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Papers - Ogawa, Ami

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Enhancing force plate design through optimization of spring constant distribution

Y Kawasaki, A Ogawa, H Takahashi

Sensors and Actuators A: Physical 374, 115468 (Elsevier BV) 374 115468 - 115468 2024.08

ISSN 09244247

Force plates have been widely used in various scientific fields to measure ground reaction forces experienced by animals and humans. A force plate that incorporates mechanical springs and non-contact displacement sensors offers the advantages of facilely modifying its shape and performance. However, the design protocol was limited to adjusting the plate size and spring constants of the springs supporting the plate at the four corners. Herein, we propose an optimization method for determining the spring constant distribution of a force plate. The proposed design enables the use of simulations to optimize the mechanical properties of the force plate, such as resonant frequency and error due to position. The experimental results demonstrated that the resonant frequency of the fabricated force plate was 133 Hz and the error due to position was within ±5 %. These results confirm that the proposed force plate can be effectively adjusted through optimization.

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Effect of particle size distribution on the transmission efficiency of atomized water to the tracheal tube

T Asakura, K Yoshioka, A Ogawa, Y Kurashina

Sensors and Actuators A: Physical 370, 115270 (Sensors and Actuators A: Physical) 370 2024.05

ISSN 09244247

Ultrasonic atomization is a widely used technology. As the atomization device, lead zirconate titanate (PZT) and lithium niobate (LN) are comparatively investigated through experimental and numerical schemes. However, knowledge on a profitable scheme by which to efficiently deliver the atomized particles into the tracheal tube remains unclear. In this study, the physical difference of the transmission efficiency of water particles atomized by PZT and LN devices was measured. The water particles atomized by PZT and LN were injected into a human airway model including a nasal cavity and bronchial tube. The distribution of the amount of transmitted particles deposited at each of the monitoring positions was then estimated using the results of image analysis of color intensity. As a result, the atomized particles of the PZT device, which produced larger particles than the LN device, were more strongly affected by inertia and tended to be deposited at the area closer to the entrance of the nasal cavity. In contrast, the particles produced by the LN device tended to be transmitted deeper into the trachea. The experimental results indicated that the particle size distribution of PZT and LN, which have quite different maximum sizes of particles, largely influences the spatial distribution characteristics of particle deposition along the airway from the nasal cavity to the trachea.

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ANALYSIS AND REAL-TIME PREDICTION OF 90 DEGREES TURNING MOVEMENTS DURING WALKING ASSUMING LIVING SPACE

Motoyama R., Kondo M., Ogawa A., Mita A.

Journal of Environmental Engineering (Japan) (Journal of Environmental Engineering (Japan)) 89 ( 818 ) 222 - 233 2024.04

ISSN 13480685

When introducing robots and sensors into living spaces, predicting turning movements while walking is an important element to ensure safety. In this study, we assumed a living space, set experimental conditions that did not interfere with the subjects' free movement, and measured natural turning movements. First, the parameters used for prediction were selected from the measured data. Then, using those parameters, he built a system that predicted 90-degree turning movements in real time. Finally, we verified the system. This research will contribute to the development and practical application of an analysis and prediction system for turning movements during walking.

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Trends, Challenges, and Opportunities in Assistive and Robotic Kitchen Technologies for Aging Society: A Scoping Review

R Hu, A Ogawa, BG de Soto, T Bock

41st International Symposium on Automation and Robotics in Construction … 561 - 568 2024

The world’s population is rapidly aging. According to the United Nations, nearly 10% of the world’s population is over 65 years old. The aging population crisis is arguably one of the most pressing challenges to the future well-being of humanity. The kitchen is an essential place for human activities, and cooking holds significant importance for older adults, serving as a key measure of their capacity for independent living. Moreover, it plays a crucial role in ensuring that older individuals receive the necessary nutrition to maintain good health. Naturally, the investigation of assistive kitchen technologies emerges as a compelling and significant field of research. However, there are no existing reviews that specifically address assistive kitchen and cooking technologies designed for vulnerable populations such as older adults or individuals with disabilities. Therefore, this paper provides a scoping review of the trends, challenges, and opportunities in emerging assistive kitchen and cooking technologies for the past decade. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis Extension for Scoping Reviews (PRISMA-ScR) methodology was adopted for the review. As a result, 100 peer-reviewed publications from 29 countries were included in this review. These studies cover six major research topics on assistive and robotic kitchens. As a result, the trends, challenges, and opportunities of the current technologies are analyzed, and a modular and adaptable smart kitchen is proposed. The study will fill the scientific gap and lay the groundwork for future development of assistive kitchen technology.

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Sampling Moiré Method Force Plate Utilizing Smartphone Camera

O Nomura, A Ogawa, H Takahashi

IEEE Sensors Letters (Institute of Electrical and Electronics Engineers (IEEE)) 8 ( 8 ) 1 - 4 2024

ISSN 2475-1472

Ground reaction force (GRF) is a significant factor for evaluating foot biomechanics, and force plates (FPs) are commonly employed for assessment. Conventional FPs feature an integrated design of a supporting structure and sensor elements but face the challenges of high cost and limited customizability. Recently, high-resolution triaxial force measurements have been conducted using a prism and sampling moiré (SM) method within an optical experimental setup. Herein, we propose an FP that utilizes a commercial smartphone and the SM method. The proposed design simplifies the FP configuration, which comprises mechanical spring structures, a simple optical setup, smartphone, and smartwatch. We constructed a prototype FP of 200 mm × 400 mm capable of force resolution under 1 N. Camera images from the smartphone displayed two inclined grating images (GIs) via the prism, accurately reflecting vertical force applications. In the experiment, the developed FP measured the GRF in a manner similar to that of a commercial FP during human walking. The proposed method is practical for developing high-performance FPs.

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Fit Islands: Designing a Multifunctional Exergame to Promote Healthy Aging for Chinese Older Adults

Z Shen, R Hu, D Wan, A Ogawa, T Bock

ISARC. Proceedings of the International Symposium on Automation and Robotics … 529 - 536 2024

Emerging economies are ill-prepared to deal with population aging. Uncontrollable events such as the COVID-19 pandemic and regional conflicts have exacerbated the plight of older adults. The consequent development of smart aging offers endless possibilities for improving the quality of life and health of older adults. In this paper, the authors propose a universal approach to designing a health-promoting Exergame system in the format of a virtual village for emerging economies to cope with aging populations. To verify the feasibility, the authors designed an expandable Exergame called "Fit Islands", using China as a case study. Based on the initial demonstration the authors conducted functional tests. The result is that Fit Islands can meet the development objective of motivating Chinese older people to increase their physical activity, providing initial evidence of the feasibility of an Exergame system to promote healthy aging in emerging economies. The application of Fit Islands demonstrates the feasibility of the universal Exergame development method, which can, in principle, provide comprehensive and practical guidance for other countries.

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A new roadmap for an age-inclusive workforce management practice and an international policies comparison

N Katiraee, N Berti, A Das, I Zennaro, R Aldrighetti, V Dimovski, D Peljhan, ...

Open Research Europe 4, 85 (F1000 Research Ltd) 4 85 - 85 2024

<p>Background Worldwide, the worker population age is growing at an increasing rate. Consequently, government institutions and companies are being tasked to find new ways to address age-related workforce management challenges and opportunities. The development of age-friendly working environments to enhance ageing workforce inclusion and diversity has become a current management and national policy imperative. Since an ageing workforce population is a spreading worldwide trend, an identification and analysis of worker age related best practices across different countries would help the development of novel palliative paradigms and initiatives. Methods This study proposes a new systematic research-based roadmap that aims to support executives and administrators in implementing an age-inclusive workforce management program. The roadmap integrates and builds on published literature, best practices, and international policies and initiatives that were identified, collected, and analysed by the authors. The roadmap provides a critical comparison of age-inclusive management practices and policies at three different levels of intervention: international, country, and company. Data collection and analysis was conducted simultaneously across eight countries: Canada, France, Germany, Italy, Japan, New Zealand, Slovenia, and the USA. Results and conclusions The findings of this research guide the development of a framework and roadmap to help manage the challenges and opportunities of an ageing workforce in moving towards a more sustainable, inclusive, and resilient labour force.</p>

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Augmented architectural space system for the creation of casual connections with people

Y Suetomi, A Ogawa

9th Asia-Pacific Workshop on Structural Health Monitoring, 9APWSHM 2022, 183-190 (Materials Research Proceedings) 27 183 - 190 2023

ISSN 24743941

In recent years, the increasing social isolation has become a major problem in Japan because of the growing trend toward nuclear families. In addition, further social isolation is concerned caused by a decrease on face-to-face communication opportunities due to the outbreak of the COVID-19 infection. Therefore, it is necessary to create connections among people. On the other hand, opportunities for people to communicate online have increased rapidly. However, various information obtained the face-to-face is missing online, which degrades the quality of communication and causes physical and mental fatigue to users. To solve these problems, this study aims to minimize the gap that exists between online and the face-to-face, and to propose an Augmented Architectural Space that creates casual connections between people within their living space. By comparing the results of impression evaluation experiments using questionnaires for the face-to-face environment, the video conferencing system environment, and the proposed system environment, we demonstrate the usefulness of the proposed Augmented Architectural Space system for creating casual connections between people.

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Modeling and utilizing habits using process mining for building spatial design systems

N Haraguchi, A Ogawa

9th Asia-Pacific Workshop on Structural Health Monitoring, 9APWSHM 2022, 103-110 (Materials Research Proceedings) 27 103 - 110 2023

ISSN 24743941

Residents need to change their habitual behaviors following living space changes, such as moving or remodeling, and that may occur mental stress. This stress is a major problem, especially for the elderly, who are less able to cope with changes in their environment. To reduce this stress, a system that reflects the living information of the original houses in new houses, where habits can be retained in the new environments is needed. Many studies have been conducted to quantify life information as a habitual model using data mining and pattern recognition methods. “Process Mining” is a theory developed to visualize and improve processes in the business field and applied to lifestyle information, and it is possible to create a habit model. In recent years, several studies on habit models using process mining have been reported. However, there are no studies in which these process mining-based habit models have been adopted to design architectural spaces such as living spaces. Therefore, the purpose of this study is to investigate the relationship between habit and architectural space by utilizing a process mining-based habit model. Specifically, we propose the automatic extraction and visualization of habit behaviors through process mining and the use of habit models. The data acquisition experiment was conducted in an experimental smart home. This smart home is a mobile trailer house built by a multi-company project and is equipped with many sensors that can automatically acquire many daily living data. Subjects were recruited randomly and lived alone in this smart home for one week. An input matrix was created from the acquired data set and process mining was adapted to create habit models. In this study, two habit models were created: (1) a habit model based on behavioral information and (2) a habit model based on location information. Each input matrix consisted of (1) 16 types of behavior record data manually entered by the subject and (2) ground reaction force data in the house divided into 7 areas. We investigated the relationship between habitual behaviors and spatial conditions by integrating these two models.

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Evaluation of a practical automatic damage assessment system using a single accelerometer for wooden frame houses

Y Furukawa, K Horita, A Mita, A Ogawa

9th Asia-Pacific Workshop on Structural Health Monitoring, 9APWSHM 2022, 143-149 (Materials Research Proceedings) 27 143 - 149 2023

ISSN 24743941

In recent years, Structural Health Monitoring (SHM) has been attracting more attention as a method to determine the existence of the damage and its extent. The typical SHM system employs many sensors to assess the damage quantitatively and qualitatively. However, such a system is not appropriate for wooden houses as it is very costly despite the strong demand. Therefore, developing a low-cost SHM system for wooden houses is necessary. We have been working on algorithms that automatically determine the degree of damage from the maximum inter-story drift angle and natural frequencies using two accelerometers and evaluate the accuracy of the results by applying them to full-scale shake table experimental data.[1] Then, we evolved the system to use only a single accelerometer. In this advanced method, we estimate the first natural frequency without being annoyed by the fundamental frequency of ground motion, which often deteriorates frequency estimation accuracy. In this paper, we demonstrate the applicability of the SHM system using only one sensor in practical scenarios. Firstly, we examined the proposed method using only one accelerometer through the simulation approach. Secondly, we test the system's applicability utilizing a series of large-scale shake table test data. Finally, we examine this method's validity and economic feasibility, contributing to cost reduction and simplification of the algorithm for practical use.

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Effects of architectural space design on predicting turning in daily life

Y Matsunami, R Motoyama, M Miyaguchi, M Kondou, A Ogawa

9th Asia-Pacific Workshop on Structural Health Monitoring, 9APWSHM 2022, 127-134 (Materials Research Proceedings) 27 127 - 134 2023

ISSN 24743941

In recent years, the diversification of lifestyles and the increase in the number of elderly single-person households have increased the need to introduce robots and sensors into living spaces to control living spaces appropriately for individuals. To realize these goals, it is necessary to predict people’s non-steady motions which is one of the challenges in introducing robots into living spaces. In response, we have conducted research on motion prediction systems using robots and sensors. These studies will contribute to the realization of safe and comfortable architectural spaces by introducing robots into living spaces and collaborating with various space controls such as automatic doors and lighting. In this study, we focused on turning related to walking, which is the most basic motion in activities of daily living. As turning is a non-steady motion greatly affected by aging and disease, it is difficult to predict while is highly useful as a health indicator. Previous studies have suggested that architectural space design can influence the prediction of turning, but the actual effects are not clear because these studies were conducted only under highly constrained conditions in a laboratory environment. Thus, existing systems for predicting turning have not been validated in daily living environments due to issues such as instructions of motions to participants, limitations of natural motions because of contact sensors, and validation in experimental environments that are specially prepared to ensure reproducibility. Therefore, the purpose of this study was to introduce our sensing systems into actual living spaces and to validate our turning prediction system using acquired data on participants’ natural motion. In addition, the influence of architectural space design on predicting turning was clarified by conducting an experiment at a T-junction with an open space and a crossroad with poor visibility. In this study, an office space was selected as the experimental field as a living space to verify the feasibility of our turning prediction system.

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接触情報のリハビリテーション医療への応用

野崎貴裕，小川愛実

The Japanese Journal of Rehabilitation Medicine 60 (11), 966-973 2023

座面の硬さが立ち上がり動作に与える影響

小川愛実，尾嵜光太

生体医工学, 211_2-211_2 2023

An optimal sensor placement method for physical function assessment in living space

M Yamane, A Ogawa

Materials Research Proceedings 27 2023

A comprehensive analysis of sit‐to‐stand movement in a living space involving principal component analysis

N Haraguchi, A Ogawa, A Mita

Japan Architectural Review 6 (1), e12324 2023

Identification of Early Knee Osteoarthritis Based on Knee Joint Trajectory during Stair Climbing

A Ogawa, H Iijima, M Takahashi

International Journal of Environmental Research and Public Health 19 (22), 15023 (International Journal of Environmental Research and Public Health) 19 ( 22 ) 2022.11

ISSN 16617827

Patients with knee osteoarthritis show low stair climbing ability, but a diagnosis of stair performance time is not enough to identify the early stages of knee osteoarthritis. Therefore, we developed an indicator named range of the knee joint trajectory (RKJT) as a kinematic parameter to express more detailed characteristics than stair performance time. To achieve this, we used our developed “IR-Locomotion”, a markerless measurement system that can track the knee joint trajectory when climbing stairs. This study aimed to test whether the RKJT effectively identifies patients with early knee osteoarthritis even after controlling stair performance time. Forty-seven adults with moderate to severe knee pain (mean age 59.2 years; 68.1% women) underwent the radiographic examination (Kellgren and Lawrence grade) of both knees and a stair climbing test on 11 stairs. The RKJT during the stair climbing test was calculated by “IR-Locomotion”. A generalized linear mixed model was used to evaluate the discriminative capability of RKJT on early knee osteoarthritis (i.e., Kellgren and Lawrence grade of 1). As expected, patients with early knee osteoarthritis showed larger RKJT than non-radiographic controls (95% confidence interval: 1.007, 1.076). Notably, this finding was consistent even after adjusting stair performance time.

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Effect of the area of a lithium niobate transducer on the efficiency of ultrasonic atomization driven by resonance vibration

K Yoshioka, Y Kurashina, A Ogawa, T Asakura

Ultrasonics Sonochemistry 86, 106019 (Ultrasonics Sonochemistry) 86 106019 2022.05

ISSN 13504177

In recent years, individual control of one's personal environment has been drawing increasing attention due to the growing interest in health care. Wearable devices are especially useful because of their controllability regardless of location. Humidity is one of the inevitable factors in the personal environment as a preventive against infectious diseases. Although atomization devices are commonly used as a method of humidity control, at present, there are no wearable humidity control devices. Vibration of a lithium niobate (LN) device in the thickness mode is a promising piezoelectric method for miniaturization of atomization devices for humidity control. To miniaturize the atomization device, the transducer size needs to be small not so much as to decrease the atomization efficiency. However, the effect of the device area on the atomization efficiency of LN at a size suitable for mounting in wearable devices has not been studied. Here, we conducted an atomization demonstration of LN devices with different sizes to evaluate particle size and atomization efficiency. Furthermore, to reveal the relationship between vibration behavior and atomization efficiency, resonance vibration in the MHz frequency band was evaluated by the finite element method and an impedance analyzer. The results showed that the peak size of water particles atomized by each device was in the range of 3.2 to 4.2 µm, which is smaller than particles produced by typical piezoelectric ceramics. Moreover, the best LN size for efficient atomization was found to be 8 mm × 10 mm among the five LN device sizes used in experiments. From the relationship between vibration behavior and atomization efficiency, the size of the transducer was suggested to affect the vibration mode. The obtained result suggested that the LN device is suitable for small wearable nebulizer devices.

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PREDICTION OF WALKING TURNS FOCUSING ON THE CENTER OF GRAVITY

Sugimoto N., Ogawa A., Mita A.

AIJ Journal of Technology and Design (AIJ Journal of Technology and Design) 28 ( 68 ) 510 - 514 2022.02

ISSN 13419463

This study revealed proper parameters to predict walking turns to-support the residents as a built environment function. We used a non contact sensor that did not disturb everyday life and aimed to extract highly versatile prediction parameters by considering the movement strategy and the rotation direction. After carefully examining the prediction accuracy for the center-of-gravity shift and the head and upper body rotation parameters, we found the position of the head’s center-of-gravity (Left-Right) and the head rotation (Yaw) were valuable indicators. The time needed for prediction was between 0.18 to 0.48 steps with a prediction accuracy of 70%.

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主成分分析を用いた居住空間における立ち上がり動作の包括的分析

原口直大，小川愛実，三田彰

日本建築学会環境系論文集 87 (794), 282-290 2022

A COMPREHENSIVE ANALYSIS OF SIT-TO-STAND MOVEMENT IN A LIVING SPACE INVOLVING PRINCIPAL COMPONENT ANALYSIS

Haraguchi N., Ogawa A., Mita A.

Journal of Environmental Engineering (Japan) (Journal of Environmental Engineering (Japan)) 87 ( 794 ) 282 - 290 2022

ISSN 13480685

The analysis of Sit-to-Stand (STS) movement can lead to the early detection of a decline in physical functioning. The present study clarified the differences between age groups in common STS movements of daily life. We measured the three patterns of STS movement assumed to be performed in living spaces. Principal component analysis was applied to the overall time series data. From the synthesized principal component space, principal components with significant differences between the elderly and young adults were extracted, and the movement strategies of elderly participants were revealed.

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