arXiv subjects

Yoichi Ochiai

Publications and source records attributed to Yoichi Ochiai.

At least 37 records · Page 2Linked to original sources

arXiv2025

null2: Boundary-Dissolving Bodies and Architecture towards Digital Nature

This paper presents a case study of the thematic pavilion null2 at Expo 2025 Osaka-Kansai, contrasting with the static Jomon motifs of Taro Okamoto's Tower of the Sun from Expo 1970. The study discusses Yayoi-inspired mirror motifs and dynamically transforming interactive spatial configuration of null2, where visitors become integrated as experiential content. The shift from static representation to a new ontological and aesthetic model, characterized by the visitor's body merging in real-time with architectural space at installation scale, is analyzed. Referencing the philosophical context of Expo 1970 theme 'Progress and Harmony for Mankind,' this research reconsiders the worldview articulated by null2 in Expo 2025, in which computation is naturalized and ubiquitous, through its intersection with Eastern philosophical traditions. It investigates how immersive experiences within the pavilion, grounded in the philosophical framework of Digital Nature, reinterpret traditional spatial and structural motifs of the tea room, positioning them within contemporary digital art discourse. The aim is to contextualize and document null2 as an important contemporary case study from Expo practices, considering the historical and social background in Japan from the 19th to 21st century, during which world expositions served as pivotal points for the birth of modern Japanese concept of 'fine art,' symbolic milestones of economic development, and key moments in urban and media culture formation. Furthermore, this paper academically organizes architectural techniques, computer graphics methodologies, media art practices, and theoretical backgrounds utilized in null2, highlighting the scholarly significance of preserving these as an archival document for future generations.

cs.HC↗

arXiv2025

Dynamic Caustics by Ultrasonically Modulated Liquid Surface

This paper presents a method for generating dynamic caustic patterns by utilising dual-optimised holographic fields with Phased Array Transducer (PAT). Building on previous research in static caustic optimisation and ultrasonic manipulation, this approach employs computational techniques to dynamically shape fluid surfaces, thereby creating controllable and real-time caustic images. The system employs a Digital Twin framework, which enables iterative feedback and refinement, thereby improving the accuracy and quality of the caustic patterns produced. This paper extends the foundational work in caustic generation by integrating liquid surfaces as refractive media. This concept has previously been explored in simulations but not fully realised in practical applications. The utilisation of ultrasound to directly manipulate these surfaces enables the generation of dynamic caustics with a high degree of flexibility. The Digital Twin approach further enhances this process by allowing for precise adjustments and optimisation based on real-time feedback. Experimental results demonstrate the technique's capacity to generate continuous animations and complex caustic patterns at high frequencies. Although there are limitations in contrast and resolution compared to solid-surface methods, this approach offers advantages in terms of real-time adaptability and scalability. This technique has the potential to be applied in a number of areas, including interactive displays, artistic installations and educational tools. This research builds upon the work of previous researchers in the fields of caustics optimisation, ultrasonic manipulation, and computational displays. Future research will concentrate on enhancing the resolution and intricacy of the generated patterns.

cs.GR↗

arXiv2025

Insect-Computer Hybrid Speaker: Speaker using Chirp of the Cicada Controlled by Electrical Muscle Stimulation

We propose "Insect-Computer Hybrid Speaker", which enables us to make musics made from combinations of computer and insects. Lots of studies have proposed methods and interfaces for controlling insects and obtaining feedback. However, there have been less research on the use of insects for interaction with third parties. In this paper, we propose a method in which cicadas are used as speakers triggered by using Electrical Muscle Stimulation (EMS). We explored and investigated the suitable waveform of chirp to be controlled, the appropriate voltage range, and the maximum pitch at which cicadas can chirp.

cs.HC↗

arXiv2025

See-Through Face Display for DHH People: Enhancing Gaze Awareness in Remote Sign Language Conversations with Camera-Behind Displays

This paper presents a sign language conversation system based on the See-Through Face Display to address the challenge of maintaining eye contact in remote sign language interactions. A camera positioned behind a transparent display allows users to look at the face of their conversation partner while appearing to maintain direct eye contact. Unlike conventional methods that rely on software-based gaze correction or large-scale half-mirror setups, this design reduces visual distortions and simplifies installation. We implemented and evaluated a videoconferencing system that integrates See-Through Face Display, comparing it to traditional videoconferencing methods. We explore its potential applications for Deaf and Hard of Hearing (DHH), including multi-party sign language conversations, corpus collection, remote interpretation, and AI-driven sign language avatars. Collaboration with DHH communities will be key to refining the system for real-world use and ensuring its practical deployment.

cs.HC↗

arXiv2025

From Geometry to Culture: An Iterative VLM Layout Framework for Placing Objects in Complex 3D Scene Contexts

3D layout tasks have traditionally concentrated on geometric constraints, but many practical applications demand richer contextual understanding that spans social interactions, cultural traditions, and usage conventions. Existing methods often rely on rule-based heuristics or narrowly trained learning models, making them difficult to generalize and frequently prone to orientation errors that break realism. To address these challenges, we define four escalating context levels, ranging from straightforward physical placement to complex cultural requirements such as religious customs and advanced social norms. We then propose a Vision-Language Model-based pipeline that inserts minimal visual cues for orientation guidance and employs iterative feedback to pinpoint, diagnose, and correct unnatural placements in an automated fashion. Each adjustment is revisited through the system's verification process until it achieves a coherent result, thereby eliminating the need for extensive user oversight or manual parameter tuning. Our experiments across these four context levels reveal marked improvements in rotation accuracy, distance control, and overall layout plausibility compared with native VLM. By reducing the dependence on pre-programmed constraints or prohibitively large training sets, our method enables fully automated scene composition for both everyday scenarios and specialized cultural tasks, moving toward a universally adaptable framework for 3D arrangement.

cs.GR↗

arXiv2025

Experimental and Numerical Study of Acoustic Streaming in Mid-Air Phased Arrays

Mid-air acoustic streaming, where ultrasound induces steady fluid motion, could significantly affect the perception of haptic sensations, stability of levitation systems, and enable controlled transfer of odours (smells) through air by directing volatile compounds to specific locations. Despite its importance, the streaming behavior in airborne phased-array transducers remains poorly understood. Here, we use particle image velocimetry and numerical simulations to investigate streaming dynamics in single- and multi-focus acoustic fields. Experimental measurements reveal streaming velocities exceeding $0.4~\text{m/s}$ in single-focus configurations and up to $0.3~\text{m/s}$ in multi-focus setups, with distinct grating lobe-induced lateral jets. While multi-physics finite-element models effectively capture central streaming, they exhibit subtle differences and perform poorly in capturing flow in the side lobes. These findings provide valuable insights into the interplay between acoustic field design and streaming dynamics, offering guidance for optimizing ultrasonic technologies in haptics and levitation applications.

physics.app-ph↗

arXiv2025

AnimeGaze: Real-Time Mutual Gaze Synthesis for Anime-Style Avatars in Physical Environments via Behind-Display Camera

Avatars on displays lack the ability to engage with the physical environment through gaze. To address this limitation, we propose a gaze synthesis method that enables animated avatars to establish gaze communication with the physical environment using a camera-behind-the-display system. The system uses a display that rapidly alternates between visible and transparent states. During the transparent state, a camera positioned behind the display captures the physical environment. This configuration physically aligns the position of the avatar's eyes with the camera, enabling two-way gaze communication with people and objects in the physical environment. Building on this system, we developed a framework for mutual gaze communication between avatars and people. The framework detects the user's gaze and dynamically synthesizes the avatar's gaze towards people or objects in the environment. This capability was integrated into an AI agent system to generate real-time, context-aware gaze behaviors during conversations, enabling more seamless and natural interactions. To evaluate the system, we conducted a user study to assess its effectiveness in supporting physical gaze awareness and generating human-like gaze behaviors. The results show that the behind-display approach significantly enhances the user's perception of being observed and attended to by the avatar. By bridging the gap between virtual avatars and the physical environment through enhanced gaze interactions, our system offers a promising avenue for more immersive and human-like AI-mediated communication in everyday environments.

cs.HC↗

arXiv2025

Generative Artificial Intelligence-Guided User Studies: An Application for Air Taxi Services

User studies are crucial for meeting user needs. In user studies, real experimental scenarios and participants are constructed and recruited. However, emerging and unfamiliar studies face limitations, including safety concerns and iterative efficiency. To address these challenges, this study utilises a Generative Artificial Intelligence (GenAI) to create GenAI-generated scenarios for user experience (UX). By recruiting real users to evaluate this experience, we can collect feedback that enables rapid iteration in the early design phase. The air taxi is particularly representative of these challenges and has been chosen as the case study for this research. The key contribution was designing an Air Taxi Journey (ATJ) using Large Language Models (LLMs) and AI image and video generators. Based on the GPT-4-generated scripts, key visuals were created for the air taxi, and the ATJ was evaluated by 72 participants. Furthermore, the LLMs demonstrated the ability to identify and suggest environments that significantly improve participants' willingness toward air taxis. Education level and gender significantly influenced participants' the difference in willingness and their satisfaction with the ATJ. Satisfaction with the ATJ serves as a mediator, significantly influencing participants' willingness to take air taxis. Our study confirms the capability of GenAI to support user studies, providing a feasible approach and valuable insights for designing air taxi UX in the early design phase.

cs.HC↗

arXiv2025

Spatial Sound Modulation through Manual Reconfiguration of Phased Plate

Ultrasonic phased array technology, while versatile, often requires complex computing resources and numerous amplifier components. We present a Manually Reconfigurable Phased Array that physically controls transducer position and phase, offering a simpler alternative to traditional phased array transducers (PAT). Our system uses a conductor rod-connected transducer array with an underlying plate that modulates the phase state through its shape and electrode arrangement. This approach enables variable phase reconstruction with reduced computational demands and lower cost. Experimental results demonstrate the device's capability to focus ultrasonic waves at different spatial locations. The system's design facilitates the creation of acoustic fields without extensive digital control, potentially broadening applications in areas such as aerial haptics, audio spotlighting, and educational demonstrations of acoustic phenomena. This work contributes to the development of more accessible and computationally efficient acoustic phased array systems.

physics.app-ph↗

arXiv2024

Conditional neural holography: a distance-adaptive CGH generator

A convolutional neural network (CNN) is useful for overcoming the trade-off between generation speed and accuracy in the process of synthesizing computer-generated holograms (CGHs). However, methods using a CNN have limited applicability as they cannot specify the propagation distance when synthesizing a hologram. We developed a distance-adaptive CGH generator that can generate CGHs by specifying the target image and propagation distance, which comprises a zone plate encoder stage and an augmented HoloNet stage. Our model is comparable to that of prior CNN methods, with a fixed distance, in terms of performance and achieves the generation accuracy and speed necessary for practical use.

physics.optics↗

arXiv2024

See-Through Face Display: Enabling Gaze Communication for Any Face$\unicode{x2013}$Human or AI

We present See-Through Face Display, an eye-contact display system designed to enhance gaze awareness in both human-to-human and human-to-avatar communication. The system addresses the limitations of existing gaze correction methods by combining a transparent display with a strategically positioned camera. The display alternates rapidly between a visible and transparent state, thereby enabling the camera to capture clear images of the user's face from behind the display. This configuration allows for mutual gaze awareness among remote participants without the necessity of a large form factor or computationally resource-intensive image processing. In comparison to conventional methodologies, See-Through Face Display offers a number of practical advantages. The system requires minimal physical space, operates with low computational overhead, and avoids the visual artifacts typically associated with software-based gaze redirection. These features render the system suitable for a variety of applications, including multi-party teleconferencing and remote customer service. Furthermore, the alignment of the camera's field of view with the displayed face position facilitates more natural gaze-based interactions with AI avatars. This paper presents the implementation of See-Through Face Display and examines its potential applications, demonstrating how this compact eye-contact system can enhance gaze communication in both human-to-human and human-AI interactions.

cs.HC↗

arXiv2024

Expanding Horizons in HCI Research Through LLM-Driven Qualitative Analysis

How would research be like if we still needed to "send" papers typed with a typewriter? Our life and research environment have continually evolved, often accompanied by controversial opinions about new methodologies. In this paper, we embrace this change by introducing a new approach to qualitative analysis in HCI using Large Language Models (LLMs). We detail a method that uses LLMs for qualitative data analysis and present a quantitative framework using SBART cosine similarity for performance evaluation. Our findings indicate that LLMs not only match the efficacy of traditional analysis methods but also offer unique insights. Through a novel dataset and benchmark, we explore LLMs' characteristics in HCI research, suggesting potential avenues for further exploration and application in the field.

cs.HC↗

arXiv2023

Lottery and Sprint: Generate a Board Game with Design Sprint Method on AutoGPT

In this paper, we present a novel approach using the Auto GPT system alongside Design Sprint methodology to facilitate board game creation for inexperienced users. We introduce the implementation of Auto GPT for generating diverse board games and the subsequent optimization process through a customized Design Sprint. A user study is conducted to investigate the playability and enjoyment of the generated games, revealing both successes and challenges in employing systems like Auto GPT for board game design. Insights and future research directions are proposed to overcome identified limitations and enhance computational-driven game creation.

cs.HC↗

arXiv2023

SHITARA: Sending Haptic Induced Touchable Alarm by Ring-shaped Air vortex

Social interaction begins with the other person's attention, but it is difficult for a d/Deaf or hard-of-hearing (DHH) person to notice the initial conversation cues. Wearable or visual devices have been proposed previously. However, these devices are cumbersome to wear or must stay within the DHH person's vision. In this study, we have proposed SHITARA, a novel accessibility method with air vortex rings that provides a non-contact haptic cue for a DHH person. We have developed a proof-of-concept device and determined the air vortex ring's accuracy, noticeability and comfortability when it hits a DHH's hair. Though strength, accuracy, and noticeability of air vortex rings decrease as the distance between the air vortex ring generator and the user increases, we have demonstrated that the air vortex ring is noticeable up to 2.5 meters away. Moreover, the optimum strength is found for each distance from a DHH.

cs.HC↗

arXiv2023

HaptStarter: Designing Haptic Stimulus Start System for Deaf and Hard of Hearing Sprinters

In this study, we design and develop HaptStarter -- a haptic stimulus start system -- to improve the starting performance of the deaf and hard of hearing (DHH) sprinters. A DHH person has a physical ability nearly equivalent to hearing; however, the difficulties in perceiving audio information lead to differences in their performance in sports. Furthermore, the visual reaction time is slower than the auditory reaction time (ART), while the haptic reaction time is equivalent to it. However, a light stimulus start system is increasingly being used in sprint races to aid DHH sprinters. In this study, we design a brand-new haptic stimulus start system for DHH sprinters; we also determine and leverage an optimum haptic stimulus interface. The proposed method has the potential to contribute toward the development of prototypes based on the universal design principle for everyone (DHH, blind and low-vision, and other disabled sprinters with wheelchairs or artificial arms or legs, etc.) by focusing on the overlapping area of sports and disability with human-computer interaction.

cs.HC↗

arXiv2023

Dance Generation by Sound Symbolic Words

This study introduces a novel approach to generate dance motions using onomatopoeia as input, with the aim of enhancing creativity and diversity in dance generation. Unlike text and music, onomatopoeia conveys rhythm and meaning through abstract word expressions without constraints on expression and without need for specialized knowledge. We adapt the AI Choreographer framework and employ the Sakamoto system, a feature extraction method for onomatopoeia focusing on phonemes and syllables. Additionally, we present a new dataset of 40 onomatopoeia-dance motion pairs collected through a user survey. Our results demonstrate that the proposed method enables more intuitive dance generation and can create dance motions using sound-symbolic words from a variety of languages, including those without onomatopoeia. This highlights the potential for diverse dance creation across different languages and cultures, accessible to a wider audience. Qualitative samples from our model can be found at: https://sites.google.com/view/onomatopoeia-dance/home/.

cs.LG↗

arXiv2023

Towards Digital Nature: Bridging the Gap between Turing Machine Objects and Linguistic Objects in LLMMs for Universal Interaction of Object-Oriented Descriptions

In this paper, we propose a novel approach to establish a connection between linguistic objects and classes in Large Language Model Machines (LLMMs) such as GPT3.5 and GPT4, and their counterparts in high level programming languages like Python. Our goal is to promote the development of Digital Nature: a worldview where digital and physical realities are seamlessly intertwined and can be easily manipulated by computational means. To achieve this, we exploit the inherent abstraction capabilities of LLMMs to build a bridge between human perception of the real world and the computational processes that mimic it. This approach enables ambiguous class definitions and interactions between objects to be realized in programming and ubiquitous computing scenarios. By doing so, we aim to facilitate seamless interaction between Turing Machine objects and Linguistic Objects, paving the way for universally accessible object oriented descriptions. We demonstrate a method for automatically transforming real world objects and their corresponding simulations into language simulable worlds using LLMMs, thus advancing the digital twin concept. This process can then be extended to high level programming languages, making the implementation of these simulations more accessible and practical. In summary, our research introduces a groundbreaking approach to connect linguistic objects in LLMMs with high level programming languages, allowing for the efficient implementation of real world simulations. This ultimately contributes to the realization of Digital Nature, where digital and physical worlds are interconnected, and objects and simulations can be effortlessly manipulated through computational means.

cs.HC↗

arXiv2022

Kuchibashi: 3D-Printed Tweezers Bioinspired by the New Caledonian Crow's Beak

In this study we implemented Kuchibashi, the New Caledonian Crow beak-like tweezers, and conducted a user study to evaluate the prototype's usability. We proved that Kuchibashi is superior in interacting with large spherical objects than hands and tweezers. Also, impressions of security and safeness were perceived positively by the participants.

cs.HC↗