Motion feedback in the teleoperation of Unmanned Aerial Vehicles

Teleoperation of unmanned vehicles is a valuable tool in scenarios where the operator can not or should not operate the vehicle from on-board. Applications range from hazardous environments where exposure needs to be avoided, control of Unmanned Aerial Vehicles (UAV) to retrieve overviews of inaccessible disaster areas, to deep sea exploration where on-board operation is simply not possible. However, limitations in sensor performance, noise and laten- cies introduced in the transmission, and ineffective display of the information to the operator can lead to a reduced amount of infor- mation, reduced performance, a loss of situation awareness, and in the worst case a loss of the remote vehicle. The spatial decoupling between the operator and the vehicle is one of the main challenges in teleoperation. Most setups include one or more control sticks to steer the ve- hicle, a monitor displaying the live video feed of the main vehicle camera, and a seat for the operator. This can be extended by display- ing additional state information using monitors or visual overlay, rendered on top of the main video stream [Tvaryanas, 2004; van Erp, 2000]. However, processing of multiple screens can increase mental workload. This can cause the operator to miss important information, leading to a loss of situation awareness and reduced performance or a crash of the vehicle. Instead of presenting information purely visually, other feedback modalities can be used to convey vehicle state or information about the task. The goal of this PhD thesis is to investigate the possibility of providing additional information using motion feedback. Here, motion feedback is defined as physically moving the operator using a motion simulator. In the work presented in this thesis a distinction between two motion feedback types is made. Vehicle-state motion feedback describes vehicle motion, while task-related motion feedback is the result of the combination of desired and actual vehicle motion. To investigate the effects of motion feedback in teleoperation several studies have been conducted. In the experiments presented participants either controlled a virtual quadrotor flying in a simu- lated environment or a real octorotor. Participants controlled the UAV from within the CyberMotion Simulator (CMS), an 8-DOF motion simulator located at the Max Planck Institute for Biological Cybernetics. The results show that providing motion feedback has a positive effect on performance in teleoperation of remote UAVs. If the remote vehicle is subject to external disturbances, e.g., wind gusts, vehicle- state feedback showed to improve disturbance rejection capabilities leading to increased performance. Furthermore, motion feedback can be shaped to include additional information about the task with positive effects on performance. This shows that the additional information included in the motion feedback can be used by the operator to improve performance and control behavior.Die Teleoperation eines unbemannten Gefährts ist ein wertvolles Werkzeug in Situationen, in denen der Pilot das Gefährt nicht von Bord aus steuern kann oder sollte. Beispiele hierfür reichen von, für den Piloten, toxischen Umgebungen, über Luftaufnahmen von Katastrophengebieten mithilfe von unbemannten Flugzeugen (engl. Unmanned Aerial Vehicle(UAV)), bis zur Erforschung der Tiefsee, bei der die Steuerung von Bord schlichtweg unmöglich wird. Allerdings führen Einschränkungen in der Sensorerfassung, Rau- schen und Latenzen in der Übertragung, sowie eine ineffiziente Darstellung der Informationen für den Piloten dann zu einem redu- zierten Informationsfluss, reduzierter Leistung, einem Verlust des Situationsbewusstseins und im schlimmsten Fall zu einem Verlust des Gefährts. Die räumliche Entkopplung zwischen dem Piloten und des Flugobjekts ist eine der wichtigsten Herausforderungen in der Teleoperation von UAVs. Die meisten Kontrollstationen beinhalten ein oder mehrere Steu- erknüppel um das Gefährt zu steuern, einen Monitor der eine di- rekte Videoübertragung der Hauptkamera anzeigt und ein Sitzplatz für den Piloten. Dies kann erweitert werden, in dem zusätzliche Statusinformationen mit weiteren Monitoren oder visuellen Über- lagerungen, die über die Hauptübertragung gezeichnet werden, angezeigt werden [Tvaryanas, 2004; van Erp, 2000]. Jedoch kann die Verarbeitung mehrerer Bildschirme die mentale Belastung erhö- hen. Dies kann dazu führen, dass der Pilot wichtige Informationen nicht aufnimmt, was zu einem Verlust des Situationsbewusstseins und einhergehender reduzierten Leistung oder einem Unfall des Gefährts führt. Anstatt Information rein visuell zu präsentieren, können ande- re Modalitäten genutzt werden Rückmeldungen über den Status des Gefährts oder Informationen über die Aufgabe zu präsentieren. Das Ziel dieser Doktorarbeit ist die Untersuchung der Modalität der Bewegung. Es soll untersucht werden, ob Bewegungen genutzt werden können, um dem Piloten zusätzliche Rückmeldungen über den Zustand des Gefährts bereit zu stellen. Bewegungsfeedback beschreibt hier die physikalische Bewegung des Piloten mit Hilfe eines Bewegungssimulators. In dieser Arbeit wird zwischen zwei Typen von Bewegungsfeedback unterschieden. Fahrzeugzustandsbe- wegungsfeedback beschreibt die Bewegung des Fahrzeugs, während Aufgabenabhängiges Bewegungsfeedback die Kombination aus tatsächli- chem und gewünschtem Fahrzeugzustand ist. Die Effekte von Bewegungsfeedback in der Teleoperation wurden in mehreren Studien untersucht. In den vorgestellten Experimenten kontrollierten Teilnehmer entweder einen virtuellen Quadrotor, der in einer simulierten Umgebung flog, oder einen echten Octorotor. Die Teilnehmer steuerten das UAV von der Kanzel des CyberMotion Simulators (CMS) aus, ein 8-DOF Bewegungssimulator, der sich am Max-Planck-Institut für biologische Kybernetik befindet. Die Ergebnisse zeigen, dass die Bereitstellung von Bewegungs- feedback positive Effekte auf die Leistung und das Verhalten des Piloten in der Steuerung des UAVs hat. Ist das UAV externen Stö- rungen ausgesetzt, wie z.B. Windstößen, zeigte sich, dass Fahr- zeugzustandsbewegungsfeedback die Fähigkeit der Störungsunter- drückung des Piloten verbessert, was zu Leistungsteigerungen führt. Außerdem zeigte sich, dass Bewegungsfeedback dahingehend ge- formt werden kann, zusätzliche Informationen über die Aufgabe bereitzustellen. Dies zeigt, dass die zusätzlichen Informationen vom Piloten genutzt werden können um Leistung und Kontrollverhalten zu verbessern

Visual-Vestibular Feedback for Enhanced Situational Awareness in Teleoperation of UAVs

This paper presents a novel concept for improving the situational awareness of a ground operator in remote control of a Unmanned Arial Vehicle (UAV). To this end, we propose to integrate vestibular feedback with the usual visual feedback obtained from a UAV onboard camera. We use our motion platform, the CyberMotion simulator, so as to reproduce online the desired motion cues. We test this architecture by flying a small-scale quadcopter and run a detailed performance evaluation on 12 test subjects. We then discuss the results in terms of possible benefits for facilitating the remote control task

Quality of essential medicines from different sources in Enugu and Anambra, Nigeria

This study investigated the quality of 13 essential medicines in the states of Enugu and Anambra, Nigeria. A total of 260 samples were purchased from licensed pharmaceutical manufacturers and wholesalers and from vendors in pharmaceutical markets with unclear licensing status. Samples were analyzed for identity, content, and dissolution according to the United States Pharmacopeia (USP) 42 monographs. Forty-five samples of this study could be examined for authenticity with the Mobile Authentication Service scheme of the Nigerian National Agency for Food and Drug Administration and Control. Out of all samples, 25.4% did not comply with the USP 42 specifications. Strikingly, 21 out of 22 dexamethasone tablet samples (95%) were out of specification (OOS). Nine out of 19 glibenclamide samples (47%) failed dissolution testing, and 7 out of 17 cotrimoxazole samples (41%) failed assay testing. Medicines against noncommunicable diseases showed a slightly higher percentage of OOS samples than anti-infectives (21.2% versus 17.6%). The rates of OOS samples were similar in medicines stated to be produced in Nigeria, India, and China but were very different between individual manufacturers from each of these countries of origin. Therefore, prequalification of products, manufacturers, and suppliers are very important for quality assurance in medicine procurement. Unexpectedly, the total proportions of OOS samples were similar from licensed vendors (25.2%) and from markets (25.5%). Four samples (1.5%), all collected in markets, were clearly falsified and did not contain the declared active pharmaceutical ingredients. The proportion of falsified medicines was found to be lower than frequently reported in the media for Nigeria

Phenotyping in the era of genomics: MaTrics—a digital character matrix to document mammalian phenotypic traits

A new and uniquely structured matrix of mammalian phenotypes, MaTrics (Mammalian Traits for Comparative Genomics) in a digital form is presented. By focussing on mammalian species for which genome assemblies are available, MaTrics provides an interface between mammalogy and comparative genomics. MaTrics was developed within a project aimed to find genetic causes of phenotypic traits of mammals using Forward Genomics. This approach requires genomes and comprehensive and recorded information on homologous phenotypes that are coded as discrete categories in a matrix. MaTrics is an evolving online resource providing information on phenotypic traits in numeric code; traits are coded either as absent/present or with several states as multistate. The state record for each species is linked to at least one reference (e.g., literature, photographs, histological sections, CT scans, or museum specimens) and so MaTrics contributes to digitalization of museum collections. Currently, MaTrics covers 147 mammalian species and includes 231 characters related to structure, morphology, physiology, ecology, and ethology and available in a machine actionable NEXUS-format*. Filling MaTrics revealed substantial knowledge gaps, highlighting the need for phenotyping efforts. Studies based on selected data from MaTrics and using Forward Genomics identified associations between genes and certain phenotypes ranging from lifestyles (e.g., aquatic) to dietary specializations (e.g., herbivory, carnivory). These findings motivate the expansion of phenotyping in MaTrics by filling research gaps and by adding taxa and traits. Only databases like MaTrics will provide machine actionable information on phenotypic traits, an important limitation to genomics. MaTrics is available within the data repository Morph·D·Base (www.morphdbase.de)

Novel approach for calculating motion feedback in teleoperation

In this paper we present a method for calculating inertial motion feedback in a teleoperation setup. For this we make a distinction between vehicle-state feedback that depends on the physical motion of the remote vehicle, and task-related motion feedback that provides information about the teleoperation task. By providing motion feedback that is independent of vehicle motion we exploit the spatial decoupling between the operator and the controlled vehicle

Effects of vehicle- and task-related motion feedback on operator performance in teleoperation

In this paper we present the results of two experiments performed using a teleoperation setup where operators control a simulated quadrotor in a virtual environment while perceiving visual and inertial motion feedback. Participants of this study performed a series of precision hover tasks. The experiments focused on how different motion feedback definitions affect operator performance and control effort. In the first experiment the effect of including different components of the quadrotor motion in the motion feedback was studied (referred to as "vehicle-related" motion feedback). In the second experiment, the effect of including task-related information in the motion feedback, in the form of a roll motion representing the offset between the desired and actual quadrotor position, was investigated (referred to as "task-related" motion feedback). In both experiments the effects of degraded visual quality was investigated. For both vehicle-related lateral motion feedback and task-related roll motion feedback, we found a significant increase in operator performance. Vehicle-related roll motion feedback showed no effect on operator performance. Control effort, defined as the overall stick deflection during the trials, decreased in vehicle-state roll motion conditions and increased in task-related motion feedback. The results show the applicability and benefits of providing task-related motion feedback in teleoperation