Comfort Prediction Of Human-Seat System Based On Body Pressure Distribution

In actual driving,the driving experience of the vehicle will be greatly affected by the comfort of the human-seat system.As an objective parameter that reflects the human body load on the seat,the body pressure distribution is extremely important for evaluating the comfort of human-seat system.Based on the static body pressure distribution experiment and the vertical vibration body pressure distribution bench experiment,the statistical analysis method was used to analyze the parameters of static and dynamic body pressure distribution and their influencing factors.Besides,the relationship between the parameters of static body pressure distribution and the subjective comfort score was analyzed.So are as the parameters of dynamic body pressure distribution and the root mean square of weighted acceleration.And based on the parameters of body pressure distribution,the support vector machine regression method was used to establish the regression model to predict the comfort score and the root mean square of weighted acceleration.The main work in this paper was as follows:First of all,static body pressure distribution experiment and vertical vibration body pressure distribution bench experiment were conducted.In the static body pressure distribution experiment,in the case of stimulating the local position including back,thighs,shoulders,buttocks and waist,10 test subjects were required to give static comfort evaluation.In the experiment of dynamic body pressure distribution,the weighted mean square root value was taken as evaluation index of vibration comfort instead of subjective scoring.In order to solve the problem of sensor arrangement interference,the weighted root mean square value was calculated by the transfer function obtained in the transfer function characteristic experiment.In this experiment,5 test subjects were required to sit on two seats with different comfort level,and three different levels of vertical excitation were given by the bench,so that,the dynamic body pressure distribution and the vibration comfort level were obtained simultaneously.Secondly,based on the results of static body pressure distribution,the relationship between the six parameters of average pressure,maximum pressure and contact area of cushion and backrest were analyzed.Based on the results of dynamic body pressure distribution,the relationship between 12 parameters such as average pressure,maximum pressure,contact area and their change rate of cushion and backrest were analyzed.The results showed that the average pressure of the cushion is extremely sensitive to the hip stimulation.And the contact area of the cushion,the average pressure and contact area of the backrest are linearly related to the body BMI.The results also showed that the mean square root values of the average pressure change rate and the contact area change rate of the cushion,and the three parameters of the backrest increase with the growth of the excitation level.At the same time,the maximum pressure and the root mean square value of the maximum pressure change rate are the result of a combination of multiple factors.Besides,the correlation between static body pressure distribution and comfort and that of the dynamic was analyzed by the results of comfort evaluation.The results of the correlation showed that there was a nonlinear correlation between the parameters of static body pressure distribution and subjective comfort.And the six root mean squares of change rate parameters of the dynamic body pressure distribution have a higher correlation with and the vibration comfort.Finally,in order to quantitatively determine the body pressure distribution parameters and the comfort of the human-seat system,the support vector machine regression method was used to establish the prediction model with the body pressure distribution as the attribute parameter,and the comfort of the human-seat system as the prediction object.The result showed that the predictive model of vibration comfort is very accurate,moreover,the support vector machine regression method has higher accuracy than traditional mathematical methods like linear regression and neural network.The above analysis shows that the comfort of human-seat system can be predicted based on body pressure distribution.