变时延巡检小车遥操作仿人智能预估控制

针对目前解决遥操作系统网络变时延问题的控制方案存在稳定性与操作性间的矛盾、过于依赖被控对象模型精度和抗干扰性差等不足,提出了一种HSIC-Smith控制算法.首先,根据巡检小车典型的动态响应误差曲线,确定能恰当描述系统动态特性的特征模型;其次,在Smith预估原理的基础上,应用仿人智能控制算法对巡检小车不同的运动状态,采用开、闭环相结合的控制模式来减小Smith预估误差带来的影响,从而改善网络时延变化对巡检小车遥操作系统动态性能;最后,将该方案与常规的PID-Smith预估算法进行对比实验.实验结果表明:在存在网络变时延的条件下,谊方案能对巡检小车系统迅速、准确地遥操作控制,且对网络时延变化具有较强的适应性.     

大时延力反馈双边控制系统

阐述了力反馈双边控制遥操作的基本思想,讨论了其稳定性和透明性,介绍了一种既能保证稳定性、又能提高透明性的力反馈双边控制方法．最后给出了力反馈遥操作实验系统的实现,在6s时延条件下成功完成了曲面跟踪任务．     

空间遥操作机器人力反馈实验系统的研究与实现

本文讨论了在空间遥操作机器人系统中实现力反馈的基本结构及控制方案,并 基于虚功原理给出了实现手控器腕关节力反馈的具体算法．     

基于距离传感器的双边遥操作

为了改善双边遥操作的力反馈性能,本文根据从端操作臂上的传感器检测的目标距离信息,设计了新 的PD 双边控制器．证明了系统的稳定性条件,并通过单自由度双边遥操作实验系统,对提出的控制方法进行了实 验验证．实验结果表明,当从端操作臂靠近目标时,主端操作臂产生了逐渐增大的反馈力．这种控制策略为操作者 安全实现遥操作任务提供了有效手段．     

多信息感知辅助的网络遥操作机器人系统

构建了多信息感知辅助的网络遥操作机器人系统,该系统提供了一种通过多信息感知手段辅助操作者决策的远程控制方式．首先,分析了网络条件下遥操作机器人系统多信息感知的原理．该多信息包括机器人多传感器和网络返程时延等信息．通过对这些多信息的预处理、分类和决策处理,将该多信息以视觉、听觉、力觉、报警灯和交互文本方式转化为人可感知的信息．使用网络时延缓冲器和网络双连接,降低了网络可变时延对系统的影响．最后,长距离的网络遥操作实验验证了系统和控制策略的实用性和有效性．     

无环境力反馈的四通道双边控制

传统的四通道双边控制方法需要大量的力传感器,用以检测遥操作系统受到的环境力,在实际工程中不易推广应用.本文提出了一种无环境力反馈的四通道双边控制策略,分析了无时延和有时延两种情况下遥操作系统的透明性.并采用无源的双边控制律,设计了大时延情形下的系统控制结构.仿真结果表明,存在大时延时,提出的控制系统在自由运动和接触运动...     

遥操作机器人系统的变时延控制

由于遥操作机器人传输通道中存在着变化的通讯时延,造成了系统不稳定和操作性能降低等问题。为了消除或减少时延的影响,在利用RBF神经网络进行延时预测的基础上,通过改进型Smith预估器进行遥操作机器人的时延控制,从而使系统稳定,并易于操作。理论分析表明,该方案对时延的变化有较强的适应性,控制系统的鲁棒稳定性和动态品质均优于单纯的Smith预估补偿控制,且易于实现。仿真结果表明,在时延情况下,该方法可实现对遥操作机器人较为准确的测控。     

空间遥操作机器人主从双边自适应内模控制

天地大时延严重破坏具有力反馈的空间遥操作机器人系统的稳定性和透明性;针对天地大时延和未知的从手操作环境,基于内模控制和自适应控制思想设计一种自适应内模控制器;推导从手环境参数辨识模型,基于带遗忘因子的递推最小二乘滤波辨识环境模型,并利用辨识信息构建自适应内模控制器;基于单参数SNPIDC算法分别设计主手和从手自适应控制器;大量的仿真结果证明,在设计的主从双边自适应内模控制器作用下,空间遥操作机器人系统稳定性好,对未知环境适应能力强,系统透明性好,阻抗匹配程度高,且操作人员临场感强。     

面向多机器人遥操作的分布式预测图形仿真系统

在遥操作机器人系统中,由于存在通信传输时延,可能导致控制系统不稳定,从而降 低遥操作的效率和安全性．目前多采用预测仿真的方法来克服．在多机器人遥操作系统不但 要克服时延的影响,还要能控制机器人协调地完成遥操作任务．我们开发了一个面向多操作 者 多机器人遥操作的分布式预测图形仿真系统,实现了对多机器人遥操作系统的预测仿真 ,多个操作者可以通过人机交互接口遥控各自的机器人,相互协调完成遥操作的任务．初步 的实验表明该系统能够克服时延的影响,并能实现多操作者 多机器人的协调遥操作．这对 空间站机器人科学实验、多航行器对接等方面的研究有理论参考价值．     

虚拟手术中表面网格模型的力反馈算法与仿真

提出一个带力反馈的虚拟腹部外科手术系统,并重点研究及实现了基于表面网格模型的力反馈算法。为了提高系统的稳定性,使用基于线段与表面三角网格的碰撞检测方法;基于四阶Runge-Kutta方法的表面网格mass-spring模型进行变形仿真;基于力的广度优先传播来解决变形仿真的局部性。通过仿真实验验证了该原型系统可以实现与可变形的三维模型的实时力觉交互。最后,把该方法应用到虚拟腹部外科手术系统中,并实现带力反馈的手术仿真操作。     

Bilateral teleoperation through the Internet

This paper proposes a stable control structure for the bilateral teleoperation of robots through Internet. The problem is motivated by the increasing use of the Internet as a communication channel. Internet has a time-varying delay which depends on factors such as congestion, bandwidth and distance. In this work, we propose a control structure for the teleoperation of a manipulator robot with force feedback. Such a control structure includes state controllers (placed on the local and remote sites) and a time-delay compensation, which modifies the delayed position command generated by the human operator using the force that he feels in such a delayed moment and the current force between the slave and the remote environment. In addition, the proposed control scheme is designed considering a model of the communication channel. Finally, experiments of bilateral teleoperation of robots through Intranet and Internet are shown to test the performance and stability of the designed teleoperation system.     

Teleoperation of Mobile Robots With Time-Varying Delay

This paper proposes a stable control scheme for teleoperation of mobile robots with visual feedback in presence of time-varying delay. The proposed control scheme is based on using a model of the human operator to combine (on the remote site) the velocity command generated by the human operator in a delayed time instant, the received information (which stimulates the operator) in such moment, and the current state of the remote site to set the velocity reference, which is applied to the mobile robot. In addition, the proposed control scheme does not modify the information sent from the remote site to the local site. On the other hand, the proposed scheme uses estimated parameters of the human operator and a fictitious force, which is calculated using data fusion from ultrasonic sensors and optical flow field taken from panoramic images. To illustrate the performance and stability of the proposed control structure, several teleoperation experiments between Argentina and Brazil linked via Internet are shown.     

无时延感的遥操作实时共享控制仿真

针对遥操作存在大延时和临场感缺失等问题,提出了一种融合多种技术的无时延感的空间遥控机器人实时共享控制系统;重点研究了融合双向力反馈、传感器局部自主控制、图形预显示和遥编程的无时延感遥操作技术;计算仿真实验验证了该系统及其技术的有效性。     

Adaptive passive control with varying time delay

This paper presents a passive control scheme for a force reflecting bilateral teleoperation system with a varying time communication delay. To improve the stability and performance of the system, the master and slave must be coupled dynamically via a transmission network through which the force and velocity are communicated bilaterally. However, the time delay caused by various factors, such as the transmission distance, network congestion, and communication bandwidth, is a long-standing impediment to bilateral control that can destabilize the system. In this study, we investigated how a varying time delay affects the stability of a teleoperation system. A new optimal adaptive approach based on a passive control scheme was designed bilaterally for both the master and slave sites. Extra variables were transmitted together with the wave variables in the scattering system. The proposed scheme achieved both passive control, and an acceptable tracking performance. The tracking performance was demonstrated using a computer simulation of varying time delays in a bilateral teleoperation system.     

Teleoperation Control of a Position‐Based Impedance Force Controlled Mobile Robot by Neural Network Learning: Experimental Studies

Effective haptic performance in teleoperation control systems can be achieved by solving two major problems: the time‐delay in communication channels and the transparency of force control. The time‐delay in communication channels causes poor performance and even instability in a system. The transparency of force feedback is important for an operator to improve the performance of a given task. This article suggests a possible solution for these two problems through the implementation of a teleoperation control system between the master haptic device and the slave mobile robot. Regulation of the contact force in the slave mobile robot is achieved by introducing a position‐based impedance force control scheme in the slave robot. The time‐delay problem is addressed by forming a Smith predictor configuration in the teleoperation control environment. The configuration of the Smith predictor structure takes the time‐delay term out of the characteristic equation in order to make the system stable when the system model is given a priori. Since the Smith predictor is formulated from exact linear modeling, a neural network is employed to identify and model the slave robot system as a nonlinear model estimator. Simulation studies of several control schemes are performed. Experimental studies are conducted to verify the performance of the proposed control scheme by regulating the contact force of a mobile robot through the master haptic device.     

无源散射变换的双边移动机器人网络遥操作

网络遥操作系统的随机时延给控制器设计带来巨大挑战,严重时破坏系统的稳定性。首先对遥操作无源理论及其波变量控制方法做了简单综述,然后提出直接无源散射变换方法,它将无源双边控制方法推广到具有随机时延的网络遥操作系统中去,保证网络遥操作系统在任何不对称随机网络时延情况下稳定。最后基于此变换方法设计了一个虚拟主从手双边移动机器人网络遥操作方案,并进行了仿真验证,结果表明结出的设计方法能满足系统性能要求。     

基于Web的并联雕刻机远程汉字雕刻技术

为实现资源共享和遥控作业，设计并实现了基于Web的并联雕刻机远程汉字雕刻系统，系统包括远动控制、雕刻控制和视频反馈3部分功能。采用监督控制方式以便减少网络延时对雕刻控制的影响，进程互斥原理解决了多用户同时雕刻的冲突，多线程和共享变量机制可保证雕刻作业的实时控制。为了适用不同类型的图像采集卡，基于JMF和IP组播两种方案分别实现了视频信息的连续传输。实验结果验证了该方法的可行性和有效性。     

遥操作机器人客户端仿真系统的设计与实现

该文面向空间机器人遥操作,应用三维预测仿真和遥传感器反馈监控技术,建构了遥操作机器人的客户端仿真系统.实现了简单的柔顺力控制操作的仿真.操作员通过仿真系统面向的虚拟环境离线编程,实现对遥操作任务的预演.同时基于遥传感器反馈信息的识别,实现了对远端任务执行进程的监控和状态流图显示.在模拟的大时延情况下,操作员能够在客户端通过局域网控制实验室中的机器人完成精密插孔装配等任务.为进行大时延遥操作提供了算法实验平台.     

Variable admittance force feedback device and its human-robot interaction stability

In teleoperation, a force feedback device is a medium to build a transparent interaction environment between a human and a remote robotic arm. Using force feedback devices, the users can operate the remote robotic arm intuitively and perceive remote interaction through the force channel, just as if they are in the remote environment. Compared with impedance devices, admittance devices have the advantages of large feedback output, high stiffness, high reverse driving performance, and flexible structure, which are more suitable for the teleoperation of heavy-duty and large-size robotic arms. However, the control of admittance devices is relatively complex and has some inherent limitations such as response delay, instability from high-frequency oscillation, difficulty in achieving constant speed control, etc. Errors in admittance model parameters and human physiological characteristics, such as force application fluctuations, are the root causes of these problems. In this study, we proposed a fuzzy variable damping admittance algorithm, which allows the device to identify the user's movement intention and give respond quickly and accurately. We also established a human-robot interaction (HRI) system model of an admittance master controller device and summarized the principles of the admittance parameter configuration of a stable system. For the device's high-frequency oscillation instability caused by human arm stiffness, we propose an oscillation observation and reduction algorithm. By observing the force signal change characteristics, the algorithm can quickly detect the unstable behavior caused by human hands and perform oscillation reduction. To reduce the influence on upper limb uniform motion caused by fluctuating force application, we proposed a constant velocity intention inference algorithm based on a velocity spherical cone to smooth out the device operating velocity to achieve smooth control. The method proposed in this study achieved stable control in a 6 DOF force feedback device as a master controller, and the effect has been verified by experiments.     

Human-centered control scheme for delayed bilateral teleoperation of mobile robots

Teleoperation task performance strongly depends on how well the human operator’s commands are executed. In this paper, we propose a control scheme for delayed bilateral teleoperation of mobile robots that considers user’s commands execution in order to achieve a high-performance teleoperation system in some important aspects like time to complete the task, safety, and operator dependence. We describe some evaluation metrics that allow us to address these aspects and a quantitative metric is proposed and incorporated in the control scheme to compensate wrong commands. A force feedback is applied to the master at the local site as a haptic cue. In addition, the system stability is analyzed taking into consideration the master and remote robot dynamic models and the asymmetric time-varying delays of the communication channel. Multiple human-in-the-loop simulations were carried out and the results of the evaluation metrics were discussed. Additionally, we present experiments where a user teleoperates a mobile robot via the Internet connection between Argentina and Italy.