Study On The Design Of Myopia Prevention Seat For School-age Children

The poor sitting posture is an important predisposing factor that leads to the high incidence of myopia in school-age children.Intervention of reading and writing postures and related near-sighted behavior is one of the key points to prevent the development of myopia.This paper starts with the seat design.By analyzing the physiological factors of the sitting posture,it is found that the kneeling posture can help the spine close to the natural upright position and increase the visual distance of the working sitting posture.A link between the myopia prevention and seat design was established.Firstly,the visual distance and comfort of school-age children in normal and kneeling sitting positions were studied by using the videography,surface electromyography,and subjective evaluation methods,and verified the effectiveness validity of kneeling sitting on visual distance control.Secondly,the effects of different seat angles and leg support inclination angles of kneeling seat on the visual distance and sitting comfort of school-age children were studied through controlled experiments.The data collected in the two groups of experiments included sitting posture images,surface electromyography data,and subjective scores.The Python,Photoshop 2020,Image J,and Matlab?R2016b were used for image selection,image correction,visual distance measurement,and respectively.In the surface electromyography data analysis,is used for EMG signal data calculation.The experiments used IBM SPSS Statistics 2 for one-way analysis of variance,paired-samples T test and multiple comparisons.The main results are summarized as follows:1.Kneeling seats can increase the visual distance of college-age children during reading and writing tasks and help prevent myopia;2.Compared with ordinary sitting posture,the comfort of kneeling sitting for schoolage children is lower than that of ordinary seats;3.The result showed that the kneeling seats at 10°,20°,and 30° seat inclination have a significant impact on the comfort level of school-age children's erector spinae and gastrocnemius.Among them,the lumbar erector spinae of school-age children are the most comfortable at a seat angle of 30° and leg support angle of 30°,while the leg gastrocnemius is the most uncomfortable;4.It was found that the knee support of 20°,30°,and 40° kneeling seats significantly effects the comfort level of the school-age children's gastrocnemius,but less effects the lumbar erector spinae.Among them,the gastrocnemius has the highest comfort level under the leg support of 30° and the seat angle of 20°;5.Based on the comfort level of waist and legs,the 20°seat inclination and 30°leg support are used as the design basis for subsequent child myopia prevention seats.This paper applies the experimental conclusions to the design of school-age children's seats.In the analysis of the characteristics of school-age children,the survey results show that more than 50% of school-age children often use forward sitting posture when reading and writing,while the proportion of backward sitting posture is not high;Long-time use of traditional learning chairs tend to cause the neck soreness,lower back pain,and sore eyes,while there is less soreness in the lower limbs soreness.This article also clarifies the design objects and user requirements.On this basis,product design is carried out from three aspects: functional elements,size elements and visual elements.In the design practice stage,a number of initial model schemes were produced,and finally one scheme was selected for modification and improvement.After the product design is completed,the product design evaluation and reliability evaluation are carried out.We invited five experts to evaluate and score the designed products and the market products using the ranking scoring method.The results show that the designed seat in this paper has the highest comprehensive score.In addition,16 participants were invited to perform usability tests on the physical model,and scored using the System Usability Scale,which finally verified that the products designed in this paper generally meet the usability evaluation standards.Finally,design a myopias prevention seat for school-age children that can increase the visual distance to prevent myopia,and at the same time have a certain degree of comfort.This paper provides a new way for designing myopia prevention products for school-age children.