Efficient collision avoidance for autonomous vehicles in polygonal domains

TL;DR

This paper introduces three novel, efficient formulations for collision avoidance in autonomous vehicle trajectory planning, reducing computational complexity and demonstrating effectiveness in parking scenarios.

Contribution

The study presents three new exact collision constraint formulations based on convex set separation, improving computational efficiency in autonomous vehicle trajectory optimization.

Findings

Hyperplane separation theorem formulations reduce computational resources.

De Morgan's laws-based formulation performs comparably to dual formulations.

Proposed methods outperform existing approaches in typical parking scenarios.

Abstract

This research focuses on trajectory planning problems for autonomous vehicles utilizing numerical optimal control techniques. The study reformulates the constrained optimization problem into a nonlinear programming problem, incorporating explicit collision avoidance constraints. We present three novel, exact formulations to describe collision constraints. The first formulation is derived from a proposition concerning the separation of a point and a convex set. We prove the separating proposition through De Morgan's laws. Then, leveraging the hyperplane separation theorem we propose two efficient reformulations. Compared with the existing dual formulations and the first formulation, they significantly reduce the number of auxiliary variables to be optimized and inequality constraints within the nonlinear programming problem. Finally, the efficacy of the proposed formulations is demonstrated in the context of typical autonomous parking scenarios compared with state of the art. For generality, we design three initial guesses to assess the computational effort required for convergence to solutions when using the different collision formulations. The results illustrate that the scheme employing De Morgan's laws performs equally well with those utilizing dual formulations, while the other two schemes based on hyperplane separation theorem exhibit the added benefit of requiring lower computational resources.