An autonomous underwater vehicle (AUV) must use an algorithm to plan its path to distant, mobile offshore objects. Because of the uneven distribution of obstacles in the real world, the efficiency of the algorithm dec...An autonomous underwater vehicle (AUV) must use an algorithm to plan its path to distant, mobile offshore objects. Because of the uneven distribution of obstacles in the real world, the efficiency of the algorithm decreases if the global environment is represented by regular grids with all of them at the highest resolution. The framed quadtree data structure is able to more efficiently represent the environment. When planning the path, the dynamic object is expressed instead as several static objects which are used by the path planner to update the path. By taking account of the characteristics of the framed quadtree, objects can be projected on the frame nodes to increase the precision of the path. Analysis and simulations showed the proposed planner could increase efficiency while improving the ability of the AUV to follow an object.展开更多
A wireless communication method with dynamic adding nodes for Underground Search and Rescue robot is proposed： fix the address of the controller, add repeater nodes into the net dynamically, and shift the address of ...A wireless communication method with dynamic adding nodes for Underground Search and Rescue robot is proposed： fix the address of the controller, add repeater nodes into the net dynamically, and shift the address of the mobile terminal. With this method, the Search and Rescue robot can reach the deeper place of a mine to help rescue and keep in touch with the controller through wireless communication in a single channel, even in a complex laneway where radio wave cannot go through the thick wall. The collision in the process of the two-way multi-hop communication in the single channel will also be resolved by the communication direction priority and response signal mechanism, to enhance the reliability of communication. Finally, a sample is designed and an experiment is conducted to verify the efficiency of the method.展开更多
The paper explores applications of genetic programming to co-evolution of morphology and low-level control. In most reasonably difficult tasks, facilitation provided by modularity has proved to be vital for successful...The paper explores applications of genetic programming to co-evolution of morphology and low-level control. In most reasonably difficult tasks, facilitation provided by modularity has proved to be vital for successful application of genetic programming. However, the need for sharing data among nodes in the syntactic tree becomes especially acute when evolving modular programs. It has been shown before that it may be beneficial that modules themselves be node-attached. The paper presents extensions to standard genetic programming （the so-called contexts and context blocks） that allow for straight-forward storage, retrieval, transfer, and modification of data stored in the context of a syntactic tree, and shared by multiple nodes. Framework is thus provided for both： data sharing and node-attached modules. Finally, using context blocks, a genetic algorithm has been embedded within genetic programming to evolve values of constants. In genetic programming evolution of constants has been a long-standing problem. The paper shows how context blocks can be utilized to provide a more granular and flexible approach to their evolution. As shown in previous works, node-attached modules perform favorably when compared with existing approaches. Concerning evolution of context block constants, it is shown here that they too perform favorably when compared with ephemeral constants.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No. 60875071
文摘An autonomous underwater vehicle (AUV) must use an algorithm to plan its path to distant, mobile offshore objects. Because of the uneven distribution of obstacles in the real world, the efficiency of the algorithm decreases if the global environment is represented by regular grids with all of them at the highest resolution. The framed quadtree data structure is able to more efficiently represent the environment. When planning the path, the dynamic object is expressed instead as several static objects which are used by the path planner to update the path. By taking account of the characteristics of the framed quadtree, objects can be projected on the frame nodes to increase the precision of the path. Analysis and simulations showed the proposed planner could increase efficiency while improving the ability of the AUV to follow an object.
基金supported by State Key Laboratory of Robotics and System of Harbin Institute of Technology(SKLRS-2009-MS-03)
文摘A wireless communication method with dynamic adding nodes for Underground Search and Rescue robot is proposed： fix the address of the controller, add repeater nodes into the net dynamically, and shift the address of the mobile terminal. With this method, the Search and Rescue robot can reach the deeper place of a mine to help rescue and keep in touch with the controller through wireless communication in a single channel, even in a complex laneway where radio wave cannot go through the thick wall. The collision in the process of the two-way multi-hop communication in the single channel will also be resolved by the communication direction priority and response signal mechanism, to enhance the reliability of communication. Finally, a sample is designed and an experiment is conducted to verify the efficiency of the method.
文摘The paper explores applications of genetic programming to co-evolution of morphology and low-level control. In most reasonably difficult tasks, facilitation provided by modularity has proved to be vital for successful application of genetic programming. However, the need for sharing data among nodes in the syntactic tree becomes especially acute when evolving modular programs. It has been shown before that it may be beneficial that modules themselves be node-attached. The paper presents extensions to standard genetic programming （the so-called contexts and context blocks） that allow for straight-forward storage, retrieval, transfer, and modification of data stored in the context of a syntactic tree, and shared by multiple nodes. Framework is thus provided for both： data sharing and node-attached modules. Finally, using context blocks, a genetic algorithm has been embedded within genetic programming to evolve values of constants. In genetic programming evolution of constants has been a long-standing problem. The paper shows how context blocks can be utilized to provide a more granular and flexible approach to their evolution. As shown in previous works, node-attached modules perform favorably when compared with existing approaches. Concerning evolution of context block constants, it is shown here that they too perform favorably when compared with ephemeral constants.
