Collision risk reduction of N-trailer agricultural machinery by off-track minimization

In this work we study the effect of changing the vehicle guidance point position over the collision risk and motion control performance of an N-trailer vehicle. Based on a Monte Carlo method, we are able to find the correlation among motion control performance, trajectory curvature variation and guidance point position, to strategically select the latter to enhance the motion control performance. The performance metrics consider controller effort and manoeuvrability space penalties associated with off-track errors and unsafe manoeuvres of the entire vehicles’ chain. To validate scalability of the guidance point selection strategy, several N-trailer vehicles were tested in simulation to track a trajectory with abrupt curvature changes, similar to the trajectories executed by machinery in agricultural operations. The performance results are compared to ones obtained using traditional strategy to show the reduction of dangerous manoeuvres as internal turning from 24.5% up to 42.6% as well as a reduction of the resultant off-track errors from 17.3% up to 26.84% in the cases from 4 to 10 trailers respectively.