Diagonal node-based path planning and path smoothing for first responders and rescue Robots

A key point of reducing injury rates for first responders is spending less time to reach a target in a dangerous area. First responders and rescue robots are applied in previous researches using dangerous areas search and obstacle avoidance. Unmanned aerial vehicles (UAVs) are also started to use for disaster management. Therefore, path planning for the first responders and rescue robots are needed the during dangerous area searching using UAVs. Here, path planning algorithms for the first responders and rescue robots are needed to global path planning and it is better to use different kinds of node-based algorithms depending on a known and a partially known environment. An A* algorithm is suitable in the known environment and a D* lite algorithm is proper in the partially known environment. However, long path calculation time is always an issue of the node-based global path planning. For the long path calculation time, a novel diagonal path planning algorithm is proposed in this paper. The main idea of the diagonal path planning is to use diagonal nodes instead of surrounded nodes from current node selection steps. Also, it causes a zig-zag path issue, so a path smoothing with a bounded curvature is proposed to solve the zig-zag issue. The effectiveness of the proposed algorithm is confirmed through simulations.