition and monitoring of various processing data have become important tasks¹. In particular, improving the manufacturing process using process data and establishing efficient operation plans will be an important goal of all manufacturing facilities^2,3. Downtime can be greatly reduced if an alarm can be sent out of the factory or if predictive maintenance can be performed in time⁴. Recently, many efforts have been made for data analyses in polymer processes^5,

Protocol

1. Broker installation

NOTE: To monitor and record processing data via the Internet, a computer system that relays the data should be prepared. The system should be accessible from both the publishers and the subscribers as shown in Figure 2. Thus, it needs to have a public IP address that is known prior to any communication. An open MQTT broker called Eclipse Mosquitto is installed on the system¹³.

1. Connect a computer to the Internet giving a public IP address. Give the address in the IP setting of the operating system.
2. Install a broker sof....

Results

It has been found that the data shown in the HMI and measured by the Raspberry Pis were monitored and recorded in the subscribers as shown in Figure 5. As presented in the video, the processing data are logged into the database.

Discussion

By following the protocol presented, the processing data can be monitored and recorded without expensive IT solutions such as the MES. The IoT technologies can make it easier to acquire and deliver data from conventional machines. It has been shown that the message-based protocol, MQTT, successfully serves as a platform for data communication for polymer processing lines. Moreover, additional data can be flexibly measured and transmitted together. The additional publishers employed in this work were the Raspberry Pis. No.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Edge Device	Adavantech	UNO 420	Intel Atom E3815 Fanless
Film Extrusion Machine	EM Korea	Not Available	For production of 450 mm film
Pydroid	IIEC	Not Available	Android Devices
Python3	Python Software Foundataion	Not Available	Windows, Linux
Raspberry Pi 4	CanaKit	Not Available	Standard Kit