Real-time gait event detection for normal subjects from lower trunk accelerations☆
Received 13 May 2009; received in revised form 23 October 2009; accepted 19 November 2009. published online 25 December 2009.
Abstract
In this paper we report on a novel algorithm for the real-time detection and timing of initial (IC) and final contact (FC) gait events. We process the vertical and antero-posterior accelerations registered at the lower trunk (L3 vertebra). The algorithm is based on a set of heuristic rules extracted from a set of 1719 steps. An independent experiment was conducted to compare the results of our algorithms with those obtained from a Digimax force platform. The results show small deviations from times of occurrence of events recorded from the platform (13±35ms for IC and 9±54ms for FC). Results for the FC timing are especially relevant in this field, as no previous work has addressed its temporal location through the processing of lower trunk accelerations. The delay in the real-time detection of the IC is 117±39ms and 34±72ms for the FC, improving previously reported results for real-time detection of events from lower trunk accelerations.
☆Disclaimer: All the authors were fully involved in the study and preparation of the manuscript. The material within has not been and will not be submitted for publication elsewhere.
ABSTRACT