研究者詳細 - 長谷川　泰久

Development of a compliant gripper for safe robot-assisted trouser dressing-undressing 査読有り国際誌

Jayant Unde, Takumi Inden, Yuki Wakayama, Jacinto Colan, Yaonan Zhu, Tadayoshi Aoyama, Yasuhisa Hasegawa

Advanced Robotics 頁： 1 - 17 2024年7月

Variable step sizes for iterative Jacobian-based inverse kinematics of robotic manipulators 査読有り

JACINTO COLAN, ANA DAVILA, AND YASUHISA HASEGAWA

IEEE Access 4 巻 ( 2016 ) 頁： 87909 - 87922 2024年6月

Comparison of fine-tuning strategies for transfer learning in medical image classification Open Access

Davila A., Colan J., Hasegawa Y.

Image and Vision Computing 146 巻頁： 105012 2024年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Image and Vision Computing

In the context of medical imaging and machine learning, one of the most pressing challenges is the effective adaptation of pre-trained models to specialized medical contexts. Despite the availability of advanced pre-trained models, their direct application to the highly specialized and diverse field of medical imaging often falls short due to the unique characteristics of medical data. This study provides a comprehensive analysis on the performance of various fine-tuning methods applied to pre-trained models across a spectrum of medical imaging domains, including X-ray, MRI, Histology, Dermoscopy, and Endoscopic surgery. We evaluated eight fine-tuning strategies, including standard techniques such as fine-tuning all layers or fine-tuning only the classifier layers, alongside methods such as gradually unfreezing layers, regularization based fine-tuning and adaptive learning rates. We selected three well-established CNN architectures (ResNet-50, DenseNet-121, and VGG-19) to cover a range of learning and feature extraction scenarios. Although our results indicate that the efficacy of these fine-tuning methods significantly varies depending on both the architecture and the medical imaging type, strategies such as combining Linear Probing with Full Fine-tuning resulted in notable improvements in over 50% of the evaluated cases, demonstrating general effectiveness across medical domains. Moreover, Auto-RGN, which dynamically adjusts learning rates, led to performance enhancements of up to 11% for specific modalities. Additionally, the DenseNet architecture showed more pronounced benefits from alternative fine-tuning approaches compared to traditional full fine-tuning. This work not only provides valuable insights for optimizing pre-trained models in medical image analysis but also suggests the potential for future research into more advanced architectures and fine-tuning methods.

DOI： 10.1016/j.imavis.2024.105012

Passive Lower Limb Exoskeleton for Kneeling and Postural Transition Assistance With Expanded Support Polygon Open Access

Real-time inverse kinematics for robotic manipulation under remote center-of-motion constraint using memetic evolution 査読有り国際誌

Ana Davila, Jacinto Colan, Yasuhisa Hasegawa

Journal of Computational Design and Engineering 11 巻 ( 3 ) 頁： 248-264 2024年5月

Multimodal semi-supervised learning for online recognition of multi-granularity surgical workflows 査読有り国際誌

Yutaro Yamada, Jacinto Colan, Ana Davila, Yasuhisa Hasegawa

International Journal of Computer Assisted Radiology and Surgery 19 巻 ( 6 ) 頁： 1075 - 1083 2024年4月

Sugiura S., Zhu Y., Huang J., Hasegawa Y.

IEEE ASME Transactions on Mechatronics 29 巻 ( 2 ) 頁： 1193 - 1204 2024年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：IEEE ASME Transactions on Mechatronics

Robotic exoskeletons, which assist in stand-to-kneel and kneel-to-stand (STK-KTS) movements and static kneeling postures are in great demand in the nursing field. This movement involves continuous adjustment of the center of gravity without a sufficient support polygon, which enhances the required joint effort of the ankle and knee. This study proposes a novel passive lower limb exoskeleton to support the movement. The exoskeleton was attached to the right leg and comprised a gas spring. The design followed an assistive strategy of the expanded support polygon. During the STK-KTS, the gas spring provided extra contact with the ground, thereby expanding the support polygon to increase motion stability and propping the knee to provide torque to the leg. The effectiveness of the gas spring was analyzed using a Lagrange dynamics-based simulation. Moreover, it was confirmed that the support polygon was expanded due to the proposed exoskeleton in real-world experiments. Further, experiments with seven healthy subjects showed that the exoskeleton reduced the time-integrated myoelectric potentials of the legs during STK-KTS (13.6%) and static posture (37.9%). These results imply that the proposed exoskeleton has the potential to reduce physical loads and provide a comfortable working environment for nursing workers.

DOI： 10.1109/TMECH.2023.3294255

Latent regression based model predictive control for tissue triangulation 査読有り

Songtao Liu, Jacinto Colan, Yaonan Zhu, Taisuke Kobayashi, Kazunari Misawa, Masaru Takeuchi, Yasuhisa Hasegawa

Advanced Robotics 38 巻 ( 5 ) 頁： 283 - 306 2024年3月

Real-Time Spatiotemporal Assistance for Micromanipulation Using Imitation Learning 査読有り国際誌

Ryoya Mori, Tadayoshi Aoyama, Taisuke Kobayashi, Kazuya Sakamoto, Masaru Takeuchi, Yasuhisa Hasegawa

IEEE Robotics and Automation Letters 9 巻 ( 4 ) 頁： 3506 - 3513 2024年2月

Real-time motion force-feedback system with predictive-vision for improving motor accuracy 査読有り国際誌

Ryo Matsui, Tadayoshi Aoyama, Kenji Kato, Yasuhisa Hasegawa

Scientific Reports 14 巻 ( 1 ) 頁： 2168 2024年1月

Intuitive Cell Manipulation Microscope System with Haptic Device for Intracytoplasmic Sperm Injection Simplification 査読有り

Kazuya Sakamoto, Tadayoshi Aoyama, Masaru Takeuchi, Yasuhisa Hasegawa

Sensors 24 巻 ( 2 ) 頁： 711 2024年1月

Variable Grounding Flexible Limb Tracking Center of Gravity for Sit-to-Stand Transfer Assistance 国際誌 Open Access

Sugiura S., Unde J., Zhu Y., Hasegawa Y.

IEEE Robotics and Automation Letters 9 巻 ( 1 ) 頁： 175 - 182 2024年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：IEEE Robotics and Automation Letters

Wearable robotic limbs support sit-to-stand (STS) transfer with increased stability while maintaining a compact size, as well as providing body weight support. This paper proposes a new robotic limb, Variable Grounding Flexible Limb (VGFL). The VGFL achieved a novel strategy in which its grounding point tracks the forward shift of the wearer's center of gravity (CoG) during STS. Since the strategy keeps the distance between the grounding point and the CoG close, an upward force can efficiently work for the STS assistance. To implement the strategy, this paper utilized the High-Strength and Flexible Mechanism (HSFM). The HSFM can change its grounding point while being capable of lifting body weight with one motor. Owing to these unique characteristics, the VGFL can realize the strategy without multiple actuators and complex controllers. Furthermore, real-world experiments confirmed that the grounding point of the VGFL accurately tracked the forward shift of the CoG during the STS assistance. Moreover, experiments conducted with three healthy subjects showed that the VGFL reduced the surface myoelectricity of the lower limbs during STS transfer. The VGFL could demonstrate high support performance in STS with the CoG tracking strategy.

DOI： 10.1109/LRA.2023.3328449

Intuitive Cell Manipulation Microscope System with Haptic Device for Intracytoplasmic Sperm Injection Simplification Open Access

Sakamoto K., Aoyama T., Takeuchi M., Hasegawa Y.

Sensors 24 巻 ( 2 ) 頁： 711 - 711 2024年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Sensors

In recent years, the demand for effective intracytoplasmic sperm injection (ICSI) for the treatment of male infertility has increased. The ICSI operation is complicated as it involves delicate organs and requires a high level of skill. Several cell manipulation systems that do not require such skills have been proposed; notably, several automated methods are available for cell rotation. However, these methods are unfeasible for the delicate ICSI medical procedure because of safety issues. Thus, this study proposes a microscopic system that enables intuitive micropipette manipulation using a haptic device that safely and efficiently performs the entire ICSI procedure. The proposed system switches between field-of-view expansion and three-dimensional image presentation to present images according to the operational stage. In addition, the system enables intuitive pipette manipulation using a haptic device. Experiments were conducted on microbeads instead of oocytes. The results confirmed that the time required for the experimental task was improved by 52.6%, and the injection error was improved by 75.3% compared to those observed in the conventional system.

DOI： 10.3390/s24020711

Assistive System for Microinjection by Presenting Cell Deformation as Surface Tactile Sensation Open Access

Saito S., Aoyama T., Funabora Y., Takeuchi M., Hasegawa Y.

IEEE Access 12 巻頁： 3874 - 3880 2024年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：IEEE Access

Microinjection technology has been widely applied in various fields, including biology, medicine, and intracytoplasmic sperm injection (ICSI). In a typical ICSI environment, all tasks, such as determining the degree of extension, adjusting the depth of focus, finding polar bodies, and manipulating cells, rely only on visual information; therefore, the person performing ICSI should have particular skills. Consequently, ICSI is generally performed by embryologists specialized in embryo handling. However, with the recent growth in global demand for ICSI, there is a shortage of embryologists and lack of experience among embryologists, and a simple injection system that does not rely on skilled embryologists is required. In this study, we propose a micromanipulation interface that provides a surface tactile sensation with a fabric actuator based on the real-time image measurement of the degree of cell deformation to simplify our understanding of the cell state. The effectiveness of the proposed interface is verified through cell-puncture experiments conducted by novices and one expert.

DOI： 10.1109/ACCESS.2023.3349169

Design, Modeling, and Experimental Verification of Passively Adaptable Roller Gripper for Separating Stacked Fabric Open Access

その他リンク： https://ieeexplore.ieee.org/abstract/document/10379610

Unde J., Colan J., Hasegawa Y.

IEEE Robotics and Automation Letters 9 巻 ( 11 ) 頁： 9335 - 9342 2024年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：IEEE Robotics and Automation Letters

This letter presents a novel approach to fabric manipulation through the development and optimization of a single-actuator-driven roller gripper. Focused on addressing the challenges inherent in handling fabrics with diverse thicknesses and materials, our gripper employs a passive adaptable mechanism driven by springs, enabling effective manipulation of fabrics ranging from 0.1 mm to 2.25 mm in thickness. We analyze gripper-fabric interaction forces to identify the parameters that influence successful grasping. We then optimize the gripper's normal forces and the roller's tangential force using the proposed model. Systematic evaluations demonstrated the gripper's capability to separate individual layers from fabric stacks, achieving a 94.9% success rate across multiple fabric types. Overall, this research offers a compact, cost-effective solution with broad applicability in diverse industrial automation contexts, providing valuable insights for advancing robotic fabric handling systems.

DOI： 10.1109/LRA.2024.3461550

Wearable Fabric Actuator Inducing Shoulder Movements for Directional Guidance of Hand Movements

Yokoe K., Aoyama T., Funabora Y., Takeuchi M., Hasegawa Y.

Proceedings of the 2024 IEEE International Conference on Cyborg and Bionic Systems, CBS 2024 頁： 255 - 258 2024年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：Proceedings of the 2024 IEEE International Conference on Cyborg and Bionic Systems, CBS 2024

In recent years, there has been an increasing focus on teleoperation of robots via immersive environments. These systems require haptic sensation to the hand for intuitive teleoperation. However, most methods for providing haptic sensation to the hand may interfere with hand position acquisition by vision and other devices. Thus, there is a need for a method that can coexist with the acquisition of hand information. This paper presents a method for guiding directions of hand movements in immersive environments using McKibben-based haptic sensations, which can coexist with the acquisition of hand information. The proposed system employs a wearable fabric actuator consisting of four McKibben-type artificial muscles that induce internal rotation, external rotation, internal abduction, and external abduction of the shoulder. By combining these four haptic sensations, the proposed system can guide the direction of hand movements without interfering with hand information acquisition by other devices. An algorithm is implemented to effectively combine the four haptic sensations based on the target guiding direction. We evaluated the accuracy and speed of the proposed system through a participant experiment.

DOI： 10.1109/CBS61689.2024.10860490

RNN-Based Visual Guidance for Enhanced Sense of Agency in Teleoperation With Time-Varying Delays Open Access

Morita T., Armleder S., Zhu Y., Iino H., Aoyama T., Cheng G., Hasegawa Y.

IEEE Robotics and Automation Letters 9 巻 ( 12 ) 頁： 11537 - 11544 2024年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：IEEE Robotics and Automation Letters

Intuitive teleoperation enables operators to embody remote robots, providing the sensation that the robot is part of their own body during control. The sense of agency (SoA), i.e., the feeling of controlling the robot, contributes to enhanced motivation and embodiment during teleoperation. However, the SoA can be diminished by time-varying communication delays associated with teleoperation. We propose a visual guidance system to assist operations while maintaining a high SoA when teleoperating robots with time-varying delays, thereby improving positioning accuracy. In the proposed system, a recurrent neural network (RNN) model, trained on the pouring tasks of skilled operators, predicts the input position 500 ms ahead of the input from the novice operator and visually presents it in real-time as the end-effector target position. Experiments with time-varying delays confirmed that the proposed method provides a visual representation of the target position interpolated in time and space from the real-time input of the operator, guiding the operator to align with the trajectory of the skilled operator. The proposed method significantly improves task performance even under time-varying delays while maintaining a high SoA compared with other conditions. Applying the prediction system developed in this study to human-robot collaborative control may enable interventions that maintain the SoA.

DOI： 10.1109/LRA.2024.3495591

Elbow Angle Guidance System Based on Surface Haptic Sensations Elicited by Lightweight Wearable Fabric Actuator

Yokoe K., Aoyama T., Funabora Y., Takeuchi M., Hasegawa Y.

IEEE/ASME International Conference on Advanced Intelligent Mechatronics, AIM 頁： 1447 - 1454 2024年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：IEEE/ASME International Conference on Advanced Intelligent Mechatronics, AIM

The demand for wearable haptic devices has rapidly increased for various applications. However, many haptic devices interfere with the wearer's activities and movements. In addition, several haptic devices fail to elicit intuitive haptic sensations by adjusting to the natural posture of the wearer. To address these issues, we propose an elbow angle guidance system using a lightweight wearable fabric actuator. The proposed actuator is made of fabric and has two McKibben-type artificial muscles attached to it, rendering it extremely lightweight and facilitating the delivery of surface haptic sensations to intuitively induce elbow extension and flexion. The surface haptic sensation elicited by the fabric actuator is adjusted to natural body movements without interfering with the wearer's movements. Moreover, the proposed system measures and guides the elbow angle by changing the intensity of the surface haptic sensation delivered to users in real time. The accuracy of the proposed system is demonstrated through experiments involving human participants.

DOI： 10.1109/AIM55361.2024.10637238

Development of a compliant gripper for safe robot-assisted trouser dressing-undressing

Unde J., Inden T., Wakayama Y., Colan J., Zhu Y., Aoyama T., Hasegawa Y.

Advanced Robotics 38 巻 ( 19-20 ) 頁： 1424 - 1440 2024年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Advanced Robotics

In recent years, many countries, including Japan, have rapidly aging populations, making the preservation of seniors' quality of life a significant concern. For elderly people with impaired physical abilities, support for toileting is one of the most important issues. This paper details the design, development, experimental assessment, and potential application of the gripper system, with a focus on the unique requirements and obstacles involved in aiding elderly or hemiplegic individuals in dressing and undressing trousers. The gripper we propose seeks to find the right balance between compliance and grasping forces, ensuring precise manipulation while maintaining a safe and compliant interaction with the users. The gripper's integration into a custom-built robotic manipulator system provides a comprehensive solution for assisting hemiplegic individuals in their dressing and undressing tasks. Experimental evaluations and comparisons with existing studies demonstrate the gripper's ability to successfully assist in both dressing and dressing of trousers in confined spaces with a high success rate. This research contributes to the advancement of assistive robotics, empowering elderly, and physically impaired individuals to maintain their independence and improve their quality of life.

DOI： 10.1080/01691864.2024.2376024

A Neurostimulator with Wireless Bidirectional Communication for Controlling Muscle Contraction Force using Electromyography

Takeuchi M., Niimi T., Tokutake K., Kurimoto S., Aoyama T., Hirata H., Hasegawa Y.

IEEE International Conference on Nano Molecular Medicine and Engineering Nanomed 頁： 104 - 107 2024年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：IEEE International Conference on Nano Molecular Medicine and Engineering Nanomed

This paper presents a wirelessly powered neurostimulator with wireless bidirectional communication to control muscle contraction. The transmitter device sends the information about neural stimulation to the receiver device, while the receiver device sends the measured electromyography (EMG) inside a body to the transmitter device. Based on the measured EMG, the neural stimulation was adjusted to achieve the target EMG. The muscle contraction force can be controlled by EMG control. The EMG estimation error by the developed device was less than 2% when the muscle activity was active. This study can contribute to force control of paralyzed patients' bodies.

DOI： 10.1109/NANOMED64244.2024.10946046