Document Type : Full Research Paper


1 Assistant Professor, Department of Mechanical Engineering, Faculty of Mechanical and Industrial Engineering, Islamic Azad University, Qazvin Branch

2 Professor, Department of Medical Physics and Engineering, Faculty of Medicine, Medical Campus, Shahid Beheshti University

3 Assistant Professor, Department of Biomedical Engineering, Faculty of Engineering, Shahed University

4 Assistant Professor, Department of Biomedical Engineering, Science and Research Branch, Islamic Azad University



In this study a simple inverted pendulum model with PID controller and delayed feedback is used to model standing-still postural control system for the purpose of achieving useful information about its underlying control structure. Using the Genetic algorithm and an experimental study results, the model and the controller parameters were estimated in a way that the model mimics real experimental sway patterns. The controller parameters found meaningful interpretations and it is shown that degeneration of postural control system affects the values of the parameters. Our findings indicate that although the simple models are not able to describe complexities of postural control system and interactions between its components, they can help us to improve our understanding of postural control system, its performance, its features and the way that the features change.


Main Subjects

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