基于人工势场与速度合成的AUV路径规划

水下环境与地面环境有着本质区别,海流对自治水下机器人航行的影响远大于地面移动机器人所受风速的影响,因此,AUV(Autonomous Underwater Vehicle)水下作业的过程中,不仅要避开运动过程中所遇到的障碍物,还要考虑受到海流因素的影响.将人工势场路径规划算法直接应用到AUV路径规划中,显然难以达到路径最优效果.为解决AUV在海流环境下的路径规划问题,本文针对机器人水下航行的特点,在传统人工势场方法的基础上,考虑海流作用,将速度合成的算法与人工势场相结合,克服海流对AUV水下航行的影响,提出一种新的AUV水下路径规划算法.仿真试验表明,所提算法达到了良好的效果.     

不确定海流环境下水下机器人最优时间路径规划

为解决海流预测不精确条件下,现有基于确定性海流路径规划算法鲁棒性差和规划的路径有可能为不可行路径的问题,本文提出一种基于区间优化的水下机器人(AUV)最优时间路径规划算法.该算法采用双层架构,外层用蚁群系统算法(ACS)寻找由起点至终点的候选路径;内层以区间海流为环境模型,计算候选路径航行时间上下限,并分别通过区间序关系和基于可靠性的区间可能度模型将航行时间区间转换为确定性评价函数,并将评价函数值作为候选路径适应度值返回到外层算法.仿真结果表明,相对于确定海流场路径规划方案,提出的方案增强了路径规划器的鲁棒性并解决了结果路径不可行问题.     

基于前视声纳信息的AUV局部路径规划研究

针对水下环境的不确定性,建立了前视声纳的视域模型。主要采用强化学习的方法对自治水下机器人(AUV)进行控制和决策,综合Q学习算法、BP神经网络法、人工势场法对AUV进行局部路径规划。在AUV与环境的试错交互中,借助于来自成功与失败经验的奖励和惩罚值,不断改进水下机器人的自治能力。并设计了AUV局部路径规划器,实现AUV在不确定环境下的避障任务。半实物仿真证明了算法的可行性与可靠性。     

基于蚁群模拟退火算法的水下机器人路径规划

全局路径规划是水下机器人(AUV)研究领域的重要课题之一,文中研究已知障碍物环境条件下的水下机器人路径规划问题;提出一种分布路径规划方法,首先建立移动机器人路径规划的数学模型,介绍了蚁群算法、模拟退火算法的原理,然后考虑到蚁群算法搜索时间较长,易出现停滞现象的缺点,提出蚁群模拟退火算法来解决大范围海洋复杂环境下水下机器人的路径规划问题;通过仿真实验,表明所提算法有效,并且计算简单、收敛速度快,能够满足水下机器人导航的要求.     

改进粒子群在水下机器人路径规划中的应用

在海洋环境中水下机器人路径规划具有规划范围广阔、障碍物相对稀疏、海流的影响不可避免的特点。应用粒子群优化(PSO)算法实现水下机器人在复杂海洋环境中的路径规划,并从参数控制策略及拓扑模型方面进行改进,得到收敛精度更好的改进粒子群优化算法。设计了综合路径长度、海流和转向费用的适应度函数,使算法很好地适应海流的变化,很大程度减小了海流对水下机器人能量消耗和控制的不利影响。经仿真实验验证了算法的有效性,并能够很好地满足在复杂海况环境水下机器人路径规划的要求。     

基于生物启发模型的AUV三维自主路径规划与安全避障算法

针对自治水下机器人(AUV)的路径规划问题,在三维栅格地图的基础上,给出一种基于生物启发模型的三维路径规划和安全避障算法. 首先建立三维生物启发神经网络模型,利用此模型表示AUV的三维工作环境,神经网络中的每一个神经元与栅格地图中的位置单元一一对应;然后,根据神经网络中神经元的活性输出值分布情况自主规划AUV的运动路径.静态环境与动态环境下仿真实验结果表明了生物启发模型在AUV三维水下环境中路径规划和安全避障上的有效性.     

遗传算法在水下机器人路径规划中的应用

提出一种分层路径规划算法来解决大范围海洋环境下的智能水下机器人(AUV)的全局路径规划问题。该算法将机器人的工作空间分层分解,并在每一层搜索路径,最终得到一条与障碍物无碰的全局路径。同时为解决算法的全局最优问题,使用遗传算法在每一层搜索路径。实践证明,该方法具有灵活、实用的特点,并能显著的节省内存空间。     

人工蜂群算法在移动机器人路径规划中的应用

研究机器人路径规划优化问题,机器人工作环境复杂,运动路径上存在许多障碍物.针对提高机器人安全导航性能问题,传统群智能算法存在早熟、搜索效率低等难题,难以获得全局最优路径.为了获得最优机器人运动路径,避免碰撞的发生,提出了一种人工蜂群算法的机器人路径规划方法.首先采用栅格法对机器人工作环境进行建模,然后机器人路径规划目标点作为蜜源,最后蜂群之间信息交换、协作搜索最优机器人运动路径.结果表明,人工蜂群算法解决了传统群智能算法存在的难题,加快了机器人路径规划求解速度,以较短时间找到最短机器人运动路径.     

基于主从结构的多水下机器人协同路径规划

关于多水下机器人协同路径规划问题,是多水下机器人协同控制的重要研究内容之一,是一种典型的含多个约束条件的组合优化问题.针对多机器人协同路径规划因约束条件多导致算法复杂度高、耗时、求解困难等问题,提出了一种主从结构的并行多水下机器人协同路径规划算法.进化过程的每一代,子层结构应用粒子群并行算法,生成各架机器人当前的最优路径,同时,主层结构应用微分进化算法实时给出当前考虑机器人与障碍物、机器人与机器人之间避碰情况下,总系统运行时间最短的路径组合方案.上述结构将多约束分解到不同层面,有效地降低了单层结构因过多的约束条件计算时间过长以及不易实现等困难.仿真结果表明,上述算法不仅能在静态环境下生成可行的、优化的组合路径,而且在当障碍物随时间随机移动的动态环境下,也表现出可行的、良好的效果,为求解多水下机器人协同路径规划问题提供了一个高效的解决方案.     

移动机器人的路径规划算法与仿真

研究移动机器人全局路径优化的问题,由于机器人路径随机性强,空间大,存在冗余路径,影响规划速度.传统的进化算法存在着早熟的缺点而得不到最优路径.为了克服传统算法的缺点,提高进化算法的进化速度和精确性,将云理论和粗糙集相结合应用于机器人路径规划,以提高机器人路径规划的效率.仿真由栅格法描述环境随机生成初始路径群,首先利用粗糙集训练得出一系列可行路径的集合,然后利用云进化方法对种群优化,最终得最优行走路线.仿真结果验证改进算法在收敛速度和搜索质量上都有明显的改善.     

海流环境下多AUV多目标生物启发任务分配与路径规划算法

针对多障碍物海流环境下多自治水下机器人(AUV)目标任务分配与路径规划问题, 本文在栅格地图构建的 基础上给出了一种基于生物启发神经网络(BINN)模型的新型自主任务分配与路径规划算法, 并考虑海流对路径规 划的影响. 首先建立BINN模型, 利用此模型表示AUV的工作环境, 神经网络中的每一个神经元与栅格地图中的位 置单元一一对应; 接着, 比较每个目标物在BINN地图中所有AUV的活性值, 并选取活性值最大的AUV作为它的获 胜AUV, 实现多AUV任务分配; 最后, 考虑常值海流影响, 根据矢量合成算法确定AUV实际的航行方向, 实现AUV路 径规划与安全避障. 海流环境下仿真实验结果表明了生物启发模型在多AUV水下任务分配与路径规划中的有效性.     

Multi-AUV SOM task allocation algorithm considering initial orientation and ocean current environment

There is an ocean current in the actual underwater working environment. An improved self-organizing neural network task allocation model of multiple autonomous underwater vehicles (AUVs) is proposed for a three-dimensional underwater workspace in the ocean current. Each AUV in the model will be competed, and the shortest path under an ocean current and different azimuths will be selected for task assignment and path planning while guaranteeing the least total consumption. First, the initial position and orientation of each AUV are determined. The velocity and azimuths of the constant ocean current are determined. Then the AUV task assignment problem in the constant ocean current environment is considered. The AUV that has the shortest path is selected for task assignment and path planning. Finally, to prove the effectiveness of the proposed method, simulation results are given.

     

自治水下机器人的自主启发式生物启发神经网络路径规划算法

针对复杂海流环境下自治水下机器人(autonomous underwater vehicle, AUV)的路径规划问题,本文在栅格地图的基础上给出了一种基于离散的生物启发神经网络(Glasius bio-inspired neural networks, GBNN)模型的新型自主启发式路径规划和安全避障算法,并考虑海流对路径规划的影响.首先建立GBNN模型,利用此模型表示AUV的工作环境,神经网络中的每一个神经元与栅格地图中的位置单元一一对应;其次,根据神经网络中神经元的活性输出值分布情况并结合方向信度算法实现自主规划AUV的运动路径;最后根据矢量合成算法确定AUV实际的航行方向.障碍物环境和海流环境下仿真实验结果表明了生物启发模型在AUV水下环境中路径规划的有效性.     

A comparison of optimization techniques for AUV path planning in environments with ocean currents

To date, a large number of optimization algorithms have been presented for Autonomous Underwater Vehicle (AUV) path planning. However, little effort has been devoted to compare these techniques. In this paper, an quantum-behaved particle swarm optimization (QPSO) algorithm is introduced for solving the optimal path planning problem of an AUV operating in environments with ocean currents. An extensive study of the most important optimization techniques applied to optimize the trajectory for an AUV in several test scenarios is presented. Extensive Monte Carlo trials were also run to analyse the performance of these optimization techniques based on solution quality and stability. The weaknesses and strengths of each technique have been stated and the most appropriate algorithm for AUV path planning has been determined.     

Dynamic Task Assignment and Path Planning for Multi-AUV System in Variable Ocean Current Environment

An integrated multiple autonomous underwater vehicle (multi-AUV) dynamic task assignment and path planning algorithm is proposed by combing the improved self-organizing map (SOM) neural network and a novel velocity synthesis approach. Each target is to be visited by one and only one AUV, and a shortest path between a starting point and the destination is found in the presence of the variable current environment and dynamic targets. Firstly, the SOM neuron network is developed to assign a team of AUVs to achieve multiple target locations in dynamic ocean environment. The working process involves special definition of the rule to select the winner, the computation of the neighborhood function, and the method to update weights. Then, the velocity synthesis approach is applied to plan a shortest path for each AUV to visit the corresponding target in dynamic environment subject to the ocean current being variable and targets being movable. Lastly, to demonstrate the effectiveness of the proposed approach, simulation results are given in this paper.     

基于海图和改进粒子群优化算法的AUV全局路径规划

针对AUV（自主水下机器人）在复杂条件海域做全局路径规划时面临的环境信息缺少,环境建模困难和常规算法复杂、求解能力弱等问题,提出一种基于海图和改进粒子群优化算法的全局路径规划方法．首先利用电子海图的先验知识建立3维静态环境模型,并构造路径航程、危险度和平滑函数;在粒子群优化算法中引入搜索因子和同性因子自适应地调整参数,并结合鱼群算法的“跳跃”过程提升算法的求解能力．同时建立安全违背度和选优规则以提高所规划路径的安全性．仿真实验结果表明,本文方法与传统粒子群算法和蚁群算法相比,规划出短航程、安全性高的全局路径的能力更强,可满足AUV在复杂海域航行时的全局路径规划需求．     

Inverse optimal self-tuning PID control design for an autonomous underwater vehicle

This paper presents a new approach to path following control design for an autonomous underwater vehicle (AUV). A NARMAX model of the AUV is derived first and then its parameters are adapted online using the recursive extended least square algorithm. An adaptive Propotional-Integral-Derivative (PID) controller is developed using the derived parameters to accomplish the path following task of an AUV. The gain parameters of the PID controller are tuned using an inverse optimal control technique, which alleviates the problem of solving Hamilton–Jacobian equation and also satisfies an error cost function. Simulation studies were pursued to verify the efficacy of the proposed control algorithm. From the obtained results, it is envisaged that the proposed NARMAX model-based self-tuning adaptive PID control provides good path following performance even in the presence of uncertainty arising due to ocean current or hydrodynamic parameter.     

Imperialist Competitive Algorithm for AUV Path Planning in a Variable Ocean

An imperialist competitive algorithm (ICA) is introduced for solving the optimal path planning problem for autonomous underwater vehicles (AUVs) operating in turbulent, cluttered, and uncertain environments. ICA is a new sociopolitically inspired global search metaheuristic based on a form of competition between “imperialist” forces and opposing colonies. In this study, ICA is applied to optimize the coordinates of a set of control points for generating a curved spline path. The ICA-based path planner is tested to find an optimal trajectory for an AUV navigating through a variable ocean environment in the presence of an irregularly shaped underwater terrain. The genetic algorithm (GA) and quantum-behaved particle swarm optimization (QPSO) are described and evaluated with the ICA for the path optimization problem. Simulation results show that the proposed ICA approach is able to obtain a more optimized trajectory than the GA- or QPSO-based methods. Monte Carlo simulations demonstrate the robustness and superiority of the proposed ICA scheme compared with the GA and QPSO schemes.