Person:
Marzo Pérez, Asier

person.page.identifierURI

https://academica-e.unavarra.es/handle/2454/49548

Last Name

Marzo Pérez

First Name

Asier

person.page.departamento

Estadística, Informática y Matemáticas

person.page.instituteName

ISC. Institute of Smart Cities

ORCID

0000-0001-6433-1528

person.page.upna

8600

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Now showing 1 - 10 of 42

Open Access
Acoustic lock: position and orientation trapping of non-spherical sub-wavelength particles in mid-air using a single-axis acoustic levitator
(American Institute of Physics, 2018) Cox, L; Croxford, A; Drinkwater, Bruce W.; Marzo Pérez, Asier; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
We demonstrate acoustic trapping in both position and orientation of a non-spherical particle of sub-wavelength size in mid-air. To do so, we multiplex in time a pseudo-one-dimensional vertical standing wave and a twin-trap; the vertical standing wave provides converging forces that trap in position, whereas the twin-trap applies a stabilising torque that locks the orientation. The device operates at 40 kHz, and the employed multiplexing ratio of the 2 acoustic fields is 100:50 (standing:twin) periods. This ratio can be changed to provide tunability of the relative trapping strength and converging torque. The torsional spring stiffness of the trap is measured through simulations and experiments with good agreement. Cubes from k/5.56 (1.5 mm) to k/2.5 (3.4 mm) side length were stably locked. We also apply this technique to lock different non-spherical particles in midair: cubes, pyramids, cylinders, and insects such as flies and crickets. This technique adds significant functionality to mid-air acoustic levitation and will enable applications in micro-scale manufacturing as well as containment of specimens for examination and 3D-scanning.
Open Access
Comparison of experiment and simulation of ultrasonic mid-air haptic forces
(IEEE, 2022) Morales González, Rafael; Georgiou, Orestis; Marzo Pérez, Asier; Frier, William; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute of Smart Cities - ISC
Ultrasound mid-air haptics is an emerging technology with many applications in human-computer interactions. Despite great advances in related hardware and software, physics models that predict the resulting forces on a surface (e.g., someone's hand) are either too simple (inaccurate) or too complex (computationally expensive). In this paper, we show that simple models are not sufficient when predicting the force on an experimental setup involving two prototype devices and a precision scale. Specifically, we demonstrate that our experimental measurements cannot be accurately predicted using a linear acoustic model.
Open Access
Acoustophoretic volumetric displays using a fast-moving levitated particle
(AIP Publishing, 2019) Fushimi, Tatsuki; Marzo Pérez, Asier; Drinkwater, Bruce W.; Hill, Thomas L.; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
Displays have revolutionized the way we work and learn, and thus, the development of display technologies is of paramount importance. The possibility of a free-space display in which 3D graphics can be viewed from 360° without obstructions is an active area of research - holograms or lightfield displays can realize such a display, but they suffer from clipping and a limited field of view. Here, we use a phased array of ultrasonic emitters to realize a volumetric acoustophoretic display in which a millimetric particle is held in midair using acoustic radiation forces and moved rapidly along a 3D path. Synchronously, a light source illuminates the particle with the target color at each 3D position. We show that it is possible to render simple figures in real time (10 frames per second) as well as raster images at a lower frame rate. Additionally, we explore the dynamics of a fast-moving particle inside a phased-array levitator and identify potential sources of degradation in image quality. The dynamics are nonlinear and lead to distortion in the displayed images, and this distortion increases with drawing speed. The created acoustophoretic display shows promise as a future form of display technology.
Open Access
Holographic acoustic tweezers
(National Academy of Sciences, 2019) Marzo Pérez, Asier; Drinkwater, Bruce W.; Ingeniería; Ingeniaritza
Acoustic tweezers use sound radiation forces to manipulate matter without contact. They provide unique characteristics compared with the more established optical tweezers, such as higher trapping forces per unit input power and the ability to manipulate objects from the micrometer to the centimeter scale. They also enable the trapping of a wide range of sample materials in various media. A dramatic advancement in optical tweezers was the development of holographic optical tweezers (HOT) which enabled the independent manipulation of multiple particles leading to applications such as the assembly of 3D microstructures and the probing of soft matter. Now, 20 years after the development of HOT, we present the realization of holographic acoustic tweezers (HAT). We experimentally demonstrate a 40-kHz airborne HAT system implemented using two 256-emitter phased arrays and manipulate individually up to 25 millimetric particles simultaneously. We show that the maximum trapping forces are achieved once the emitting array satisfies Nyquist sampling and an emission phase discretization below π/8 radians. When considered on the scale of a wavelength, HAT provides similar manipulation capabilities as HOT while retaining its unique characteristics. The examples shown here suggest the future use of HAT for novel forms of displays in which the objects are made of physical levitating voxels, assembly processes in the micrometer and millimetric scale, as well as positioning and orientation of multiple objects which could lead to biomedical applications.
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
Standing waves for acoustic levitation
(Springer, 2020) Marzo Pérez, Asier; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
Standing waves are the most popular method to achieve acoustic trapping. Particles with greater acoustic impedance than the propagation medium will be trapped at the pressure nodes of a standing wave. Acoustic trapping can be used to hold particles of various materials and sizes, without the need of a close-loop controlling system. Acoustic levitation is a helpful and versatile tool for biomaterials and chemistry, with applications in spectroscopy and lab-on-a-droplet procedures. In this chapter, multiple methods are presented to simulate the acoustic field generated by one or multiple emitters. From the acoustic field, models such as the Gor'kov potential or the Flux Integral are applied to calculate the force exerted on the levitated particles. The position and angle of the acoustic emitters play a fundamental role, thus we analyse commonly used configurations such as emitter and reflector, two opposed emitters, or arrangements using phased arrays.
Open Access
Automatic contactless injection, transportation, merging, and ejection of droplets with a multifocal point acoustic levitator
(AIP Publishing, 2018) Brizzotti Andrade, Marco Aurélio; Camargo, Thales S. A.; Marzo Pérez, Asier; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
We present an acoustic levitation system that automatically injects, transports, merges and ejects liquid droplets in mid-air. The system consists of a phased array operating at 40 kHz on top of a plane reflector. The phase array generates multiple focal points at independent positions that form standing waves between the array and the reflector. In the reflector there is an inlet for a piezoelectric droplet injector which automatically inserts liquid droplets at the lower pressure nodes of the standing waves, and a hole that serves as an outlet for ejecting the processed droplets out of the system. Simulations of the acoustic radiation potential acting on the levitating droplets are in good agreement with the experiments. High-speed footage captured the functioning of the system in four fluidic operations: injection, transport, merging and ejection of liquid droplets. Having these operations integrated reliably into a single automatic system paves the way for the adoption of mid-air acoustophoretic processing in biological, chemical and pharmaceutical applications.
Open Access
Full-space metasurface at millimeter-wave frequencies
(IEEE, 2023) Ruiz Fernández de Arcaya, María; Marzo Pérez, Asier; Beruete Díaz, Miguel; Institute of Smart Cities - ISC
Conventional metasurfaces provide control over the electromagnetic waves in a single working frequency operating either in transmission or reflection. Full-Space Metasurfaces (FSM) are an extension that allows operation at two different frequencies with independent functionalities in transmission and reflection. This paper presents a gradient index FSM device based on a 3-layered unit cell where the phase modulation is implemented following the Pancharatman-Berry (PB) principle. The device is designed to operate at millimeter waves, with the lowest frequency operating in reflection and the highest one in transmission. To check the structure performance, a metasurface was designed to provide beam steering in reflection at 49.4 GHz and an amplitude image hologram in transmission at 104 GHz.
Open Access
Comparing a mid-air two-hand pinching point-and-click technique with mouse, keyboard and touchfree
(Association for Computing Machinery, 2024-01-18) Lafuente Duque, Melchor; Elizondo Martínez, Sonia; Fernández Ortega, Unai Javier; Marzo Pérez, Asier; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika
Some of our daily activities are performed by interacting with public touchscreens, such as food kiosks, bank tellers and newsstands. Nonetheless, the physical contact with these screens that are used by different people may be considered unhygienic. To avoid contact, some screens already integrate one-hand contactless interaction technologies, i.e. Leap Motion Controller, though they may lead to arm fatigue and slow performance. We present LeapPointer, a mid-Air two-hand pinching point-And-click technique. Specifically, this technique relies on a Leap Motion device to track both hands, and proposes a new software tool that allows bimanual selection through pointing and pinching gestures. A user study was performed to compare LeapPointer with two other techniques: The common mouse/keyboard and the current UltraLeap's TouchFree technique. Task completion time and accuracy as well as subjective data were gathered. The analysis of these data suggested that LeapPointer is significantly faster than the other touchless technique although less accurate. Self-reported fatigue was less with LeapPointer than with TouchFree.
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.