Optimization of Sitting Posture Classification based on Anthropometric Data

Leonardo Martins, Bruno Ribeiro, Rui Almeida, Hugo Pereira, Adelaide Jesus, Cláudia Quaresma, Pedro Vieira


An intelligent chair prototype was developed in order to detect and correct the adoption of bad sitting postures during long periods of time. A pneumatic system was enclosed in the chair (4 air bladders inside the seat pad and 4 in the backrest) to classify 12 standardized sitting postures, with a classification score of 80.9%. Recently we used algorithmic optimization applied to the existing classification algorithm (based on Neural Networks) to split users (using Classification Trees) by their sex and used two different previously trained Neural Networks (Male and Female) to get an improved classification of 89.0% when the user was identified and 87.1% for unidentified users. In this work we aim to investigate the usage of the anthropometric information (height and weight) to further optimize our classification process. Here we use four Machine Learning Techniques (Neural Networks, Support Vector Machines, Classification Trees and Naive Bayes) to automatically split the users in 2 classes (above and below the specific anthropometric median value). Results showed that Classification Trees worked best on automatically separating the body characteristics (i.e. Height) with a global optimization of 88.3%. During the classification process, if the user is identified, we skip the splitting step, and this optimization increases to 90.2%.


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Paper Citation

in Harvard Style

Martins L., Ribeiro B., Almeida R., Pereira H., Jesus A., Quaresma C. and Vieira P. (2016). Optimization of Sitting Posture Classification based on Anthropometric Data . In Proceedings of the 9th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 5: HEALTHINF, (BIOSTEC 2016) ISBN 978-989-758-170-0, pages 406-413. DOI: 10.5220/0005790104060413

in Bibtex Style

author={Leonardo Martins and Bruno Ribeiro and Rui Almeida and Hugo Pereira and Adelaide Jesus and Cláudia Quaresma and Pedro Vieira},
title={Optimization of Sitting Posture Classification based on Anthropometric Data},
booktitle={Proceedings of the 9th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 5: HEALTHINF, (BIOSTEC 2016)},

in EndNote Style

JO - Proceedings of the 9th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 5: HEALTHINF, (BIOSTEC 2016)
TI - Optimization of Sitting Posture Classification based on Anthropometric Data
SN - 978-989-758-170-0
AU - Martins L.
AU - Ribeiro B.
AU - Almeida R.
AU - Pereira H.
AU - Jesus A.
AU - Quaresma C.
AU - Vieira P.
PY - 2016
SP - 406
EP - 413
DO - 10.5220/0005790104060413