Tomihiro Utsumi

Dr. Tomihiro Utsumi

orcid

Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
17 May 2024 in Applied Sciences
Verified
Journal Article
Open access
PDF file
MLMin Lu
Min Lu
MAMasatoshi Arikawa
Masatoshi Arikawa
KOKohei Oba
Kohei Oba
KIKeiichi Ishikawa
Keiichi Ishikawa
YJYuhan Jin
Yuhan Jin
RSRyo Sato
Ryo Sato
This study presents a novel framework for improving indoor augmented reality (AR) navigation with modern smartphone technology, which is achieved by addressing two major challenges: managing large absolute coordinate spaces and reducing error accumulation in camera-based spatial tracking. Our contribution is significant in two ways. First, we integrate geofencing with indoor navigation by considering spatial tracking errors, timing for audio guidance, and dynamic 3D arrow visualization for effective local-to-global spatial coordinate transformation. This method achieves precise local positioning and seamlessly integrates with larger spatial contexts, overcoming the limitations of current AR systems. Second, we introduce a periodic image-based calibration approach to minimize the inherent error accumulation in camera-based tracking, enhancing accuracy over longer distances. Unlike prior studies focusing on individual technologies, our work explores the software architecture of indoor AR navigation by providing a comprehensive framework for its design and practical use. The practicality of our approach is validated through the implementation of a smartphone application at the Mineral Industry Museum of Akita University, highlighting the limitations of component technologies and demonstrating our framework’s effectiveness.

28 November 2024 in Electronics
Verified
Journal Article
Open access
PDF file
TUTomihiro Utsumi
Tomihiro Utsumi
MAMasatoshi Arikawa
Masatoshi Arikawa
This study presents a robust framework designed to address the limitations of passive infrared (PIR) sensors in home-based elderly monitoring, particularly focusing on false detections and sensor blind times, which compromise data accuracy. While PIR sensors are low-cost and privacy-preserving, their inherent inaccuracies hinder their use in reliable monitoring systems. To overcome these challenges, we propose a novel spatiotemporal data cleaning framework that integrates non-deterministic tracking (NDT) and late-binding adjustment (LBA). This framework enhances the quality and accuracy of sensor data by filtering out false positives and omissions through analysis of walking speed and sensor connectivity. Simulations demonstrated significant improvements in movement tracking accuracy, and real-world experiments involving three elderly participants further validated the framework’s practicality. The experiments confirmed that the proposed method can remove errors such as false positives and false negatives from PIR sensors. It can achieve 90% accuracy in tracking the movements of elderly people, highlighting the potential for this framework to be applied in the real world. The key scientific contribution of this research lies in the development of a scalable, non-wearable indoor tracking solution that reduces the need for dense sensor arrays, making it cost-effective and adaptable to existing infrastructure with minimal modifications. This framework contributes to advancing the field of indoor localization and offers a reliable solution for sensor-based monitoring systems, especially in elderly care, addressing the urgent needs of an aging global population.

13 November 2023
Verified
Conference Paper
Open access
ISIori Sasaki
Iori Sasaki
MAMasatoshi Arikawa
Masatoshi Arikawa
MLMin Lu
Min Lu
RSRyo Sato
Ryo Sato
TUTomihiro Utsumi
Tomihiro Utsumi
A circular geofence (CGF), a virtual boundary defined by a center point and a radius, plays a significant role in various location-based services. Our paper discusses the need for automatic generation of geofences due to the difficulties in creating adaptable settings for user movement and GPS sensor errors regarding one of the most typical mobile tour guide applications - a service helping city tourists discover nearby points of interest. Currently, human-created fixed CGFs sharing the same center point of points of interest have been generally adopted thanks to their intuitive nature and simplicity. However, our algorithm for automatic parameter determination based on tourists' GPS logs enables us to introduce flexible CGFs that can be placed independently of the position of actual geographic features. Our experimental study using a GPS dataset indicates that this new style of geofences could produce more relevant notifications for a maximum number of tourists.

Verified
Journal Article
Open access
PDF file
ISIori Sasaki
Iori Sasaki
MAMasatoshi Arikawa
Masatoshi Arikawa
MLMin Lu
Min Lu
TUTomihiro Utsumi
Tomihiro Utsumi
RSRyo Sato
Ryo Sato
This study proposes a method for generating geofences driven by GPS trajectory data to realize scalable point-of-interest (POI) notifiers, encouraging walking tourists to discover new local spots. The case study revealed that manual geofence settings degrade the location relevance and user coverage—key objectives of POI notifiers—and hinder the scalability and reliability of services. The formalization presented computationally equips geofence designers with practical solutions through two implementations based on prior GPS trajectory logs: (1) a multiobjective genetic algorithm that suggests cost-effective geofences by providing trade-off visualizations and (2) a user coverage-penalized genetic algorithm that determines an optimal geofence based on the designers’ expectations. The feasibility and stability of the proposed implementations were tested in areas with varying tourist flow patterns. A comparative survey among manual settings, settings incorporating a reliability simulation, and data-driven settings demonstrates significant performance improvements for geofence services.

8 July 2023 in Electronics
Verified
Journal Article
Open access
PDF file
TUTomihiro Utsumi
Tomihiro Utsumi
MAMasatoshi Arikawa
Masatoshi Arikawa
MHMasashi Hashimoto
Masashi Hashimoto
With the ageing of society, the number of households with older individuals or couples living alone is increasing. An “ageing-in-place” approach allows older adults to continue to live at home and receive help only when needed. However, this approach is insufficient for emergencies, such as falls, as well as for individuals with gradually deteriorating health conditions, such as frailty. Unexpected accidents significantly reduce the quality of life (QoL) of older adults. This paper proposes a new framework, the mobility ubiquitous sensor edge environment (MUS3E), to digitally transform ordinary houses to detect the movement of older individuals throughout their home environment and to notify family members and care providers of residents’ health status and safety information. The framework can be easily and inexpensively installed in any home, transforming an ordinary house into a smart home with an automated function for monitoring older residents. It uses ambient sensors such as passive infrared ray sensors to automatically measure health conditions by measuring factors such as walking speed. Residents need not interact with or control the system and can go about their daily lives. Since the sensors used in this system are mass-produced consumer products, they are inexpensive and easily replaceable, as there are many alternatives. In this study, we were able to demonstrate the practically and feasibility of this framework using a prototype that uses open architecture Internet of Things (IoT) software (Debian GNU/Linux 11, Arduino 1.8.19, ESP8266 2.7.4, ESP32 1.0.6, PubSubClient 2.8.0, ESPPerfectTime 0.3.0, mosquitto 2.0.11) components to digitally transform the living environment of older individuals.

21 September 2024
Verified
Conference Paper
Open access
ISIori Sasaki
Iori Sasaki
MAMasatoshi Arikawa
Masatoshi Arikawa
MLMin Lu
Min Lu
TUTomihiro Utsumi
Tomihiro Utsumi
RSRyo Sato
Ryo Sato
This study presents a geofence-based service architecture for city-wide audio augmented reality, tailored for the era of large language models. Traditional geofencing mechanisms, which monitor user entry to geofences, struggle to provide continuous storytelling in areas with few points of interest, degrading the audio tour experiences for pedestrians. Our proposed geofencing architecture consistently incorporates complex and multilayered city features, enabling seamless audio tour experiences. Furthermore, this paper introduces prompt engineering for generating entertaining guide scripts for large language models, that is, the geofence-to-conversation technique. The mobile application developed for the actual field demonstrates the feasibility of our proposed architecture and highlights future challenges in enhancing users’ interaction with a city.