Postural and Muscular Responses of Car Occupants under Pre-Crash Conditions
Doctoral thesis, 2021
A set of in-vehicle experiments was carried out in which front-row passengers were traveling at 73 km/h and subjected to autonomous lane changes and lane changes combined with braking, each with two belt configurations: standard and reversible pre-pretensioner belts. Volunteer muscle activations were measured by the surface electromyography (EMG) technique. Transformation of coordinates corresponding to several film targets attached to the head and upper torso was used to calculate the kinematics in 3-D. The volunteers’ EMG and kinematics were processed, and the quantified kinematics were statistically explored using principal component analysis and linear mixed model.
Compared to the standard belt, pre-tensioning the seat belt prior to the maneuvers reduced lateral and forward displacements of the head and upper torso significantly. Seat belt pre-tensioning was also associated with earlier muscle activation onset and significantly lower activation amplitude for specific muscles. The influence of sex, stature, and their interaction on the head and upper torso kinematics were found statistically significant but accounted for a small amount of variance. A statistical model was developed which can predict head and upper torso kinematics of occupants with different stature and sex.
The data provided in this thesis can be used for further enhancement and validation of HBMs. Consequently, the design of integrated safety systems in modern cars can benefit from more biofidelic models representing a wide range of population more accurately. Further statistical investigations for other types of omnidirectional loading scenarios and, preferably with a larger and more diverse sample space, are required to establish more accurate statistical models that can be generalized to the whole population.
principal component analysis
linear mixed model
vehicle occupant kinematics
human body model
Chalmers, Mechanics and Maritime Sciences, Vehicle Safety, Injury Prevention
Passenger kinematics in Lane change and Lane change with Braking Manoeuvres using two belt configurations: standard and reversible pre‐pretensioner
2018 IRCOBI Conference Proceedings- International Research Council on the Biomechanics of Injury,; (2018)p. 493-511
Paper in proceeding
Passenger muscle responses in lane change and lane change with braking maneuvers using two belt configurations: Standard and reversible pre-pretensioner
Traffic Injury Prevention,; Vol. 20(2019)p. S43-S51
Female kinematics and muscle responses in lane change and lane change with braking maneuvers
Traffic Injury Prevention,; Vol. 22(2021)p. 236-241
Ghaffari G, Iraeus J, and Davidsson J. The effect of age, stature, and sex on passenger kinematics in lane change maneuvers
Active human body models for virtual occupant response, step 3
VINNOVA (2014-03931), 2014-10-01 -- 2017-12-31.
Future Occupant Safety for Crashes in Cars (OSCCAR)
European Commission (EC) (769947-OSCCAR), 2018-06-01 -- 2021-05-31.
Electrical Engineering, Electronic Engineering, Information Engineering
Areas of Advance
Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 5002
Chalmers University of Technology
Vasa B-salen, Vasa Hus 2, Vera Sandbergs Alle 8, Göteborg (physical attendance by invitation only).
Opponent: universitetslektor (associate professor) Francisco José López-Valdés, från Comillas Pontifical Universitet i Madrid, Spain