PD-like controller with impedance for delayed bilateral teleoperation of mobile robots

This paper proposes a control scheme applied to the delayed bilateral teleoperation of mobile robots with force feedback in face of asymmetric and time-varying delays. The scheme is managed by a velocity PD-like control plus impedance and a force feedback based on damping and synchronization error. A fictitious force, depending on the robot motion and its environment, is used to avoid possible collisions. In addition, the stability of the system is analyzed from which simple conditions for the control parameters are established in order to assure stability. Finally, the performance of the delayed teleoperation system is shown through experiments where a human operator drives a mobile robot.Fil: Slawiñski, Emanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Juan. Instituto de Automática; ArgentinaFil: García, Sebastián Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Juan. Instituto de Automática; ArgentinaFil: Salinas, Lucio Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Juan. Instituto de Automática; ArgentinaFil: Mut, Vicente Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Juan. Instituto de Automática; Argentin

Bilateral Teleoperation of Mobile Robot over Delayed Communication Network: Implementation

In a previous paper we proposed a bilateral teleoperation framework of a wheeled mobile robot over communication channel with constant time delay. In this paper we present experimental results. Our goal is to illustrate and validate the properties of the proposed scheme as well as to present practical implementation issues and the adopted solutions. In particular, the bilaterally teleoperated system is passive and the system is stable in the presence of time delay. Internet has been used as the communication channel and a buffer has been implemented to maintain a constant time delay and to handle packet order

Method to Estimate Human Inattention in Teleoperation of Mobile Robots

In teleoperation of mobile robots the operator is remotely located. As a result, generally the human perception of the remote environment is distorted affecting the mission negatively. Visual information can be degraded because of video images bandwith, time lags, frame rates, point of view and motion effects among other reasons. Although many researchers have proposed a variety of methods for measuring perception, just a few can be used in control closed loop systems. This paper aims to provide a novel metric to the human visual inattention upon risk for a remotely navigated mobile robot. We present both qualitative and quantitative guidelines for designing the metric in a teleoperation of a mobile robot. The method allows to incorporate the metric in a control closed loop system, and task consists in guiding the robot from an initial point to a final one as quick as possible, considering the constraint of avoiding collisions. Furthermore, a haptic cue based on the metric is proposed in order to help the human to avoid collisions. A system stability analysis considering time varying delays is proposed. Additionally, we present a human in the loop experiment of a teleoperation of a 3D mobile robot simulator in order to remark the advantages of using human factors in the controller.Fil: Penizzotto Bacha, Franco Victor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Juan. Instituto de Automática; ArgentinaFil: Mut, Vicente Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Juan. Instituto de Automática; ArgentinaFil: Slawiñski, Emanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Juan. Instituto de Automática; Argentin

Haptic Tele-operation of Wheeled Mobile Robot and Unmanned Aerial Vehicle over the Internet

Teleoperation of ground/aerial vehicle extends operator\u27s ability (e.g. expertise, strength, mobility) into the remote environment, and haptic feedback enhances the human operator\u27s perception of the slave environment. In my thesis, two cases are studied: wheeled mobile robot (MWR) haptic tele-driving over the Internet and unmanned aerial vehicle (UAV) haptic teleoperation over the Internet. We propose novel control frameworks for both dynamic WMR and kinematic WMR in various tele-driving modes, and for a mixed UAV with translational dynamics and attitude kinematics. The recently proposed passive set-position modulation (PSPM) framework is extended to guarantee the passivity and/or stability of the closed-loop system with time-varying/packet-loss in the communication; and proved performance in steady state is shown by theoretical measurements.For UAV teleoperation, we also derive a backstepping trajectory tracking control with robustness analysis. Experimental results for dynamic/kinematic WMR and an indoor quadrotor-type UAV are presented to show the efficacy of the proposed control framework

Stable Bilateral Teleoperation Control Method for Biped Robots with Time-Varying Delays

This document proposes a control scheme applied to delayed bilateral teleoperation of the forward and turn speed of a biped robot against asymmetric and time-varying delays. This biped robot is modeled as a hybrid dynamic system because it behaves as a continuous system when the leg moves forward and discrete when the foot touches the ground generating an impulsive response. It is proposed to vary online the damping according to the time delay present in the communication channel, and the walking cycle time using an optimization criterion, to decrease the teleoperation system errors. To accomplish this, a three-phase cascade calibration process is used, and their benefits are evidenced in a comparative simulation study. The first phase is an offline calibration of the inverse dynamic compensation and also the parameters of the bilateral controller. The second phase guarantees the bilateral coordination of the delayed teleoperation system, using the Lyapunov–Krasovskii stability theory, by changing the leader damping and the equivalent follower damping together. The third phase assures a stable walk of the hybrid dynamics by controlling the walking cycle time and the real damping to move the eigenvalues of the Poincaré map, numerically computed, to stable limit cycles and link this result with an equivalent continuous system to join both phases. Additionally, a fictitious force was implemented to detect and avoid possible collisions with obstacles. Finally, an intercontinental teleoperation experiment of an NAO robot via the Internet including force and visual feedback is shown

Supervising Remote Humanoids Across Intermediate Time Delay

The President's Vision for Space Exploration, laid out in 2004, relies heavily upon robotic exploration of the lunar surface in early phases of the program. Prior to the arrival of astronauts on the lunar surface, these robots will be required to be controlled across space and time, posing a considerable challenge for traditional telepresence techniques. Because time delays will be measured in seconds, not minutes as is the case for Mars Exploration, uploading the plan for a day seems excessive. An approach for controlling humanoids under intermediate time delay is presented. This approach uses software running within a ground control cockpit to predict an immersed robot supervisor's motions which the remote humanoid autonomously executes. Initial results are presented

A Novel Predictor Based Framework to Improve Mobility of High Speed Teleoperated Unmanned Ground Vehicles

Teleoperated Unmanned Ground Vehicles (UGVs) have been widely used in applications when driver safety, mission eciency or mission cost is a major concern. One major challenge with teleoperating a UGV is that communication delays can significantly affect the mobility performance of the vehicle and make teleoperated driving tasks very challenging especially at high speeds. In this dissertation, a predictor based framework with predictors in a new form and a blended architecture are developed to compensate effects of delays through signal prediction, thereby improving vehicle mobility performance. The novelty of the framework is that minimal information about the governing equations of the system is required to compensate delays and, thus, the prediction is robust to modeling errors. This dissertation first investigates a model-free solution and develops a predictor that does not require information about the vehicle dynamics or human operators' motion for prediction. Compared to the existing model-free methods, neither assumptions about the particular way the vehicle moves, nor knowledge about the noise characteristics that drive the existing predictive filters are needed. Its stability and performance are studied and a predictor design procedure is presented. Secondly, a blended architecture is developed to blend the outputs of the model-free predictor with those of a steering feedforward loop that relies on minimal information about vehicle lateral response. Better prediction accuracy is observed based on open-loop virtual testing with the blended architecture compared to using either the model-free predictors or the model-based feedforward loop alone. The mobility performance of teleoperated vehicles with delays and the predictor based framework are evaluated in this dissertation with human-in-the-loop experiments using both simulated and physical vehicles in teleoperation mode. Predictor based framework is shown to provide a statistically significant improvement in vehicle mobility and drivability in the experiments performed.PHDMechanical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/146026/1/zhengys_1.pd

분산형 통신 및 구동부족 로봇시스템 을 위한 분할기법 기반의 반자율 원격제어 프레임워크 개발

학위논문 (박사)-- 서울대학교 대학원 : 공과대학 기계항공공학부, 2018. 2. 이동준.The framework of stable bilateral teleoperation has been well established during decades. However, the standard bilateral teleoperation framework could be a baseline for a successful telerobotics but not sufficient for real-application because they usually concentrate on only the bilateral stability. The least considered in the previous research is how to apply a complex robot systems such as multiple mobile robots or a large degree of freedom mobile manipulators for real applications. The main challenges of teleoperation of complex robotic systems in real-world are to achieve two different control objectives (i.e., follow the human command and the coordination/ stabilization of the internal movement) of the slave robots simultaneously, while providing intuitive information about the complicated features of the system. In this thesis, we develop decomposition-based semi-autonomous teleoperation framework for robotic systems which have distributed communication and underactuation property, consisting of three steps: 1) decomposition step, where the human command is defined, and the robotic system is split into the command tracking space and its orthogonal complement (i.e., internal motion)2) control design of the slave robot, in which we design the slave controller for human command tracking and stabilization/coordination of internal motion spaceand 3) feedback interface design, through which we propose a multi-modal feedback interface (for example, visual and haptic) designed with the consideration of the task and the characteristics of the system. Among numerous types of robots, in this thesis, we focus on two types of robotic systems: 1) multiple nonholonomic wheeled mobile robots (WMRs) with distributed communication requirement and 2) manipulator-stage over vertical flexible beam which is under-actuated system. The proposed framework is applied to both case step by step and perform experiments and human subject study to verify/demonstrate the proposed framework for both cases. For distributed WMRs, we consider the scenario that a single user remotely operates a platoon of nonholonomic WMRs that distributively communicate each other in unknown environment. For this, in decomposition step, we utilize nonholonomic passive decomposition to split the platoon kinematics into that of the formation-keeping aspect and the collective tele-driving aspect. Next, in control design step, we design the controls for these two aspects individually and distribute them into each WMR while fully incorporating their nonholonomic constraint and distribution requirement. Finally, in the step of feedback interface design, we also propose a novel predictive display, which, by providing the user with the estimated current and predicted future pose informations of the platoon and future possibility of collision while fully incorporating the uncertainty inherent to the distribution, can significantly enhance the tele-driving performance and easiness of the platoon. The second part is the manipulator-stage over vertical flexible beam which is under-actuated system. Here, the human command defines the desired motion of the end-effector (or the manipulator), and the vibration of the beam should be subdued at the same time. Thus, at the first step, we utilize the passive decomposition to split the dynamics into manipulator motion space and its orthogonal complement, in which we design the control for the suppression of the vibration. For human command tracking, we design the passivity-based control, and, for the suppression of the vibration, we propose two controls: LQR-based control and nonlinear control based on Lyapunov function analysis. Finally, visuo-haptic feedback interface is preliminarily designed for successful peg-in-hole tasks.1 Introduction 1 1.1 Background and Contribution 1 1.2 Related Works 4 1.2.1 Related Works on Distributed Systems 5 1.2.2 Related Works on Manipulator-Stage System 6 1.3 Outline 6 2 Preliminary 7 2.1 Passive Decomposition 7 2.1.1 Basic Notations and Properties of Standard Passive Decomposition 7 2.1.2 Nonholonomic Passive Decomposition 9 3 Semi-Autonomous Teleoperation of Nonholonomic Wheeled Mobile Robots with Distributed Communication 11 3.1 Distributed Control Design 11 3.1.1 Nonholonomic Passive Decomposition 11 3.1.2 Control Design and Distribution 19 3.2 Distributed Pose Estimation 25 3.2.1 EKF Pose Estimation of Leader WMR 25 3.2.2 EKF Pose Estimation of Follower WMRs 28 3.3 Predictive Display for Distributed Robots Teleoperation 29 3.3.1 Estimation Propagation 31 3.3.2 Prediction Propagation 34 3.4 Experiments 38 3.4.1 Test Setup 38 3.4.2 Performance Experiment 39 3.4.3 Teleoperation Experiment with Predictive Display 40 3.4.4 Human Subject Study 44 4 Semi-Autonomous Teleoperatoin of Stage-Manipulator System on Flexible Vertical Beam 49 4.1 System Modeling 49 4.1.1 System Description 49 4.1.2 Assumed Mode Shapes 51 4.1.3 Exact Solution under Given Boundary Conditions 51 4.1.4 Euler-Lagrangian Equation 61 4.2 LQR-based Control Design 62 4.2.1 Passive Decomposition 63 4.2.2 Vibration Suppression Control Design 64 4.2.3 Joint Tracking Control Design 66 4.3 Lyapunov-based Control Design 68 4.3.1 Twice Passive Decomposition for Input Coupling 69 4.3.2 Interconnected System Description 70 4.3.3 Passivity-based Manipulator Motion Control 74 4.3.4 Dissipative Control for Vibration Suppression 74 4.4 Experiments 78 4.4.1 Test Setup 78 4.4.2 Joint Tracking and Vibration Suppression Experiment 81 4.4.3 Comparison Experiment between the LQR and the Nonlinear Control 82 5 Conclusion 83 5.1 Summary 83 5.2 Future Works 83 A Appendix 85 A.1 Internal Wrench Representation 85Docto