Obstacle avoidance in a dynamic environment: a collision cone approach

TLDR

The method imposes no restrictions on the shapes of the robot or obstacle, allowing arbitrary geometries. The study proposes a collision‑cone approach to aid collision detection and avoidance between irregularly shaped moving objects with unknown trajectories. The collision‑cone concept is built incrementally from point‑to‑point collision predictions, extended to point‑circle, point‑irregular, circle‑circle, and irregular‑irregular cases, and used to generate avoidance strategies while discussing shape approximations to reduce computational load. The collision cone effectively predicts imminent collisions between a robot and a moving obstacle, as demonstrated by illustrative examples of collision prediction and avoidance strategies.

Abstract

A novel collision cone approach is proposed as an aid to collision detection and avoidance between irregularly shaped moving objects with unknown trajectories. It is shown that the collision cone can be effectively used to determine whether collision between a robot and an obstacle (both moving in a dynamic environment) is imminent. No restrictions are placed on the shapes of either the robot or the obstacle, i.e., they can both be of any arbitrary shape. The collision cone concept is developed in a phased manner starting from existing analytical results that enable prediction of collision between two moving point objects. These results are extended to predict collision between a point and a circular object, between a point and an irregularly shaped object, between two circular objects, and finally between two irregularly shaped objects. Using the collision cone approach, several strategies that the robot can follow in order to avoid collision, are presented. A discussion on how the shapes of the robot and obstacles can be approximated in order to reduce computational burden is also presented. A number of examples are given to illustrate both collision prediction and avoidance strategies of the robot.