title: FreeWalker: a smart insole for longitudinal gait analysis.
abstract: Gait analysis is an important diagnostic measure to investigate the pattern of walking. Traditional gait analysis is generally carried out in a gait lab, with equipped force and body tracking sensors, which needs a trained medical professional to interpret the results. This procedure is tedious, expensive, and unreliable and makes it difficult to track the progress across multiple visits. In this paper, we present a smart insole called FreeWalker, which provides quantitative gait analysis outside the confinement of traditional lab, at low- cost. The insole consists of eight pressure sensors and two motion tracking sensors, i.e. 3-axis accelerometer and 3-axis gyroscope. This enables measurement of under-foot pressure distribution and motion sequences in real-time. The insole is enabled with onboard SD card as well as wireless data transmission, which help in continuous gait-cycle analysis. The data is then sent to a gateway, for analysis and interpretation of data, using a user interface where gait features are graphically displayed. We also present validation result of a subject's left foot, who was asked to perform a specific task. Experiment results show that we could achieve a data-sampling rate of over 1 KHz, transmitting data up to a distance of 20 meter and maintain a battery life of around 24 hours. Taking advantage of these features, FreeWalker can be used in various applications, like medical diagnosis, rehabilitation, sports and entertainment.
authors.forename: Baitong
authors.initials: B
authors.lastname: Wang
authors.forename: Kuldeep Singh
authors.initials: KS
authors.lastname: Rajput
authors.forename: Wing-Kin
authors.initials: WK
authors.lastname: Tam
authors.forename: Anthony K H
authors.initials: AK
authors.lastname: Tung
authors.forename: Zhi
authors.initials: Z
authors.lastname: Yang
mesh_terms: D061725:Accelerometry / Q000295:instrumentation; D003196:Computer Graphics; D003201:Computers; D004867:Equipment Design; D005528:Foot; D005684:Gait / Q000502:physiology*; D006801:Humans; D018670:Monitoring, Ambulatory / Q000295:instrumentation* / Q000379:methods*; D009038:Motion; D012775:Shoes; D012984:Software; D016138:Walking