An instrumentation system for gathering information pertinent to the performance of an adaptive cruise control system

The data acquisition system (DAS) installed in the ACC-equipped vehicles is designed to collect, process, and store both numerical and video data files using two on-board computers to quantify aspects of the driving process that are pertinent to the control of speed and clearance gap relative to the closest preceding vehicle. The data are collected and stored on a trip-per-trip basis. Once a trip is completed an on-board computer sends summary data via cellular phone to a server at the base station. These data are mainly in the form of histograms and trip summary numerics computed online to describe features of the trip. After 2 to 5 weeks in typical transportation service in the field operational test (FOT), the ACC vehicles are returned to the base station and time histories of pertinent variables such as range, range-rate, and velocity plus GPS and video data are downloaded. This paper describes how and why the DAS does what it does.