基于事件相关电位的水下机械手脑电波控制

为了解放水下机械手操作人员的双手,本文将脑-机接口(BCI)技术应用到水下机器人作业中,通过解析脑电信号并将其映射为具体指令从而控制机械手.现有的脑电波控制机械手方法在实时性、准确性方面无法满足实际的水下作业要求,提出了基于视觉诱发模式的ERP(事件相关电位)脑电信号来控制水下机械手的策略.通过融合脑电波控制与水下机械手作业的各自特点和优化ERP视觉诱发界面,使操作人员能够快速地完成给定任务.8位被试被邀请在建立的实验平台上进行控制实验,最终得到的辨识操作人员意图平均准确率、系统信息传输率与完成任务平均控制时间分别为91.5%、27.7 bits/min与90.1 s.与同类系统相比,本文所提控制策略系统性能更好,且作业效率满足实际作业要求.     

机器人作业的离散事件建模与控制方法

针对传统机器人控制中规划器开环的不足, 首先设计了底层的非时间参考的连续路径规划与控制方法, 使规划器的规划值基于系统的状态之上, 避免了基于时间规划的系统由于意外事件造成的损害和任务的重新规划; 在此基础上, 又建立了整个作业任务的离散事件模型, 设计了离散事件路径规划方法及控制综合方法, 实现了事件反馈的闭环, 提高了系统处理不确定事件的能力和作业的自动化程度. 最后两台PUMA560机械手搬运被识别工件的作业验证了本文算法的有效性.     

基于深度强化学习与多参数域随机化的水下机械手自适应抓取研究

以水下机械手自主作业的应用需求为背景,针对水下机械手动力学参数时变、工作环境复杂、传感器限制、控制精度低等问题,基于强化学习与多参数域随机化理论提出一个具有通用性的水下机械手作业框架。首先,建立基本的机器人强化学习控制系统,然后采用多参数域随机化方法增强强化学习训练策略的稳定性与策略迁移效果,包括机械手动力学参数、水动力参数、状态空间与动作空间的噪声和延时等;最后,将训练的策略分别迁移到一个新的机器人仿真环境与一款真实的工作级水下机械手上进行实验。大量实验验证了本文所提方法的有效性,为未来真实海域自主作业奠定了基础。     

潜器对接及其虚拟现实仿真技术的研究

海洋空间对接是援潜救生技术中最关键的内容．根据援潜救生机器人的作业特点，本 文对其进行了基于离散事件系统（DES）的作业规划［1］；给出了各阶段必要的信息 处理方法；并针对基于DES控制系统用常规方法仿真结果不直观的缺陷，设计了潜器对接虚 拟现实系统，最后展示了运用该系统对潜器对接过程仿真的结果．     

水下机器人多功能作业工具包

本文首先阐述了水下机器人作业工具包的重要性，重点研究了水下机械手的原理、 功能及两种主要结构．并以沈阳自动化所研制的缆控水下机器人为背景，讨论了水下作业工 具包的一些专用工具的原理及其结构．     

作业型飞行机器人研究现状与展望

作业型飞行机器人是指由飞行机器人(通常是旋翼飞行机器人)与作业装置(机械臂)共同组成的具有主动作业能力的一种新型机器人系统.由于主动作业装置与飞行机器人之间的紧密耦合,以及飞行机器人本身对外部干扰的敏感性,作业型飞行机器人系统的研究也面临着诸多难题,如:机械臂运动引起系统重心变化带来的建模与镇定问题,与外界持续接触作业时的安全协调控制问题,以及相应的运动学、动力学规划问题等等.本文将全面分析与总结近几年发表的资料与文献,对作业型飞行机器人系统及相应的动力学建模与耦合分析、自主控制等方面的主要研究成果进行综述,并对其中的关键问题与困难进行分析与展望.     

基于能源消耗最小的自治水下机器人-机械手系统协调运动研究

描述了自治水下机器人搭载的三功能水下电动机械手的设计．鉴于自治水下机器人—机械手系统是运动学冗余的且自带能源,因此将系统阻力优化函数引入逆运动学求解,设计了基于系统能源消耗最小的系统协调运动规划算法．仿真表明,该算法在解决系统冗余度的同时,有效地减小了系统能源消耗．     

AUV控制系统规划层使命与任务协调方法研究

以地形勘查使命为背景,对AUV(自治式水下机器人)规划层使命与任务协调方法进行了研究．介绍了AUV控制系统的逻辑结构,采用分层Petri网对AUV规划层离散事件系统进行了建模,通过对向目标区域航行任务库所进行扩展阐述了任务规划层的分层Petri网模型．提出了一种基于改进RW离散事件监控理论的协调方法,分别阐述了AUV使命与任务规划层离散事件系统的监控与协调．最后,通过湖试试验验证了AUV规划层使命与任务协调方法的正确性．     

基于能源消耗最小的自治水下机器人一机械手系统协调运动研究

描述了自治水下机器人搭载的三功能水下电动机械手的设计．鉴于自治水下机器人一机械手系统是运动学冗余的且自带能源，因此将系统阻力优化函数引入逆运动学求解，设计了基于系统能源消耗最小的系统协调运动规划算法．仿真表明，该算法在解决系统冗余度的同时，有效地减小了系统能源消耗．     

一个多机器人制造系统的设计与实现

本文构建了一个包含多个机器人和自动化物流单元的柔性制造系统，其中机器人部分包括一个自动导引小车和两台装配机器人，物流单元部分包括一个小型立体仓库和一条自动传输线．系统采用递阶分散式的体系结构，每个作业单元均有独立的控制器，并通过串行接口实现与主控计算机的实时通讯．在对系统作业任务进行有限状态机建模的基础上，采用基于事件的控制思想实现了多个作业单元的协调控制，提高了系统的柔性和鲁棒性，实验结果也证明了系统设计的有效性．     

Disturbance observer-based robust control for underwater robotic systems with passive joints

Underwater exploration requires mobility and manipulation. Underwater robotic vehicles (URV) have been employed for mobility, and robot manipulators attached to the underwater vehicle (i.e. rover) perform the manipulation. Usually, the manipulation mode takes place when the rover is stationary. The URV is then modeled as a passive joint and joints of the manipulator are modeled as active joints. URV motions are determined by inherent dynamic couplings between active and passive joints. Furthermore, the control problem becomes complex since there are many hydrodynamic terms as well as intrinsic model uncertainties to be considered. Tocope with these difficulties, we propose a disturbance observer-based robust control algorithm for underwater manipulators with passive joints. The proposed control algorithm is able to treat an underactuated system as a pseudo-active system in which passive joints are eliminated. Also, to realize a robust control method, a non-linear feedback disturbance observer is applied to each active joint. A four-jointed underwater robotic system with one passive joint is considered as an illustrative example. Through simulation, it is shown that the proposed control algorithm has good position tracking performance even in the presence of several external disturbances and model uncertainties.     

A coordinated control of an underwater vehicle and robotic manipulator

Remotely operated underwater robotic vehicles (URVs) have been used for various tasks: inspection, recovery, construction, etc. With the increased utilization of remotely operated vehicles in subsea applications, the development of autonomous vehicles becomes highly desirable to enhance operator efficiency. However, engineering problems associated with the high density, nonuniform and unstructured seawater environment, and the nonlinear response of the vehicle make a high degree of autonomy difficult to achieve. The vehicles are usually equipped with mechanical manipulators that are utilized during the working mode. The accurate performance of the vehicle during the working mode can be achieved by controlling the vehicle and manipulator at the same time and compensating the end-effector error due to the vehicle motion. This article describes an adaptive control strategy for the coordinated control of an underwater vehicle and its robotic manipulator. The effectiveness of the control system is investigated by case study. The results show that the presented control system can provide the high performance of the vehicle and manipulator in the presence of unpredictable changes in the dynamics of the vehicle and its environment.     

Experiments in the coordinated control of an underwater arm/vehicle system

The addition of manipulators to small autonomous underwater vehicles (AUVs) can pose significant control challenges due to hydrodynamic interactions between the arm and the vehicle. Experiments conducted at the Monterey Bay Aquarium Research Institute (MBARI) using the OTTER vehicle have shown that dynamical interactions between an arm and a vehicle can be very significant. For the experiments reported in this paper, a single-link arm was mounted on OTTER. Tests showed that for 90-degree, two-second repetitive slews of the arm, the vehicle would move as much as 18 degrees in roll and 14 degrees in yaw when no vehicle control was applied.Using a new, highly accurate model of the arm/vehicle hydrodynamic interaction forces, which was developed as part of this research, a coordinated arm/vehicle control strategy was implemented. Under this model-based approach, interaction forces acting on the vehicle due to arm motion were predicted and fed into the vehicle controller. Using this method, station-keeping capability was greatly enhanced. Errors at the manipulator end point were reduced by over a factor of six when compared to results when no control was applied to the vehicle and by a factor of 2.5 when compared to results from a standard independent arm and vehicle feedback control approach. Using the coordinated-control strategy, arm end-point settling times were reduced by a factor three when compared to those obtained with arm and vehicle feedback control alone. These dramatic performance improvements were obtained with only a five-percent increase in total applied thrust.     

A method for forming program control for velocity regime of motion of underwater vehicles along arbitrary spatial trajectories with given dynamic accuracy

An approach to precise control of motion of an underwater vehicle is proposed; this approach consists in an automatic correction of program motion signals such that the execution of these new program signals provides precise motion of the underwater vehicle along a given spatial trajectory with maximum possible velocity irrespective of dynamic error of the control system of this underwater vehicle. The program signals of motion of the underwater vehicle are corrected by shifting the target point specifying the desired position of the underwater vehicle on a given trajectory by a value proportional to the vector of deviation of the underwater vehicle from this trajectory and simultaneous adjustment of the desired velocity of the underwater vehicle. The results of mathematical simulation have shown that the application of the proposed method provides exact and maximally fast motion of the underwater vehicle along the given spatial trajectory using simple standard linear controllers in the control system of this underwater vehicle.     

基于递归神经网络的水下机器人故障辨识

水下机器人故障检测与辨识是机器人实现主动客错控制的关键.针对一般非线性系统执行器和传感器故障辨识问题构造了一种基于递归神经网络的故障辨识模型,并将其应用于水下机器人执行器与传感器故障检测和辨识中.2个并行递归神经网络根据水下机器人实际输出与估计输出间的误差学习调整隐藏层与输出层权矩阵,辨识机器人中发生的执行器故障和传感...     

基于多传感器信息融合的水下运动体速度测量

针对水下运动体测速中存在的难度大、精度低等问题,提出一种基于加速度计和机械测速装置的融合测速方法。该方法实质上是一种改良的模糊自适应卡尔曼滤波,在常规卡尔曼滤波的基础上,引入了自适应参数,并通过模糊控制器对残差的监控来实时调整自适应参数。经Matlab仿真和实际试验证实:该方法可以有效地提高卡尔曼滤波器的跟踪性,并改善滤波效果,适用于通用的水下运动体测速。     

Redundant manipulator techniques for partially decentralized path planning and control of a platoon of autonomous vehicles.

An approach to real-time trajectory generation for platoons of autonomous vehicles is developed from well-known control techniques for redundant robotic manipulators. The partially decentralized structure of this approach permits each vehicle to independently compute its trajectory in real-time using only locally generated information and low-bandwidth feedback generated by a system exogenous to the platoon. Our work is motivated by applications for which communications bandwidth is severely limited, such for platoons of autonomous underwater vehicles. The communication requirements for our trajectory generation approach are independent of the number of vehicles in the platoon, enabling platoons composed of a large number of vehicles to be coordinated despite limited communication bandwidth.     

Robust feedback stabilization of underwater robotic vehicles

The controlled motion of an underwater vehicle is very likely to be affected by arbitrary disturbances with considerable magnitudes. In this paper, we develop a simple approach for optimal robust control design of underwater robotic vehicles having decentralized input-output structure. Our design method is based on an explicit condition on the control input matrix which has been found to be necessary and sufficient for a decentralized control system to be robust against arbitrary, but otherwise, bounded disturbances. That makes it possible to get optimal trade-off relations between the bounds of disturbances, the system output accuracy, and the control force limits. For the robust control design purpose, we apply decentralized sliding-mode control the stability of which can be easily verified using Lyapunov theory. In order to show the effectiveness of the design method, the controlled planar motion of an underwater robotic vehicle is taken as an illustrative example.     

基于有限时间系统同步的自治水下航行器回收控制

基于主-从系统状态同步的思想,提出了母艇在平面运动中回收自治水下航行器（Autonomous underwater vehicle,AUV）的一种控制方法. 在给出母艇和自治水下航行器的动力学模型基础上,建立了自治水下航行器（从系统）接收母艇（主系统）的状态信息并控制自身接近母艇的主从控制方案,使母艇自主回收水下航行器的问题转化为两者的运动状态同步问题. 利用有限时间稳定性理论,设计了一种在常值海流扰动影响下,自治水下航行器能够在有限时间内被母艇回收的滑模控制器,理论证明和仿真实例证实了该控制器的有效性.