Visibility Graph Approach to Detailed Path Planning in CNC Concrete Placement

An algorithm that employs visibility graph approach to generate a minimal L¬¬1-metric obstacle avoidance path in CNC concrete placement is presented. A set of pseudo-obstacles that represent nodes in a relational structure called Rectangle Adjacency Graph (RAG) is introduced during construction of visibility graph. Shrinking of pseudo-obstacles and growing of primary obstacles such as elevator shafts results in an efficient network for generating minimal L1-metric paths from a given source location to target location in concrete floors. Secondary obstacles such as column bars are avoided using geometric and topological relationships stored in the RAG.