D* Lite Based Real-Time Multi-Agent Path Planning in Dynamic Environments

Abstract

D* based navigation algorithms provide robust and realtime means of achieving path planning in dynamic environments. Author of this paper introduces a notion of predictable time-based obstacles. The algorithm proposed in the paper defines a centralized obstacle-map that is shared among multiple agents (robots) performing path planning. Each robot plans its path individually on an obstacle-map using a slightly modified version of D* Lite and then shares an updated version of the map, which includes its planned path as a new obstacle, with its peers. The planned paths appear as temporary time-based obstacles to peer robots. Planned paths are divided into discrete temporal sections so as to help peer robots optimize paths temporally. The proposed algorithm also presents a priority measure which helps us decide the optimized sequence of individual pathplanning order followed by cooperating robots. Since the implemented algorithm is tested in simulation using Mobile robot Programming Toolkit, the Real–time performance analysis is done to confirm the real-time execution time of the proposed algorithm. Keywordsrobotics; path-planning; D*; navigation; multi-