Seat surface pressure distributions of Hybrid III dummies and Occupant Classification Anthropomorphic Test Devices (OCATDs) representing small adult women and six-year-old children were recorded in a range of postures on two test seats. Support forces under the feet and surrogate postures were also measured. The pressure distribution data were analysed using quantitative metrics developed in previous testing with human subjects. Both the Hybrid IIIs and OCATDs were found to be reasonable representative of similarly sized humans but the OCATD6 performance was slightly better than the six-year-old Hybrid III on some parameters. In repeated trials, the coefficient of variance of pressure distribution parameters for all surrogates was generally less than 5%, compared with a 30% difference in target values between the child and adult surrogates. Positioning repeatability was better for the child surrogates than for the adult surrogates. The pressure distribution and foot support forces produced by the adult surrogates are strongly influenced by foot position. The data illustrate some of the challenges faced by seat-based occupant classification systems and suggest that pressure-distribution-related parameters may be a useful complement to seat weight sensor data. (Author/publisher)
Samenvatting