The purpose of simulation is to avoid reality-based constraints by the implemen-tation of a synthetic model. Based on this advantage, interactive simulations have conquered all areas of applications from acquisition, and training, to research. Simulation results are transferred in many ways into reality and conclusions are drawn from the simulation to the application. Many anecdotal observations on human-in-the-loop simulations have shown a significant difference in actor behavior between simulations and reality-based applications. It seems that the factors that makes simulation so attractive, namely the absence of constraints and especially of imminent danger for persons and equipment, influence the behavior and thereby the performance of the user. These differences between simulation and reality may lead to false conclusions based on simulation results. The concept of perceiving a simulation as real and of being in the simulation is called sense of presence. This psychological construct can also be described as level of disbelief towards the simulation. Hence, differences in behavior are based on such users assessment of a simulation and subsequently are supposed to be mediated by a difference in presence. This research established significant differences in presence and performance between a simulation and a miniature-world teleoperation task. Presence and performance changed in identical tasks due to the application type and the connected danger to the robot. Also, the results supported a negative relationship between presence and performance: presence increased in the miniature-world and affected performance so that performance decreased. The causal relationship of application type→ presence→ performance was established and demands the examination of simulation based results with respect to the perceived danger to equipment, before they are transferred into the real application.

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The use of robotics in hazardous environments is becoming more common, where autonomy can handle the dull, dirty and dangerous jobs that humans have previously supported. This thesis focuses on the design of a helicopter deployable unmanned ground vehicle for use in hazardous environments, and presents the benefits of heterogeneous unmanned vehicle teams for operation in beyond line-of-site hazardous environments. The design of a ground robot that is capable of being flown on the undercarriage of a Yamaha RMAX unmanned air vehicle is presented. The robot is size, weight, and power limited and must be capable of traversing rough, unstructured terrain. The results of testing show that the design criteria for size, weight, and mobility are met. A path planning algorithm is developed using the A* search algorithm for the planning of optimal paths through rough terrain. The algorithm makes use of a vehicle/terrain interaction model to compute the cost of path traversal. In the CONOPS, the terrain model is generated real-time during a mission through the use of a stereovision system carried on the helicopter, which station-keeps above the ground robot. The algorithm simulates the robot on the terrain and presents the best feasible path to the operator to aid in teleoperated robot navigation. Simulations of the planning algorithm provided feasible paths over a rough terrain environment. A user study was conducted that evaluates the abilities of both mono- and stereo-vision systems in providing the teleoperator with adequate situational awareness with the intent of proving that stereovision data is more effective at aiding the user in making timely navigation decisions. The results of the study showed that the helicopter-mounted stereovision system was more efficient than the monovision system with respect to navigation time, the number of invalid moves, and total moves required for navigation of a simulated rough terrain environment. / Master of Science

Force feedback during teleoperation and in Virtual Reality (VR) environments is becoming increasingly common. We are interested in understanding the impact of motion on the directional accuracy of force perception, as observed in a VR environment. We used a custom force-feedback system that pulled a handle with a force of 1.87N at various angles in front of N=14 subjects. The virtual environment showed a curved wall, which corresponded to the locations from which the force could physically originate. Subjects selected where they perceived the force to originate from with a virtual laser pointer and by orienting their head. We compared several conditions: the subject held the handle still; the subject moved the handle back and forth toward the center of the wall; the subject moved the handle back and forth across their body; and the subject moved the handle back and forth toward where they thought the force was originating. Subjects were able to localize the force with an average accuracy of 1-10 degrees depending on the force's location, which is better than previous studies. All conditions had similiar accuracies. Subjects had the best precision when they followed the force as compared to either of the other conditions with movement. / Master of Science / In recent years, robots combined with teleoperation, operating in a remote safe environment, has become a popular choice for replacing human workers in dangerous environments. Visual feedback and a sense of touch and motion, are two of the most common feedback modalities. Thus, Virtual Reality (VR) and force rendering are two main ways of conveying information to the operator during teleoperation.\newline Previous studies have investigated the effects of force feedback on the fingers, wrist, and arms but with limited movements and joint combinations. In this paper, we answered the question of how the planar arm movement impacts the force-directional perception accuracy by using a Virtual Reality (VR) system. To put in other words, we want to find out how accurate and precise a robot operator can feel the physical world through joysticks. If they are asked to do this many times in a row, how repeatable are their guesses? To study this, We asked subjects holding a handle made out of PVC pipe with a position sensor on it. The handle was attached to a motor, which pulled the handle away from the subjects during the experiment trial. The experiment consisted of four different conditions, which studied both stationary, when subjects holding the handle stationary and resist the pull by our motor, and movement, when subjects moving the handle in a certain direction while the handle was pulled by our motor. In each trial, subjects were first asked to resist the force according to the experiment condition, then use a laser pointer and head to both point and look at where they think the motor was pulling the handle from. Because of the use of the VR environment and position sensor, subjects reported their guesses intuitively by pointing and looking at, which eliminated the potential of misreporting guesses. The result of this study is important for designing an effective force feedback system for teleoperation. With this information, a force feedback system in a VR environment could be altered to convey information to a user more accurately, for example to correct any biases that the user may have in where they expect forces to originate.\newline Our results show that arm movements enhanced the force feedback precision without sacrificing the accuracy. Arm movements also improved the subjects' confidence level in how well they thought they could localize a force. The results also suggest that pointing with the head is significantly more precise compared with the hand. Such results can be used to implement a more effective force feedback system combined with a VR environment. Finally, our data also shows that hand had an opposite accuracy pattern compared with the head. Future works are needed to explain this opposite accuracy pattern.

The present research is carried out from the viewpoint of primarily space applications where human lives may be in danger if they are to work under these conditions. This work proposes to develop a one-degree-of-freedom (1-DOF) force-reflecting manual controller (FRMC) prototype for teleoperation, and address the effects of time delays commonly found in space applications where the control is accomplished via the earth-based control stations. To test the FRMC, a mobile robot (PPRK) and a slider-bar were developed and integrated to the 1-DOF FRMC. The software developed in Visual Basic is able to telecontrol any platform that uses an SV203 controller through the internet and it allows the remote system to send feedback information which may be in the form of visual or force signals. Time delay experiments were conducted on the platform and the effects of time delay on the FRMC system operation have been studied and delineated.

The goal of this work is to come up with user interface in virtual reality for vehicle robot teleoperation that is equipped with cameras, Velodyne laser distance meter and localization system. The user interface is designed with generally accepted methods for creation of user interfaces in virtual reality. This work also deals with the problem of sickness from VR. The user interface is implemented in Unity3D game engine. The HTC Vive Pro virtual reality kit was used during implementation and testing.

A bilateral teleoperation system makes it possible for a human operator to interact with a remote environment and receive feedback from their actions. In this work, two different teleoperation architectures are studied, one well-established approach called position-force, and another approach called Model-Mediated Teleoperation (MMT). Position-force generates force feedback by measuring forces and sending them over the network, subject to network delay, while MMT generates nondelayed force feedback through a local environment model. The two architectures are compared in terms of transparency (quality of force feedback) and state consistency (equivalence of positions) under different network conditions. Up to 150 ms constant delay in Round Trip Time (RTT) is added. Both architectures are implemented as relatively simple versions of themselves. The case (teleoperation task) under consideration is pushing a cuboid object on a planar surface in a single direction. The MMT architecture is also studied in further detail, in terms of model complexity. Two versions of an MMT model are investigated, one simpler model that has a linear representation of energy loss and one less simple model that has a non-linear representation of energy loss. The purpose is to see what implications there are of increasing or decreasing model complexity. The results indicate that position-force has better performance in terms of both transparency and state consistency than both MMT models for all investigated network conditions. The simple version of MMT (linear model) performs better than the non-linear model, in terms of transparency and state consistency of cuboid positions, for all network conditions except the largest added delay. In terms of state consistency for the device positions, the non-linear model only performs better than the linear model with no added delay. / En distansstyrt system med tvåsidig kommunikation gör det möjligt för en mänsklig operatör att interragera med en avlägsen miljö och få återkoppling. I detta arbete studeras två olika arkitekturer för dessa typer av system. Ett väletablerat tillvägagångssätt som kallas position-force, och ett annat som kallas Model-Mediated Teleoperation (MMT). Position-force genererar kraftåterkoppling genom att mäta krafter och skicka dem över nätverket, utsatt för nätverksfördröjningar, medan MMT genererar en icke-fördröjd kraftåterkoppling från en lokalt modellerad miljö. De två arkitekturerna jämförs med avseende på ”transparency” (kvalitén på kraftåterkopplingen) och ”state consistency” (matchning av positioner) under olika nätverksförhållanden. De studerade förhållandena innefattar upp till 150 ms konstant fördröjning i tur och returtid. Båda arkitekturer implementeras som förhållandevis enkla versioner av sig själva. Det studerade fallet (operatörens uppgift) innefattar puttande på ett rätblock på en plan yta i en enkel riktning. MMT arkitekturen studeras även i vidare detalj med avseende på komplexitet hos den lokala modellen. Två versioner av MMT modellen undersöks, en enklare model som har en linjär representation av energiförlust, och en mer avancerad model som har en icke-linjär representation av energiförlust. Avsikten bakom detta är undersöka vilka implikationer som finns när komplexiteten hos modellen höjs eller sänks. Resultaten indikerar att position-force presterar bättre än MMT med avseende på både transparency och state consistency för alla undersökta nätverksfördröjningar. Den linjära MMT modellen presterar bättre än den icke-linjära modellen, med avseende på transparency och state consistency i rätblockspositioner, för alla nätverksförhållnaden utom den största pålagda fördröjningen. Vidare presterar den icke-linjära modellen bättre än den linjära modellen, med avseende på state consistency för styrande/styrd apparat, endast då ingen nätverksfördröjning läggs på.

Industrial robots have been identified as one of the most effective solutions for optimising output and quality within many industries. However, there are a number of manufacturing applications involving complex tasks and inconstant components which prohibit the use of fully automated solutions in the foreseeable future. A breakthrough in robotic technologies and changes in safety legislations have supported the creation of robots that coexist and assist humans in industrial applications. It has been broadly recognised that human-robot collaborative systems would be a realistic solution as an advanced production system with wide range of applications and high economic impact. This type of system can utilise the best of both worlds, where the robot can perform simple tasks that require high repeatability while the human performs tasks that require judgement and dexterity of the human hands. Robots in such system will operate as “intelligent assistants”. In a collaborative working environment, robot and human share the same working area, and interact with each other. This level of interface will require effective ways of communication and collaboration to avoid unwanted conflicts. This project aims to create a user interface for industrial collaborative robot system through integration of current robotic technologies. The robotic system is designed for seamless collaboration with a human in close proximity. The system is capable to communicate with the human via the exchange of gestures, as well as visual signal which operators can observe and comprehend at a glance. The main objective of this PhD is to develop a Human-Robot Interface (HRI) for communication with an industrial collaborative robot during collaboration in proximity. The system is developed in conjunction with a small scale collaborative robot system which has been integrated using off-the-shelf components. The system should be capable of receiving input from the human user via an intuitive method as well as indicating its status to the user ii effectively. The HRI will be developed using a combination of hardware integrations and software developments. The software and the control framework were developed in a way that is applicable to other industrial robots in the future. The developed gesture command system is demonstrated on a heavy duty industrial robot.

La radiologie interventionnelle est une technique chirurgicale minimallement invasive qui permet d'atteindre des organes à traiter avec des aiguilles, guidées à partir d'images scanner. Bien que cette technique offre de nombreux avantages, l'exposition aux rayons X qu'elle occasionne est nocive pour le radiologue. Pour résoudre ce problème, nous avons développé un système de téléopération avec retour d'efforts. Son cahier des charges a été établi à partir d'expériences in-vivo, qui ont notamment conduit à la modélisation des forces lors d'une insertion. Le système développé répond aux contraintes liées à l'utilisation des rayons X et aux besoins des praticiens. Une étude approfondies a permis de déterminer la commande bilatérale la mieux adaptée à l'application. Pour améliorer la perception des efforts, deux approches ont été étudiées. La première est une synthèse automatique de la commande en effort côté maître. La seconde vise à accroître la sensation de passage entre les tissus.

Most robotic systems reported for MRI-guided prostate interventions use manual needle insertion, based on a previously acquired image, which requires withdrawing the patient from the scanner multiple times during the procedure. This makes the intervention longer, more expensive and elongating the discomfort to patient and, most importantly, less accurate due to the virtually inevitable motion of the target. As a remedy, automated needle placement methods were proposed, putting human supervision out of the control loop. This thesis presents the development of enabling technologies for human-operated in-room master-slave needle placement under real-time MRI guidance, while the patient is kept in the scanner and having the process of needle placement under continuos control of the physician. The feasibility of teleoperated needle insertion was demonstrated by developing a 1-DOF (degree of freedom) MRI-compatible master-slave system, which was integrated with a 4-DOF robot for transperineal prostate biopsy and brachytherapy. An accuracy study was conducted on a robotic system for MRI-guided prostate needle placement. Different error sources were identified and quantified. This study concluded that errors occurring during needle insertion have the most significant contribution to needle placement error. In order to compensate for these errors, teleoperated needle steering under real-time MRI guidance was proposed. A 2-DOF piezo-actuated MRI-compatible needle steering module was developed and integrated with the aforementioned 4-DOF transperineal robot, yielding a fully actuated 6-DOF (x, y, z, yaw, pitch, roll) robotic platform for MRI-guided prostate interventions. A novel MRI-compatible master robot was also developed to enable teleoperated needle steering inside the MRI room. MRI-compatible controller hardware and software were developed. A novel MRI-compatible force/torque sensor was devised using Fiber Bragg Grating for force measurement in MRI room. Phantom experiments proved the feasibility iii of teleoperated needle steering under real-time MRI guidance. A system was also developed for real-time 3D shape tracking of a bevel-tip needle with Fiber Bragg Grating sensors embedded along the needle shaft. The needle profile was overlaid on the real-time MR image, yielding real time navigation with accuracy better than 0.5 mm. The experimental system is presently being refitted for clinical safety and feasibility trials on real patients. / Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2013-05-30 12:26:18.732