Research On Path Planning Of Ground Unmanned Combat Platform Based On Environmental Information And Kinematic Constraints

With the development of intelligent technology,the technology of unmanned combat platform is constantly improving.Four-wheel drive unmanned combat platform has the characteristics of fast speed,flexible steering and high work efficiency.It has been widely used in military,industrial,earthquake relief and other field environments.Among them,the path planning of four-wheel drive unmanned combat platform has always been a hot issue.However,there is relatively little research on the existing path planning algorithm for four-wheel drive unmanned combat platform,and the constraints of unmanned platform in environmental information and kinematics are not considered.The standard A* algorithm has some problems in the path planning of unmanned platform,such as long time,path redundancy and unevenness caused by more turning points.This paper takes the four-wheel drive unmanned combat platform as the research object,carries out kinematic modeling and analysis for the four-wheel drive combat platform,studies and analyzes the path planning algorithm from two aspects of environmental information and kinematic constraints,and puts forward an improved path planning method of unmanned combat platform.The main work of this paper is as follows:(1)Firstly,the basic structure,principle and motion characteristics of the ground unmanned combat platform are studied and analyzed.The motion model of the four-wheel drive combat platform is simplified into a two-wheel drive motion model.Finally,the kinematics modeling of the ground unmanned combat platform is carried out on the basis of the simplified motion model.Based on this modeling method,the complexity of the path planning algorithm can be greatly simplified,and effectively ensure the movement safety of the combat platform in the real environment.(2)Secondly,based on the environmental information and node search,the standard A*algorithm is improved,the path is smoothed by combining the Floyd algorithm with kinematic constraints,and the improved A* algorithm is used to plan the global path of the ground unmanned combat platform.This method improves the cost function through the weight coefficient of obstacles in the environment map.The search node of the algorithm is more directional,which improves the efficiency of the algorithm and ensures the real-time performance of the algorithm;At the same time,this method considers the constraints such as the motion characteristics and safety distance of the ground unmanned combat platform in the process of path optimization to ensure the motion safety of the ground unmanned combat platform.The improved A* algorithm always keeps a certain distance from obstacles in path planning,and the search nodes and path planning time are reduced;The path planning integrating motion characteristics is smoother and the path angle is smaller,which is more conducive to the movement of the ground unmanned combat platform.(3)Thirdly,according to the requirements of local path planning of unmanned combat platform,Dynamic window algorithm(DWA)is introduced to improve the algorithm path evaluation function,design the dynamic window algorithm of adaptive evaluation function,and integrate with the global path planning of improved A* algorithm.Combining the improved A*algorithm and the dynamic window algorithm,the local path planning is carried out on the basis of the global path,which avoids too many redundant paths,effectively shortens the movement time,avoids unknown obstacles in time,and realizes the path security of the ground unmanned combat platform.(4)Finally,the experimental platform WHEELTEC＿CAR four-wheel drive unmanned platform is the research object.Experiments on the path planning method of unmanned combat platform mentioned above under different actual environment scenarios are carried out to verify the feasibility and effectiveness of the global path planning method of unmanned combat platform in known environment and the local path planning method of unmanned combat platform in unknown environment.The experimental results show that the path planning method combining the improved A* algorithm and DWA algorithm with the shortest travel time as the optimization goal is better than the typical path planning method,whether the environmental information is known or unknown,and can better guide the collision free optimization task of unmanned combat platform in the obstacle environment.In short,this paper takes the ground unmanned combat platform as the research object,analyzes the kinematic model of the four-wheel drive combat platform,improves the path planning algorithm from two aspects: the global path planning of the known environment and the local path planning of the unknown environment,and puts forward an improved path planning method of the ground unmanned combat platform.Relevant research results will further enrich the research content of path planning,and provide some theoretical basis and technical support for the automatic driving and control of unmanned vehicles in the project.