Design And Evaluation Of A Smart Phone Camera-based Spirometry System

In recent years,more and more researchers put the focus on developing m-health application to provide home care for individuals with lung diseases.One of the subjects is to make clinic spirometers available for patients at home by taking advantage of high technologies,which results from a few reasons.Firstly,traditional spirometers are usually cumbersome and expensive for individuals.Secondly,portable spirometers are relatively out of sight for people living in developing countries.Currently,it has been widely known for some technologies utilizing mobile phone and add-on equipment to assist patients to test their lung functions.However,they still cannot overcome the problems that portable spirometers have because of the fact of using expensive electronics.Besides,a refreshing way of testing lung function by making use of the microphone significantly reduces the cost while it strongly demands a quiet surrounding environment.In this paper,we propose a novel approach to estimate airflow by making use of a smart phone’s camera and image analysis technology to compute the rate of a propeller inside an add-on turbine on a phone.By doing this,it is possible to significantly reduce costs of add-on equipment compared with those employing electronic devices such as infrared detector to calculate the propeller’s rate.Furthermore,another purpose of this paper is to design and implement a mobile phone camera-based spirometry system that is capable to demonstrate the result of our approach.Initially,it is intended to measure four most common parameters in a standard spirometer,which are forced vital capacity(FVC),forced expiratory volume in one second(FEV1),Peak Expiratory Flow(PEF)and FEV1/FVC(FEV1%).The result of experiment by conducting functional and non-functional tests proves all the requirements are satisfied except the accuracy requirement that exceeds the standard scale.However,this paper discusses the relevant factors and the future of improvement.