研究者詳細 - 長谷川　泰久

論文 - 長谷川　泰久

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On-chip fabrication of cell-attached microstructures using photo-cross-linkable biodegradable hydrogel 査読有り国際共著

Takeuchi M., Kozuka T., Kim E., Ichikawa A., Hasegawa Y., Huang Q., Fukuda T.

Journal of Functional Biomaterials 11 巻 ( 1 ) 頁： 18 2020年3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：Journal of Functional Biomaterials

We developed a procedure for fabricating movable biological cell structures using biodegradable materials on a microfluidic chip. A photo-cross-linkable biodegradable hydrogel gelatin methacrylate (GelMA) was used to fabricate arbitrary microstructure shapes under a microscope using patterned ultraviolet light. The GelMA microstructures were movable inside the microfluidic channel after applying a hydrophobic coating material. The fabricated microstructures were self-assembled inside the microfluidic chip using our method of fluid forcing. The synthesis procedure of GelMA was optimized by changing the dialysis temperature, which kept the GelMA at a suitable pH for cell culture. RLC-18 rat liver cells (Riken BioResource Research Center, Tsukuba, Japan) were cultured inside the GelMA and on the GelMA microstructures to check cell growth. The cells were then stretched for 1 day in the cell culture and grew well on the GelMA microstructures. However, they did not grow well inside the GelMA microstructures. The GelMA microstructures were partially dissolved after 4 days of cell culture because of their biodegradability after the cells were placed on the microstructures. The results indicated that the proposed procedure used to fabricate cell structures using GelMA can be used as a building block to assemble three-dimensional tissue-like cell structures in vitro inside microfluidic devices.

DOI： 10.3390/jfb11010018

Construction of Hepatic-Lobule-Like 3-D Vascular Network in Cellular Structure by Manipulating Magnetic Fibers 査読有り

Kim E., Takeuchi M., Hasegawa A., Ichikawa A., Hasegawa Y., Huang Q., Fukuda T.

IEEE/ASME Transactions on Mechatronics 25 巻 ( 1 ) 頁： 477 - 486 2020年2月

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

Without perfusable vascular networks, 3-D tissues populated with cells cannot maintain a living condition. To construct 3-D tissues, a well-organized vascular network is required. In this article, a method for constructing a hepatic-lobule-like vascular network in a 3-D cellular structure by using magnetic fields is employed. To realize channel networks that mimic the hepatic lobule, steel rods and magnetic fibers were utilized as a sacrificial mold in fibrin gel. The steel rods and fibers were connected by magnetic fields using magnetic tweezers. In our previous work 'Construction of hepatic lobule-like vascular network by using magnetic fields' (Int. Conf. Robot. Autom., 2018, pp. 2688-2693), the tweezers were designed by 2-D simulation data. In addition, a 3-D cellular structure without a channel network was only cultured. New tweezers were designed based on 3-D simulation data to generate higher magnetic fields than the former tweezer. In addition, a tissue with the 3-D channel network was cultured for a week. To verify that the channel network can supply the nutrients to the cells in tissues, the viability of the cells located on the structure was analyzed. The cells close to the channel network show a higher cell viability than the cells far from the channel network.

DOI： 10.1109/TMECH.2019.2957494

Admittance control based robotic clinical gait training with physiological cost evaluation 査読有り

Itadera S., Nakanishi J., Hasegawa Y., Fukuda T., Tanimoto M., Kondo I.

Robotics and Autonomous Systems 123 巻頁： 103326 2020年1月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：Robotics and Autonomous Systems

In this paper, we investigate an effective control strategy for a cane-type assistive mobile robot toward clinical gait training. Assistive robots are expected to provide aid in order to reduce the burden of caregivers and physical therapists, e.g., in gait rehabilitation of elderly people. Our group has been developing a series of cane-type walking assistive robots named Intelligent Cane as a mobile hand-holding device based on admittance control to provide safe and efficient gait training. This paper explores a systematic design methodology of the admittance control model in order to provide suitable walking load during gait training. We first conduct a pilot experiment to investigate the relationship between the physiological cost of user's walking and the coefficients in the admittance control model of the cane robot. Then, we present a clinical gait training study conducted in a hospital to evaluate the feasibility in practical use of the proposed control strategy of our cane robot in gait rehabilitation. These experimental results suggest the effectiveness of the proposed gait rehabilitation strategy with our robot.

DOI： 10.1016/j.robot.2019.103326

Development of sense of self-location based on somatosensory feedback from finger tips for extra robotic thumb control 査読有り

Zhu Y., Ito T., Aoyama T., Hasegawa Y.

ROBOMECH Journal 6 巻 ( 1 ) 2019年12月

担当区分：最終著者記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：ROBOMECH Journal

Recently, wearable extra robotic limbs that aim to enhance the functionality and capability of human operators as extra arms or fingers have become an active research subject among robotics researchers. Improving the operability of the extra robotic limbs is required for the human operators, an approach for which is to induce robotic embodiment. In this paper, we focus on the update of sense of self-location which is the key aspect of embodiment and contributes to the body representation update, and we elucidate dominant factors which induce the embodiment of an extra robotic thumb (ERT). The experiments are conducted to compare the performance of the reaching task of the ERT under three separately given conditions, of which two are somatosensory feedbacks: (1) tactile and position feedback from the fingertips and (2) tactile and position feedback from the human face, and one is a non-somatosensory feedback: (3) auditory feedback. As a result, we confirmed that the somatosensory feedback from finger tips has a large contribution for the update of sense of self-location.

DOI： 10.1186/s40648-019-0135-0

A clinical pilot study on posture stabilization via light contact with cane-type companion robot 査読有り

Itadera S., Aoyama T., Hasegawa Y., Aimoto K., Kato K., Kondo I.

ROBOMECH Journal 6 巻 ( 1 ) 頁： 17 2019年12月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：ROBOMECH Journal

In this paper, toward robotic gait assistance, we investigate the feasibility of a cane-type assistive mobile robot accompanying the user autonomously through a clinical pilot experiment. As widely known, gait ability is important for all people to keep their quality of life. However, for people having weakened lower limbs such as elderly people, their postural sway during walking could be insuppressible and cause falling. To support the gait motion of elderly people, our group has been developing a series of hand-holding cane robots named Intelligent Cane. Such assistive robots are expected to remove barriers to the independent lives of elderly people. Recently, we have focused on the potential of a companion robot that follows the user ahead and can be touched or grasped for bracing whenever the user needs it. In order to demonstrate proof of our concept through an experiment with a motion capture system, we propose a user companion strategy that enables our cane robot to keep a constant relative distance between the robot and the user walking on a treadmill. We evaluate the accuracy of the user companion in an experiment where a user walks on a treadmill. Then, we conduct a clinical experiment with three healthy subjects walking on with the treadmill with our cane robot as a pilot study. Through the clinical experiment, we evaluate a postural stabilization effect of physical interaction with the robot and discuss the feasibility of our robotic gait assistance methodology.

DOI： 10.1186/s40648-019-0145-y

スマートアーム

長谷川泰久, 魚住大輔, 青山忠義, 中西淳

システム／制御／情報 63 巻 ( 10 ) 頁： 424 - 430 2019年10月

Predictive Optimization of Assistive Force in Admittance Control-Based Physical Interaction for Robotic Gait Assistance 査読有り国際共著

Itadera S., Dean-Leon E., Nakanishi J., Hasegawa Y., Cheng G.

IEEE Robotics and Automation Letters 4 巻 ( 4 ) 頁： 3609 - 3616 2019年10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

In this letter, we introduce our approach to walking assistance for elderly adults through predictive optimization of gait assistive force. We focus on providing supportive interaction force to the user during walking with a robotic assistive device with an admittance controlled mobile base. Appropriate physical human-robot interaction (pHRI) could be beneficial in reducing the risk associated with immobility such as disuse syndrome by encouraging physical activities with proper assistance. We propose an optimization algorithm based on a model predictive control approach in order to provide desirable assistive forces according to the estimated user's state during walking. Using a simplified human gait model with a linear inverted pendulum, we formulate the optimization of the assistive forces as a linear quadratic programming problem that can be suitable for real-time pHRI. Numerical simulations and experimental results demonstrate the feasibility of our gait support strategy in achieving appropriate compliant interactions during walking, fall prevention, and suitable positioning for user companion.

DOI： 10.1109/LRA.2019.2928770

Delays in perception and action for improving walk–run transition stability in bipedal gait 査読有り

Kobayashi T., Aoyama T., Sekiyama K., Hasegawa Y., Fukuda T.

Nonlinear Dynamics 97 巻 ( 2 ) 頁： 1685 - 1698 2019年7月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：Nonlinear Dynamics

This paper focuses on a transition motion between bipedal walking and running, whose characteristics have been revealed through numerous biological experiments. Although hysteresis in walk-to-run and run-to-walk transitions, the amount of which is proportional to the magnitude of acceleration/deceleration, is observed, it has not been elucidated yet. This is due to difficulty to conduct any biological experiments without the hysteresis in locomotion. From the viewpoint of nonlinear dynamics, the hysteresis is caused by dependency of the state history. Delays in perception and action for the walk–run transition can be assumed as the cause of the hysteresis. This paper therefore investigates i) whether the delays really cause the hysteresis in the walk–run transition, and ii) how they contribute to locomotion performance. To this end, in numerical simulations, we employ a controller for bipedal gait, named unified bipedal gait (UBG), which has capabilities of walking, running, and transitions between them like bipeds do. UBG is first optimized in pursue of biologically plausible controller with the same characteristics about the transition motion for reliable investigation. This optimized UBG reveals that the delays in perception and action actually cause the hysteresis with linearity of its amount and the magnitude of acceleration/deceleration. In addition, the delays play the key role of a bridge between latent representations of walking and running, thereby improving the success rate of the transition by nearly 40% from the case without the delays.

DOI： 10.1007/s11071-019-05097-0

Theoretical approach for designing the rehabilitation robot controller 査読有り国際共著

Okajima S., Alnajjar F.S., Costa Á., Asin-Prieto G., Pons J.L., Moreno J.C., Hasegawa Y., Shimoda S.

Advanced Robotics 33 巻 ( 14 ) 頁： 674 - 686 2019年7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：Advanced Robotics

Robot rehabilitation is now recognized as an important method for the efficient recovery. In European Project FP7 BioMot, we have discussed the potential of the robot rehabilitation and proposed the suitable process for it. In this paper, we describe the proposed rehabilitation process and create the theoretical basis for the robot rehabilitation through designing the control system and the patient model. To design the patient model, we describe the source of paralysis and motion controller separately and define the recovery function from the paralysis. In the theoretical analysis of the control system, we show that the robot motions are first adapted to the patient abnormal motions and gradually drive the patient motions to the better ones by the motion support. The singular perturbation analysis proves that the stabilities of the two different process, adaptation to the patient motions and the motion support to the better ones, as a slow motion subsystem and a fast motion subsystem, respectively. The simulation results show that the proposed control system can drive the patients to the better state depending on the patient conditions such as recovery speed and recovery potential. The proposed system can be tuned to fit to the variety of the real patient conditions when we apply it to the real applications.

DOI： 10.1080/01691864.2019.1633402

Medial part thickness of wearable device affecting running motion 査読有り

Naoki Kubota and Yasuhisa Hasegawa

ROBOMECH Journal 6 巻 ( 1 ) 2019年7月

Operational learning with sensory feedback for controlling a robotic thumb using the posterior auricular muscle 査読有り

Aoyama T., Shikida H., Schatz R., Hasegawa Y.

Advanced Robotics 33 巻 ( 5 ) 頁： 243 - 253 2019年3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：Advanced Robotics

Extra robotic limbs in a robotic system that are designed to augment and expand human abilities have received attention in the field of wearable robotics. We aim to develop a robotic system that is controlled by body parts that are not used on a daily basis in order to augment and expand human abilities. This paper presents operational learning experiments for manipulating a robotic thumb using the posterior auricular muscle, a body part that is not used in everyday life. In these experiments, reaching motions were executed using sensory feedback in the robotic thumb through a device that continuously displays its position. The experimental results indicate the proposed operational learning experiments improve the ability to contract the posterior auricular muscles. In addition, the results indicate the operability of a robotic thumb could be improved by acquiring internal models through repetitive operational learning.

DOI： 10.1080/01691864.2019.1566090

Modification of body schema by use of extra robotic thumb 査読有り

Segura Meraz N., Sobajima M., Aoyama T., Hasegawa Y.

ROBOMECH Journal 5 巻 ( 1 ) 2018年12月

担当区分：最終著者記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：ROBOMECH Journal

In recent years, there has been great interest in the possibility of using artificial limbs as an extension of the human body as well as replacement of lost limbs. In this paper, we develop a sixth finger system as an extension of the human body. We then investigate how an extra robotic thumb, that works as a sixth finger and gives somatosensory feedback to the user, modifies the body schema, and also affecting the self-perception of existing limbs. The sixth robotic finger is controlled with the thumb of the opposite hand, and contact information is conveyed via electrostimulation to the tip of the thumb controlling the movement. We conducted reaching task experiments with and without visual information to evaluate the level of embodiment of the sixth robotic finger and the modification of the self-perception of the finger controlling the system. The experimental results indicate that not only the sixth finger is incorporated into the body schema of the user, but also the body schema of the controlling finger is modified; ability of the brain to adapt to different scenarios and geometries of the body is also implied.

DOI： 10.1186/s40648-018-0100-3

Virtual-dynamics-based reference gait speed generator for limit-cycle-based bipedal gait 査読有り

Kobayashi T., Sekiyama K., Hasegawa Y., Aoyama T., Fukuda T.

ROBOMECH Journal 5 巻 ( 1 ) 2018年12月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：ROBOMECH Journal

This paper addresses a reference gait speed generator for limit-cycle-based bipedal gait of humanoid robots in order to achieve secure and efficient acceleration and deceleration without falling down at respective gait speeds. The reference gait speed generator is hard to be developed by analytical approaches due to the necessity of barren work for identifying the respective basins of attraction. We challenge this issue by designing virtual dynamics among a robot, a virtual leader point, and a goal, and adapting it according to a falling risk of the robot. The virtual dynamics, which has settling and acceleration times as design parameters, gives the reference speeds derived from states of the robot and the leader point to a gait speeds controller. In the dynamics, the robot’s mass is optimized virtually to maximize efficiency while ensuring stability stochastically by using a selection algorithm for locomotion. Even when there were obstacles or an up slope in traveling courses of simulations, the robot achieved the autonomous traveling from the start to the goal securely. Specific resistance was also kept small in comparison with local-stability-based walking. The proposed method makes the limit-cycle-based bipedal gait more practical and contributes toward replacing the major method that ensures stability of every step.

DOI： 10.1186/s40648-018-0115-9

Electric Stimulation based Weight Discrimination for Paraplegic Wearing Exoskeleton 国際誌

Li M., Wang X., Aoyama T., Hasegawa Y.

2018 International Conference on Intelligence and Safety for Robotics, ISR 2018 頁： 261 - 266 2018年11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：2018 International Conference on Intelligence and Safety for Robotics, ISR 2018

This paper proposes an electrical stimulation system to provide a lower limb motion state for paraplegic patients wearing an exoskeleton. The system consists of a glove-type exoskeleton controller and an electric stimulation device. In addition, a mechanical leg, which simulates a paraplegic's lower limb wearing an exoskeleton, was developed to conduct the preliminary experiment. The operator using his finger voluntarily controls the movement of the mechanical leg through the glove-type controller. Meanwhile, he receives electrical stimulation feedback that represents the output torque of the mechanical leg. In this manner, the system makes a connection between finger's motion and electrical stimulation. The operator could predict the feedback when he controls the mechanical leg. Finally, weight discrimination experiments were implemented to evaluate the accuracy of the electrical stimulation system. The subjects control the mechanical leg and receive electrical stimulation with different weight loading on the mechanical leg. The experimental results indicate that: 1) The dynamic of the mechanical leg is integrated into the body scheme of the subjects after training. 2) The subjects are capable of distinguishing a 17 percent change of weight loading at the minimum under the feedback of electric stimulation.

DOI： 10.1109/IISR.2018.8535936

Precise foot positioning of walking robot for paraplegic patient wearing exoskeleton by using electrical stimulation feedback 査読有り

Li M., Yuan Z., Aoyama T., Hasegawa Y.

Journal of Mechanisms and Robotics 10 巻 ( 4 ) 2018年8月

担当区分：最終著者記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Mechanisms and Robotics

The research and development of powered exoskeletons is expected to support the walking of paraplegic patients. At the current stage, exoskeletons do not allow patients to voluntarily control their gait, nor do they provide sensory feedback to compensate for the loss of lower-body sensation. This paper proposes a wearable walking control interface to achieve voluntary gait control, and an electrical stimulation method to inform the patients about their foot position for voluntary gait control. In this study, a walking robot that simulated a paraplegic patient wearing an exoskeleton was used to investigate the performance of the proposed interface and stimulation method. We confirmed that, by using the interface, the subjects were able to control the robot gait for a distance of 3 m. Moreover, the accuracy of the electrical stimulation feedback was confirmed to approximate the visual feedback achieved through the human eyes. The experimental results revealed that the proposed interface and electrical stimulation feedback could be applied to a walking support system for patients with complete paraplegia.

DOI： 10.1115/1.4040354

Generation of Human-Like Movement from Symbolized Information 査読有り国際共著

Okajima Shotaro, Tournier Maxime, Ainajjar Fady S., Hayashibe Mitsuhiro, Hasegawa Yasuhisa, Shimoda Shingo

FRONTIERS IN NEUROROBOTICS 12 巻 2018年7月

Nanorobotic Manipulation of Thin-film Graphite Sheet for 3D Cubic Structures 査読有り国際共著

Takafumi Fujiwara, Masahiro Nakajima, Yasuhisa Hasegawa, Toshio Fukuda, Huang Qiang,

Nanomedicine and Nanoscience Research 2018 ( 2 ) 頁： pp.1-9 2018年7月

Unified bipedal gait for autonomous transition between walking and running in pursuit of energy minimization 査読有り

Kobayashi T., Sekiyama K., Hasegawa Y., Aoyama T., Fukuda T.

Robotics and Autonomous Systems 103 巻頁： 27 - 41 2018年5月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：Robotics and Autonomous Systems

This paper addresses “unified bipedal gait” control, which autonomously selects the energy-minimized gait from walking and running at any feasible gait speeds. Humans select walking/running at low/high speed in pursuit of energy minimization and transition between them naturally. Despite the quite different behaviors of walking and running, human gaits share an inherent controller. The unified bipedal gait uses the inherent controller, which implements passive dynamic autonomous control (PDAC) based on a damping and spring-loaded inverted pendulum (D-SLIP) model. Although this D-SLIP could cause chaotic motions, compliance in the D-SLIP dynamics switches behaviors between walking and running, that is, low/high compliant legs for walking/running. This property is employed by the virtual holonomic constraint of the PDAC to extract the required characteristics of walking/running from the D-SLIP dynamics while restraining the chaotic motions for asymptotic stability. As a result, the unified bipedal gait bifurcates to walking and running via autonomous transition to minimize energy cost at any feasible gait speeds.

DOI： 10.1016/j.robot.2018.02.005

Wearable Robotics for Motion Assistance and Rehabilitation [TC Spotlight] Open Access

Mohammed S., Moreno J., Sugar T., Hasegawa Y., Vitiello N., Wang Q., Walsh C.

IEEE Robotics and Automation Magazine 25 巻 ( 1 ) 2018年3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 Magazine

The IEEE Robotics and Automation Society (RAS) Technical Committee (TC) on Wearable Robotics was approved during the IEEE RAS Technical Activities Board meeting that was held 15 May 2016 in Stockholm, Sweden, along with the IEEE International Conference on Robotics and Automation (ICRA) 2016. The TC maintained a high level of activities, including the organization of a series of scientific events such as conferences, summer schools, and special sessions/workshops in major RAS and non-RAS conferences, as well as leading special issues in prestigious Institute for Scientific Information journals. The TC provided a platform to promote international initiatives, innovative and industrial solutions for the assistance of frail people, which would provide an excellent opportunity to share information and technology transfer between experts from different fields such as medical, social, caregiving, and industry.

DOI： 10.1109/MRA.2017.2787222

In vitro mimicking the morphology of hepatic lobule tissue based on Ca-alginate cell sheets 査読有り国際共著

Liu Z., Lu M., Takeuchi M., Yue T., Hasegawa Y., Huang Q., Fukuda T.

Biomedical Materials (Bristol) 13 巻 ( 3 ) 2018年2月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：Biomedical Materials (Bristol)

Artificial cell sheets are commonly utilized as buiding blocks for tissue engineering. We propose a novel approach in the fabrication of Ca-alginate gel sheets, embedded with liver cells (RLC-18) in order to mimic liver lobule tissue. Ca-alginate sheets with hepatic lobule-shaped patterns were deposited onto a micro-electrode device using electrodeposition. Viability of embedded cells was ensured to exceed 80%. Cell morphology and biofunctionality were monitored during the one-week culture period and results compared with those of traditional 2D culture. In addition, we detached cell sheets from the electrode substrate and stacked them into a 3D multi-layered structure to mimic the morphology of liver lobule tissue.

DOI： 10.1088/1748-605X/aaa4c4

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