12,143 research outputs found
Heuristic-based Incremental Probabilistic Roadmap for Efficient UAV Exploration in Dynamic Environments
Autonomous exploration in dynamic environments necessitates a planner that
can proactively respond to changes and make efficient and safe decisions for
robots. Although plenty of sampling-based works have shown success in exploring
static environments, their inherent sampling randomness and limited utilization
of previous samples often result in sub-optimal exploration efficiency.
Additionally, most of these methods struggle with efficient replanning and
collision avoidance in dynamic settings. To overcome these limitations, we
propose the Heuristic-based Incremental Probabilistic Roadmap Exploration
(HIRE) planner for UAVs exploring dynamic environments. The proposed planner
adopts an incremental sampling strategy based on the probabilistic roadmap
constructed by heuristic sampling toward the unexplored region next to the free
space, defined as the heuristic frontier regions. The heuristic frontier
regions are detected by applying a lightweight vision-based method to the
different levels of the occupancy map. Moreover, our dynamic module ensures
that the planner dynamically updates roadmap information based on the
environment changes and avoids dynamic obstacles. Simulation and physical
experiments prove that our planner can efficiently and safely explore dynamic
environments
Adaptive Robotic Information Gathering via Non-Stationary Gaussian Processes
Robotic Information Gathering (RIG) is a foundational research topic that
answers how a robot (team) collects informative data to efficiently build an
accurate model of an unknown target function under robot embodiment
constraints. RIG has many applications, including but not limited to autonomous
exploration and mapping, 3D reconstruction or inspection, search and rescue,
and environmental monitoring. A RIG system relies on a probabilistic model's
prediction uncertainty to identify critical areas for informative data
collection. Gaussian Processes (GPs) with stationary kernels have been widely
adopted for spatial modeling. However, real-world spatial data is typically
non-stationary -- different locations do not have the same degree of
variability. As a result, the prediction uncertainty does not accurately reveal
prediction error, limiting the success of RIG algorithms. We propose a family
of non-stationary kernels named Attentive Kernel (AK), which is simple, robust,
and can extend any existing kernel to a non-stationary one. We evaluate the new
kernel in elevation mapping tasks, where AK provides better accuracy and
uncertainty quantification over the commonly used stationary kernels and the
leading non-stationary kernels. The improved uncertainty quantification guides
the downstream informative planner to collect more valuable data around the
high-error area, further increasing prediction accuracy. A field experiment
demonstrates that the proposed method can guide an Autonomous Surface Vehicle
(ASV) to prioritize data collection in locations with significant spatial
variations, enabling the model to characterize salient environmental features.Comment: International Journal of Robotics Research (IJRR). arXiv admin note:
text overlap with arXiv:2205.0642
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