基于交哺行为的多机器人任务一致性保持

针对多机器人领域Mission级任务研究滞后于Task级任务研究的问题,提出了一种MTB三层多机器人任务体系结构。模拟蜜蜂和蚂蚁等社会性生物的交哺行为,提出了一种多机器人系统Mission级任务一致性保持方法。建立了该方法的数学模型。仿真结果表明该方法具有很好的鲁棒性、可靠性和系统可扩展性。     

基于焦虑概念和拍卖方法的多机器人协作搜集

针对目前应用于多机器人搜集任务的拍卖方法很少考虑机器人参与拍卖的时机是否适当这一问题,在拍卖方法中引入了心理学的焦虑概念,提出了基于焦虑/拍卖的多机器人协作搜集方法.通过对机器人焦虑程度的量化反映其对环境、队友及自身状况的评价,进而反映其对自己独立完成任务的不自信程度和对队友提出的拍卖邀请的主观接受程度.实验结果表明,与单纯的拍卖方法相比,该方法能提高多机器人协作搜集任务的执行效率.     

基于人工免疫系统的异构多机器人联盟形成

对动态环境下多机器人联盟形成问题进行了研究,提出了一种基于人工免疫系统的异构多机器人联盟形成方法.该方法在对比人工免疫系统与多机器人系统相似关系的基础上,利用人工免疫系统的隐喻机制为面向动态感知任务的异构多机器人联盟形成问题提供了一种新的思路和解决方法.进行了未知非结构化环境下的多机器人协作搜集仿真实验,仿真结果表明所提方法可以使多机器人系统自主地形成机器人联盟以完成动态感知任务,提高了多机器人系统执行任务的效率.     

基于一种蚁群算法的多机器人动态感知任务分配

多机器人系统在具有任务聚集特征的动态感知任务环境下执行搜集任务时,存在着由于任务分配不当而引起的冲突加剧问题.针对这一问题,提出了一种基于排斥信息素型蚁群算法的多机器人任务自主分配方法.进行了未知非结构化环境下的多机器人协作搜集仿真实验.仿真结果表明,采用本文所提方法可以实现多机器人搜集任务的自主分配,有效减少机器人的空间冲突,尤其在机器人数量较多的情况下,更能显示出该方法的优势.     

基于协作协进化的多智能体机器人协作研究

协作问题一直是自主多智能体机器人系统研究的关键问题之一。基于多智能体机器人系统的CCP协作协议所生成的各智能体机器人的任务序列依赖于目标的初始顺序,因此难以得到最优解。文章提出了利用协作协进化来实现多智能体机器人之间协作的一种机制。该方法采用基于协作种群的技术来生成多智能体机器人任务执行序列,在给定的任务分解产生的所有可能解中寻找最优解,并通过交换局部知识和并行决策等手段来优化系统的性能。利用该机制,对3个智能体协作搬运8个物体进行计算机模拟,结果表明,该机制在优化任务执行序列方面作用明显,从而能有效提高多智能体机器人系统的性能。     

基于评价选择策略的Internet多机器人协作控制研究

针对Internet多机器人系统中存在的操作指令延迟、工作效率低、协作能力差等问题,提出了多机器人神经元群网络控制模型。在学习过程中,来自不同功能区域的多类型神经元连接形成动态神经元群集,来描述各机器人的运动行为与外部条件、内部状态之间复杂的映射关系,通过对内部权值连接的评价选择,以实现最佳的多机器人运动行为协调。以互联网足球机器人系统为实验平台,给出了学习算法描述。仿真结果表明,己方机器人成功实现了配合射门的任务要求,所提模型和方法提高了多机器人的协作能力,并满足系统稳定性和实时性要求。     

编队控制中的机器人行为与基于服务的运动行为结构设计

以基于位姿误差的虚拟目标跟踪为控制模式,提出了独立于编队控制与协作任务,但却适用于多移动机器人编队运动的基于服务的机器人运动行为结构,并对其基本运动行为与选择方法进行了设计.提出的基于服务的机器人行为结构借鉴了软件工程领域的面向服务的架构思想,具有可重用性.多机器人编队形成、改变等仿真与实验验证了本文所提方法的有效性.     

基于案例的异构多机器人系统的协作研究

目的是研究异构多机器人系统中机器人之间的协作过程.基于足球比赛案例,将异构多机器人系统的任务分为找球、跟随、踢球等几个作业.以人形机器人和轮式机器人作为研究对象,并赋予不同的功能,对机器人能力进行建模.讨论如何以优化的方案分配给执行任务的机器人,并建立了一种参考模型.最后,以流程图方式说明了机器人的行为控制.实践表明,由具有不同能力的机器人共同协作可以更加有效地完成任务.     

基于强化学习的未知环境多机器人协作搜集

针对多机器人协作复杂搜集任务中学习空间大,学习速度慢的问题,提出了带共享区的双层强化学习算法。该强化学习算法不仅能够实现低层状态-动作对的学习,而且能够实现高层条件-行为对的学习。高层条件-行为对的学习避免了学习空间的组合爆炸,共享区的应用强化了机器人间协作学习的能力。仿真实验结果说明所提方法加快了学习速度,满足了未知环境下多机器人复杂搜集任务的要求。     

基于结构自适应的多机器人协作机制研究

未知环境下的多机器人合作是一个复杂的控制问题.它的解决方案要求在机器人内部任务目标与机器人之间的任务目标间保证有适当的均衡,而机器人间的协作是多机器人系统高效工作的关键.证明了一种分布式的结构自适应的组织模型在MAS中是鲁棒的和高效的.基于自组织的原则,在执行任务时机器人可以通过任务分配实时改变组织结构.各机器人之间通过任务分配的关系记录来确定下一步的关系.实验证明:此方法能接近到集中式控制方法的上界,优于静态的和随机的任务分配方法.     

基于遗传算法的多机器人系统最优轨迹规划

针对关节型多机器人系统在静态环境下的点到点的轨迹规划问题,提出了一种基于遗传算法的最优轨迹规划策略.采用遗传算法在综合考虑各机器人沿轨迹运动的安全性、运动代价以及运动学约束的基础上为单个机器人规划最优的运动轨迹,并通过协调各机器人沿预定轨迹运行的时间避免机器人之间碰撞的发生.针对含有3个二自由度平面关节型机器人的多机器人系统进行了仿真实验,实验结果验证了该方法的有效性.     

栅格地图中多机器人协作搜索目标

目标搜索是多机器人领域的一个挑战.本文针对栅格地图中多机器人目标搜索算法进行研究.首先,利用Dempster-Shafer证据理论将声纳传感器获取的环境信息进行融合,构建搜索环境的栅格地图.然后,基于栅格地图建立生物启发神经网络用于表示动态的环境.在生物启发神经网络中,目标通过神经元的活性值全局的吸引机器人.同时,障碍物通过神经元活性值局部的排斥机器人,避免与其相撞.最后,机器人根据梯度递减原则自动的规划出搜索路径.仿真和实验结果显示本文提及的算法能够实现栅格地图中静态目标和动态目标的搜索.与其他搜索算法比较,本文所提及的目标搜索算法有更高的效率和适用性.     

Robust multi-robot coordination in pick-and-place tasks based on part-dispatching rules

This paper addresses the problem of realizing multi-robot coordination that is robust against pattern variation in a pick-and-place task. To improve productivity and reduce the number of parts remaining on the conveyor, a robust and appropriate part flow and multi-robot coordinate strategy are needed. We therefore propose combining part-dispatching rules to coordinate robots, by integrating a greedy randomized adaptive search procedure (GRASP) and a Monte Carlo strategy (MCS). GRASP is used to search for the appropriate combination of part-dispatching rules, and MCS is used to estimate the minimum-maximal part flow for one combination of part-dispatching rules. The part-dispatching rule of first-in–first-out is used to control the final robot in the multi-robot system to pick up parts left by other robots, and the part-dispatching rule of shortest processing time is used to make the other robots pick up as many parts as possible. By comparing it with non-cooperative game theory, we verify that the appropriate combination of part-dispatching rules is effective in improving the productivity of a multi-robot system. By comparing it with a genetic algorithm, we also verify that MCS is effective in estimating minimum-maximal part flow. The task-completion success rate derived via the proposed method reached 99.4% for 10,000 patterns.     

Task Modelling in Collective Robotics

Does coherent collective behaviour require an explicit mechanism of cooperation? In this paper, we demonstrate that a certain class of cooperative tasks, namely coordinated box manipulation, are possible without explicit communication or cooperation mechanisms. The approach relies on subtask decomposition and sensor preprocessing. A framework is proposed for modelling multi-robot tasks which are described as a series of steps with each step possibly consisting of substeps. Finite state automata theory is used to model steps with state transitions specified as binary sensing predicates called perceptual cues. A perceptual cue (Q), whose computation is disjoint from the operation of the automata, is processed by a 3-level finite state machine called a Q-machine. The model is based on entomological evidence that suggests local stimulus cues are used to regulate a linear series of building acts in nest construction. The approach is designed for a redundant set of homogeneous mobile robots, and described is an extension of a previous system of 5 box-pushing robots to 11 identical transport robots. Results are presented for a system of physical robots capable of moving a heavy object collectively to an arbitrarily specified goal position. The contribution is a simple task-programming paradigm for mobile multi-robot systems. It is argued that Q-machines and their perceptual cues offer a new approach to environment-specific task modelling in collective robotics.     

基于博弈论的多机器人系统任务分配算法

对多机器人系统任务分配策略进行了形式化描述,为任务分配方案的求解提供了一种数学描述工具;针对多机器人系统中机器人决策之间的相互依存性,引入博弈论的思想分析了多机器人系统的任务分配问题,提出了一种基于博弈论的多机器人系统任务分配算法(GT-MRTA).实验结果表明,算法复杂度较低,计算量较小,鲁棒性较好,获得的任务分配方案质量较高.     

基于协助校正方法的多机器人主动同时定位与建图

协作策略是多机器人主动同时定位与建图(SLAM)的关键。文中提出一种多机器人相互校正的协作策略, 称为协助校正。 该方法通过优化机器人对陆标的观测来提高定位与建图的精度, 共包括弱协助校正和强协助校正两种模式。 前者是一种间接的协助模式, 可应用于所有机器人自身定位均不准确的情形。 后者是一种直接的协助模式, 由自身定位精度较高的机器人主动校正其它机器人及相应陆标。 文中将这两种协助校正模式利用状态机统一到多机器人主动SLAM应用中。在仿真实验中将协助校正与其它多机器人主动SLAM方法进行对比以验证其精度优势, 并与单机器人主动SLAM对比以验证其导航代价极低的优势。最后在两台Poineer3-DX移动机器人上进行真实环境实验,实验结果证实协助校正方法可在实际应用中有效提高多机器人主动SLAM的探索效率和精度。     

基于双移动信标的多机器人编队控制算法

针对多机器人在未知环境下的编队控制问题,提出了一种基于双移动信标的多机器人编队算法.该方法在以两个移动信标机器人为领航机器人的基础之上,设计了基于超宽带测距技术的多机器人定位模型,通过摔制从机器人的位姿状态,实现多机器人编队控制,并且设计了多传感器数据融合算法,有效提高多机器人编队的精度.该方法解决了多机器人在未知环境中的编队控制问题,提高了多机器人编队控制的精度.仿真结果表明了该方法的可行性和有效性.     

Particle Filter for Collaborative Multi-Robot Localization Tolerant to Recognition Error

Statistical algorithms using particle filters have been proposed previously for collaborative multi-robot localization. In these algorithms, by synchronizing each robot's belief or exchanging the particles of the robots, fast and accurate localization is attained. However, there algorithms assume correct recognition of other robots and the effects of recognition error are not considered. If the recognition of other robots is incorrect, a large amount of error in localization can occur. This paper describes this problem. Furthermore, in order to cope with the problem, an algorithm for collaborative multi-robot localization is proposed. In the proposed algorithm, the particles of a robot are exchanged with those of other robots according to measurement results obtained by the sending robot. At the same time, some particles remain in the sending robot. Received particles from other robots are evaluated using measurement results obtained by the receiving robot. The proposed method copes with recognition error by using the remaining particles, and increases the accuracy of estimation by twice evaluating the exchanged particles of the sending and receiving robots. These properties of the proposed method are argued mathematically. Simulation results show that incorrect recognition of other robots does not cause serious problems in the proposed method.     

An improved PSO-based approach with dynamic parameter tuning for cooperative multi-robot target searching in complex unknown environments

Target searching in complex unknown environments is a challenging aspect of multi-robot cooperation. In this paper, an improved particle swarm optimisation (PSO) based approach is proposed for a team of mobile robots to cooperatively search for targets in complex unknown environments. The improved cooperation rules for a multi-robot system are applied in the potential field function, which acts as the fitness function of the PSO. The main improvements are the district-difference degree and dynamic parameter tuning. In the simulation studies, various complex situations are investigated and compared to the previous research results. The results demonstrate that the proposed approach can enable the multi-robot system to accomplish the target searching tasks in complex unknown environments.     

A collaborative localization tolerant to recognition error by double-check particle exchange

Statistical algorithms using particle filters for collaborative multi-robot localization have been proposed. In these algorithms, by synchronizing every robot’s belief or exchanging particles of the robots with each other, fast and accurate localization is attained. These algorithms assume correct recognition of other robots, and the effects of recognition errors are not discussed. However, if the recognition of other robots is incorrect, a large amount of error in localization can occur. This article describes this problem. Furthermore, an algorithm for collaborative multi-robot localization is proposed in order to cope with this problem. In the proposed algorithm, the particles of a robot are sent to other robots according to measurement results obtained by the sending robot. At the same time, some particles remain in the sending robot. Particles received from other robots are evaluated using measurement results obtained by the receiving robot. The proposed method is tolerant to recognition error by the remaining particles and evaluating the exchanged particles in the sending and receiving robots twice, and if there is no recognition error, the proposed method increases the accuracy of the estimation by these two evaluations. These properties of the proposed method are argued mathematically. Simulation results show that incorrect recognition of other robots does not cause serious problems in the proposed method.