Document Type : Full Research Paper

Authors

• Davoud Naderi ¹
• Mohsen Sadeghi Mehr ²
• Nader Farahpour ³
• Behnam Miripour-Fard ⁴

¹ Assistant Professor, Mechanical Engineering Department, Engineering School, Bu-Ali Sina University

² Assistant Professor, Mechanical Engineering Department, Engineering School, Bu-Ali Sina University ,

³ Associate Professor, Physical Education and Sport Science Department, Literature and Humanities School, Bu-Ali Sina University ,

⁴ M.Sc Student of Mechanical Engineering, Engineering School, Bu-Ali Sina University

Abstract

Cognition of human postural responses can provide valuable insight on the control of stability. Researchers can use this finding to design rehabilitation exercises to improve the patients, balance. This study was done with the aim of conducting theoretical and experimental investigations on human response to tilting base plate in the sagittal plane. A four-segment model with three degrees of freedom was used as a biomechanical model of human body and its motion was studied in the sagittal plane. The postures of model were found by optimization technique such that the stability of model to be optimum. Zero moment point stability criterion was applied to find the optimum posture against the tilting base plate. To verify the theoretical results experimentally, the stability measure device was designed and manufactured. In several trials, the responses of ten male healthy persons standing on a tilting platform under perturbations were recorded by using the motion analysis system. Through data analysis, the response of each subject was surveyed and the experimental and theoretical results were compared. Both the experimental and theoretical results showed that the human central nervous system evokes the ankle strategy to keep its balance under tilting base plate conditions. A good coincident between the experimental results and theoretical predictions was observed, indicating that the model basis optimization method can be well relied upon to predict the human joints angle trajectories in response to base plate tilting. 

Keywords

• Human stability
• Tilting platform
• Sagittal plane
• dynamic modeling
• Optimization
• Motion analysis system

Main Subjects

• Gait Analysis
• Spinal Biomechanics
• Biomechanical Motor Control / Motor Control of Human Movement
• Human Movement Modeling
• Neuro-Muscular Engineering