Description of the development of the LabVIEW instantaneous emissions estimation software for use in the urban environment project air quality work package

This Working Paper describes the development of the current LabVIEW software programme used to extract On-Board Diagnostic (OBD) signals from vehicles. LabVIEW is a graphical programming language based on G-coding [3] and provides a simple environment for data collection and display. The current software version (Version 2.1) receives inputs from the vehicle via the OBD connector and displays the parsed and manipulated values of engine load, engine speed, coolant temperature and vehicle speed on a purpose built graphical user interface. Table 1 describes the various versions of the software package and explains which parameters were used in each one, such that the current working version was achieved. The purpose of this document is to outline the processes involved in achieving this system and to describe its use in service.