关键词: 柔性针, 路径规划, 环境特征, 快速搜索随机树

Abstract: Aiming at the problem of the path planning for flexible needle insertion into soft tissue, the planning algorithm based on environment properties and random method is proposed. In this method, the unicycle model is adopted, and the sample paths are planned using the Rapidly-exploring Random Tree algorithm. Then the optimal path is selected by the path evaluation function. The function is composed of normalized sub-functions relating to the path length, the number of arcs, the safety degree and the risk grade of obstacles. For different environments and applications, the weight coefficient of each sub-function and the risk level of each obstacle can be adjusted according to surgeon’s clinical experience. Finally, the simulation of the path planning for flexible needle is performed in complicated environments. The results show that the proposed method has better environmental adaptability and provides more interaction, and then has potential for practical application.

Key words: flexible needle, path planning, environment properties, rapidly-exploring random tree