Research On The Techniques Of Sitting Posture Surveillance For Teenagers Based On Kinect

Modern life has made more and more people become "sedentary",while the long-term habit of unhealthy sitting posture may cause great harm to the health of human body.Especially for the teenagers who are at the stage of physical development,maintaining wrong sitting posture will cause too close sight distance and too much pressure on the spine,which will lead to myopia,cervical spondylosis and spinal deformity.Therefore,it is of great significance to help teenagers to correct their wrong sitting posture in time and even form a habit of healthy sitting posture.In order to solve this problem,this thesis studied the related techniques of sitting posture surveillance for teenagers.Compared with traditional physical wearable correcting devices and simple electronic devices based on acceleration sensor or level sensor,the sitting posture recognition method based on machine vision technology is more precise and flexible.And compared with traditional vision technology based on 2D image,3D image will not be affected by illumination and occlusion.Therefore,this thesis use Kinect depth sensor for sitting posture surveillance and recognize the sitting posture by joint information.The main research work of this thesis is as follows:(1)In this thesis,we designed and implemented a surveillance system based on Microsoft Kinect.Through calculating the angle between connections of users' joint points and compared the angles of users in different standard sitting postures,so that we could judge the sitting posture of users and give the reasons for their errors.The experiment verifies the accuracy of the system for the sitting posture judgment.(2)The Kinect may get wrong joint's location information if the observation condition is not ideal.In order to solve this problem,the recovery method of joint information for Kinect is studied in this thesis.According to the structure of human body and the principle of motion continuity,we can judge the credibility of joint's information obtained from Kinect,and repair the inaccurate information.The accuracy of the sitting posture surveillance system is improved effectively.(3)Through the research of posture and action recognition method,we implemented the function of posture recognition based on joint angle measurement and the function of common action(drinking and answering the phone)recognition based on HMM.By posture recognition,the system can automatically switch the judgment standard of sitting posture according to the sitting posture and behavior status of the user.These functions greatly improve the practicability of the system.(4)This thesis formulated a positive and effective persuasion strategy that can promote the teenagers realize the problem of sitting posture in time,and help them develop a habit of healthy sitting posture,so that would avoid the harm caused by unhealthy sitting posture,protect the eyesight,and promote the regular growth and development of the body.The effectiveness of the persuasion strategy of sitting posture was verified by experiments.