External force estimation for telerobotics without force sensor

This paper establishes an approach to external force estimation through the use of a mathematical model and current sensing, without employing a force/torque sensor. The advantages and need for force feedback have been well established in the field of telerobotics. This paper presents the requirement for sensorless force estimation and comparative results between a force sensor and the presented approach using an industrial robot. The approach presents not only a cost effective solution but also a solution for force sensing in hazardous environments, especially ionizing radiation prone environments where the dose rates limit the use of sensing equipment. The paper also discusses the applications and advantages presented by this work in various fields

Master-Slave Coordination Using Virtual Constraints for a Redundant Dual-Arm Haptic Interface

Programming robots for tasks involving force interaction is difficult, since both the knowledge of the task and the dynamics of the robots are necessary. An immersive haptic interface for task demonstration is proposed, where theoperator can sense and act through the robot. This is achieved by coupling two robotic systems with virtual constraints such that they have the same coordinates in the operational space disregarding a fixed offset. Limitations caused by the singular configurations or the reach of the robots are naturally reflected to either side as haptic feedback

Teleoperation of industrial robot manipulators based on augmented reality

This research develops a novel teleoperation for robot manipulators based on augmented reality. The proposed interface is equipped with full capabilities in order to replace the classical teach pendant of the robot for carrying out teleoperation tasks. The proposed interface is based on an augmented reality headset for projecting computer-generated graphics onto the real environment and a gamepad to interact with the computer-generated graphics and provide robot commands. In order to demonstrate the benefits of the proposed method, several usability tests were conducted using a 6R industrial robot manipulator in order to compare the proposed interface and the conventional teach pendant interface for teleoperation tasks. In particular, the results of these usability tests show that the proposed approach is more intuitive, ergonomic, and easy to use. Furthermore, the comparison results also show that the proposed method clearly improves the velocity of the teleoperation task, regardless of the user's previous experience in robotics and augmented reality technology

Remote lab of robotic manipulators through an open access ROS-based platform

The research, training, and learning in robotic systems is a difficult task for institutions that do not have an appropriate equipment infrastructure, mainly due to the high investment required to acquire these systems. Possible alternatives are the use of robotic simulation platforms and the creation of remote robotic environments available for different users. The use of the last option surpasses the former one in terms of the possibility to handle real robotic systems during the training process. However, technical challenges appear in the management of the supporting infrastructure to use the robotic systems, namely in terms of access, safety, security, communication, and programming aspects. Having this in mind, this paper presents an approach for the remote operation of real robotic manipulators under a virtual robotics laboratory. To this end, an open access and safe web-based platform was developed for the remote control of robotic manipulators, being validated through the remote control of a real UR3 manipulator. This platform contributes to the research and training in robotic systems among different research centers and educational institutions that have limited access to these technologies. Furthermore, students and researchers can use this educational tool that differs from traditional robotic simulators through a virtual experience that connects real manipulators worldwide through the Internet.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI (UIDB/05757/2020 and UIDP/05757/2020), and SusTEC (LA/P/0007/2021).info:eu-repo/semantics/publishedVersio

Hardware-in-the-Loop Simulation for Evaluating Communication Impacts on the Wireless-Network-Controlled Robots

More and more robot automation applications have changed to wireless communication, and network performance has a growing impact on robotic systems. This study proposes a hardware-in-the-loop (HiL) simulation methodology for connecting the simulated robot platform to real network devices. This project seeks to provide robotic engineers and researchers with the capability to experiment without heavily modifying the original controller and get more realistic test results that correlate with actual network conditions. We deployed this HiL simulation system in two common cases for wireless-network-controlled robotic applications: (1) safe multi-robot coordination for mobile robots, and (2) human-motion-based teleoperation for manipulators. The HiL simulation system is deployed and tested under various network conditions in all circumstances. The experiment results are analyzed and compared with the previous simulation methods, demonstrating that the proposed HiL simulation methodology can identify a more reliable communication impact on robot systems.Comment: 6 pages, 11 figures, to appear in 48th Annual Conference of the Industrial Electronics Society IECON 2022 Conferenc

Quality-Latency Trade-Off in Bilateral Teleoperation

The purpose of this thesis is to investigate how the latency in mobile networks affect the quality of highly demanding and sensitive applications running on it. Furthermore, this thesis will provide some information to what is going on in the field of Cloud Computing and the Internet of Things. It will hopefully spark a discussion about what possibilities will come with the development of the Cloud and Internet of Things. The application chosen was a bilateral teleoperation, with force feedback, controlled in 6 dimensions. To investigate how the quality depends on network latency, different network models were simulated as the communication channel. The networks chosen to be simulated were a 3G, 4G, and a 5G cellular network along with a wired network chosen as a baseline. On this setup two main experiments were done. The first one was a collision test and the second one a dexterity test, where a user was supposed to pick up a small wooden brick and put it into a box. The results from the experiments showed that there was indeed a difference in behavior when having a network delay larger than 20 ms

Trajectory Generation for Assembly Tasks Via Bilateral Teleoperation

Abstract in UndeterminedFor assembly tasks, the knowledge of both trajectory and forces are usually required. Consequently, we may use kinesthetics or teleoperation for recording human demonstrations. In order to have a more natural interaction, the operator has to be provided with a sense of touch. We propose a bilateral teleoperation system which is customized for this purpose. We introduce different coordinate frames to make the design of a 6-DOF teleoperation straightforward. Moreover, we suggest using tele-admittance, which simplifies instructing the robot. The compliance due to the slave controller allows the robot to react quickly and reduces the risk of damaging the workpiece

Hand-Gesture Based Programming of Industrial Robot Manipulators

Nowadays, industrial robot manipulators and manufacturing processes are associated as never before. Robot manipulators execute repetitive tasks with increased accuracy and speed, features necessary for industries with needs for manufacturing of products in large quantities by reducing the production time. Although robot manipulators have a significant role for the enhancement of productivity within industries, the programming process of the robot manipulators is an important drawback. Traditional programming methodologies requires robot programming experts and are time consuming. This thesis work aims to develop an application for programming industrial robot manipulators excluding the need of traditional programing methodologies exploiting the intuitiveness of humans’ hands’ gestures. The development of input devices for intuitive Human-Machine Interactions provides the possibility to capture such gestures. Hence, the need of the need of robot manipulator programming experts can be replaced by task experts. In addition, the integration of intuitive means of interaction can reduce be also reduced. The components to capture the hands’ operators’ gestures are a data glove and a precise hand-tracking device. The robot manipulator imitates the motion that human operator performs with the hand, in terms of position. Inverse kinematics are applied to enhance the programming of robot manipulators in-dependently of their structure and manufacturer and researching the possibility for optimizing the programmed robot paths. Finally, a Human-Machine Interface contributes in the programming process by offering important information for the programming process and the status of the integrated components

A sensorless virtual slave control scheme for kinematically dissimilar master-slave teleoperation

The use of telerobotic systems is essential for remote handling (RH) operations in radioactive areas of scientific facilities that generate high doses of radiation. Recent developments in remote handling technology has seen a great deal of effort being directed towards the design of modular remote handling control rooms equipped with a standard master arm which will be used to separately control a range of different slave devices. This application thus requires a kinematically dissimilar master-slave control scheme. In order to avoid drag and other effects such as friction or other non-linear and unmodelled slave arm effects of the common position-position architecture in nonbackdrivable slaves, this research has implemented a force-position control scheme. End-effector force is derived from motor torque values which, to avoid the use of radiation intolerant and costly sensing devices, are inferred from motor current measurement. This has been demonstrated on a 1-DOF test-rig with a permanent magnet synchronous motor teleoperated by a Sensable Phantom Omni® haptic master. This has been shown to allow accurate control while realistically conveying dynamic force information back to the operator