Visual and Human-Interpretable Feedback for Assisting Physical Activity

Abstract

Abstract. Physical activity is essential for stroke survivors for recovering some autonomy in daily life activities. Post-stroke patients are initially subject to physical therapy under the supervision of a health professional, but due to economical aspects, home based rehabilitation is eventually suggested. In order to support the physical activity of stroke patients at home, this paper presents a system for guiding the user in how to properly perform certain actions and movements. This is achieved by presenting feedback in form of visual information and human-interpretable messages. The core of the proposed approach is the analysis of the motion required for aligning body-parts with respect to a template skeleton pose, and how this information can be presented to the user in form of simple recommendations. Experimental results in three datasets show the potential of the proposed framework.

Video-based Feedback for Assisting Physical Activity

“…As proposed in [Antunes et al, 2016b], we represent a skeleton S by a set of body parts B = {b 1 , · · · , b P }, where P is the number of body parts and each body part b k is defined by n k joints Given two corresponding skeletons S i of M andŜˆi ofM, the goal of the physical activity assistance system proposed in [Antunes et al, 2016b] is to compute the motion that each body part of S i needs to undergo to better matchŜˆi. This is achieved by computing for each body part b k the rigid motion that increases the similarity between its corresponding body partsb k .…”

“…Recently, Antunes et al [Antunes et al, 2016b] introduced a system able to provide feedback in the form of visual information and human-interpretable messages in order to support a user in improving a movement being performed. The motivation is to support the physical activity of post-stroke patients at home, where they are guided in how to correctly perform an action.…”

“…For example, a template action can be a video created by a physiotherapist with a specific movement for the patient to reproduce. We propose to extend the framework of [Antunes et al, 2016b] in order to provide real-time feedback with respect to the template action instead of a single pose or presegmented video clips as [Antunes et al, 2016b]. To that end, an important alignment problem needs to be solved between the performed action and the template action.…”

“…Two approaches from the literature are suitable for solving this problem, namely, Subsequence-DTW (SS-DTW) [Müller, 2007] and Temporal Commonality Discovery (TCD) [Chu et al, 2012]. In this paper, we propose to adapt both SS-DTW and TCD for the feedback system in [Antunes et al, 2016b] and evaluate the performance of both alignment methods and the corresponding feedback. This paper is organized as follows: Section 2 introduces the problem formulation of the feedback system proposed in [Antunes et al, 2016b].…”

“…In this paper, we propose to adapt both SS-DTW and TCD for the feedback system in [Antunes et al, 2016b] and evaluate the performance of both alignment methods and the corresponding feedback. This paper is organized as follows: Section 2 introduces the problem formulation of the feedback system proposed in [Antunes et al, 2016b]. Section 3 provides a brief introduction of temporal alignment and proposes to adapt SS-DTW and TCD for the feedback system.…”