Design And Implementation Of Task Planning And Execution System For Distributed Service Robot

Task planning and execution of distributed robots is one of the core technologies in the research field for service robots.Good scalability and functional integrity are significant development trends of task planning and execution system.Around the application demands such as carrying and delivery of the indoor service robot in distributed intelligent environment,the design and implementation of system architecture and application software for task planning and execution of distributed service robots are presented in this dissertation.The related study of task planning and execution for service robots is summarized before the difficulties and demands are analyzed.The task planning and execution system with good scalability and functional integrity for indoor service robots is designed based on the Robot Operating System(ROS)and the system operation principle is elaborated in detail.Firstly,considering the demand of logical description for working environment,the environment resource nodes are classified into three categories including intelligent sensing,intelligent execution and intelligent interaction nodes,after which the information management module is developed based on NoSQL database MongoDB,realizing the classification and storage of environment information.Besides,the logic description features of Planning Domain Definition Language(PDDL)is explained and the logic description module is developed,realizing the conversion between database information and PDDL.Secondly,considering the solution of planning problem for service robots,the Forward Chaining-Partial Order algorithm is introduced in detail and some parts are optimized,including Temporal Relaxed Planning Graph establishment,heuristic function value estimation,search space,etc,after which the corresponding node is developed to reason and generate a series of grounded actions based on the logical description of the existing environment resources.Thirdly,considering the demand of action dispatch and execution,the process of action dispatch and execution is elaborated.The action dispatch table and dispatch modes are designed,and then the typical actions deployment of intelligent nodes is given,realizing the accurate action dispatch and execution in distributed environment.Fourthly,considering the common exceptions,strategies including applied condition check,sensitive information change listening,exception handling based on transfer chain are proposed,improving the system stability.Finally,combined with typical applications for indoor service robots,the experiments of system function modules and the whole system operation for task planning and execution of distributed service robots are given by the examples of assistant carrying service and drinks delivery service,validating the correctness of system design and functions development.