Age Differences in Occupant Motion during Simulated In-Vehicle Swerving Maneuvers

Area of Science:

• Biomechanics
• Human Factors
• Automotive Safety

Background:

• Increasing availability of active safety and automated vehicle features may lead to more frequent evasive swerving maneuvers.
• Pre-crash vehicle dynamics can significantly impact occupant restraint effectiveness and associated injury risks.

Purpose of the Study:

• To investigate and quantify the influence of age on occupant kinematic, kinetic, and muscular responses during evasive swerving.
• To understand how age affects responses to sudden vehicle movements in crash scenarios.

Main Methods:

• On-road testing involving seat belt-restrained participants across three age groups: children (10-12 years), teens (13-17 years), and adults (21-33 years).
• Two distinct evasive swerving maneuvers were performed in a contemporary sedan on a test track.
• Analysis of occupant kinematics, electromyography (muscle activity), and seat belt load distribution.

Main Results:

• Children demonstrated significantly greater head and trunk motion compared to teens and adults in the into-the-belt direction (p < 0.03).
• Muscle activation in the into-the-belt direction was similar across all age groups.
• In the out-of-the-belt direction, children's head and trunk motion more closely resembled older groups (p < 0.02), but with elevated muscle activation.

Conclusions:

• Children display unique neuromuscular control strategies for head and trunk motion relative to adolescents and adults.
• Significant age-related differences exist in the interplay between kinematics and muscle activation during evasive maneuvers.
• Findings offer valuable validation data for active human body models across a wide age spectrum.