Path Planning Using Optimal Path Search Algorithms and Smoothing for Polymer Soft Robots in a Static Environment
Subject Areas : سامانه های پلیمری تحریک پذیر
Ali Esmailli
1
,
Mohammad Hossein Khalesi
2
,
Mohammadreza Doostmohammadian
3
1 - Semnan University
2 - Semnan University
3 - Semnan University
Keywords: Polymer soft robot, path planning algorithm, path smoothing, static environment,
Abstract :
Polymer soft robots with flexible bodies require smooth paths with continuous curvature for safe navigation. However, classical path planning algorithms such as Dijkstra and A* generate only the shortest path with sharp turns, which is incompatible with the kinematics of these robots. In this study, a path smoothing method is proposed by replacing right-angle corners with circular arcs of variable radius, and evaluated in grid environments with 250 to 1000 random obstacles. Sensitivity analysis shows that increasing obstacle density drastically raises the percentage of path length increase; for instance, in the 1000-obstacle scenario, the path length increases by up to 23% for a radius of 4 meters. The bending efficiency ratio decreases from 90% at a radius of 0.5 m to 20% at 4 m, while the efficiency ratio maintains double-digit values for radii smaller than one meter across all scenarios. Moreover, the average safe distance from obstacles remains around 17 meters in the worst case. Computationally, the A* algorithm performs significantly faster than Dijkstra. The findings provide a quantitative framework for selecting the bending radius according to the requirements of polymer soft robots. This approach can serve as a basis for real‑time path design for polymer soft robots in static, highly cluttered environments.
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