The system carries out continuous in-vehicle data measurement and storage
for subsequent processing. A given driving manoeuvre is sub-divided into
facets and the measured vehicle data is processed to provide a local
rating for each of the facets using empirically derived transfer
functions. The local ratings are weighted and combined to provide an
overall rating which is converted to a rating out of ten based on a
further transfer function based on correlations between derived and
subjectively observed ratings. As a result, driveability rating and
engine calibration/development can be accelerated and targeted.