The Experts below are selected from a list of 22503 Experts worldwide ranked by ideXlab platform

Guozheng Yan - One of the best experts on this subject based on the ideXlab platform.

Kouichi Taji - One of the best experts on this subject based on the ideXlab platform.

  • efficient parametric excitation walking with Delayed Feedback control
    Nonlinear Dynamics, 2012
    Co-Authors: Yuji Harata, Fumihiko Asano, Kouichi Taji
    Abstract:

    In passive dynamic walking proposed by McGeer, mechanical energy lost by heel strike is restored by transporting potential energy to kinetic energy as walking down a slope. When energy input is larger as a slope is steeper, the bifurcation of a walking cycle occurs. In the parametric excitation walking, which is to realize passive dynamic-like walking on the level ground, the bifurcation of a walking cycle has also been observed when walking speed is fast. Recently, Asano et al. have shown that bifurcation exerts an adverse influence upon walking performance by using a rimless wheel model. In this paper, we apply the Delayed Feedback control (DFC), originally used in chaos control, to parametric excitation walking to suppress bifurcation. We show in numerical simulation that the proposed method makes period-two walking to period-one walking, and improves energy efficiency. In addition, the proposed method can generate a sustainable gait in the region where a biped robot cannot walk without DFC. The analyses using a Poincare map reveal that period-one walking with DFC corresponds to an unstable periodic orbit and reveal that a robot model in this paper satisfies the sufficient condition of applicability of DFC.

  • efficient parametric excitation walking with Delayed Feedback control
    Intelligent Robots and Systems, 2009
    Co-Authors: Yuji Harata, Fumihiko Asano, Kouichi Taji
    Abstract:

    In the passive dynamic walking proposed by McGeer, mechanical energy lost by heel strike is restored by transporting potential energy to kinetic energy as walking down a slope. When energy input is large such as an angle of slope is steep, bifurcation of walking period occurs. In parametric excitation walking, which is one method to realize passive dynamic-like walking on level ground, bifurcation has also been observed when walking speed is fast. Recently, Asano et al. have shown that bifurcation exerts an adverse influence upon walking performance by using rimless wheel model. In this paper, we apply Delayed Feedback control (DFC) originally used in chaos control to parametric excitation walking to suppress bifurcation. We show in numerical simulation that the proposed method makes two-period walking to one-period walking, and energy efficiency is improved. The analyses using Poincare map reveal that the one-period walking with DFC is unstable periodic orbit and that the robot dealt in this paper satisfies the sufficient condition of applicability of DFC.

Kestutis Pyragas - One of the best experts on this subject based on the ideXlab platform.

  • control of chaos via an unstable Delayed Feedback controller
    Physical Review Letters, 2001
    Co-Authors: Kestutis Pyragas
    Abstract:

    Delayed Feedback control of chaos is well known as an effective method for stabilizing unstable periodic orbits embedded in chaotic attractors. However, it had been shown that the method works only for a certain class of periodic orbits characterized by a finite torsion. Modification based on an unstable Delayed Feedback controller is proposed in order to overcome this topological limitation. An efficiency of the modified scheme is demonstrated for an unstable fixed point of a simple dynamic model as well as for an unstable periodic orbit of the Lorenz system.

Arvind Kumar Gupta - One of the best experts on this subject based on the ideXlab platform.

  • Delayed Feedback control in a lattice hydrodynamic model
    Communications in Nonlinear Science and Numerical Simulation, 2015
    Co-Authors: Poonam Redhu, Arvind Kumar Gupta
    Abstract:

    Abstract The Delayed-Feedback control (DFC) method for lattice hydrodynamic traffic flow model is investigated on a unidirectional road. By using the Hurwitz criteria and the condition for transfer function in term of H ∞ -norm, we designed the Feedback gain and delay time to stabilize the traffic flow and suppress the traffic jam. The Bode-plot of transfer function have been plotted and discussed that the stability region enhances with Delayed-Feedback control. It is shown that the Delayed-Feedback control method stabilizes the traffic flow and suppresses the traffic jam efficiently. The simulation results are in good agreement with the theoretical analysis.

Yamamoto Naohide - One of the best experts on this subject based on the ideXlab platform.

  • DeFINE: Delayed Feedback based Immersive Navigation Environment for Studying Goal-Directed Human Navigation
    2021
    Co-Authors: Tiwari Kshitij, Kyrki Ville, Cheung Allen, Yamamoto Naohide
    Abstract:

    With the advent of consumer-grade products for presenting an immersive virtual environment (VE), there is a growing interest in utilizing VEs for testing human navigation behavior. However, preparing a VE still requires a high level of technical expertise in computer graphics and virtual reality, posing a significant hurdle to embracing the emerging technology. To address this issue, this paper presents Delayed Feedback based Immersive Navigation Environment (DeFINE), a framework that allows for easy creation and administration of navigation tasks within customizable VEs via intuitive graphical user interfaces and simple settings files. Importantly, DeFINE has a built-in capability to provide performance Feedback to participants during an experiment, a feature that is critically missing in other similar frameworks. To show the usability of DeFINE from both experimentalists' and participants' perspectives, a demonstration was made in which participants navigated to a hidden goal location with Feedback that differentially weighted speed and accuracy of their responses. In addition, the participants evaluated DeFINE in terms of its ease of use, required workload, and proneness to induce cybersickness. The demonstration exemplified typical experimental manipulations DeFINE accommodates and what types of data it can collect for characterizing participants' task performance. With its out-of-the-box functionality and potential customizability due to open-source licensing, DeFINE makes VEs more accessible to many researchers.Comment: 43 pages, 10 figures, 5 tables, Submitted to Behavioral Research Method

  • DeFINE: Delayed Feedback based Immersive Navigation Environment for studying goal-directed human navigation
    Springer New York LLC, 2021
    Co-Authors: Tiwari Kshitij, Kyrki Ville, Cheung Allen, Yamamoto Naohide
    Abstract:

    With the advent of consumer-grade products for presenting an immersive virtual environment (VE), there is a growing interest in utilizing VEs for testing human navigation behavior. However, preparing a VE still requires a high level of technical expertise in computer graphics and virtual reality, posing a significant hurdle to embracing the emerging technology. To address this issue, this paper presents Delayed Feedback based Immersive Navigation Environment (DeFINE), a framework that allows for easy creation and administration of navigation tasks within customizable VEs via intuitive graphical user interfaces and simple settings files. Importantly, DeFINE has a built-in capability to provide performance Feedback to participants during an experiment, a feature that is critically missing in other similar frameworks. To show the usability of DeFINE from both experimentalists’ and participants’ perspectives, a demonstration was made in which participants navigated to a hidden goal location with Feedback that differentially weighted speed and accuracy of their responses. In addition, the participants evaluated DeFINE in terms of its ease of use, required workload, and proneness to induce cybersickness. The demonstration exemplified typical experimental manipulations DeFINE accommodates and what types of data it can collect for characterizing participants’ task performance. With its out-of-the-box functionality and potential customizability due to open-source licensing, DeFINE makes VEs more accessible to many researchers

  • DeFINE: Delayed Feedback based Immersive Navigation Environment for Studying Goal-Directed Human Navigation
    2020
    Co-Authors: Tiwari Kshitij, Kyrki Ville, Cheung Allen, Yamamoto Naohide
    Abstract:

    With the advent of consumer-grade products for presenting an immersive virtual environment (VE), there is a growing interest in utilizing VEs for testing human navigation behavior. However, preparing a VE still requires a high level of technical expertise in computer graphics and virtual reality, posing a significant hurdle to embracing the emerging technology. To address this issue, this paper presents Delayed Feedback based Immersive Navigation Environment (DeFINE), a framework that allows for easy creation and administration of navigation tasks within customizable VEs via intuitive graphical user interfaces and simple settings files. Importantly, DeFINE has a built-in capability to provide performance Feedback to participants during an experiment, a feature that is critically missing in other similar frameworks. To demonstrate the usability of DeFINE from both experimentalists' and participants' perspectives, a case study was conducted in which participants navigated to a hidden goal location with Feedback that differentially weighted speed and accuracy of their responses. In addition, the participants evaluated DeFINE in terms of its ease of use, required workload, and proneness to induce cybersickness. Results showed that the participants' navigation performance was affected differently by the types of Feedback they received, and they rated DeFINE highly in the evaluations, validating DeFINE's architecture for investigating human navigation in VEs. With its rich out-of-the-box functionality and great customizability due to open-source licensing, DeFINE makes VEs significantly more accessible to many researchers.Comment: 42 pages, 10 figures, 5 tables, Submitted to Behavioral Research Method