Volume 7, Issue 7 (July 2020), Pages: 1-6

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 Original Research Paper

 Title: Dynamics and energy recovery of a walking mechanism

 Author(s): Elvedin Kljuno *, Alan Catovic, Marin Petrovic

 Affiliation(s):

 Mechanical Engineering Faculty, University of Sarajevo, Sarajevo, Bosnia and Herzegovina

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 * Corresponding Author. 

  Corresponding author's ORCID profile: https://orcid.org/0000-0002-5532-8914

 Digital Object Identifier: 

 https://doi.org/10.21833/ijaas.2020.07.001

 Abstract:

Nonlinearity and discontinuity in walking robot dynamics represent a challenge to find adequate control strategies. Walking mechanisms include combined open and closed mechanical chains (loops) consisted of (theoretically) rigid segments. These mechanisms have a relatively high number of degrees of freedom (DOF), which causes that dynamics are represented by complicated differential equations. Complexity is largely expanded if we consider the elasticity of materials within the walking mechanism. Unless we significantly simplify the model of walking mechanism dynamics, model-based controller implementation would require significant computational capacities embedded into the hardware. This paper presents dynamics modeling, controller design, and mechanical energy analysis of a walking robot with elastic strings. The paper shows how to analyze the capability of the walking mechanism with elastic elements to reuse mechanical energy throughout the walking cycle. Energy Recovery Ratio is an efficiency measure that is conceptually adopted from biology. The novelty introduced here is represented by a generalization of the parameter and the analysis to cover non-steady walk with interchanged accelerations and decelerations. The paper shows an analysis of the way biological walkers store and reuse energy cyclically during every step. The walking robot architecture with elastic strings mimics the biological architecture to a certain extent. Based on the kinematic and dynamic analysis of the robot, the mathematical model is formed, which is then used for the controller design implemented in hardware. 

 © 2020 The Authors. Published by IASE.

 This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

 Keywords: Walking robot, String-driven, Mechanical energy, Controller

 Article History: Received 5 January 2020, Received in revised form 22 March 2020, Accepted 23 March 2020

 Acknowledgment:

No Acknowledgment.

 Compliance with ethical standards

 Conflict of interest: The authors declare that they have no conflict of interest.

 Citation:

 Kljuno E, Catovic A, and Petrovic M (2020). Dynamics and energy recovery of a walking mechanism. International Journal of Advanced and Applied Sciences, 7(7): 1-6

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 Figures

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 Tables

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