Safe Interval Path Planning With Kinodynamic Constraints
This work addresses path planning for mobile robots with realistic motion constraints, making it incremental by extending SIPP to handle kinodynamic limitations.
The authors tackled the problem of Safe Interval Path Planning (SIPP) being incomplete under kinodynamic constraints, such as acceleration and deceleration, by introducing a novel variant that is provably complete and optimal. They showed that this modified SIPP performs much less expansions than A* and is notably faster in experiments.
Safe Interval Path Planning (SIPP) is a powerful algorithm for solving single-agent pathfinding problem when the agent is confined to a graph and certain vertices/edges of this graph are blocked at certain time intervals due to dynamic obstacles that populate the environment. Original SIPP algorithm relies on the assumption that the agent is able to stop instantaneously. However, this assumption often does not hold in practice, e.g. a mobile robot moving with a cruising speed is not able to stop immediately but rather requires gradual deceleration to a full stop that takes time. In other words, the robot is subject to kinodynamic constraints. Unfortunately, as we show in this work, in such a case original SIPP is incomplete. To this end, we introduce a novel variant of SIPP that is provably complete and optimal for planning with acceleration/deceleration. In the experimental evaluation we show that the key property of the original SIPP still holds for the modified version -- it performs much less expansions compared to A* and, as a result, is notably faster.