Hybrid Path Planning For Mobile Robot Based On Firefly Algorithm And Dynamic Window Approach

Autonomous navigation is the key technology of mobile robot,path planning is the important part of autonomous navigation research field.The path planning of mobile robot is usually divided into global path planning based on known environmental information and local path planning based on sensor sensing environment information.The environment often changes in the application scene of mobile robot,and it is not ideal to use global path planning or local path planning alone.In this regard,this paper combines the global path planning and local path planning closely to make full use of the known environmental information and respond to the environment changes to optimize the path planning effect.The main research contents include:(1)The global path planning based on improved firefly algorithm,global path is evaluated synthetically and firefly algorithm is improved,the global path and the alternative path are generated,and the target point of the local path planning is provided.Firstly,the grid method is used to model the environment,then the path length,the path smoothness and the path safety are considered in the target function of the firefly algorithm.In view of the shortcoming that the firefly algorithm is easy to converge early and fall into the local optimal,the relative luminance,adaptive change of step length,brightest firefly constraint and multi group communication mechanism are introduced to improve the standard firefly algorithm combined with the application background of the path planning.Improved firefly algorithm is used for global path planning to pre-generate multiple paths in order to switch path necessarily when environment changes.The turning point of global path is regarded as the target point for local path planning.(2)The local path planning based on fuzzy dynamic window approach takes into account the dynamic performance of the robot and improves the adaptability of the mobile robot to various complex environments.First,the distance of target point is introduced in the evaluation function of dynamic window approach to improve the speed control effect when the robot is near the target point.Then the fuzzy reasoning method is used to dynamically adjust the weight coefficient of each part of the evaluation function and optimize the local path planning.(3)The hybrid algorithm based on improved firefly algorithm and fuzzy dynamic window approach,the path switching method and hierarchical planning method of hybrid path planning are given.In this hybrid path planning,the robot carries out the local path planning along the global path.When the environment changes,the robot can avoid obstacle in real time.If the real-time obstacle avoidance fails,the path is switched that the alternative path is used as the current global path to improve the real-time performance of the path planning,and then the new global path continues to guide the robot to reach the global target point.The simulation experiment of hybrid path planning was designed on the MATLAB platform,and a mobile robot experimental platform was built.The effectiveness of the hybrid path method proposed in this paper was verified by simulation experiments and physical experiments.