Research on Collision Avoidance Limit of Autonomous Vehicles
Publication Name
Qiche Gongcheng/Automotive Engineering
Abstract
The precise computation of the limit collision avoidance（CA）distance for various collision avoidance control strategies is the basis for collision avoidance decision-making and control of autonomous vehicles. To clarify the impact of differential braking control on CA distance，explore the limit collision avoidance capability of steering and differential braking integrated control，and improve the calculation accuracy of the limit CA distance，in this study，a method for calculating the limit CA distance of autonomous vehicles based on nonlinear integrated vehicle dynamics and optimal control theory is proposed. Firstly，a nonlinear 7-degree-of-freedom integrated vehicle dynamics model and a Pacejka tire model with combined slip conditions are established. Subsequently，based on the established models，a limit CA distance solution problem is constructed ，which is then transformed into an optimal control problem. Next，the Gauss Pseudospectral Method（GPM）is designed to convert the optimal control problem into a nonlinear programming problem and solve it. Finally，the limit CA distances for steering control，braking control，steering and braking integrated control，and steering and differential braking integrated control are analyzed，and compared with the limit CA distances calculated based on the particle model and that tested by CarSim. The results show that the integrated control of steering and differential braking can further reduce the CA distance and significantly improve the collision avoidance capability of autonomous vehicles. The method proposed in this study can significantly improve the calculation accuracy of limit CA distance and the reliability of CA decision results.
Open Access Status
This publication is not available as open access
Volume
46
Issue
6
First Page
985
Last Page
994