A virtual prototyping toolkit for assessment of child restraint system (CRS) safety

Computational modeling continues to play an increasingly significant role in the design of more effective vehicle crash safety systems. Models configured with sophisticated computer analyses permit researchers to perform extensive "what-if?" exploratory studies at a fraction of the cost and time that would be required by physical testing alone. Presently, our research team is developing a modeling and analysis capability that will provide child restraint system (CRS) engineers, designers, and analysts a validation tool that will supplement conventional engineering results attained from sled testing, which is often timely and costly. Supplementing these physical tests and digital modeling capabilities is the newly developed NYSCEDII CRS Visualization Module (NCVM), which allows a user to immersively visualize the MADYMO-calculated automotive crash simulation imagery. Depicted are the motion of, and interactions between, the CRS shell, human "dummy", harness and latch belt assemblies, and applicable vehicle cabin-interior surfaces and structure; and nodal finite element Von Mises color stress contours for the CRS shell and its attendant restraint straps. Supplemental NCVM features include: plotted instantaneous body segment acceleration-time responses; dummy displacements visually tracked using on-screen reference markers - to be tracked as a function of time; forwards or backwards animation capability; and stereo viewing, using anaglyphic stereo, to convey a sense of depth and immersion. This paper demonstrates the utility of the NCVM using a combination conventional/finite element system model of a recent-production child restraint system (CRS) and its three-year-old dummy occupant in a modified FMVSS 213 sled test environment.