title: Camera on Vessel: A Camera-Based System to Measure Change in Water Volume in a Drinking Glass.
abstract: A major problem related to chronic health is patients' "compliance" with new lifestyle changes, medical prescriptions, recommendations, or restrictions. Heart-failure and hemodialysis patients are usually placed on fluid restrictions due to their hemodynamic status. A holistic approach to managing fluid imbalance will incorporate the monitoring of salt-water intake, body-fluid retention, and fluid excretion in order to provide effective intervention at an early stage. Such an approach creates a need to develop a smart device that can monitor the drinking activities of the patient. This paper employs an empirical approach to infer the real water level in a conically shapped glass and the volume difference due to changes in water level. The method uses a low-resolution miniaturized camera to obtain images using an Arduino microcontroller. The images are processed in MATLAB. Conventional segmentation techniques (such as a Sobel filter to obtain a binary image) are applied to extract the level gradient, and an ellipsoidal fitting helps to estimate the size of the cup. The fitting (using least-squares criterion) between derived measurements in pixel and the real measurements shows a low covariance between the estimated measurement and the mean. The correlation between the estimated results to ground truth produced a variation of 3% from the mean.
authors.affiliation: Designed Intelligence, Department of Industrial Design, Technische Universiteit Eindhoven, The Netherlands. i.b.i.ayoola@tue.nl.
authors.forename: Idowu
authors.initials: I
authors.lastname: Ayoola
authors.affiliation: Designed Intelligence, Department of Industrial Design, Technische Universiteit Eindhoven, The Netherlands. w.chen@tue.nl.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.affiliation: Designed Intelligence, Department of Industrial Design, Technische Universiteit Eindhoven, The Netherlands. l.m.g.feijs@tue.nl.
authors.forename: Loe
authors.initials: L
authors.lastname: Feijs
mesh_terms: D004326:Drinking; D005898:Glass; D006801:Humans; D007091:Image Processing, Computer-Assisted; D010781:Photography / Q000295:instrumentation*; D014867:Water
chemical_list: D014867:Water
keywords: camera vision; chronic patients; fluid imbalance; fluid level measurement; fluid monitoring