title: Autoregressive-moving-average hidden Markov model for vision-based fall prediction-An application for walker robot.
abstract: Population aging of the societies requires providing the elderly with safe and dependable assistive technologies in daily life activities. Improving the fall detection algorithms can play a major role in achieving this goal. This article proposes a real-time fall prediction algorithm based on the acquired visual data of a user with walking assistive system from a depth sensor. In the lack of a coupled dynamic model of the human and the assistive walker a hybrid "system identification-machine learning" approach is used. An autoregressive-moving-average (ARMA) model is fitted on the time-series walking data to forecast the upcoming states, and a hidden Markov model (HMM) based classifier is built on the top of the ARMA model to predict falling in the upcoming time frames. The performance of the algorithm is evaluated through experiments with four subjects including an experienced physiotherapist while using a walker robot in five different falling scenarios; namely, fall forward, fall down, fall back, fall left, and fall right. The algorithm successfully predicts the fall with a rate of 84.72%.
authors.affiliation: a School of Mechanical Engineering , Shiraz University , Shiraz , Iran.
authors.forename: Sajjad
authors.initials: S
authors.lastname: Taghvaei
authors.affiliation: a School of Mechanical Engineering , Shiraz University , Shiraz , Iran.
authors.forename: Mohammad Hasan
authors.initials: MH
authors.lastname: Jahanandish
authors.affiliation: b Department of Bioengineering and Robotics , Tohoku University , Aoba , Aramaki , Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kosuge
mesh_terms: D000058:Accidental Falls / Q000517:prevention & control*; D000465:Algorithms; D006801:Humans; D008390:Markov Chains; D018670:Monitoring, Ambulatory / Q000295:instrumentation*; D012044:Regression Analysis; D012371:Robotics / Q000295:instrumentation*; D014853:Walkers; D016138:Walking / Q000502:physiology
keywords: autoregressive-moving-average (ARMA) model; hidden Markov model; human fall prediction; walking assistive robot