Driving Stability of Closed Loop Tractor-Semitrailer Vehicle System with Optimal Driver Model

A quasi-linear driver model was developed, and a closed loop tractor-semitrailer vehicle system composed of the driver model and a tractor-semitrailer vehicle model of 3-degrees-of-freedom were proposed. The stability of closed loop vehicle system was studied by simulating the system with different parameter values. A roots-locating numerical method was used to identify critical speed of the system. Some simulation of closed loop vehicle system were made in Matlab and the results shown that driver´s inherent time delay, a semitrailer´s load and driving speed make important role in stability of closed loop tractor-semi trailer.