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- Learning emergent digital technologies: the experience in the internet of things course unitPublication . Leitão, Paulo; Piardi, Luis; Sakurada, Lucas; Mendes, Andre C.Industry 4.0 is re-shaping the way companies and individuals operate, but it is also introducing strong demands in education processes to train professionals with adequate competencies in emergent digital technologies, e.g., Internet of Things (IoT), Artificial Intelligence and collaborative robotics. In the last decade, innovative educational methods are being applied, e.g., problem-based learning and project-based learning, to move the traditional education approach into a more student-centric process where the student has a more active role. Recent studies point out that the combination of such educational methods is beneficial, each one selected according to the particularities of the learning subject and objective. Having this in mind, this paper describes the application of a learning methodology that combines different educational methods, namely face-toface, problem-based learning and project-based learning, in a teaching course unit focusing on IoT technologies. The achieved results show an increase of the student’s assessment performance, motivation and satisfaction, and the opportunity to consolidate their acquired knowledge with hands-on practice. This approach also stimulates the acquisition of soft skills, mainly teamwork, communication, creativity and critical thinking.
- Indoor location estimation based on diffused beacon networkPublication . Mendes, Andre C.; Diaz-Cacho, MiguelThis work investigates the problem of location estimation in indoor Wireless Sensor Networks (WSN) where precise, discrete and low-cost independent self-location is a critical requirement. The indoor scenario makes explicit measurements based on specialised location hardware, such as the Global Navigation Satellite System (GNSS), difficult and not practical, because RF signals are subjected to many propagation issues (reflections, absorption, etc.). In this paper, we propose a low-cost effective WSN location solution. Its design uses received signal strength for ranging, lightweight distributed algorithms for location computation, and the collaborative approach to delivering accurate location estimations with a low number of nodes in predefined locations. Through real experiments, our proposal was evaluated and its performance compared with other related mechanisms from literature, which shows its suitability and its lower average location error almost of the time.
- Convergence of the Reinforcement Learning Mechanism Applied to the Channel Detection Sequence ProblemPublication . Mendes, Andre C.The use of mechanisms based on artificial intelligence techniques to perform dynamic learning has received much attention recently and has been applied in solving many problems. However, the convergence analysis of these mechanisms does not always receive the same attention. In this paper, the convergence of the mechanism using reinforcement learning to determine the channel detection sequence in a multi-channel, multi-user radio network is discussed and, through simulations, recommendations are presented for the proper choice of the learning parameter set to improve the overall reward. Then, applying the related set of parameters to the problem, the mechanism is compared to other intuitive sorting mechanisms.
- Towards distance teaching: a remote laboratory approach for modbus and IoT experiencingPublication . Carvalho, José Augusto; Mendes, Andre C.; Brito, Thadeu; Lima, JoséRemote laboratories are of extraordinary importance for students that cannot attend classroom lessons. Once Automation and industrial networks are topics of electrical engineering that should be studied and experimented with by students in a practical way, this paper presents a developed tool that students can use to access the laboratory equipment from outside. It has as an advantage the capacity of handling several students simultaneously, and it is accessible 24 h per day and 7 days per week. The proposed tool also allows students in the classroom to interact with the system. With this proposed tool, connections between Programmable Logic Controllers (PLC) with supervision and control of high-level systems such as LabVIEW IDE are possible to program and test. The hardware implementation in the laboratory can be accessed by students to control illumination, heating and window shutter, and sensors to acquire wind speed, temperature, humidity, and CO2, as examples.
- Cooperative awareness in cognitive wireless networks for jamming controlPublication . Mendes, Andre C.; Brandão, Diego; Diaz-Cacho, MiguelIn cognitive wireless networks, opportunistic network devices can be programmed to take advantage of licence holders' idle times and dynamically adjust their operating parameters to improve transmissions. For this to be successful, these idle periods must be reliably detected. To support this requirement, this work proposes a cooperative detection mechanism for the signals transmitted by the licenced system through the use of positioning-enabled devices. Such devices can provide information to guide and control opportunistic network devices to limit interference to the licenced system. Simulations show that keeping interference within specification limits makes it possible to maintain opportunistic network communications in an ad hoc scenario with quality.
- Sub-system Integration and Health Dashboard for Autonomous Mobile RobotsPublication . França, André Luís; Loures, Eduardo; Jorge, Luisa; Mendes, Andre C.Data visualization has become increasingly important to improve equipment monitoring, reduce operational costs and increase process efficiency with the ever-increasing amount of data being generated and collected in various fields. This paper proposes the development of a health monitoring system for an Autonomous Mobile Robot (AMR) that allows data acquisition and analysis for decision-making. The implementation of the proposed system showed favourable results in data acquisition, analysis, and visualization for decision-making. Through the use of a hybrid control architecture, the data acquisition and processing demonstrated efficiency without significant impact on battery consumption or resource usage of the AMR embedded microcomputer. The developed dashboard proved to be efficient in navigating and visualizing the data, providing important tools for the platform manager’s decisionmaking. This work contributes to the health monitoring of devices based on Robot Operating System (ROS), which may be of interest to professionals and researchers in fields related to robotics and automation. Furthermore, the system presented will be open source, making it accessible and adaptable for use in different contexts and applications.
- Analysis of topological characteristics impacting the allocation of controllers in an SD-WAN networkPublication . Padrenuestro, Vicente; Mendes, Andre C.Finding a viable and optimal solution to the Software-Defined Networks (SDN) controller allocation problem in an open SDN network is a challenging task. In this context, this work was developed to expose a network's real characteristics, which may impact the choice of positioning an SDN controller. Furthermore, the experiments with the Pareto-based Optimal Controller-placement (POCO) tool and with the ONOS and Floodlight controllers are shown, which served as a comparison to assist in decision-making regarding the best positioning of the controller within the network. In summary, the results showed that not only the static aspects of the network should be considered, but also the dynamic characteristics and aspects related to the model and the purpose for which the controllers are used, factors that can impact the positioning.
- Real airplane cockpit development applied to engineering education: a project based learning approachPublication . Carvalho, José Augusto; Mendes, Andre C.; Brito, Thadeu; Lima, JoséEngineering education, the process of teaching knowledge and principles to the professional practice of engineering, can be done by resorting to several methodologies. Project Based Learning is a teaching method that allows students to get knowledge and skills by developing and solving complex problems or challenges, supported by a supervisor. In the presented work, a real airplane cockpit development is used as a case study for Mechanical, Mechatronics, Electrical, and Computer Science courses. Students are encouraged to develop modules to be applied in the cockpit and further integrated with other ones.
- Integration of ROS navigation stack with dynamic environment information in gazebo simulationPublication . Mendes, Pedro Henrique Ferreira; Mendes, Andre C.; Duarte, Luis F.C.Sensing the environment is a crucial task that robots have to perform to navigate autonomously. Furthermore, it must be well executed to make navigation safer and collision-free. As autonomous mobile robots are being deployed in several applications, they often encounter dynamic habitats, where sensing and perceiving the environment becomes harder. This work proposes integrating a wireless sensor network with the Robotic Operating System to incorporate data into layered costmaps used by the robot to navigate, feeding the algorithms with advanced information about the territory. The architecture was tested in simulation, where we could validate the structure and collect data showing improved paths calculated and reduced computational load through better parametrization. Thus, this strategy ensures that the advanced information about the environment has improved the navigation process.
- Management of virtual environments with emphasis on securityPublication . Mendes, Andre C.With the popularity of using virtual environments, it urges important measures that increase its security, as well as maintain a good user experience. A widespread attack is a denial of service which proposes to break the availability of service through a large number of illegitimate requests employing all computing resources of the target and degrading the user experience. In order to be effective in this particular type of attack, usually powerful equipment or a combination of them is required. This article proposes a new approach to this attack through a languagebased Erlang application, which uses the processing power of a low-cost device. Its use would open the possibility of effective attacks coming from devices with less processing power, or from IoT devices, but capable of at least degrading the experience of a legitimate user, anonymously.