Joint angle estimation with accelerometers for dynamic postural analysis

• Published in: Journal of biomechanics Vol. 48; no. 13; pp. 3616 - 3624
• Main Authors: Ma, Jianting, Kharboutly, Haissam, Benali, Abderraouf, Benamar, Faïz, Bouzit, Mourad
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 15.10.2015; Elsevier Limited; Elsevier
• Subjects: Accelerometers; Accelerometry; Algorithms; Ankle Joint - physiology; Automatic; Biomechanical Phenomena; Biomechanics; Coders; Dynamics; Encoders; Engineering Sciences; Hip Joint - physiology; Human; Humans; Inverted pendulum; Joint estimation; Knee Joint - physiology; Mechanics; Models, Anatomic; Omnidirectional mobile platform; Perturbation methods; Physical Medicine and Rehabilitation; Platforms; Postural Balance; Postural disturbance; Posture; Regression Analysis; Sensors; Studies; Tri-axial accelerometer; Inverted pendulum; Joint estimation; Omnidirectional mobile platform; Tri-axial accelerometer; Postural disturbance
• ISSN: 0021-9290; 1873-2380; 1873-2380
• DOI: 10.1016/j.jbiomech.2015.08.008

This paper presents a new accelerometer based method for estimating the posture of a subject standing on a dynamic perturbation platform. The induced perturbation is used to study the control mechanisms as well as the balance requirements that regulate the upright standing. These perturbations are translated into different intensity levels of speed and acceleration along longitudinal and lateral directions of motion. In our method, the human posture is modeled by a tridimensional, three-segment inverted pendulum which simultaneously takes into account both the anterior–posterior and medio-lateral strategies of hip and ankle. Four tri-axial accelerometers are used her, one accelerometer is placed on the platform, and the other three are attached to a human subject. Based on the results, the joint angle estimated compare closely to measurements from magnetic encoders placed on an articulated arm joint. The results were also comparable to those found when using a high-end optical motion capture system coupled with advanced biomechanical simulation software. This paper presents the comparisons of our accelerometer-based method with encoder and optical marker based method of the estimated joint angles under different dynamics perturbations.