A Dyno Data Acquisition System for Lean NOx Trap Investigations

A flexible, easily configuration data acquisition system was designed and built for detailed studies of the steady state and dynamic properties of lean NOx traps for an engine dynamometer environment. The system is based on the industry standard VXI backplane. The overriding design philosophy was to design and develop a data acquisition system that was user friendly and could be operated easily by engine laboratory technicians, as well as by test engineers. The primary requirements guiding the design were the following: (1) the ability easily to configure, save, recall, modify, and print test configurations. (2) The ability to configure the gain, channel name, and engineering units for each analog channel. (3) The ability to trigger from one analog input channel. (4) A provision for numeric auto-incrementing of data file names. (5) The ability to save data in Excel™ compatible ASCII format. (6) The utilization of off-the shelf VXI hardware. The primary user interface display is written in Labview™. It includes the real time displays and the primary control display. The Test Manager™ software is written in C++, and provided the interface to manage tests and store test configurations. The Test Manager™ is modeled after Windows Explorer™ and has the capability to create, copy, save, and modify tests; set trigger conditions; and define other test parameters. The application of this novel data acquisition system to the study and characterization of lean NOx traps is briefly discussed.