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While the robots gradually become a part of our daily lives, they already play vital roles in many critical operations. Some of these critical tasks include surgeries, battlefield operations, and tasks that take place in hazardous environments or distant locations such as space missions. In most of these tasks, remotely controlled robots are used instead of autonomous robots. This special area of robotics is called teleoperation. Teleoperation systems must be reliable when used in critical tasks; hence, all of the subsystems must be dependable even under a subsystem or communication line failure. These systems are categorized as unilateral or bilateral teleoperation. A special type of bilateral teleoperation is described as force-reflecting teleoperation, which is further investigated as limited- and unlimited-workspace teleoperation. Teleoperation systems configured in this study are tested both in numerical simulations and experiments. A new method, Virtual Rapid Robot Prototyping, is introduced to create system models rapidly and accurately. This method is then extended to configure experimental setups with actual master systems working with system models of the slave robots accompanied with virtual reality screens as well as the actual slaves. Fault-tolerant design and modeling of the master and slave systems are also addressed at different levels to prevent subsystem failure. Teleoperation controllers are designed to compensate for instabilities due to communication time delays. Modifications to the existing controllers are proposed to configure a controller that is reliable in communication line failures. Position/force controllers are also introduced for master and/or slave robots. Later, controller architecture changes are discussed in order to make these controllers dependable even in systems experiencing communication problems. The customary and proposed controllers for teleoperation systems are tested in numerical simulations on single- and multi-DOF teleoperation systems. Experimental studies are then conducted on seven different systems that included limited- and unlimited-workspace teleoperation to verify and improve simulation studies. Experiments of the proposed controllers were successful relative to the customary controllers. Overall, by employing the fault-tolerance features and the proposed controllers, a more reliable teleoperation system is possible to design and configure which allows these systems to be used in a wider range of critical missions.

Dieser Beitrag zeigt ein umgesetztes Gesamtkonzept für eine manuelle und kollisionsfreie Telemanipulation von Industrierobotern basierend auf einem digitalen Zwilling. Als Demonstrator dient hierfür ein Aufbau, mit dem eine manuelle Pick-and-Place-Applikation exemplarisch nachgebildet wird. Der manuell gesteuerte Industrieroboter soll kleine, mit Flüssigkeit befüllten Glasfläschchen (sogenannten Vials) aufnehmen, transportieren und an einen definierten Ablageort kollisionsfrei absetzten. In diesem Beitrag werden sämtliche notwendigen Schritte nachvollziehbar dargestellt und erläutert. Die Definition und Realisierung des digitalen Zwillings, die Gestaltungsmöglichkeiten des Arbeitsraums und dessen Überwachung sowie die Kollisionsüberprüfung sollen hierbei die Schwerpunkte darstellen. Außerdem werden die notwendigen Systemvoraussetzungen Umsetzung des Konzepts dargestellt. Die eigentliche Bewegungssteuerung des Industrieroboters wird mit unterschiedlichen Manipulatoren verifiziert.

In diesem Beitrag wird die IDEA-Box MC (Industrial Digitalization in Education of Automation – Motion Control) und die damit realisierbaren Anwendungsmöglichkeiten und vermittelbaren Lerninhalte vorgestellt. Neben dem mechanischen Aufbau werden die unterschiedlichen Möglichkeiten und Methoden im Bereich der Positioniertechnik von mechatronischen Systemen, die sich heutzutage mit speicherprogrammierbaren Steuerungen realisieren lassen, vorgestellt. Dabei werden neben einfachen Rast-in-Rast Bewegungen von Einzelachsen, vor allem das resonanzfreie Positionieren von schwingungsfähigen Systemen und synchronisierten Mehrachssystemen im Kurvenscheibenverbund (integrierte und synchronisierte Robotik) aufgezeigt und beschrieben. Außerdem wird aufgeführt, dass mithilfe eines digitalen Zwillings kollisionsfreie Telemanipulation realisiert werden kann.

Hydraulic manipulators commonly interact with environments that are highly unstructured, and thus rely on the intelligence of human operators to provide proper commands. Typically, operators use visual information, directly or through cameras, to perform a task. Providing haptic or touch sensation about the task environment to the operator, enhances her/his ability to perform telemanipulation. The focus of this thesis is on haptic teleoperation of hydraulic manipulators. The application is directed at live transmission line maintenance tasks. In this thesis, both unilateral and bilateral haptic teleoperation of hydraulic manipulators are investigated. On the unilateral telemanipulation front, position error is shown to be an important issue in performing repetitive tasks. The most important sources of inaccuracy in position are sensors, robot controller performance, and the operator. To reduce the human operator’s errors, the concept of virtual fixtures is adopted in this research. It is shown that virtual fixtures can help operators perform routine tasks related to live line maintenance. Stability and telepresence are the main issues in reference to bilateral control. Three stable bilateral control schemes are designed for haptic teleoperation of hydraulic actuators considering nonlinear dynamics of hydraulic actuation, haptic device, and the operator. For each control scheme, stability of the entire control system is proven theoretically by constructing a proper Lyapunov function. Due to the discontinuity originating from a sign function in the control laws, the proposed control systems are non-smooth. Thus, the existence, continuation, and uniqueness of Filippov’s solution to the system are first proven for each control system. Next, the extensions of Lyapunov’s stability theory to non-smooth systems and LaSalle’s invariant set theorems are employed to prove the asymptotic stability of the control systems. In terms of telepresence, two types of haptic sensation are provided to the operator: (i) haptic based on the reflected interaction force, and (ii) haptic based on the position error. Performances of all proposed controllers are validated by experimental results on a hydraulic actuator controlled by a haptic device. It is shown that besides stability, the hydraulic actuator performs well in terms of position tracking while the haptic device provides telepresence for the operator.

Hydraulic manipulators commonly interact with environments that are highly unstructured, and thus rely on the intelligence of human operators to provide proper commands. Typically, operators use visual information, directly or through cameras, to perform a task. Providing haptic or touch sensation about the task environment to the operator, enhances her/his ability to perform telemanipulation. The focus of this thesis is on haptic teleoperation of hydraulic manipulators. The application is directed at live transmission line maintenance tasks. In this thesis, both unilateral and bilateral haptic teleoperation of hydraulic manipulators are investigated. On the unilateral telemanipulation front, position error is shown to be an important issue in performing repetitive tasks. The most important sources of inaccuracy in position are sensors, robot controller performance, and the operator. To reduce the human operator’s errors, the concept of virtual fixtures is adopted in this research. It is shown that virtual fixtures can help operators perform routine tasks related to live line maintenance. Stability and telepresence are the main issues in reference to bilateral control. Three stable bilateral control schemes are designed for haptic teleoperation of hydraulic actuators considering nonlinear dynamics of hydraulic actuation, haptic device, and the operator. For each control scheme, stability of the entire control system is proven theoretically by constructing a proper Lyapunov function. Due to the discontinuity originating from a sign function in the control laws, the proposed control systems are non-smooth. Thus, the existence, continuation, and uniqueness of Filippov’s solution to the system are first proven for each control system. Next, the extensions of Lyapunov’s stability theory to non-smooth systems and LaSalle’s invariant set theorems are employed to prove the asymptotic stability of the control systems. In terms of telepresence, two types of haptic sensation are provided to the operator: (i) haptic based on the reflected interaction force, and (ii) haptic based on the position error. Performances of all proposed controllers are validated by experimental results on a hydraulic actuator controlled by a haptic device. It is shown that besides stability, the hydraulic actuator performs well in terms of position tracking while the haptic device provides telepresence for the operator.

The research addresses current shortcomings of autonomous service robots operating in domestic environments by considering the concept of a semi-autonomous robot that would be supported by human remote operators whenever the robot cannot handle a task autonomously. The main research objective was to investigate how to design the human-robot interaction for a robotic system to assist elderly people with physical tasks at home according to this conceptual idea. The research procedure followed the principles of human-centered design and is structured into four phases: In the first phase, the context of use of the system to be designed was determined. A focus group study yielded characteristics and attitudes of several potential user groups. A survey determined the demands of elderly people and informal caregivers for services a semiautonomous assistive robot may provide. An ethnographic study investigated the living conditions of elderly people and determined technical challenges for robots operating in this type of environment. Another ethnographic study investigated the work environment in teleassistive service centers and determined the feasibility of extending their range of services to incorporate robotic teleassistance. In the second phase, two studies were carried out to understand the interaction requirements. The first study determined common types of failure of current autonomous robots and required human interventions to resolve such failure states. The second study investigated how the human assistance could be provided considering a range of potential interaction devices. In the third phase, a human-robot interaction concept with three user groups and dedicated user interfaces was designed. The concept and user interfaces were refined in an iterative process based on the results of evaluations with prospective users and received encouraging results for user satisfaction and user experience. In the fourth and final phase the utility of two specific user interface features was investigated experimentally. The first experiment investigated the utility of providing remote operators with global 3D environment maps during robot navigation and identified beneficial usage scenarios. The second experiment investigated the utility of stereoscopic display for remote manipulation and robot navigation. Results suggested temporal advantages under stereoscopic display for one of three investigated task types and potential advantages for the other two. / Forskningen behandlar problem med autonoma robotar som agerar i hemmiljö. Specifikt studeras konceptet semi-autonoma robotar, vilket innebär att robotarna stöds av mänskliga operatörer när de inte klarar uppgifter på egen hand. Syftet med forskningen är att undersöka design av människa-robotinteraktion för robotsystem som stöder äldres behov av hjälp med fysiska uppgifter i hemmiljö. Forskningen är användarcentrerad och har strukturerats i fyra faser: I den första fasen undersöktes användarkontexten för systemet. I en fokusgruppsstudie utforskades karakteristika och attityder för flera potentiella användargrupper. Kraven på en semi-autonom robot för att assistera äldre och informella vårdgivare fastställdes. En enkätstudie undersökte levnadsvillkor hos äldre för att utforska tekniska utmaningar dessa omgivningar ställer på robotar. En etnografisk studie undersökte arbetskontexten på servicecenter för teleassistans och undersökte genomförbarhet i att utöka tjänsteutbudet till att även inkludera teleassisterade robotar. I den andra fasen utfördes två studier för att få kunskap om interaktionskrav. Den första studien fastställde vanliga typer av fel som inträffar med nuvarande typer av autonoma robotar och de typer av mänsklig assistans som krävs för att hantera dessa fel. Den andra studien undersökte hur mänsklig assistans kan utformas givet en repertoar av potentiella interaktionsanordningar. I den tredje fasen utformades ett interaktionskoncept för människa-robot interaktionen för tre användargrupper med dedicerade gränssnitt. Koncepten och användargränssnitten förfinades i en iterativ process baserat på resultat från utvärderingar med tänkta användare, och resulterade i uppmuntrande resultat vad gäller användarnas uppskattning och tillfredsställelse. I den fjärde och sista fasen studerades nyttan hos två specifika gränssnitt experimentellt. Det första experimentet undersökte nyttan med att ge operatörer på distans globala 3D-kartor under robotnavigeringen och identifierade användarscenarier där detta kan utnyttjas. Det andra experimentet undersökte nyttan med en stereoskopisk display för att manipulera och navigera roboten på distans. Resultaten visar på temporala fördelar med stereoskopisk display för en av tre undersökta uppgiftstyper och potentiella fördelar för de andra två.