Online Activity Matching Using Wireless Sensor Nodes

Arie Horst, Nirvana Meratnia

    Research output: Chapter in Book/Report/Conference proceedingConference contributionAcademicpeer-review


    In this paper, we explore the capability of wireless sensor networks to perform online activity matching for sport coaching applications. The goal is to design an algorithm to match movements of a trainee and a trainer online and to find their spatial and temporal differences. Such an algorithm can aid the trainer to better observe performance of the trainees in group lessons. We consider fitness-like movements such as those performed in aerobic. We also limit ourselves to only having one sensor node on the trainer and one sensor node on the trainee, however our algorithm scales well to more trainees per trainer. We use Sun SPOT sensor nodes and use the accelerometer and gyroscope sensors to capture the movements. The gravity vector is extracted and improved with a Kalman filter using the accelerometer and gyroscope data. An automatic segmentation technique is developed that examines the movement data for rest and activity periods and changes in movement direction. The segmentation and the movement information are communicated with the node of the trainee where the movements are compared. We choose to use Dynamic TimeWarping (DTW) to perform the spatial and temporal matching of movements. Because DTW is computationally intensive, we develop an optimized technique and provide feedback to the trainee. We test all the design choices extensively using experiments and perform a system test using different test methods to validate our approach.
    Original languageUndefined
    Title of host publicationProceedings of the First International Conference on Pervasive and Embedded Computing and Communication Systems, PECCS 2011
    Place of PublicationPortugal
    PublisherSCITEPRESS – Science and Technology Publications
    Number of pages10
    ISBN (Print)978-989-8425-48-5
    Publication statusPublished - 5 Mar 2011

    Publication series

    PublisherSciTePress – Science and Technology Publications


    • METIS-277587
    • EWI-19832
    • IR-76455

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