Efficient Path Interpolation and Speed Profile Computation for Nonholonomic Mobile Robots

TL;DR

This paper presents a simple, real-time capable method for interpolating paths and computing speed profiles for nonholonomic robots, ensuring smooth, obstacle-clear paths with bounded curvature and efficient speed optimization.

Contribution

It introduces a low-complexity, real-time path interpolation method and a linear-time speed profile algorithm that handle broader physical constraints than existing solutions.

Findings

Path interpolation produces smooth, obstacle-clear paths with bounded curvature.

Speed profile algorithm computes time-optimal speeds in linear time.

Methods are validated in Eurobot contest scenarios.

Abstract

This paper studies path synthesis for nonholonomic mobile robots moving in two-dimensional space. We first address the problem of interpolating paths expressed as sequences of straight line segments, such as those produced by some planning algorithms, into smooth curves that can be followed without stopping. Our solution has the advantage of being simpler than other existing approaches, and has a low computational cost that allows a real-time implementation. It produces discretized paths on which curvature and variation of curvature are bounded at all points, and preserves obstacle clearance. Then, we consider the problem of computing a time-optimal speed profile for such paths. We introduce an algorithm that solves this problem in linear time, and that is able to take into account a broader class of physical constraints than other solutions. Our contributions have been implemented and evaluated in the framework of the Eurobot contest.