Omnidirectional Walker Research Articles

Tracking Control for a Rehabilitative Training Walker Considering Human-Robot Interaction

A new extended state observer combined with a Backstepping tracking control method were proposed in this paper for the omnidirectional rehabilitative training walker. The aim of this study is to obtain a stable tracking controller, and it considered the interaction forces of the user and walker to ensure that the omnidirectional walker can track accurately specified trajectory. The extended state observer was designed to estimate the unknown interaction forces of user and the walker using output position and speed states. Further, a Backstepping controller based on the observed value was constructed to resist the adverse effects of interaction forces. The asymptotic stability of the trajectory tracking error, the velocity tracking error and the state observation error were guaranteed. Through programming, simulation results show the effectiveness of the proposed design method.

Nonfragile predictive control for an omnidirectional rehabilitative training walker with constraints on the tracking errors of position and velocity

SummaryHere, we propose a novel nonfragile predictive control method for an omnidirectional rehabilitative training walker. The aim of the study was to design a tracking controller that includes simultaneous constraints on the tracking errors in the position and velocity in order to guarantee safe system states for the omnidirectional walker. The nonfragile controller uses incremental control to solve the optimal quadratic program problem. The exponential stability of the system is guaranteed by constructing constraints on the trajectory‐tracking error and the velocity‐tracking error. Simulation and experimental testing were conducted to confirm the effectiveness of the proposed method and verify that it can provide safe positions and velocities when applied to control the motion of an omnidirectional walker.

Interaction Forces Identification Modeling and Tracking Control for Rehabilitative Training Walker

In this study, we propose a model and an adaptive backstepping tracking control method for omnidirectional rehabilitative training walker. The aim of the study is to design a stable tracking controller that can guarantee accurate tracking motion of the omnidirectional walker considering the interaction forces of the user and walker. A novel fuzzy model identification method was proposed to describe the interaction forces by using the reduced values of tracking performance. Further, an adaptive backstepping controller was developed to compensate the interaction forces on the basis of the identified model and adapt the change of user’s mass. The asymptotic stability of the trajectory tracking error and the velocity tracking error were guaranteed. As an application, simulation and experiment results were provided to illustrate the effectiveness of the proposed design procedures.

904 全方向移動型歩行訓練機の走行制御(ロボティクス・メカトロニクスIV)

904 全方向移動型歩行訓練機の走行制御(ロボティクス・メカトロニクスIV)

Directional control of an omnidirectional walking support walker: adaptation to individual differences with fuzzy learning

We are developing a method to recognize a user’s directional intention to control an omnidirectional walker (ODW) according to the force interaction between the ODW and the user. Since the characteristics in the force interaction are different among persons especially for those with walking difficulty, a fuzzy learning method is developed in this study to adapt to the individual difference in forearm pressures in order to improve the usability of the method. The experiment results show that fuzzy learning can significantly improve the accuracy of recognition by updating the fuzzy rules according to the characteristics in the force interaction.

813 全方向移動型歩行訓練機を用いた歩行訓練中の下肢運動の違いによる加速度変化の差異(ロボティクス・メカトロニクスIII)

813 全方向移動型歩行訓練機を用いた歩行訓練中の下肢運動の違いによる加速度変化の差異(ロボティクス・メカトロニクスIII)

519 デジタル加速度制御法を用いた全方向移動型歩行訓練機の経路追従(機素潤滑設計III)

519 デジタル加速度制御法を用いた全方向移動型歩行訓練機の経路追従(機素潤滑設計III)

322 全方向移動型歩行訓練機の走行制御

In ageing society, more and more people suffer from walking disable due to illness or accident. In order to recover they need to do walking rehabilitation. An omni-directional walker (ODW) is being developed for both walking rehabilitation and walking support for people with walking disabilities. Walking program are stored in the ODW, so that walking rehabilitation can be executed without physical therapist. However, the ODW cannot accurately follow a training path planned by a physical therapist for walking rehabilitation due to the center-of-gravity shifts and load changes caused by users. In previous studies, a gravity center model was derived, and a adaptive control method was developed to consider the center-of-gravity shifts and load changes. In this paper, to accurately describe the characteristic of the ODW, a new center model is derived considering center-of-gravity shifts and load changes. An improved adaptive control strategy is proposed. Finally, a circle path is simulated with or without center-of-gravity shifts and load changes. Simulation results show that the proposed method is effectiveness to improve the path tracking accurate.

A novel direction control method for walking support with an omnidirectional walker

Safe and convenient walking support machines are strongly desired for the people suffering from walking disabilities. We have developed an omnidirectional walker (ODW) for walking support. In walking support, it is necessary to control the ODW following the user's directional intention. In this paper, a novel interface is proposed to recognise the user's directional intention according to the forearm pressures. The forearm pressures exerted to the ODW by the user with wrists and elbows are measured by four force sensors embedded in the ODW's armrest. The relationship between the forearm pressure and the directional intention was extracted as fuzzy rules and an algorithm was proposed for directional intention identification based on distance–type fuzzy reasoning method. We conducted a path tracking experiment with the proposed method. The results show that the algorithm is applicable to control the ODW in walking support.

2P1-G01 歩行補助機走行制御(福祉ロボティクス・メカトロニクス(1))

Walking is a fundamental ability necessary for everyday life. In this paper, an omni-directional walker (ODW), which can support people with walking disabilities to perform indoor walking and rehabilitation, is introduced. To control the ODW's movement toward the direction in which the user intends to go during walking support, an adaptive control method is proposed. We simulate the walker's movement along the path generated based on the results of directional intention identification. Simulation results show the ODW can accurately following the user's intention direction, which shows the feasibility and effectiveness of the proposed scheme.

Adaptive control strategy with parameter optimisation for omni-directional walker

In order to support people with walking disabilities to perform walking rehabilitation, an omni-directional walker (ODW) has been developed. Walking training programmes are stored in the walker so that rehabilitation can be carried out without a physical therapist. During walking training the forces imposed by the user’s arms to the armrest of the ODW decreased the path tracking accuracy. In a previous study, to address the issue, an adaptive control algorithm was developed to deal with the centre of gravity shift and the load changes caused by the users. However, the control parameters in the non-linear adaptive control law were manually adjusted. In this paper, an adaptive control strategy with automatic parameter adjustment by genetic algorithm is proposed. Simulations are presented to show the feasibility and effectiveness of the proposed scheme.

112 歩行訓練機の制御パラメータの自動調整(情報・知能・精密機器II)

112 歩行訓練機の制御パラメータの自動調整(情報・知能・精密機器II)

Directional Intention Identification for Running Control of an Omnidirectional Walker

Walking is a vital exercise for health promotion and a fundamental ability necessary for everyday life. In previous work, we developed an OmniDirectional Walker (ODW) for walking rehabilitation and walking support. In walking support, it is necessary for the ODW to know the direction the user intends to go based on user manipulation. Actual directional intent must, however, be identified from physical manipulation because a user’s directional intent and physical manipulation are not always mutually consistent. In this paper, a novel interface is proposed to recognize a user’s directional intention according to the forearm pressures exerted to the ODW by the user with wrists and elbows. The forearm pressures are measured by 4 sensors embedded in the ODW’s armrest. The relationship between forearm pressure and directional intention was extracted as fuzzy rules and an algorithm was proposed for directional intention identification based on distance-type fuzzy reasoning method. The effectiveness of the algorithm was verified by experimental reasoning results demonstrated to be consistent with intended directions.

Special Issue on Human Symbiotic System

With opportunities for human beings to coexist with artificial agents and autonomous robots are increasing, high-level interactive communication between them is increasingly needed. These human symbiotic systems are used for research on basic intelligent interaction design principles and methods and bidirectional communication based on effective collaboration and symbiosis between human beings and robots, agents, and computers, also known as artifacts. The research society on gHuman Symbiotic System (HSS)h was implemented by the Japan Society for Fuzzy Theory and Intelligent Informatics (SOFT) in 2007. The HSS encourages academic and industrial discussion of research on Human-Agent Interaction (HAI), Human-Robot Interaction (HRI), and Human-Computer Interaction (HCI). The objective of this special issue is to activate and expand top-quality research of HSS theory and applications. Reflecting the fact that this research covers a wide range of topics, we invited researchers from fields including intelligent robotics, human-machine interfaces, and Kansei engineering to contribute. This issue thus provides much of the latest practical research on HSS, introduced by core members of the research society. Of the 22 papers received, 14 were accepted after input from two reviewers each. The first paper, by Y. Tamura et al., presents an attentive deskwork support system that delivers required items objects to deskworkers. The second, by H. Masuta et al., discusses an integrated perceptual system for intelligent service robots. The third, by S. Akiguchi, develops an automatic pattern generation system based on user impression. The fourth, by Y. Jiang et al., deals with a novel interface recognizing directional user intent based on forearm pressure exerted by the user of an omnidirectional walker. The fifth paper, by K. Terabayashi et al., investigates effects of preoperation on the experience of hands of different sizes by classifying preoperations based on the hand/object relationship. The sixth, by Y. Tamura et al., proposes segmenting a performerfs body imitating behavior observed based on a system from which values are obtained by reinforcement learning. The seventh, by D. Katagami et al., discusses group-adaptive behavior based on utterance contents and social standing of a robot. The eighth, by H. Yamaguchi et al., presents a system for using discounted utterances in spontaneous conversations applying text-mining technology. The ninth paper, by A. Otaki et al., focuses on the development of human negotiation skill through interaction between human players and computer agents in bargaining games. The tenth, by D. Katagami et al., is also related to human negotiation skill implementing human gestures in negotiation scenarios for three negotiation agents. The eleventh, by R. Taki et al., realizes interactive emotion communication - bidirectional communication based on emotional behavior between human beings and robots. The twelfth, by J. Ichino et al., investigates the psychological effects of color on online documents through a proposed online document interface. The thirteenth paper, by T. Ando et al., studies the robot facial effectiveness in human interpretation. The fourteenth, by T. Ando et al., models robot self-sufficiency applying an urge system focusing on autonomous emotion. This issue has addressed the importance of HSS and highlighted innovative approaches to the development of artificial system more friendly to users. We thank the authors and referees for their ongoing efforts, without which this issue would not have been possible.

1017 荷重変化を考慮した全方向移動型歩行訓練機の経路追従制御(ロボティクス・メカトロニクスVI)

1017 荷重変化を考慮した全方向移動型歩行訓練機の経路追従制御(ロボティクス・メカトロニクスVI)

J1102-2-7 重心のずれを考慮した全方向移動型歩行訓練機の走行制御(ライフサポート2:リハビリテーション・機能制御)

J1102-2-7 重心のずれを考慮した全方向移動型歩行訓練機の走行制御(ライフサポート2:リハビリテーション・機能制御)

1506 力覚センサを用いた意思同定法と全方向移動型歩行補助機への応用(ロボティクス・メカトロニクスV)

1506 力覚センサを用いた意思同定法と全方向移動型歩行補助機への応用(ロボティクス・メカトロニクスV)

1108 全方向移動型歩行訓練機の経路追従制御(ロボティクス・メカトロニクスII)

1108 全方向移動型歩行訓練機の経路追従制御(ロボティクス・メカトロニクスII)