Wearable sensory apparatus for multi-segment system orientation estimation with long-term drift and magnetic disturbance compensation

Abstract

Orientation assessment based on wearable sensors is becoming crucial for providing feedback information in wearable robotics and sport monitoring. Gravitational acceleration and Earth’s magnetic field are commonly used as a reference vectors for orientation estimation. This paper presents a novel sensory fusion algorithm for assessing the orientations of human body segments in long-term human walking, and enhance performance in environment with magnetic disturbance. The proposed system was experimentally validated. The results show accurate joint angle measurements (error median below 5°) with no expressed drift over time. The incorporated compensation of magnetic disturbances proved assessment with absolute median errors bellow 2.5°.