Open Access
Automatic trajectory determination in automated robotic welding considering weld joint symmetry
(MDPI, 2023) Curiel Braco, David; Veiga Suárez, Fernando; Suárez, Alfredo; Villanueva Roldán, Pedro; Aldalur, Eider; Ingeniería; Ingeniaritza
The field of inspection for welded structures is currently in a state of rapid transformation driven by a convergence of global technological, regulatory, and economic factors. This evolution is propelled by several key drivers, including the introduction of novel materials and welding processes, continuous advancements in inspection technologies, innovative approaches to weld acceptance code philosophy and certification procedures, growing demands for cost-effectiveness and production quality, and the imperative to extend the lifespan of aging structures. Foremost among the challenges faced by producers today is the imperative to meet customer demands, which entails addressing both their explicit and implicit needs. Furthermore, the integration of emerging materials and technologies necessitates the exploration of fresh solutions. These solutions aim to enhance inspection process efficiency while providing precise quantitative insights into defect identification and location. To this end, our project proposes cutting-edge technologies, some of which have yet to gain approval within the sector. Noteworthy among these innovations is the integration of vision systems into welding robots, among other solutions. This paper introduces a groundbreaking algorithm for tool path selection, leveraging profile scanning and the concept of joint symmetry. The application of symmetry principles for trajectory determination represents a pioneering approach within this expansive field.
Open Access
Advancements and methodologies in directed energy deposition (DED-Arc) manufacturing: design strategies, material hybridization, process optimization and artificial intelligence
(IntechOpen, 2024-09-27) Uralde Jiménez, Virginia; Suárez, Alfredo; Veiga Suárez, Fernando; Villanueva Roldán, Pedro; Ballesteros Egüés, Tomás; Ingeniería; Ingeniaritza; Institute of Smart Cities - ISC
This chapter explores the latest advancements and methodologies in directed energy deposition (DED-arc) manufacturing. The introduction sets the stage for understanding the significance of these developments in the context of modern manufacturing needs. The discussion includes design strategies for DED-arc, emphasizing topological optimization, functional design, and generative design, alongside the application of artificial intelligence (AI) in enhancing design processes. Innovative approaches to material hybridization are detailed, focusing on both multilayer and in situ techniques for combining different materials to optimize component performance. The paper also covers slicing and pathing, examining slicing strategies, the use of lattice structures, and the implementation of 2D and 3D patterns to improve manufacturing efficiency and product quality. The conclusion summarizes key findings, discusses their implications for the additive manufacturing industry, and suggests potential future research directions in DED-arc technology, highlighting the emerging trends and innovations that are shaping the field.
Open Access
The integration of mechanical energy absorbers into rollover protective structures to improve the safety of agricultural tractors in the event of rollover
(MDPI, 2024) Alfaro López, José Ramón; Pérez Ezcurdia, Amaya; Latorre Biel, Juan Ignacio; Arana Navarro, Ignacio; Benito Amurrio, Marta; Villanueva Roldán, Pedro; Ingeniería; Ingeniaritza; Institute of Smart Cities - ISC; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, PJUPNA1912
The combination of safety belts and rollover protective structures (ROPSs) is key in improving the safety of agricultural tractors in the event of rollover. However, we also have the opportunity to enhance the security provided by each ROPS; one such example is the combination of this safety device with adequate mechanical energy absorbers (MEAs). Inexpensive disc-shaped MEAs can be included in the anchoring points of a ROPS onto the chassis of a tractor. Three configurations of ROPS combined with MEAs were tested during the application of loads that simulated the effects of side rollover in the vehicle. The tested configurations included a blank MEA as a reference case alongside a single MEA and a stack assembly containing both elements. The results of the tests show that both the deformation of the ROPS itself and the strain energy are larger in the case of blank MEAs; thus, there is also a risk that the clearance zone will be infringed upon and that the protective structure will collapse. We can conclude that the implementation of an appropriate MEA in ROPS reduces the deformation of the ROPS itself and its strain energy in cases of vehicle rollover; hence, the safety provided by such protection systems may be improved at a low cost.
Open Access
Recovered foam impact absorption systems
(MDPI, 2024-10-19) Marcelino Sádaba, Sara; Benito Hernández, Pablo; Martín Antunes, Miguel Ángel; Villanueva Roldán, Pedro; Veiga Suárez, Fernando; Ingeniería; Ingeniaritza
The use of foam materials in environments where they come into contact with individuals often results in deterioration, necessitating periodic replacements to maintain safety and hygiene standards. Foam, a lightweight, porous plastic formed by aggregated bubbles, possesses excellent impact-absorbing properties; however, its inherent porosity and susceptibility to wear present challenges. This project aims to develop a technological application for repurposing spent polyurethane (PU) foam from leisure facilities into effective impact absorption systems. By focusing on the reuse of deteriorated foam materials, this initiative seeks to minimize environmental impact while leveraging their beneficial technical characteristics. Addressing issues related to foam degradation, this project endeavors to create sustainable solutions by reintegrating spent foam into new systems. This innovative approach promotes sustainability while enhancing safety through the provision of high-quality, impact-resistant elements. Ultimately, this work aims to contribute to environmental conservation and the advancement of effective impact protection measures in leisure facilities.
Open Access
Evaluation of the potential of natural mining by-products as constituents of stabilized rammed earth building materials
(MDPI, 2025-05-06) Martín Antunes, Miguel Ángel; Perlot, Céline; Villanueva Roldán, Pedro; Abdallah, Rafik; Seco Meneses, Andrés; Ingeniería; Ingeniaritza; Institute of Smart Cities - ISC; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
In this investigation, different natural by-products were used to modify the Particle Size Distribution (PSD) of a soil to evaluate their potential in Stabilized Rammed Earth (SRE) building. Three different mixes were manufactured: (i) a mix composed entirely of a clayey soil, (ii) a mix consisting of mining by-products and clayey soil and (iii) a mix entirely based on mining by-products. Unstabilized and stabilized samples of the mixes were manufactured using two cement dosages (2.5% and 5%), and the samples were tested for Unconfined Compressive Strength (UCS), soaked UCS, and wetting and drying tests. Mining by-products demonstrated significant potential in SRE building, as their addition to the clayey soil resulted in higher UCS values compared to the UCS obtained from clayey soil alone. Unstabilized samples lost their integrity during exposure to water. The inclusion of mining by-products also showed potential as, although the mixes did not fully meet the requirements for soaked UCS and the wetting and drying tests, the mix containing both mining by-products and clayey soil retained its integrity in water, unlike the samples composed solely of clayey soil. M3C5 successfully met the requirements for soaked UCS and the wetting and drying tests, further highlighting the great potential of mining by-products in SRE building.
Open Access
Monitoring of blind rivets installations: contributions from the manufacturing chain and time-series imaging
(Elsevier, 2025-10-01) Penalva Oscoz, Mariluz; Gil del Val, Alain; Martín, Ander; Villanueva Roldán, Pedro; Uralde Jiménez, Virginia; Veiga Suárez, Fernando; Ingeniería; Ingeniaritza; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Fastening is a crucial operation in the aircraft manufacturing cycle, and the demand for automated solutions has grown in recent years. Blind rivets are particularly suitable for automation due to their ease of use. However, fastening with blind rivets requires indirect evaluation of the formed head for in-line quality monitoring. This study presents two approaches to address this problem. Firstly, an analysis of the drilling-riveting chain assesses the impact of the previous operation on riveting outcomes. Secondly, time-dependent signals from the riveting process are coded into images and analysed using deep learning techniques. Despite some limitations, both methods for monitoring blind riveting have demonstrated high precision and accuracy values above 0.9, with 1 indicating perfect precision or accuracy, suggesting that they can reliably predict the quality of rivet installations.
Open Access
Benefits of aeronautical preform manufacturing through arc-directed energy deposition manufacturing
(MDPI, 2023) Suárez, Alfredo; Ramiro, Pedro; Veiga Suárez, Fernando; Ballesteros Egüés, Tomás; Villanueva Roldán, Pedro; Ingeniería; Ingeniaritza
The paper introduces an innovative aerospace component production approach employing Wire Arc Additive Manufacturing (WAAM) technology to fabricate near-finished preforms from Ti6Al4V titanium. Tensile tests on WAAM Ti6Al4V workpieces demonstrated reliable mechanical properties, albeit with identified anisotropic behavior in horizontal samples, underscoring the need for optimization. This alternative manufacturing strategy addresses the challenges associated with machining forged preforms, marked by a high Buy To Fly (BTF) ratio (>10), leading to material wastage, prolonged machining durations, elevated tool expenses, and heightened waste and energy consumption. Additionally, logistical and storage costs are increased due to extended delivery timelines, exacerbated by supply issues related to the current unstable situation. The utilization of WAAM significantly mitigates initial BTF, preform costs, waste production, machining durations, and associated expenditures, while notably reducing lead times from months to mere hours. The novelty in this study lies in the application of Wire Arc Additive Manufacturing (WAAM) technology for the fabrication of titanium aircraft components. This approach includes a unique height compensation strategy and the implementation of various deposition strategies, such as single-seam, overlapping, and oscillating.
Open Access
Morphological design of a bicycle propulsion component using the hierarchical analysis process (AHP)
(MDPI, 2023) Villanueva Roldán, Pedro; Bona, Sergio; Lostado Lorza, Rubén; Veiga Suárez, Fernando; Ingeniería; Ingeniaritza
There are many mechanical and/or electrical energy storage devices nowadays which can be mounted on standard bicycles. The current trend regarding bicycle energy storage devices is to develop and improve electrical and electronic systems that can ease transportation. However, this paper shows the design process of a purely mechanical energy storage device, with no electrical components, which instead aims to entertain the user, producing a stimulus related to speed and physical exertion. The mechanical device has been designed according to an aspect or fashion known as steampunk, so that the mechanical elements forming the device (springs and spur gears) are visible to the user. The storage and discharge of energy are only produced by the user. In order to charge the device, after reaching an appropriate speed, the user uses the pedals in reverse motion. Alternatively, the mechanism can also be charged with a controlled braking system by actuating on a crank. The design process was based on the total design of Pugh and the AHP and QFD techniques.
Open Access
Weld joint reconstruction and classification algorithm for trajectory generation in robotic welding
(Trans Tech Publications, 2023) Curiel Braco, David; Veiga Suárez, Fernando; Suárez, Alfredo; Villanueva Roldán, Pedro; Aldalur, Eider; Ingeniería; Ingeniaritza
Open Access
Methodology for the path definition in multi-layer gas metal arc welding (GMAW)
(MDPI, 2023) Curiel Braco, David; Veiga Suárez, Fernando; Suárez, Alfredo; Villanueva Roldán, Pedro; Ingeniería; Ingeniaritza
The reconstruction of the geometry of weld-deposited materials plays an important role in the control of the torch path in GMAW. This technique, which is classified as a direct energy deposition technology, is experiencing a new emergence due to its use in welding and additive manufacturing. Usually, the torch path is determined by computerised fabrication tools, but these software tools do not consider the geometrical changes along the case during the process. The aim of this work is to adaptively define the trajectories between layers by analysing the geometry and symmetry of previously deposited layers. The novelty of this work is the integration of a profiling laser coupled to the production system, which scans the deposited layers. Once the layer is scanned, the geometry of the deposited bead can be reconstructed and the symmetry in the geometry and a continuous trajectory can be determined. A wall was fabricated under demanding deposition conditions, and a surface quality of around 100 microns and mechanical properties in line with those previously reported in the literature are observed.