To solve the problems in the application of RRT* algorithm in the process of obstacle avoidance motion planning for multi-DOF manipulators in 3D space

including low planning efficiency

large memory consumption and unstable planning result

a heuristic dynamic constrained sampling RRT* algorithm(HDCS-RRT*) is proposed in this paper. The algorithm devises a strategy of heuristic dynamic sampling domain

introduces the idea of goal-biased approach towards bounded to improve the convergence speed; it develops an adaptive node generation mechanism to adjust the generation mode of new nodes according to the obstacle environment

improves the stability of the algorithm; and the path costs are further optimized through redundant point detection. Simulation and experimental results show that the improved algorithm has faster planning

good adaptability in narrow areas

and can generate better motion paths with lower memory consumption and shorter path planning time than the RRT* algorithm.