Submitted: November 2018


In September 2017 the European Union replaced the old type approval procedure for cars called NEDC with the new WLTP. The new procedure aims to improve — among other things — the CO2 emission estimation for the car by introducing a new driving cycle WTLC. With the objective of simplifying the introduction of WLTP, a correlation software called CO2MPAS was developed to translate the new procedure’s CO2 results into the old test results without physically driving the test. The software back-translates the average CO2 emissions measured in the new test to the old values by simulating the old test with a number of measurements done while performing the new test procedure. The software has a direct effect on the enforcement of currently active EU regulations that aim to limit CO2 emissions. We investigated, how this software works. In a first step, the underlying framework of CO2MPAS — Schedula — was analysed via testing and study of the documentation and source code. From this, a theoretical foundation for the framework was developed to allow deeper investigations of programs written in Schedula. In a second step, the gained knowledge was used to manually inspect the Schedula model of the car simulation in CO2MPAS. The size of this model does not allow for exhaustive analysis, however this work provides some insight into some key elements of the computation.