Modelling and verification of a 12-DOF tractor-semitrailer longitudinal model for load transfer analysis

The analysis of the longitudinal load transfer in a tractor-semitrailer provides vital information on the magnitude of the loads transferred between the tractor unit and the semitrailer unit. This study aims to develop a tractor-semitrailer longitudinal model for load transfer analysis based on a two-axle tractor and a single-axle semitrailer connected through a fifth-wheel hitch system. The model is simulated in the MATLAB Simulink software and verified using qualitative and quantitative comparison methods between the simulation and TruckSim data through the sudden acceleration and harsh braking tests. The dynamic behaviour of the developed tractor-semitrailer model agrees well with the TruckSim dynamic behaviour with an acceptable RMS error of less than 5%. The analysis of the longitudinal load transfer found that the load transfer during the harsh braking test had higher magnitudes and longer duration of existence than the sudden acceleration test.