In this paper, we consider the problem of exploring unknown environment with an intelligent virtual agent. Traditionally research efforts to address the exploration and mapping problem have focused on the graph-based space representations and the graph search algorithms. In this paper, we propose DFS-RTA* and DFS-PHA*, two real-time graph search algorithms for exploring and mapping an unknown environment. Both algorithms are based upon the simple depth-first search strategy. However, they adopt different real-time shortest path-finding methods for fast backtracking to the last unexhausted node. Through some experiments with a virtual agent deploying in a 3D interactive computer game environment, we confirm the completeness and efficiency of two algorithms.


Unknown Environment Virtual Agent Individual Exploration Exploration Algorithm Graph Search Algorithm 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • In-Cheol Kim
    • 1
  1. 1.Department of Computer ScienceKyonggi UniversitySouth Korea

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