arXiv subjects

Fernando Moreu

Publications and source records attributed to Fernando Moreu.

12 recordsLinked to original sources

arXiv2026

Low-cost IoT-Based Rainfall Monitoring with Web-Based Data Access

Rainfall measurement with high spatial and temporal resolution is critical for flood forecasting, drought mitigation, and disaster preparedness. Rainfall patterns are highly variable, both geographically and over time. This variability presents a significant challenge for monitoring, as rain gauges can accurately capture temporal patterns only at a single location. Furthermore, the high cost of commercial instruments restricts their widespread deployment, and rain gauge networks often fail to adequately capture the spatial heterogeneity of precipitation patterns. To address these limitations, this study introduces a low-cost IoT-based rainfall monitoring system developed upon the Low-cost Efficient Wireless Intelligent Sensor (LEWIS) platform. Four rainfall sensors were designed, developed, and deployed at different locations across the semi-arid region of the United States, in the State of New Mexico, to capture localized precipitation variability. Each sensor node integrates a rainfall detection module with an LTE-enabled microcontroller and is powered by a compact solar-battery system, ensuring autonomous and self-sufficient operation. Real-time precipitation data are transmitted to a cloud server for continuous access, visualization, and integration with early-warning frameworks. The results demonstrate that IoT-based rainfall monitoring can achieve reliable accuracy at a fraction of the cost of conventional gauges, while supporting dense deployment for microscale precipitation analysis. Comparative validation with model-based precipitation data and in situ observations shows strong agreement in the detection and timing of recorded precipitation events, highlighting the system potential for early warning, disaster risk reduction, and bias correction of remotely sensed precipitation products by filling observational gaps in under-instrumented semi-arid areas.

eess.SP↗

arXiv2026

Integrating acoustic tapping with a UAV platform for tile condition classification

Ensuring the structural integrity of building tiles is important for public safety and the durability of urban infrastructure. This study proposes a controlled experimental framework to quantify the effect of Unmanned Aerial vehicle (UAV) induced dynamic perturbations on acoustic tap-testing reliability for facade inspection. This work explicitly analyzes vibration-induced degradation and introduces an energy-based signal correction method to preserve classification performance under motion disturbances. In addition, Principal Component Analysis (PCA) is applied to process and classify wirelessly acquired acoustic data, reducing dimensionality while preserving key defect related features. A Stewart platform is used to reproduce controlled oscillatory conditions derived from UAV flight characterization, enabling systematic evaluation across multiple vibration amplitudes. Results show that classification accuracy degrades significantly under increasing perturbations, but can be restored above 98% using the proposed energy-based filtering approach.

eess.SP↗

arXiv2026

Human-Augmented Reality Interaction in Rebar Inspection

Rebar inspection in reinforced concrete construction requires sustained awkward postures and complex mental mapping of two-dimensional drawings onto three-dimensional assemblies. This study evaluated an Augmented Reality (AR)-assisted rebar inspection system deployed on Microsoft HoloLens 2 through a within-subjects experiment with 30 participants. Full-body kinematics were recorded using a motion capture system at 100 Hz while participants performed traditional and AR-assisted spacing inspection. AR reduced mean trunk flexion by 30.8%, mean neck flexion by 32.8%, and task completion time by 67.7%. Walking distance and hand-path length each decreased by over 50%. NASA Task Load Index scores decreased by 45.6% overall, with the largest reduction in physical demand. Inspection accuracy was maintained across conditions. The System Usability Scale yielded a mean score of 76.1 with 83% of participants rating the system acceptable. These results provide convergent objective and subjective evidence that AR-assisted inspection reduces ergonomic risk and perceived workload maintaining inspection quality.

cs.HC↗

arXiv2024

Methodology to Deploy CNN-Based Computer Vision Models on Immersive Wearable Devices

Convolutional Neural Network (CNN) models often lack the ability to incorporate human input, which can be addressed by Augmented Reality (AR) headsets. However, current AR headsets face limitations in processing power, which has prevented researchers from performing real-time, complex image recognition tasks using CNNs in AR headsets. This paper presents a method to deploy CNN models on AR headsets by training them on computers and transferring the optimized weight matrices to the headset. The approach transforms the image data and CNN layers into a one-dimensional format suitable for the AR platform. We demonstrate this method by training the LeNet-5 CNN model on the MNIST dataset using PyTorch and deploying it on a HoloLens AR headset. The results show that the model maintains an accuracy of approximately 98%, similar to its performance on a computer. This integration of CNN and AR enables real-time image processing on AR headsets, allowing for the incorporation of human input into AI models.

cs.CV↗

arXiv2024

Immersive Robot Programming Interface for Human-Guided Automation and Randomized Path Planning

Researchers are exploring Augmented Reality (AR) interfaces for online robot programming to streamline automation and user interaction in variable manufacturing environments. This study introduces an AR interface for online programming and data visualization that integrates the human in the randomized robot path planning, reducing the inherent randomness of the methods with human intervention. The interface uses holographic items which correspond to physical elements to interact with a redundant manipulator. Utilizing Rapidly Random Tree Star (RRT*) and Spherical Linear Interpolation (SLERP) algorithms, the interface achieves end-effector s progression through collision-free path with smooth rotation. Next, Sequential Quadratic Programming (SQP) achieve robot s configurations for this progression. The platform executes the RRT* algorithm in a loop, with each iteration independently exploring the shortest path through random sampling, leading to variations in the optimized paths produced. These paths are then demonstrated to AR users, who select the most appropriate path based on the environmental context and their intuition. The accuracy and effectiveness of the interface are validated through its implementation and testing with a seven Degree-OF-Freedom (DOF) manipulator, indicating its potential to advance current practices in robot programming. The validation of this paper include two implementations demonstrating the value of human-in-the-loop and context awareness in robotics.

cs.RO↗

arXiv2023

Feedback and Control of Dynamics and Robotics using Augmented Reality

Human-machine interaction (HMI) and human-robot interaction (HRI) can assist structural monitoring and structural dynamics testing in the laboratory and field. In vibratory experimentation, one mode of generating vibration is to use electrodynamic exciters. Manual control is a common way of setting the input of the exciter by the operator. To measure the structural responses to these generated vibrations sensors are attached to the structure. These sensors can be deployed by repeatable robots with high endurance, which require on-the-fly control. If the interface between operators and the controls was augmented, then operators can visualize the experiments, exciter levels, and define robot input with a better awareness of the area of interest. Robots can provide better aid to humans if intelligent on-the-fly control of the robot is: (1) quantified and presented to the human; (2) conducted in real-time for human feedback informed by data. Information provided by the new interface would be used to change the control input based on their understanding of real-time parameters. This research proposes using Augmented Reality (AR) applications to provide humans with sensor feedback and control of actuators and robots. This method improves cognition by allowing the operator to maintain awareness of structures while adjusting conditions accordingly with the assistance of the new real-time interface. One interface application is developed to plot sensor data in addition to voltage, frequency, and duration controls for vibration generation. Two more applications are developed under similar framework, one to control the position of a mediating robot and one to control the frequency of the robot movement. This paper presents the proposed model for the new control loop and then compares the new approach with a traditional method by measuring time delay in control input and user efficiency.

cs.RO↗

arXiv2023

Low-cost Efficient Wireless Intelligent Sensor (LEWIS) for Engineering, Research, and Education

Sensors have the capability of collecting engineering data and quantifying environmental changes, activities, or phenomena. Civil engineers lack of knowledge in sensor technology. Therefore, the vision of smart cities equipped with sensors informing decisions has not been realized to date. The cost associated with data acquisition systems, laboratories, and experiments restricts access to sensors for wider audiences. Recently, sensors are becoming a new tool in education and training, giving learners real-time information that can reinforce their confidence and understanding of scientific or engineering new concepts. However, the electrical components and computer knowledge associated with sensors are still a challenge for civil engineers. If sensing technology costs and use are simplified, sensors could be tamed by civil engineering students. The researcher developed, fabricated, and tested an efficient low-cost wireless intelligent sensor (LEWIS) aimed at education and research, named LEWIS1. This platform is directed at learners connected with a cable to the computer but has the same concepts and capabilities as the wireless version. The content of this paper describes the hardware and software architecture of the first prototype and their use, as well as the proposed new LEWIS1 (LEWIS1 beta) that simplifies both hardware and software, and user interfaces. The capability of the proposed sensor is compared with an accurate commercial PCB sensor through experiments. The later part of this paper demonstrates applications and examples of outreach efforts and suggests the adoption of LEWIS1 beta as a new tool for education and research. The authors also investigated the number of activities and sensor building workshops that has been done since 2015 using the LEWIS sensor which shows an ascending trend of different professionals excitement to involve and learn the sensor fabrication.

cs.CY↗

arXiv2021

Implementing augmented reality technology to measure structural changes across time

In recent years, augmented reality (AR) technology has been increasingly employed in structural health monitoring (SHM). In the case of conditions following a seismic event, inspections are conducted to evaluate the progression of the damage pattern quantitatively and efficiently respond if the displacement pattern is determined to be unsafe. Additionally, quantification of nearby structural changes over short-term and long-term periods can provide building inspectors with information to improve safety. This paper proposes the Time Machine Measure (TMM) application on an Augmented Reality (AR) Head-Mounted-Device (HMD) platform. The main function of the TMM application is to restore the saved meshes of a past environment and overlay them onto the real environment so that inspectors can intuitively measure structural deformation and other movement across time. The proposed TMM application was verified by experiments meant to simulate a real-world inspection.

cs.HC↗

arXiv2021

State of the Art of Augmented Reality (AR) Capabilities for Civil Infrastructure Applications

Augmented Reality (AR) is a technology superimposing interactional virtual objects onto a real environment. Since the beginning of the millennium, AR technologies have shown rapid growth, with significant research publications in engineering and science. However, the civil infrastructure community has minimally implemented AR technologies to date. One of the challenges that civil engineers face when understanding and using AR is the lack of a classification of AR in the context of capabilities for civil infrastructure applications. Practitioners in civil infrastructure, like most engineering fields, prioritize understanding the level of maturity of a new technology before considering its adoption and field implementation. This paper compares the capabilities of sixteen AR Head-Mounted Devices (HMDs) available in the market since 2017, ranking them in terms of performance for civil infrastructure implementations. Finally, the authors recommend a development framework for practical AR interfaces with civil infrastructure and operations.

cs.HC↗

arXiv2021

Measuring Total Transverse Reference-free Displacements of Railroad Bridges using 2 Degrees of Freedom (2DOF): Experimental Validation

Railroad bridge engineers are interested in the displacement of railroad bridges when the train is crossing the bridge for engineering decision making of their assets. Measuring displacements under train crossing events is difficult. If simplified reference-free methods would be accurate and validated, owners would conduct objective performance assessment of their bridge inventories under trains. Researchers have developed new sensing technologies (reference-free) to overcome the limitations of reference point-based displacement sensors. Reference-free methods use accelerometers to estimate displacements, by decomposing the total displacement in two parts: a high-frequency dynamic displacement component, and a low-frequency pseudo-static displacement component. In the past, researchers have used the Euler-Bernoulli beam theory formula to estimate the pseudo-static displacement assuming railroad bridge piles and columns can be simplified as cantilever beams. However, according to railroad bridge managers, railroad bridges have a different degree of fixity for each pile of each bent. Displacements can be estimated assuming a similar degree of fixity for deep foundations, but inherent errors will affect the accuracy of displacement estimation. This paper solves this problem expanding the 1 Degree of Freedom (1DOF) solution to a new 2 Degrees of Freedom (2DOF), to collect displacements under trains and enable cost-effective condition-based information related to bridge safety. Researchers developed a simplified beam to demonstrate the total displacement estimation using 2DOF and further conducted experimental results in the laboratory. The estimated displacement of the 2DOF model is more accurate than that of the 1DOF model for ten train crossing events. With only one sensor added to the ground of the pile, this method provides owners with approximately 40% more accurate displacements.

eess.SP↗

arXiv2021

Crack detection using tap-testing and machine learning techniques to prevent potential rockfall incidents

Rockfalls are a hazard for the safety of infrastructure as well as people. Identifying loose rocks by inspection of slopes adjacent to roadways and other infrastructure and removing them in advance can be an effective way to prevent unexpected rockfall incidents. This paper proposes a system towards an automated inspection for potential rockfalls. A robot is used to repeatedly strike or tap on the rock surface. The sound from the tapping is collected by the robot and subsequently classified with the intent of identifying rocks that are broken and prone to fall. Principal Component Analysis (PCA) of the collected acoustic data is used to recognize patterns associated with rocks of various conditions, including intact as well as rock with different types and locations of cracks. The PCA classification was first demonstrated simulating sounds of different characteristics that were automatically trained and tested. Secondly, a laboratory test was conducted tapping rock specimens with three different levels of discontinuity in depth and shape. A real microphone mounted on the robot recorded the sound and the data were classified in three clusters within 2D space. A model was created using the training data to classify the reminder of the data (the test data). The performance of the method is evaluated with a confusion matrix.

cs.LG↗

arXiv2021

Reducing Gaze Distraction for Real-time Vibration Monitoring Using Augmented Reality

Operators want to maintain awareness of the structure being tested while observing sensor data. Normally the human's gaze shifts to a separate device or screen during the experiment for data information, missing the structure's physical response. The human-computer interaction provides valuable data and information but separates the human from the reality. The sensor data does not collect experiment safety, quality, and other contextual information of critical value to the operator. To solve this problem, this research provides humans with real-time information about vibrations using an Augmented Reality (AR) application. An application is developed to augment sensor data on top of the area of interest, which allows the user to perceive real-time changes that the data may not warn of. This paper presents the results of an experiment that show how AR can provide a channel for direct sensor feedback while increasing awareness of reality. In the experiment a researcher attempts to closely follow a moving sensor with their own sensor while observing the moving sensor's data with and without AR. The results of the reported experiment indicate that augmenting the information collected from sensors in real-time narrows the operator's focus to the structure of interest for more efficient and informed experimentation.

cs.HC↗