In recent years, teleoperation has shown great potentials in different fields such as spatial, mining, under-water, etc. When teleoperation is required to be bilateral, the time delay induced by a potentially large physical distance prevents a good performance of the controller, especially in case of contact. When bilateral teleoperation is introduced to the field of medicine, a new challenge arises: the controller needs to be used in both hard and soft environments. For example, in the context of telesurgery, the robot can enter in contact with both bone (hard) and organ (soft). In an attempt to enrich existing controller designs to better suit the medical needs, an adaptive fuzzy logic controller is designed in this text. It simulates human intelligence and adapts the controller to environments of different stiffness coefficients. It is compared to three other classical controllers used in the field of bilateral teleopeartion and demonstrates very interesting potential.

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.

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The Compact Rescue Crawler is a pneumatic legged robot. Two legs of a hexapod were designed and built. The legs are controlled directly from operator inputs. The operator gives foot position inputs through two PHANToM haptic controllers. A PD controller with a supplementary force gain-scheduler control stroke lengths of each cylinder. The force-based position control technique allows the robot feet to track operator inputs to within 10% position error. A guided gait algorithm was developed to allow the operator to control all 6 legs simply by haptically guiding the front two. The operator records successful and collision-free trajectories and the gait coordinator plays the trajectories through the rear legs as they approach the detected obstacles. This hybrid gait algorithm allows the robot to proceed through a hazardous environment, guided by an operator, but without taxing the input capabilities of the human operator.