Research On Degree Modeling And Objective Evaluation Method Of Vehicle Occupant Motion Sickness

Motion sickness among car occupants has a long history.With the deepening of vehicle intelligence research and the promotion of autonomous driving travel services,ride comfort has become one of the main demands of passengers for autonomous vehicles,among which vehicle motion sickness has the greatest impact on ride comfort.Therefore,accurate prediction and evaluation of occupant motion sickness level under actual working conditions is of great significance to optimize vehicle motion state and actively mitigate occupant motion sickness symptoms.Therefore,aiming at accurately estimating and evaluating the level of occupant motion sickness,this paper proposed a motion sickness degree model for occupant motion sickness from the perspective of vehicle motion.The stimulation degree of occupant motion sickness caused by current driving path and driving behavior was evaluated through vehicle motion state,so as to optimize subsequent motion state of vehicle and slow occupant motion sickness.At the same time,on the basis of the active evaluation method of motion sickness,the objective evaluation method of motion sickness was studied through motion sickness experiment,and the physiological state of the occupant was used to represent the level of motion sickness.Its specific research contents are as follows:Firstly,analyzing the mechanism of occupant motion sickness is the basis of accurately evaluating occupant motion sickness degree.From the perspective of human vestibular system,this paper qualitatively analyzed the mechanism of human motion sickness,and on the basis of sensory conflict theory and subjective vertical conflict theory,from the perspective of vehicle movement,analyzed the inducement of car occupant motion sickness.Secondly,based on the dynamic characteristics of human vestibular organs and with the help of classical control theory and Kalman filter method,this paper quantified the calculation model of human motion sickness sickness and selected the parameters in combination with the existing motion sickness experiment data.Considering that the motion state of the vehicle itself is easier to obtain than the motion state of the human head during actual driving,a linear chain structure composed of the sprung mass of the vehicle,the upper body of the passenger and the head of the passenger was established from the perspective of human sensory perception,and the conversion between the motion state of the vehicle and the motion state of the passenger’s head was realized through the Newton-Euler dynamic derivation.Combined with the two,the motion sickness model of car occupant motion sickness was constructed,which can predict the motion sickness level of the occupant according to the motion state of the vehicle.Thirdly,based on the vehicle motion characteristics that are easy to cause occupant motion sickness,this paper extracted the driving condition characteristics that stimulate occupant motion sickness,and established the simulation test condition accordingly to verify the effectiveness of the model in predicting different levels of occupant motion sickness induced by different driving paths.The head motion data of the vehicle and the subject were recorded through the human-in-the-loop experiment.The subjective evaluation method was used to evaluate the motion sickness state of the subject,and the subjective evaluation measurement results were used as the scale to optimize the model parameters,so that the accuracy of the model prediction results was significantly improved.Simulation and experimental results showed that the motion sickness model proposed in this paper can effectively predict the level of occupant motion sickness.Finally,this paper analyzed the development and application status of objective evaluation methods for motion sickness based on the changing characteristics of physiological characteristics when human body has motion sickness symptoms.Based on this,objective evaluation methods were introduced in the real car experiment to jointly evaluate the motion sickness state of subjects with subjective evaluation methods,and explore the effectiveness of physiological characteristics in characterizing motion sickness state.The analysis results showed that there is a significant correlation between HRV signal and GSR signal and the level of motion sickness.