In complex factory environments with multiple obstacles, in order to solve the problem that the path generated by rapidlyexploring random tree star algorithm(RRT*) has redundant points, is close to the obstacle and has jagged turns, the path planning algorithm of SSRRT*［Safe-Smooth RRT*］ is improved. Firstly, a target biasing strategy is introduced. Secondly, the algorithm utilizes a new node expansion approach that combines the concept of target point attraction and an improved nearest neighbor point metric to reduce the blind expansion of the tree and accelerate growth towards the target point; Node security constraints are then imposed to add the security nodes to the tree; Improved path simplification eliminates redundant points while taking into account security; Finally, the local smoothing of the B-spline is used to improve the smoothness of the path. By comparing with the standard RRT* algorithm, the adaptive target bias RRT algorithm, and improved RRT algorithm，the maximum decrease in average path length is 7.1%, the maximum decrease in average effective node number is 64.1%, and always keep a safe distance from obstacles. The results indicate that the improved algorithm effectively improves the smoothness and safety of the path.