Hierarchical collision-free motion planning method for biped truss-climbing robots

Biped truss climbing robots (BTCRs) are employed to perform high-rise tasks within truss environments, benefiting from their superior transition capabilities and flexible mobility. However, the intricate geometry of these structures poses challenges for robot navigation and operation. To tackle this issue, this paper proposes a novel BTCRs climbing path planning framework based on a progressive multi-layer architecture. The robot’s transition regions between adjacent members are determined efficiently by unfolding three-dimensional truss members onto two-dimensional planes and discretizing them. Initially, leveraging transition analysis, a global truss member route using graph search methods is generated. Subsequently, a mathematical optimization model is introduced to determine transition grips along the global route, minimizing the total number of grips. Finally, the single-step path planner employs an improved rapidly-exploring random tree (RRT)-connect algorithm, guaranteeing collision-free motion between adjacent grips. By integrating these three layers, the framework demonstrates the feasibility and effectiveness of the proposed analysis and algorithms for climbing path planning in simulation tests, using a self-developed BTCR, Climbot.