2 research outputs found
Graph Neural Networks for Motion Planning
This paper investigates the feasibility of using Graph Neural Networks (GNNs)
for classical motion planning problems. We propose guiding both continuous and
discrete planning algorithms using GNNs' ability to robustly encode the
topology of the planning space using a property called permutation invariance.
We present two techniques, GNNs over dense fixed graphs for low-dimensional
problems and sampling-based GNNs for high-dimensional problems. We examine the
ability of a GNN to tackle planning problems such as identifying critical nodes
or learning the sampling distribution in Rapidly-exploring Random Trees (RRT).
Experiments with critical sampling, a pendulum and a six DoF robot arm show
GNNs improve on traditional analytic methods as well as learning approaches
using fully-connected or convolutional neural networks
Guided Incremental Local Densification for Accelerated Sampling-based Motion Planning
Sampling-based motion planners rely on incremental densification to discover
progressively shorter paths. After computing feasible path between start
and goal , the Informed Set (IS) prunes the configuration space
by conservatively eliminating points that cannot yield shorter
paths. Densification via sampling from this Informed Set retains asymptotic
optimality of sampling from the entire configuration space. For path length
and Euclidean heuristic , .
Relying on the heuristic can render the IS especially conservative in high
dimensions or complex environments. Furthermore, the IS only shrinks when
shorter paths are discovered. Thus, the computational effort from each
iteration of densification and planning is wasted if it fails to yield a
shorter path, despite improving the cost-to-come for vertices in the search
tree. Our key insight is that even in such a failure, shorter paths to vertices
in the search tree (rather than just the goal) can immediately improve the
planner's sampling strategy. Guided Incremental Local Densification (GuILD)
leverages this information to sample from Local Subsets of the IS. We show that
GuILD significantly outperforms uniform sampling of the Informed Set in
simulated , environments and manipulation tasks in
.Comment: Submitted to IROS 202