一个新的力觉临场感系统模型

本文提出了一个新的力觉临场感系统模型，讨论了它的二端口网络结构，推导了相应的网络特性参数，分析了参数的含仪和测量方法。此外，对理想系统的参数也进行了分析，本文的研究为临场感技术的发展提供了基础。     

基于移动通信网络的机器人遥操作

提出了一种基于移动通信网的多机器人遥操作方案,解决了在恶劣的移动环境中如何保证系统稳定性,并进行具有实时力觉、视觉反馈的双向遥操作等问题。其中通过比较现存的各种视频压缩标准,结合关键帧提取、帧分割等技术,提出了一种移动网中的实时视频传输方案。一系列室外机器人群编队行进实验验证了方案的有效性。     

基于虚拟现实的空间机器人遥操作地面实验研究

以空间机器人在轨服务为背景,建立了基于虚拟现实的机器人臂/灵巧手遥操作地面实验系统,模拟了空间机器人遥操作的情形.系统主要包括虚拟环境建模、人-机交互接口设计、机器人运动学建模和时延模拟环节.利用该遥操作系统,在模拟的地面-空间大时延（约10 s）遥操作条件下,完成了销孔装配的典型空间装配任务.验证了在结构化环境中遥操作时,虚拟现实技术克服大时延影响的有效性.     

Digital versus analog control of bilateral teleoperation systems: A task performance comparison

Controller discretization has the potential to jeopardize the stability of a bilateral teleoperation system. As reported in the literature, stability conditions impose bounds on the gains of the discrete-time controller and the sampling period and also a trade-off between the two. This paper shows a choice of task for which large sampling periods, necessitating low control gains for maintaining stability, lead to low teleoperation transparency and unacceptable task performance. It continues to show that users can successfully perform the same task if the controller is implemented using analog components. This highlights the advantages of analog haptics in tasks involving the display of highly stiff environments. The paper also highlights the constraints in designing analog haptic teleoperation controllers and proposes design guidelines to address them.     

Nonlinear bilateral teleoperators under event‐driven communication with constant time delays

Bilateral teleoperation systems provide a platform for human operators to remotely manipulate slave robots in engaging various tasks in remote environments. Most of the previous studies in bilateral teleoperation were developed under continuous transmission or periodic communication with fixed data exchanging rates. This paper presents control schemes for bilateral teleoperation systems using nonperiodic event‐driven communication. By using P‐like and PD‐like controllers, this study proposes triggering conditions for teleoperators to reduce network access frequency so that robots only transmit output signals when necessary. Stability and position tracking of the control system are studied, and nonzero minimum interevent time is guaranteed. The proposed event‐driven teleoperation is studied with a velocity estimator to avoid the requirement of velocity information in the controller and triggering condition. Without velocity measurements, the boundedness of tracking errors and stability are ensured for teleoperation systems under event‐driven communication. Simulations and experiments are illustrated to validate the performance of the proposed event‐driven teleoperation systems.     

High‐gain nonlinear observer‐based impedance control for deformable object cooperative teleoperation with nonlinear contact model

Unmeasurable object deformation and local communication time delays between the slave robots influence the manipulation effect for multirobot multioperator teleoperation. In this article, a distributed control method based on high‐gain nonlinear observer, interactive identification, and impedance control is proposed for this problem. First, we use Hunt‐Crossley contact model and deduce the desired synchronizing object state in cooperative teleoperation. Second, an impedance item expressed by the internal position errors is presented to decrease object position tracking errors. For the unmeasurable object deformation, an interactive identification method is proposed for estimating unknown variables. Third, we consider both varying communication time delays and local time delays in the slave side. Two mirror high‐gain nonlinear observers are designed for estimating other slave robots' real‐time state. Finally, we build the system controllers and prove the stability of the closed‐loop system and the boundless of estimating errors using Lyapunov functions. Comparable simulation results executed by the physical system present that the position and internal force tracking errors of the object decrease in the designated cooperative tasks.     

基于多传感器的机器人遥操作人机交互系统

为了增强机器人人机交互系统的自然性,提出了基于多种传感器的非接触式人机交互系统设计方案,系统通过检测操作者手部动作和手部位置姿态的变化实现机器人的遥操作。研制了肌电传感器,获取手臂上一对拮抗肌上的表面肌电信号,并以此来判断机器人操作者的部分手部动作;利用Kinect体感设备和惯性测量单元获取手臂三维位置和姿态角信息。通过网络将人手的动作及位置姿态发送至机器人控制系统,以完成对机器人的控制。系统综合多种传感器的优点,极大减小了传统接触式交互方式对操作者运动范围的限制,实现了自然交互,实验表明了其有效性。     

Haptic tele-driving of wheeled mobile robot over the internet via PSPM approach: theory and experiment

ABSTRACT

We propose novel haptic tele-driving control frameworks of a wheeled mobile robot (WMR) over the imperfect Internet communication network with varying delay and packet loss. We consider both the dynamic and kinematic WMRs and their various tele-driving modes. By utilizing passive set-position modulation framework, we can guarantee two-port passivity or passivity/stability combination of the closed-loop tele-driving system with some theoretical performance measures. Experiments are performed to show the efficacy of the proposed frameworks using the Internet-emulated communication and a custom-built dynamic/kinematic WMR.     

基于时变输出约束的机器人遥操作有限时间控制方法

受操作时间窗口和工作空间的限制,空间遥操作任务需要在有限时间内完成,同时确保末端执行器满足物理约束。此外,时延和外部扰动使不确定遥操作系统的稳定性和控制性能受到严重影响。为此,本文提出了一种基于时变输出约束的机器人遥操作有限时间控制方法。首先,利用积分障碍李雅普诺夫函数处理操作空间的时变约束问题,实用有限时间李雅普诺夫稳定定理保证了系统的快速稳定性。然后,利用神经网络估计环境力以及消解模型不确定性带来的影响,利用鲁棒项补偿神经网络的估计偏差和消解未知外部扰动的影响。最后,在Matlab/Simulink环境下同其他算法进行仿真对比,并在地面实验平台上验证了该算法,理论仿真和实验结果表明该方法进一步提高了误差收敛速率和收敛精度,且系统的输出不会超出预先设定的时变边界。