Longitudinal control of heavy-duty vehicles for automated highway systems

We address the problem of longitudinal control design for the automated operation of heavy-duty vehicles. We present a longitudinal model of a heavy-duty truck equipped with a turbocharged intercooled diesel engine and a four speed automatic transmission. This model is built at a level of detail suitable for control design and is used to develop and compare, on the basis of simulation results, nonlinear controllers with fixed as well as adaptive gains for speed tracking. Then we turn our attention to the vehicle-following problem, in which an important control objective is string stability of closely spaced groups of vehicles (platoons). We design an adaptive nonlinear controller which generates both fuel and brake commands and yields string stability by using either a speed-dependent spacing policy or intervehicle communication.