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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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Identification of Disease-Specific Turning Movement Hallmarks: A Systematic Review towards Establishment of Disease Screening Algorithm

A Ogawa, T Takeda, K Yoshino, H Iijima

medRxiv, 2022.05. 27.22275714 (Cold Spring Harbor Laboratory) 2022

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非接触変位センサとばねを用いたフォースプレートの開発

川�ア裕太，小川愛実，高橋英俊

シンポジウム: スポーツ・アンド・ヒューマン・ダイナミクス講演論文集 2022, B-5-1 2022

ばね構造とセンサ素子を用いた 4 軸フォースプレート

川�ア裕太，小川愛実，高橋英俊

ロボティクス・メカトロニクス講演会講演概要集 2022, 2P1-T02 2022

Force Plate with Simple Mechanical Springs and Separated Noncontact Sensor Elements

Y Kawasaki, A Ogawa, H Takahashi

Sensors 21 (21), 7092 (Sensors) 21 ( 21 ) 2021.11

ISSN 14248220

This paper reports on a force plate (FP) using mechanical springs and noncontact distance sensors. The ground reaction force (GRF) is one of the factors for clarify biomechanics, and FPs are widely used to measure it. The sensor elements of conventional FPs are mainly strain gauges. Thus, the mechanical properties of FP depend on the sensor element performance. If the FP performance must change, we must redesign the FP, including changing the sensor elements. Here, we proposed an FP that uses a measuring principle based on simple springs and noncontact sensors. The shape and performance of the proposed FP are expected to change easily. As a prototype device, we designed and fabricated an FP installed with 12 springs and four sensors for human walking. A planar coil and magnet were used as the sensor elements, and the sensor output was proportional to the vertical and horizontal displacements. The FP resonance frequency was 123 Hz, which was larger than the required specification. The calibration experiments showed that vertical and horizontal forces and moments could be measured independently. The FP’s resolutions were 1.9 N and 1.4 N in the anterior–posterior and vertical directions, respectively. Furthermore, the fabricated FP measured GRF similarly to the commercial FP when a human walked on the plate. These results suggest that the proposed method will be helpful for FPs with custom-made requirements.

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Staircase design for health monitoring in elderly people

A Ogawa, H Iijima, M Takahashi

Journal of Building Engineering 37, 102152 (Elsevier {BV}) 37 102152 - 102152 2021.05

Research paper (scientific journal), Joint Work, Accepted, ISSN 2352-7102

The need for early detection and intervention for age-related health deterioration via home-based health monitoring systems is growing with global population aging. Health deterioration is typically evaluated using questionnaires, but obtaining frequent responses is difficult. Although stair walking involving a high physical load is suitable for assessing health deterioration, uniform assessment using home-based systems is difficult because different stair designs result in different movements. There is currently insufficient research on differences in evaluation performance between different stair designs. The current study aimed to develop an objective index to assess difficulties in activities of daily living (ADLs) as an indicator of health deterioration by observing stair walking, and to investigate the effects of stair dimensions on the relationship between the index and health deterioration. We hypothesized that knee joint positions during stair ascent would be associated with health deterioration, and developed the “Stepping in Level” index, reflecting the knee joint position when stepping in, obtained using a markerless depth information-based system. Seventy elderly people ascended two types of stairs (steep: 33.7°; shallow: 28.2°) and completed a questionnaire regarding ADL difficulty. We used a generalized linear mixed model to investigate the ability of “Stepping in Level” to explain ADL difficulty. The results revealed that “Stepping in Level” was able to explain ADL difficulty, and steep stairs were more suitable than shallow stairs for assessment. Our system enables daily assessment of difficulty in ADLs and detection of subtle changes in daily life. The current findings could inform design guidelines for health monitoring.

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Optimal Waiting Position of a Home Robot for Risk Communication Considering Behavior Patterns of an Occupant

A Mita, K Watanabe, A Ogawa

8th Asia-Pacific Workshop on Structural Health Monitoring, APWSHM 2020, 211-216 (Materials Research Proceedings) 18 ( 2021 ) 211 - 216 2021

Research paper (international conference proceedings), Joint Work, Accepted, ISSN 9781644901304

The risk communication in a home between a home robot and an occupant must be smooth in a way that the home robot does not disturb the occupant lives. In this paper, we propose a new method to determine the optimal waiting position considering the personal space and the obstacles such as furniture and the occupant’s walking patterns. It is shown that the distance to the wall from the occupant in the direction of the home robot and the standing or sitting posture affect most on the personal space. Furthermore, this personal space is dependent on each individual preference. The performance of the proposed method is much more feasible compared with those obtained in our previous approach.

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Extraction of Parameters for 90-degree Turn Prediction Using the IMU-based Motion Capture System

A Ogawa, K Takeda

Materials Research Proceedings 18 (Materials Research Proceedings) 18 ( 2021 ) 241 - 248 2021

Research paper (international conference proceedings), Joint Work, Accepted, ISSN 9781644901304

Against the increasing number of single households, we have been proposing the “Biofied Building” that provides a safe, secure, and comfortable living space for a resident using a small home robot. The robot can be used for real-time sensing of the resident’s position and behavior. On the other hand, for further use of the robot, such as choosing a path that does not disturb the resident, a phase to predict the resident’s behavior is necessary. Walking, which is one of the most basic activities of daily living, is often targeted in studies of motion prediction. However, most of them deal with steady walking, even though walking in daily life includes unsteady walking such as the turning motion. Therefore, the purpose of this study was to extract the prediction parameters to construct a prediction method for the unsteady 90-degree turn. In this study, we explored the effective prediction parameters for 90-degree turns based on the measured data using the inertial measurement unit (IMU) based motion capture system aiming to introduce the prediction of unsteady walking to the “Biofied Building”.

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Changes in Center of Mass during Preliminary Motion for Prediction of Direction Change

N Sugimoto, A Ogawa, A Mita

8th Asia-Pacific Workshop on Structural Health Monitoring, APWSHM 2020, 287-293 (Materials Research Proceedings) 18 ( 2021 ) 287 - 293 2021

Research paper (international conference proceedings), Joint Work, Accepted, ISSN 9781644901304

In recent years, the number of single elderly people has been increasing, and the needs of residents have been diversifying. Towards these backgrounds, we propose the concept of "Biofied bulding". The aim of Biofied Building is to create living spaces where residents can live safely, securely and comfortably. Small robots are used as an interface between residents and living space in Biofied Building. The aim of using robots is to sense the position and movement of residents in real time and providing feedback to them. However, the present control systems of the robot do not have enough functions to estimate the risk of accidents such as falls and choose the pathways which do not disturb residents. Therefore, the purpose of this research is to recognize and predict human behavior in a living space by using a robot to realize Biofied Building. In particular, we focus on the direction change motion, which is an important behavior in a living space, and extract the prediction parameters. In particular, it is reported that the direction change motion account for about 20% of gait during the daily life. Therefore, our research group decided to focus on direction change motion. In this study, we focused on the center of the head to extract parameters for prediction of the direction change motion. There are features in the velocity change of the center of the head compared with straight-line gait. There was a velocity amplification of the opposite direction of the direction change before the start of the motion. It is assumed that the shift of the center of mass make it to easier to step out to the direction of the turn.

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立ち上がり動作の質的評価

小川愛実

生体医工学, 541-541 (Japanese Society for Medical and Biological Engineering) Annual59 ( Abstract ) 541 - 541 2021

ISSN 1347-443X

Assessment systems of people's daily health are getting attention with the global population aging. This study proposes a qualitative evaluation method for the sit-to-stand motions which are frequently performed in daily life but are also highly challenging.Even if the amount of activity, which is easy to be measured, is appropriate, the motion might place an excessive load on a specific part of the body and damage. Thus, it is necessary to design an ideal motion in which the load is distributed to the entire body.Mechanical energy transfer efficiency has been proposed as an index to show the optimality of the motion, but it is limited to a limited evaluation using average or peak values and lacks a temporal element. This study proposes a new index that quantitatively evaluates the continuity of sit-to-stand motions by focusing on the temporal changes of parameters during the motions.

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センサ素子とばねに分離した可搬型フォースプレートの開発

川�ア裕太，小川愛実，高橋英俊

ロボティクス・メカトロニクス講演会講演概要集 2021, 2P2-I01 (The Japan Society of Mechanical Engineers) 2021 2P2-I01 2021

Ground reaction forces (GRF) are one of the important issues to investigate the kinetic characteristics of motion. In general, force plates, which are composed of a plate and force sensors, have been used for measurement of GRF. The measurement method will be useful for various types of walking situation and other animals. However, to specialize the force range for such targets, it is necessary to redesign from the force sensor in each case. Here, this paper presents a two-axis force plate with planar coils as the sensor elements and mechanical springs. By supporting the plate with springs and measuring the displacement of the plate with non-contact sensors, the mechanical performance does not depend on the sensing elements. Therefore, the proposed device realizes it easy to change the force range by replacing the springs. The fabricated device was evaluated in terms of sensitivity and position error.

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ESTIMATION OF THE OPTIMAL WAITING POSITION OF A HOME ROBOT BASED ON THE BEHAVIOR PATTERNS OF RESIDENTS TO FACILITATE HUMAN-ROBOT COMMUNICATION

Keita WATANABE, Ami OGAWA, Akira MITA

Journal of Architecture and Planning (Transactions of AIJ) (Architectural Institute of Japan) 85 ( 778 ) 2529 - 2538 2020.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 1881-8161

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Prediction of 90-degree turn using kinematic parameters for implementation of home robot

K Takeda, A Ogawa, A Mita

Journal of Environmental Engineering (Japan) 85 (778), 1027-1036 (Architectural Institute of Japan) 85 ( 778 ) 1027 - 1036 2020.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 13480685

Presently, social trends are indicating that single elderly households are increasing while lifestyles are diversifying. This paper proposes the Biofied building concept. In Biofied buildings, home robots provide a safe, secure, and comfortable space for residents. The objective of introducing robots is to sense a resident’s position and movement in real-time. However, with the existing system, it is difficult to prevent unexpected accidents and control robots without disturbing the residents. The objective of this study was to incorporate the motion prediction phase into the system and realize more natural spatial control using robots.

Although a simple motion prediction method based on dynamics using system identification has been proposed by a previous study, this cannot be applied to non-steady motion. Hence, it is necessary to extend the system such that it can be applied to various behaviors observed on a daily basis because the nonlinear behavior is not versatile. Particularly, with regard to walking motion, it has been reported that more than 40% of walking motions in daily life are non-steady, and the 90-degree turn accounts for approximately 20% of non-steady motions. Thus, the 90-degree turn was selected as the prediction target, because it is a basic non-steady walking motion and the most essential motion in daily life.

This study investigated the effectiveness of IMU sensors in measuring movements with complicated posture control. Notably, these sensors are inexpensive and not restricted by the measurement environment; therefore, the proposed method was developed based on data obtained using IMU sensors.

The kinematic parameters extracted in the preliminary experiment are useful for predicting the 90-degree turn by comparing steady walking to the 90-degree turn. Through comprehensive observations, the yaw and roll of the head and upper trunk, and the acceleration of shoulders and shanks, were extracted as the prediction parameters.

The 90-degree turn, which was performed at the subject’s own time and according to their free will, was measured to validate the prediction of parameters under the condition wherein the environmental and mental effects are eliminated. The prediction method was developed using the threshold defined by the amplitude during steady walking. The proposed method was evaluated by considering the prediction accuracy and prediction time. The fastest prediction time of 0.85 seconds was that of the yaw angular velocity at the head, and it was possible to predict it at least one step earlier.

Finally, the dependence of parameters on environmental factors was verified by conducting the same experiment at a corner. Compared with the previous experiment, only the response of the yaw angular velocity at the head was significantly faster, which suggests that this parameter depends on environmental factors. The yaw angular velocity at the head was the best predicted parameter with 100% success in each case. Hence, the motion is more likely to be predicted when the prediction time is longer, because the 90-degree turn is often performed at corners.

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Research on Motion Prediction in a House using a Markerless and Non-contact Sensor

Y KIMURA, AMI OGAWA, A MITA

日本建築学会技術報告集 (Web) 26 (63), 793-797 (Architectural Institute of Japan) 26 ( 63 ) 793 - 797 2020.06

Research paper (scientific journal), Single Work, Accepted, ISSN 13419463

Biofied building is a building system that provides safe, secure and comfortable space for residents using a robot. The robot acquires the motions and positions of residents. However, it is difficult to control the robot not to disturb the residents’ activities. The purpose of this research is to incorporate motion prediction in addition to motion recognition. Many of the conventional methods use RNN (Recurrent Neural Networks), which is difficult to implement due to the necessity of big data and large calculation cost. Thus, we aim to propose a simple motion prediction method using a human body model based on dynamics.

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PATH PLANNING IN RESIDENTIAL SPACE OF HOME ROBOT INCORPORATING WAITING BEHAVIOR

Ami Ogawa

AIJ Journal of Technology and Design (AIJ Journal of Technology and Design) 26 ( 62 ) 407 - 411 2020.02

Research paper (scientific journal), Single Work, Accepted, ISSN 13419463

© 2020 Architectural Institute of Japan. All rights reserved. We have been suggesting “Biofied Building” that provides the resident’s healthy life by introducing a small sensor agent robot into the house. The robot acquires the physical information of the resident and also acts as a communication robot. In the conventional motion flow, the robot always keeps following the resident. In this method, there are concerns about the risk of collision accidents with the resident or furniture and discomfort due to the behavior of the robot. Thus, we propose a path planning method incorporating waiting behavior in the motion flow of the robot in this research.

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待機行動を組み込んだ家庭用ロボットの居住空間内経路計画

木村拓未，小川愛実，三田彰

日本建築学会技術報告集 26 (62), 407-411 2020

マーカレスで非接触なセンサを用いた住宅内での動作予測に関する研究

木村洋介，小川愛実，三田彰

日本建築学会技術報告集 26 (63), 793-797 2020

居住者とロボットとのコミュニケーションを促進する居住者の行動パタンに基づく家庭用ロボットの最適待機場所推定

渡部敬太，小川愛実，三田彰

日本建築学会計画系論文集 85 (778), 2529-2538 2020

家庭用ロボット導入のための運動学的パラメタを用いた 90° 方向転換動作の予測

武田佳奈子，小川愛実，三田彰

日本建築学会環境系論文集 85 (778), 1027-1036 2020

11069 見守り支援ロボット導入のための運動学的パラメタを用いた方向転換動作の予測

武田佳奈子，小川愛実，三田彰

情報システム技術, 149-150 ( 2020 ) 149 - 150 2020

5565 人とロボットとのコミュニケーションを考慮した人の行動パターンに基づく家庭用ロボットの最適滞在位置推定

小川愛実，渡部敬太，三田彰

建築計画, 1133-1134 ( 2020 ) 1133 - 1134 2020

11099 PC 内蔵カメラを用いたリアルタイム集中力推定手法の提案と評価

福場凜太郎，小川愛実，三田彰

情報システム技術, 209-210 ( 2020 ) 209 - 210 2020

11098 非接触かつマーカレスなセンサを用いた関節トルクの推定および座位姿勢の力学的評価

國分萌々子，小川愛実，三田彰

情報システム技術, 207-208 ( 2020 ) 207 - 208 2020

床反力データを用いない下肢関節角度を入力とした膝関節モーメント推定

小川愛実，三田彰，佐藤貢一，石井喬之

Dynamics & Design Conference 2019, 458 (The Japan Society of Mechanical Engineers) 2019 458 2019

The joint moment is effective for quantitative physical load evaluation. We normally solve the joint moment by inverse dynamics with ground reaction force. However, a force plate which acquires ground reaction force data is too expensive for daily use. In this paper, we present a simple model for joint moment calculation based on the slope deflection method which does not require ground reaction force. We focused on a knee joint for basic study as it can be assumed to be a hinge joint. We estimated the knee joint moment during steady state walking and validated with three-dimensional motion analysis and force plate.

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たわみ角法を用いた定常歩行時の膝関節モーメントの推定に関する基礎検討

小川愛実，三田彰

生体医工学, S233_2-S233_2 (公益社団法人日本生体医工学会) Annual57 ( Abstract ) S233_2 - S233_2 2019

ISSN 1347-443X

高齢化に伴い予防医療の重要性が高まっている。生活自立度の維持において特に重要な運動機能の評価指標として歩行評価が広く実施されている。中でも歩行時の関節モーメントは部位毎の筋活動を反映しており、各関節にかかる負荷を定量的に示すことが可能である。関節モーメントは一般に床反力計および三次元動作解析装置を用いて計測される床反力情報と関節角度情報を剛体リンクモデルに代入することで求められる。しかし、医療機関などの計測環境では自然な歩行を取得することが難しく、日常的に行われる歩行を把握することが困難である。そこで本研究では居住空間で日常的に関節モーメントの計測を行うため、居住空間への導入が困難な床反力計を用いない手法を提案する。建築の構造計算に用いられるたわみ角法を用いた関節モーメント推定手法を新たに考案し、その基礎検討として膝関節モーメントにおいて従来手法による推定値と比較を行った。提案モデルでは関節角度のみを入力として膝関節モーメントを推定可能であり、三次元動作解析装置と床反力計から算出した値と高い相関を示した。今後は被験者を増やし、更なる検討を重ねたい。

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居住者の健康な生活を支援するための歩行パラメタ推定に関する研究 (本文)

小川愛実

慶應義塾大学 2019

11069 非接触センサを用いた定常歩行動作および立ち上がり動作の予測

小川愛実，木村洋介，三田彰

情報システム技術, 153-154 ( 2019 ) 153 - 154 2019

Usability evaluation of a gait monitoring robot in a living space

A Ogawa, A Mita

Journal of Environmental Engineering (Japan) 83 (752), 801-810 (Journal of Environmental Engineering (Japan)) 83 ( 752 ) 801 - 810 2018.10

Research paper (scientific journal), Joint Work, Accepted, ISSN 13480685

© 2018 Architectural Institute of Japan. All rights reserved. We have been suggesting a gait monitoring system using a small sensor agent robot. This system estimates knee joint positions and heel positions in order to detect the decline of the residents' physical performances in an early stage in living spaces. However, its accuracy has not been evaluated, and its performance in a real living environment has not been tested. In this paper, (1) we examined the important gait parameters to be monitored, (2) evaluated our system using a 3D motion analysis, and (3) considered the usability of our system in a real living environment.

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11037 居住空間における見守りロボットの人追随に関する研究

小川愛実，三田彰

情報システム技術, 73-74 ( 2018 ) 73 - 74 2018

居住空間における歩行見守りロボットの有用性の検証

小川愛実，三田彰

日本建築学会環境系論文集 83 (752), 801-810 2018

Performance of a Sensor Agent Robot in a Real Living Environment for Monitoring in Houses

A Ogawa, A Mita

Proceeding of International Conference on Smart, Sustainable and Sensuous … 2018

Markerless knee joint position measurement using depth data during stair walking

Ami Ogawa, Akira Mita, Ayanori Yorozu, Masaki Takahashi

Sensors (Switzerland) 17 ( 11 ) 2017.11

Accepted, ISSN 1424-8220

© 2017 by the authors. Licensee MDPI, Basel, Switzerland. Climbing and descending stairs are demanding daily activities, and the monitoring of them may reveal the presence of musculoskeletal diseases at an early stage. A markerless system is needed to monitor such stair walking activity without mentally or physically disturbing the subject. Microsoft Kinect v2 has been used for gait monitoring, as it provides a markerless skeleton tracking function. However, few studies have used this device for stair walking monitoring, and the accuracy of its skeleton tracking function during stair walking has not been evaluated. Moreover, skeleton tracking is not likely to be suitable for estimating body joints during stair walking, as the form of the body is different from what it is when it walks on level surfaces. In this study, a new method of estimating the 3D position of the knee joint was devised that uses the depth data of Kinect v2. The accuracy of this method was compared with that of the skeleton tracking function of Kinect v2 by simultaneously measuring subjects with a 3D motion capture system. The depth data method was found to be more accurate than skeleton tracking. The mean error of the 3D Euclidian distance of the depth data method was 43.2 ± 27.5 mm, while that of the skeleton tracking was 50.4 ± 23.9 mm. This method indicates the possibility of stair walking monitoring for the early discovery of musculoskeletal diseases.

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A face recognition system for automated door opening with parallel health status validation using the kinect v2

A. Ogawa, A. Mita, C. Georgoulas, T. Bock

ISARC 2016 - 33rd International Symposium on Automation and Robotics in Construction 132 - 140 2016

Accepted

Nowadays it is said that extending the healthy life expectancy is important in the aging society target group. Of course it is important for every singleperson household to be regularly checked upon their safety, but especially for elderly people the importance is higher at the point of healthy living, because this particular target group comprises a higher accidents rate. Therefore, the authors here propose the design and implementation of an unobtrusive vision system for single-person households, particularly for elderly people, based on the Microsoft Kinect v2. The entrance area of the home environment is here considered, where the monitoring system is activated upon while the user approaches, in order to first detect and calculate the user's fatigue levels, as well as to secondly identify the user by facial recognition, in order to actuate a door opening mechanism. The proposed system algorithm is divided into two distinct phases. The first phase concerns the acquisition of the user knee position while walking up a staircase in order to calculate fatigue. The second phase comprises the face recognition based door opening method. The proposed system has been successfully tested, and it could undoubtedly comprise an unobtrusive health status validation and automated door opening solution for elderly people in single-person households.

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Human activity recognition based on the activity categorization using depth data for "biofied building"

Ami Ogawa, Akira Mita

Journal of Environmental Engineering (Japan) (Architectural Institute of Japan) 81 ( 722 ) 403 - 410 2016

Accepted, ISSN 1348-0685

The number of single households is gradually increasing in Japan. The majority of them are consisting of elderly people. The "Biofied Building" that can monitor and control living spaces will help those people in many aspects. One of the key items to be acquired is the information about the residents activity. In this paper, we suggest an activity recognition method for two categories of activities, "Single type" and "Multiple type." We use the consecutive depth data obtained by Kinect. The R transformation, variance, PCA, LDA, and k-means classification are used for classification. Ten activities data sets consisting of six "Single type" and four "Multiple type" conducted by eleven subjects are used for verification.

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Gait parameters extraction by using mobile robot equipped with Kinect v2

Ami Ogawa, Akira Mita, Ayanori Yorozu, Masaki Takahashi

Proceedings of SPIE - The International Society for Optical Engineering 9803 2016

Accepted, ISSN 0277-786X

© COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only. The needs for monitoring systems to be used in houses are getting stronger because of the increase of the single household population due to the low birth rate and longevity. Among others, gait parameters are under the spotlight to be examined as the relations with several diseases have been reported. It is known that the gait parameters obtained at a walk test are different from those obtained under the daily life. Thus, the system which can measure the gait parameters in the real living environment is needed. Generally, gait abilities are evaluated by a measurement test, such as Timed Up and Go test and 6-minute walking test. However, these methods need measurers, so the accuracy depends on them and the lack of objectivity is pointed out. Although, a precise motion capture system is used for more objective measurement, it is hard to be used in daily measurement, because the subjects have to put the markers on their body. To solve this problem, marker less sensors, such as Kinect, are developed and used for gait information acquisition. When they are attached to a mobile robot, there is no limitation of distance. However, they still have challenges of calibration for gait parameters, and the important gait parameters to be acquired are not well examined. Therefore, in this study, we extract the important parameters for gait analysis, which have correlations with diseases and age differences, and suggest the gait parameters extraction from depth data by Kinect v2 which is mounted on a mobile robot aiming at applying to the living environment.

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Consistency verification of marker-less gait assessment system for stair walking

Ami Ogawa, Ayanori Yorozu, Akira Mita, Masaki Takahashi, Christos Georgoulas, Thomas Bock

Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) 9656 653 - 663 2016

Accepted, ISSN 0302-9743

© Springer International Publishing Switzerland 2016. The number of elderly people is drastically increasing. To support them, the gait information is under the spotlight since it has the relationship between the fall risk and dementia. Among other scenarios, a relatively higher level of ability is needed for the stair walking as it requires balancing and loading. Conventionally, 3D motion capture devices have been used to acquire the parameters of stair walking. However, it is difficult to acquire daily parameters as the equipment needs complicated preparation and body-worn markers. In this study, we propose a system which can acquire daily stair walking parameters using only depth data obtained by Kinect v2 without restraining by markers. We confirmed the accuracy of our proposed system compared with a 3D motion capture system.

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Recognition of human activities using depth images of Kinect for biofied building

Ami Ogawa, Akira Mita

Proceedings of SPIE - The International Society for Optical Engineering 9435 2015

Accepted, ISSN 0277-786X

© 2015 SPIE. These days, various functions in the living spaces are needed because of an aging society, promotion of energy conservation, and diversification of lifestyles. To meet this requirement, we propose "Biofied Building". The "Biofied Building" is the system learnt from living beings. The various information is accumulated in a database using small sensor agent robots as a key function of this system to control the living spaces. Among the various kinds of information about the living spaces, especially human activities can be triggers for lighting or air conditioning control. By doing so, customized space is possible. Human activities are divided into two groups, the activities consisting of single behavior and the activities consisting of multiple behaviors. For example, "standing up" or "sitting down" consists of a single behavior. These activities are accompanied by large motions. On the other hand "eating" consists of several behaviors, holding the chopsticks, catching the food, putting them in the mouth, and so on. These are continuous motions. Considering the characteristics of two types of human activities, we individually, use two methods, R transformation and variance. In this paper, we focus on the two different types of human activities, and propose the two methods of human activity recognition methods for construction of the database of living space for "Biofied Building". Finally, we compare the results of both methods.

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