ABSTRACT
The history of the industry has been undergoing many changes,
improving production methodologies and setting new goals. The
industry is currently facing a new challenge called Industry 4.0.
This is the result of technological developments in areas such as
the Internet of Things (IoT), Information and Communication Technology
(ICT) and Automation Systems. The goal is to define a
more dynamic and efficient production line, improving production
in terms of resources and time. However, in the current scenario,
there are some difficulties to overcome. One of these difficulties
is the existence of various communication protocols, being many
proprietary and closed, which hinders the interoperability between
machines. For this reason, there is a need to standardize communication
protocols, facilitating the integration of all elements in the
production line. Given this context, this paper presents the integration
of the MQTT protocol with the ROS tool to control a robotic
arm viaWeb. The angles of the robot links movements are informed
via web interface. The interface communicates with the robotic arm
via the MQTT protocol. The arm control software was developed
using the ROS tool as well as its simulation environment. The software
is implemented on the Raspbarry PI 3 development board and
the robot servo motors are driven by the Arduino Mega kit processor.
Data exchange between these elements is done through serial
communication. Tests were designed to assess communication latency
to validate the feasibility of using the MQTT protocol for this
scenario. The tests proved that the latency average of the MQTT
protocol, considering the worst case scenario, was 300 milliseconds,
which is within the range of the studies consulted in the literature.