Dynamic Seat Design For Relieving Sedentary Injuries Based On EMG Analysis

With the rapid development of the Internet.People’s work and lifestyle also changed,and sedentary situations were more frequent.Health problems caused by long sitting time are also more serious.Effective relief of sedentary problem and relief of sedentary injuries can affect the overall level of human health,which has a certain social value.This paper takes the sedentary people as the research object,and analyses the common seats on the market and intelligent products to alleviate sedentary injuries.According to the needs of sedentary users and the fact that most products can not effectively alleviate the waist and back injuries caused by sedentary,the problem of bad sitting posture can’t be corrected without paying attention to users’ micro-dynamic behavior during sedentary process.Based on the theory of ergonomics,the user’s sedentary state was observed and analyzed,and a new way of seat interaction and product strategy to relieve sedentary injuries and correct sitting posture were obtained.Furthermore,the surface electromyography experiment was conducted to compare and record the changes of the lower waist muscle activity level in the sedentary behavior of users under the new strategy and the normal static sitting posture.Six subjects were collected through the electromyograph in three sitting states: forward,upright and backward,and the seat inclination angle gradually increased in a certain range after the sedentary behavior appeared,which promoted the unconscious situation of users.The surface electromyogram(EMG)signals of the lumbar erector spine muscles during the lower active micro-movement were analyzed in time domain and frequency domain.According to the experimental results,the product strategy and the interactive mode of seats are improved,and the innovative design of seats is carried out.The experimental results show that there is no obvious fatigue in the muscleduring the micro-dynamic sedentary process under the traditional static posture and the new strategy,but the anti-fatigue performance of the muscle is the best under the product strategy which urges users to take the initiative to microexercise.Experiments show that the inclination angle of the chair surface increases gradually during the sedentary process,which promotes the user to perform micro-motion under unconscious state.The new product interaction mode can effectively alleviate sedentary injuries and make the user actively straighten his chest to correct the bad sitting posture and reduce the degree of sedentary injuries.Finally,according to the experimental results,the new seat product strategy and interaction mode are designed on the shape,function and material,so that the seat product can not only alleviate sedentary injuries,but also have a good user experience.User evaluation has been carried out and the shortcomings of the product have been improved in the future design.It provides a new design idea for similar seat products and a new idea for relieving sedentary injuries and reducing sedentary behavior.