Online State-Time Trajectory Planning Using Timed-ESDF in Highly Dynamic Environments

10/29/2020
by   Delong Zhu, et al.
0

Online state-time trajectory planning in highly dynamic environments remains an unsolved problem due to the unpredictable motions of moving obstacles and the curse of dimensionality from the state-time space. Existing state-time planners are typically implemented based on randomized sampling approaches or path searching on discretized state graph. The smoothness, path clearance, and planning efficiency of these planners are usually not satisfying. In this work, we propose a gradient-based planner over the state-time space for online trajectory generation in highly dynamic environments. To enable the gradient-based optimization, we propose a Timed-ESDT that supports distance and gradient queries with state-time keys. Based on the Timed-ESDT, we also define a smooth prior and an obstacle likelihood function that is compatible with the state-time space. The trajectory planning is then formulated to a MAP problem and solved by an efficient numerical optimizer. Moreover, to improve the optimality of the planner, we also define a state-time graph and then conduct path searching on it to find a better initialization for the optimizer. By integrating the graph searching, the planning quality is significantly improved. Experiment results on simulated and benchmark datasets show that our planner can outperform the state-of-the-art methods, demonstrating its significant advantages over the traditional ones.

READ FULL TEXT

page 5

page 6

page 7

page 8

11/07/2020

Search-Based Online Trajectory Planning for Car-like Robots in Highly Dynamic Environments

This paper presents a search-based partial motion planner to generate dy...
08/20/2020

EGO-Planner: An ESDF-free Gradient-based Local Planner for Quadrotors

Gradient-based planners are widely used for quadrotor local planning, in...
08/08/2020

TGK-Planner: An Efficient Topology Guided Kinodynamic Planner for Autonomous Quadrotors

In this paper, we propose a lightweight yet effective quadrotor planning...
10/20/2021

A Fast Planning Approach for 3D Short Trajectory with a Parallel Framework

For real applications of unmanned aerial vehicles, the capability of nav...
01/31/2022

G^2VD Planner: An Efficient Motion Planning Approach With Grid-based Generalized Voronoi Diagrams

In this letter, an efficient motion planning approach with grid-based ge...
12/29/2019

Robust Real-time UAV Replanning Using Guided Gradient-based Optimization and Topological Paths

Gradient-based trajectory optimization (GTO) has gained wide popularity ...
09/27/2019

TORM: Collision-Free Trajectory Optimization of Redundant Manipulator given an End-Effector Path

A redundant manipulator has multiple inverse kinematics solutions per an...