The work presented in this thesis concerns the identification of vehicle occupant
models. Mathematical models of the vehicle occupant are used in the preliminary
design and development phase of vehicle design. In the design phase, the model is
used to guide the decision on restraint system feasibility. In the development phase
the model is used to suggest solutions to problems associated with the dummy
trajectory or restraint system performance.
Current methods used -to determine such models involve independent component
testing. The conditions under which the components are tested are often not typical
of a crash test, hence iterations of the computer model are needed to successively
improve model and test correlation.
In order to address these problems which cause inaccurate specification of the
mathematical models, an alternative method of data set assembly for crash victim
models is suggested. This alternative method is based on the techniques of system
identification which allow unknown system parameters to be determined from
experimental input/output data.
Initially the viability of using system identification techniques to develop a valid
mathematical model of the vehicle occupant and restraint system was investigated.
This initial study used input and output measurementsfr om computer simulations of
the occupant in frontal impact, as source data for the identification. Effects of
simulated disturbances (noise corrupted output signals) and the effects of simplified
model structure on the identification are also investigated. Several methods for
analysing the likely errors in the identified parameters are defined and discussed in
this simulation study.
Results relating to the identification of seat contact and seat belt characteristics from
physical tests are also presented and these are interpreted in light of the simulation
A Doctoral Thesis. Submitted in partial fulfillment of the requirements for the award of Doctor of Philosophy of Loughborough University.