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Detalhes

Detalhes

  • Nome

    José Lima
  • Cargo

    Investigador Colaborador Externo
  • Desde

    01 junho 2009
010
Publicações

2025

Performance Comparison Between Position Controllers for a Robotic Arm Manipulator

Autores
Braun, J; Chellal, AA; Lima, J; Pinto, VH; Pereira, AI; Costa, P;

Publicação
2025 IEEE INTERNATIONAL CONFERENCE ON AUTONOMOUS ROBOT SYSTEMS AND COMPETITIONS, ICARSC

Abstract
This paper compares five PID controller architectures for robotic manipulator position control, addressing the challenge of maintaining performance under varying inertial loads while providing accessible implementations for research and education. The five PID controller architectures for a three degrees-of-freedom SCARA manipulator position control are a basic Proportional-Derivative (PD), PD with Feed-Forward (FF), Parallel PD-PI-FF, Cascade PD-PI-FF, and Cascade PD-PI-FF with dead zone (DZ) compensation. The controllers were evaluated under varying inertial loads to assess robustness, extending beyond previous work's idealized conditions. Results show advanced configurations reduced errors by up to 64% compared to the baseline PD, with Parallel-FF achieving optimal dynamic performance and Cascade-FF-DZ excelling in steady-state control. The Feed-Forward addition enhanced tracking performance, while DZ compensation effectively eliminated limit cycles. The work provides open-source implementations and simulation environments, supporting research reproducibility and educational applications in robotics control.

2025

A Machine Learning Approach for Enhanced Glucose Prediction in Biosensors

Autores
Abreu, A; Oliveira, DD; Vinagre, I; Cavouras, D; Alves, JA; Pereira, AI; Lima, J; Moreira, FTC;

Publicação
CHEMOSENSORS

Abstract
The detection of glucose is crucial for diagnosing diseases such as diabetes and enables timely medical intervention. In this study, a disposable enzymatic screen-printed electrode electrochemical biosensor enhanced with machine learning (ML) for quantifying glucose in serum is presented. The platinum working surface was modified by chemical adsorption with biographene (BGr) and glucose oxidase, and the enzyme was encapsulated in polydopamine (PDP) by electropolymerisation. Electrochemical characterisation and morphological analysis (scanning and transmission electron microscopy) confirmed the modifications. Calibration curves in Cormay serum (CS) and selectivity tests with chronoamperometry were used to evaluate the biosensor's performance. Non-linear ML regression algorithms for modelling glucose concentration and calibration parameters were tested to find the best-fit model for accurate predictions. The biosensor with BGr and enzyme encapsulation showed excellent performance with a linear range of 0.75-40 mM, a correlation of 0.988, and a detection limit of 0.078 mM. Of the algorithms tested, the decision tree accurately predicted calibration parameters and achieved a coefficient of determination above 0.9 for most metrics. Multilayer perceptron models effectively predicted glucose concentration with a coefficient of determination of 0.828, demonstrating the synergy of biosensor technology and ML for reliable glucose detection.

2025

An Over-Actuated Hexacopter Tilt-Rotor UAV Prototype for Agriculture of Precision: Modeling and Control

Autores
Pimentel, GO; dos Santos, MF; Lima, J; Mercorelli, P; Fernandes, FM;

Publicação
SENSORS

Abstract
This paper focuses on the modeling, control, and simulation of an over-actuated hexacopter tilt-rotor (HTR). This configuration implies that two of the six actuators are independently tilted using servomotors, which provide high maneuverability and reliability. This approach is predicted to maintain zero pitch throughout the trajectory and is expected to improve the aircraft's steering accuracy. This arrangement is particularly beneficial for precision agriculture (PA) applications where accurate monitoring and management of crops are critical. The enhanced maneuverability allows for precise navigation in complex vineyard environments, enabling the unmanned aerial vehicle (UAV) to perform tasks such as aerial imaging and crop health monitoring. The employed control architecture consists of cascaded proportional (P)-proportional, integral and derivative (PID) controllers using the successive loop closure (SLC) method on the five controlled degrees of freedom (DoFs). Simulated results using Gazebo demonstrate that the HTR achieves stability and maneuverability throughout the flight path, significantly improving precision agriculture practices. Furthermore, a comparison of the HTR with a traditional hexacopter validates the proposed approach.

2025

Nonlinear Control of Mecanum-Wheeled Robots Applying <i>H</i><sub>8</sub> Controller

Autores
Chellal, AA; Braun, J; Lima, J; Goncalves, J; Valente, A; Costa, P;

Publicação
2025 IEEE INTERNATIONAL CONFERENCE ON AUTONOMOUS ROBOT SYSTEMS AND COMPETITIONS, ICARSC

Abstract
Mecanum wheeled mobile robots have become relevant due to their excellent maneuverability, enabling omnidirectional motion in constrained environments as a requirement in industrial automation, logistics, and service robotics. This paper addresses a low-level controller based on the H-Infinity (H-infinity) control method for a four-wheel Mecanum mobile robot. The proposed controller ensures stability and performance despite model uncertainties and external disturbances. The dynamic model of the robot was developed and introduced in MATLAB to generate the controller. Further, the controller's performance is validated and compared to a traditional PID controller using the SimTwo simulator, a realistic physics-based simulator with dynamics of rigid bodies incorporating non-linearities such as motor dynamics and friction effects. The preliminary simulation results show that the H-infinity reached a time-independent Euclidean error of 0.0091 m, compared to 0.0154 m error for the PID in trajectory tracking. Demonstrating that the H-infinity controller handles nonlinear dynamics and disturbances, ensuring precise trajectory tracking and improved system performance. This research validates the proposed approach for advanced control of Mecanum wheeled robots.

2025

Systematic review of predictive maintenance practices in the manufacturing sector

Autores
Benhanifia, A; Ben Cheikh, Z; Oliveira, PM; Valente, A; Lima, J;

Publicação
INTELLIGENT SYSTEMS WITH APPLICATIONS

Abstract
Predictive maintenance (PDM) is emerging as a strong transformative tool within Industry 4.0, enabling significant improvements in the sustainability and efficiency of manufacturing processes. This in-depth literature review, which follows the PRISMA 2020 framework, examines how PDM is being implemented in several areas of the manufacturing industry, focusing on how it is taking advantage of technological advances such as artificial intelligence (AI) and the Internet of Things (IoT). The presented in-depth evaluation of the technological principles, implementation methods, economic consequences, and operational improvements based on academic and industrial sources and new innovations is performed. According to the studies, integrating CDM can significantly increase machine uptime and reliability while reducing maintenance costs. In addition, the transition to PDM systems that use real-time data to predict faults and plan maintenance more accurately holds out promising prospects. However, there are still gaps in the overall methodologies for measuring the return on investment of PDM implementations, suggesting an essential research direction.