Untitled

Funder

Organizational Unit

Publications

Evaluation Metrics for Collaborative Fault Detection and Diagnosis in Cyber-Physical Systems

Publication . Piardi, Luis; Oliveira, Andre Schneider; Costa, Pedro; Leitão, Paulo

Cyber-physical systems (CPS) rapidly expand within industrial contexts in a new era of digitalization, processing power, and inter-device communication capabilities. These advancements integrate technologies such as the Internet of Things (IoT), artificial intelligence (AI), and cloud and edge computing, granting processes and operations a high degree of autonomy. In addition, these interconnections foster collective intelligence arising from information exchange and collaboration between components, often outperforming individual capabilities. This collective intelligence manifests in fault detection and diagnosis (FDD) tasks within CPS, as it significantly improves the flexibility, performance, and scalability. However, the inherent complexity of CPS poses challenges in determining the best configuration of the collaboration parameters, such as when and how to collaborate, wherein incorrect adjustments may lead to decision errors and compromise the system’s performance. With this in mind, this paper proposes seven metrics to evaluate collaboration performance for fault detection and diagnosis in multi-agent systems (MAS)-based CPS, evaluating when the collaboration is beneficial or when the collaboration parameters need to be adjusted. The experiments focus on collaborative fault detection in temperature and humidity sensors within warehouse racks, where the proposed evaluation metrics point out the impact of collaboration on the detection task, as well as possible actions to be adopted to improve the agent’s performance.

2024Conference object

Open access

MAS-based distributed cyber-physical system in smart warehouse

Publication . Piardi, Luis; Costa, Pedro; Oliveira, Andre Schneider; Leitão, Paulo

This paper presents an approach for a multi-agent-based cyber-physical system dedicated to operating the warehouse plant with a distributed approach. The recent technological evolution has improved the quality and robustness of the services for current warehouses. However, systems that operate warehouses do not follow this evolution, presenting predominantly central monolithic or hierarchical approaches, resulting in fragility related to flexibility, scalability, and robustness in the face of disturbances. In the proposed approach, each warehouse physical component has a computational unit associated, i.e. a cyber agent, with communication, negotiation, and data analysis capabilities. Agents contain all the information, algorithms, and functions necessary to operate the physical component, and instead of receiving orders from higher-layer agents, they negotiate and collaborate to perform the tasks. The proposed system was tested in a laboratory testbed, composed of six racks and up to eight robots for transporting products. Extensive experiments show the feasibility of the approach.

2023Conference object

Open access

Role of digital technologies to enhance the human integration in industrial cyber–physical systems

Publication . Piardi, Luis; Leitao, Paulo; Queiroz, Jonas; Pontes, Joseane

In the digital transformation era, and particularly in Industry 5.0, humans play an active role in industrial cyber-physical systems (CPS) since they are the most flexible piece in such automated systems. However, their integration is not easy and constitutes a relevant challenge, presenting different requirements according to the activities they execute and the related integration levels, i.e., Human -in -the -Loop (HitL) and Humanin -the -Mesh (HitM). Besides the use of human -centric design approaches, the use of digital technologies, namely Internet of Things, Artificial Intelligence, virtual and augmented reality and collaborative robotics, can contribute to empower humans to perform their operations in a faster and more efficient manner. This paper discusses how emergent digital technologies can enhance a more symbiotic integration of humans in industrial CPS, contributing with the analysis of different aspects and concerns that must be considered to properly enable the HitL and HitM integration levels in CPS. Four experimental case studies are presented to demonstrate the feasibility of using digital technologies to enhance the human -CPS integration, covering HitL and HitM levels. Furthermore, some challenges related to the human -integration factors affected by the digital technologies in such environments are briefly discussed and pointed out as research directions.

2024Journal article

Open access

Collaborative fault tolerance for cyber–physical systems: The detection stage

Publication . Piardi, Luís; Oliveira, André Schneider; Costa, Pedro; Leitão, Paulo

In the era of Industry 4.0, fault tolerance is essential for maintaining the robustness and resilience of industrial systems facing unforeseen or undesirable disturbances. Current methodologies for fault tolerance stages namely, detection, diagnosis, and recovery, do not correspond with the accelerated technological evolution pace over the past two decades. Driven by the advent of digital technologies such as Internet of Things, cloud and edge computing, and artificial intelligence, associated with enhanced computational processing and communication capabilities, local or monolithic centralized fault tolerance methodologies are out of sync with contemporary and future systems. Consequently, these methodologies are limited in achieving the maximum benefits enabled by the integration of these technologies, such as accuracy and performance improvements. Accordingly, in this paper, a collaborative fault tolerance methodology for cyber–physical systems, named Collaborative Fault * (CF*), is proposed. The proposed methodology takes advantage of the inherent data analysis and communication capabilities of cyber–physical components. The proposed methodology is based on multi-agent system principles, where key components are self-fault tolerant, and adopts collaborative and distributed intelligence behavior when necessary to improve its fault tolerance capabilities. Experiments were conducted focusing on the fault detection stage for temperature and humidity sensors in warehouse racks. The experimental results confirmed the accuracy and performance improvements under CF* compared with the local methodology and competitiveness when compared with a centralized approach.

2025Journal article

Open access