Open Access
Content adaptation and depth perception in an affordable multi-view display
(MDPI, 2020) Ezcurdia Aguirre, Íñigo Fermín; Arregui Roldán, Adriana; Ardaiz Villanueva, Óscar; Ortiz, Amalia; Marzo Pérez, Asier; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Gobierno de Navarra / Nafarroako Gobernua, 0011-1365-2019-000086; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, PJUPNA1923
We present SliceView, a simple and inexpensive multi-view display made with multiple parallel translucent sheets that sit on top of a regular monitor; each sheet reflects different 2D images that are perceived cumulatively. A technical study is performed on the reflected and transmitted light for sheets of different thicknesses. A user study compares SliceView with a commercial light-field display (LookingGlass) regarding the perception of information at multiple depths. More importantly, we present automatic adaptations of existing content to SliceView: 2D layered graphics such as retro-games or painting tools, movies and subtitles, and regular 3D scenes with multiple clipping z-planes. We show that it is possible to create an inexpensive multi-view display and automatically adapt content for it; moreover, the depth perception on some tasks is superior to the one obtained in a commercial light-field display. We hope that this work stimulates more research and applications with multi-view displays.
Open Access
Mental workload of guiding devices: directional pulling forces, vibrotactile stimuli and audio cues
(ACM, 2024-06-19) Donkov Bogdanov, Stefan; Elizondo Martínez, Sonia; Ezcurdia Aguirre, Íñigo Fermín; Sarasate Azcona, Iosune; Marzo Pérez, Asier; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
Asymmetric vibrations are known to produce a pulling sensation when stimulating the human hand. This effect has been exploited as a means of guidance. We conducted a user study to compare asymmetric vibrations, simple vibration, and sound cues for guidance in terms of task completion time and mental workload. Mental workload was evaluated (N=22) using the dual-task paradigm with a Stroop test and arithmetic operations test as secondary tasks. Audio cues improved significantly the task completion time for baseline and stroop tasks compared to the other methods. No significant differences were found for the reaction time for the guiding task. The use of audio cues was evaluated as the less mentally demanding guiding method on the NASA-TLX questionnaire.
Open Access
Complex selective manipulations of thermomagnetic programmable matter
(Springer Nature, 2022) Irisarri Erviti, Josu; Ezcurdia Aguirre, Íñigo Fermín; Sandúa Fernández, Xabier; Galarreta Rodríguez, Itziar; Pérez de Landazábal Berganzo, José Ignacio; Marzo Pérez, Asier; Ciencias; Zientziak; Ingeniería; Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2; Institute of Smart Cities - ISC
Programmable matter can change its shape, stiffness or other physical properties upon command. Previous work has shown contactless optically controlled matter or magnetic actuation, but the former is limited in strength and the latter in spatial resolution. Here, we show an unprecedented level of control combining light patterns and magnetic fields. A mixture of thermoplastic and ferromagnetic powder is heated up at specific locations that become malleable and are attracted by magnetic fields. These heated areas solidify on cool down, and the process can be repeated. We show complex control of 3D slabs, 2D sheets, and 1D filaments with applications in tactile displays and object manipulation. Due to the low transition temperature and the possibility of using microwave heating, the compound can be manipulated in air, water, or inside biological tissue having the potential to revolutionize biomedical devices, robotics or display technologies.
Open Access
Mid-air contactless haptics to augment VR experiences
(Association for Computing Machinery, 2023) Ezcurdia Aguirre, Íñigo Fermín; Fernández Ortega, Unai Javier; Olaz Moratinos, Xabier; Marzo Pérez, Asier; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
We present four technologies to deliver contactless haptic stimuli for enriching Virtual Reality (VR) experiences. The technologies are electrostatic piloerection, focused light-induced heat, electric plasma, and ultrasound; the user does not require to wear or touch any device. We describe the working principle behind each technology and how these technologies can provide new exciting sensations in VR experiences. Additionally, we showcase a VR demo experience gathering all four remote haptic stimuli along a circuit for the users to experiment with these new sensations.
Open Access
LeviPrint: contactless fabrication using full acoustic trapping of elongated parts
(ACM, 2022) Ezcurdia Aguirre, Íñigo Fermín; Morales González, Rafael; Andrade, Marco A.B.; Marzo Pérez, Asier; Institute of Smart Cities - ISC
LeviPrint is a system for assembling objects in a contactless manner using acoustic levitation. We explore a set of optimum acoustic fields that enables full trapping in position and orientation of elongated objects such as sticks. We then evaluate the capabilities of different ultrasonic levitators to dynamically manipulate these elongated objects. The combination of novel optimization algorithms and levitators enable the manipulation of sticks, beads and droplets to fabricate complex objects. A system prototype composed of a robot arm and a levitator is tested for different fabrication processes. We highlight the reduction of cross-contamination and the capability of building on top of objects from different angles as well as inside closed spaces. We hope that this technique inspires novel fabrication techniques and that reaches fields such as microfabrication of electromechanical components or even in-vivo additive manufacturing.
Open Access
LeviPrint: contactless additive manufacturing using acoustic levitation with position and orientation control of elongated parts
(2021) Ezcurdia Aguirre, Íñigo Fermín; Morales González, Rafael; Marzo Pérez, Asier; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
LeviPrint assembles small objects in a contactless way using ultrasonic phased-arrays and optimization algorithms. We explore a set of methods that enables 6 Degrees-of-Freedom (DoF) control of elongated bodies. We then evaluate different ultrasonic arrangements to optimize the manipulation of these bodies. The combination of arrangements and optimization algorithms allow us to levitate, orientate and assemble complex objects. These techniques and arrangements can be leveraged for the microfabrication of electromechanical components and in-vivo additive manufacturing. We highlight the reduction of cross-contamination and the capability to manufacture inside closed containers from the outside.
Open Access
Contactless electrostatic piloerection for haptic sensations
(IEEE, 2023) Iriarte Cárdenas, Naroa; Ezcurdia Aguirre, Íñigo Fermín; Elizondo Martínez, Sonia; Irisarri Erviti, Josu; Hemmerling, Daria; Ortiz Nicolás, Amalia; Marzo Pérez, Asier; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
In this project, we create artificial piloerection using contactless electrostatics to induce tactile sensations in a contactless way. Firstly, we design various high-voltage generators and evaluate them in terms of their static charge, safety and frequency response with different electrodes as well as grounding strategies. Secondly, a psychophysics user study revealed which parts of the upper body are more sensitive to electrostatic piloerection and what adjectives are associated with them. Finally, we combine an electrostatic generator to produce artificial piloerection on the nape with a head-mounted display, this device provides an augmented virtual experience related to fear. We hope that work encourages designers to explore contactless piloerection for enhancing experiences such as music, short movies, video games, or exhibitions.
Open Access
Interactions with digital mountains: tangible, immersive and touch interactive virtual reality
(Association for Computing Machinery (ACM), 2020) Ardaiz Villanueva, Óscar; Marzo Pérez, Asier; Baztán Larrea, Rubén; Ezcurdia Aguirre, Íñigo Fermín; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Gobierno de Navarra / Nafarroako Gobernua, PI043-2019; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Digitization of Earth mountains and terrains has facilitated to plan journeys, manage natural resources, and learn about the Earth from the comfort of our homes. We aim to develop new interactions on digital mountains with novel interfaces: 3D printed representation of a mountain, an immersive virtual reality visualization, and two different touch interactive interfaces for immersive virtual reality visualizations: a 3D printed mountain with touch sensors and a multitouch tablet. We show how we have built such prototypes based on digital data retrieved from a map provider, and which interactions are possible with each interaction device. We explain how we design and conduct evaluation.
Open Access
Microfluidic platform using focused ultrasound passing through hydrophobic meshes with jump availability
(Oxford University Press, 2023) Koroyasu, Yusuke; Nguyen, Thanh-Vinh; Sasaguri, Shun; Marzo Pérez, Asier; Ezcurdia Aguirre, Íñigo Fermín; Nagata, Yuuya; Yamamoto, Tatsuya; Nomura, Nobuhiko; Hoshi, Takayuki; Ochiai, Yoichi; Fushimi, Tatsuki; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
Applications in chemistry, biology, medicine, and engineering require the large-scale manipulation of a wide range of chemicals, samples, and specimens. To achieve maximum efficiency, parallel control of microlitre droplets using automated techniques is essential. Electrowetting-on-dielectric (EWOD), which manipulates droplets using the imbalance of wetting on a substrate, is the most widely employed method. However, EWOD is limited in its capability to make droplets detach from the substrate (jumping), which hinders throughput and device integration. Here, we propose a novel microfluidic system based on focused ultrasound passing through a hydrophobic mesh with droplets resting on top. A phased array dynamically creates foci to manipulate droplets of up to 300 mu L. This platform offers a jump height of up to 10 cm, a 27-fold improvement over conventional EWOD systems. In addition, droplets can be merged or split by pushing them against a hydrophobic knife. We demonstrate Suzuki-Miyaura cross-coupling using our platform, showing its potential for a wide range of chemical experiments. Biofouling in our system was lower than in conventional EWOD, demonstrating its high suitability for biological experiments. Focused ultrasound allows the manipulation of both solid and liquid targets. Our platform provides a foundation for the advancement of micro-robotics, additive manufacturing, and laboratory automation.
Open Access
Electric plasma guided with ultrasonic fields
(American Association for the Advancement of Science, 2025-02-05) Irisarri Erviti, Josu; Ezcurdia Aguirre, Íñigo Fermín; Iriarte Cárdenas, Naroa; Sirkka, Marika; Nikolaev, Dmitry; Mäkinen, Joni; Martinez-Marchese, Alexander; Iablonskyi, Denys; Salmi, Ari; Marzo Pérez, Asier; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
Electric plasma forms sparks in midair that transfer electrical current. This current can power high-voltage electronics, kill bacteria, produce tactile sensations, or be used for welding. However, the formation of the spark is chaotic and hard to control. Laser pulses can guide discharges but require high power and are disruptive and cumbersome to control. Here, we show that ultrasonic fields can guide plasma sparks, even around obstacles. The ultrasonic beams can be directed dynamically and within milliseconds, enabling precise, nondangerous, and fast control of high-voltage sparks. This phenomenon can be used for applications in high-voltage switching and plasma treatments.