VECTO programming interface for CO2 certification of HDV

Over the last few years the institute has developed the VECTO software tool for computing CO2 emissions of heavy duty vehicles. The main focus was on creating appropriate models and the simulation software itself. Calibrating the simulation models requires a lot of input data which can only be entered via the graphical user interface.

Starting in 2018 every produced HDV has to declare a CO2 value obtained from VECTO simulations. It would be cumbersome carrying out all these simulations manually via the GUI.

The VECTO programming interface (VECTO Data Exchange API – VECTO DEA) was developed at the institute. With the DEA-API VECTO can be integrated easily into applications as a software component. Hence, the input data for VECTO can be read from a database, for example, and thus the CO2 certification process can be automated.

Another application of VECTO DEA is the possibility to run model-based tests where either a single or a set of model parameters are varied. The influence of the model parameters on the simulation results can then be analysed. VECTO DEA uses VECTOs internal low-level interfaces and provides a simple to use high-level interface. VECTO DEA contains the following functionality:

  • XML-schema for VECTO jobs in declaration mode. A single XML document contains all input data required for the simulation.
  • XML-schema for VECTO components (e.g., engine, gearbox, axle gear, etc.). The XML documents of individual components together with vehicle parameters build a VECTO job.
  • XML-schema for VECTO jobs and components in engineering mode. In engineering mode a job can be either a single XML document containing all input data or reference further XML documents for component data and loss-maps.
  • Allows using XML-based jobs in the graphical user interface.
  • Export VECTO jobs as XML documents.
  • Run multiple VECTO simulations in parallel.

Internally the VECTO DEA has already been used for another project, which aimed at the elaboration of the time series of the specific fuel consumption values from trucks and buses as basis for a possible future CO2 related highway charges. The figure below shows as example the results for 40t tractor trailer combinations in comparison to other sources from literature. Fully reliable reference values for the past do not exist. Thus it is open yet which values match the reality best.

Development of the specific fuel consumption values from 40t tractor trailer combinations, different sources (L&A: Magazin Lastauto und Omnibus; VR: Magazin Verkehrsrundschau; CNR: Comité National Routier; Daimler: Veröffentlichung 2016; VECTO BMVI: Simulation with VECTO at the Institute)