# Real-Time Trajectory Replanning for MAVs using Uniform B-splines and a 3D Circular Buffer

## TL;DR

This paper introduces a real-time local trajectory replanning method for MAVs that handles dynamic obstacles using a 3D circular buffer and uniform B-splines, enabling smooth and efficient trajectory updates in cluttered environments.

## Contribution

It presents a novel real-time replanning algorithm that extends static environment planners to dynamic scenarios using a moving occupancy grid and B-spline trajectories.

## Key findings

- Successfully handles unmodeled and dynamic obstacles in real-time
- Maintains MAV proximity to global trajectory during replanning
- Ensures smooth and computationally efficient trajectory updates

## Abstract

In this paper, we present a real-time approach to local trajectory replanning for microaerial vehicles (MAVs). Current trajectory generation methods for multicopters achieve high success rates in cluttered environments, but assume that the environment is static and require prior knowledge of the map. In the presented study, we use the results of such planners and extend them with a local replanning algorithm that can handle unmodeled (possibly dynamic) obstacles while keeping the MAV close to the global trajectory. To ensure that the proposed approach is real-time capable, we maintain information about the environment around the MAV in an occupancy grid stored in a three-dimensional circular buffer, which moves together with a drone, and represent the trajectories by using uniform B-splines. This representation ensures that the trajectory is sufficiently smooth and simultaneously allows for efficient optimization.