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  • 1.
    Aarno, Daniel
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP. KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS.
    Ekvall, Staffan
    KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP. KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS.
    Kragic, Danica
    KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP. KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS.
    Adaptive virtual fixtures for machine-assisted teleoperation tasks2005Ingår i: 2005 IEEE International Conference on Robotics and Automation (ICRA), Vols 1-4, 2005, s. 1139-1144Konferensbidrag (Refereegranskat)
    Abstract [en]

    It has been demonstrated in a number of robotic areas how the use of virtual fixtures improves task performance both in terms of execution time and overall precision, [1]. However, the fixtures are typically inflexible, resulting in a degraded performance in cases of unexpected obstacles or incorrect fixture models. In this paper, we propose the use of adaptive virtual fixtures that enable us to cope with the above problems. A teleoperative or human machine collaborative setting is assumed with the core idea of dividing the task, that the operator is executing, into several subtasks. The operator may remain in each of these subtasks as long as necessary and switch freely between them. Hence, rather than executing a predefined plan, the operator has the ability to avoid unforeseen obstacles and deviate from the model. In our system, the probability that the user is following a certain trajectory (subtask) is estimated and used to automatically adjusts the compliance. Thus, an on-line decision of how to fixture the movement is provided.

  • 2.
    Aarno, Daniel
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS. KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP.
    Kragic, Danica
    KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS. KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP.
    Layered HMM for motion intention recognition2006Ingår i: 2006 IEEE/RSJ International Conference on Intelligent Robots and Systems, Vols 1-12, NEW YORK: IEEE , 2006, s. 5130-5135Konferensbidrag (Refereegranskat)
    Abstract [en]

    Acquiring, representing and modeling human skins is one of the key research areas in teleoperation, programming. by-demonstration and human-machine collaborative settings. One of the common approaches is to divide the task that the operator is executing into several subtasks in order to provide manageable modeling. In this paper we consider the use of a Layered Hidden Markov Model (LHMM) to model human skills. We evaluate a gestem classifier that classifies motions into basic action-primitives, or gestems. The gestem classifiers are then used in a LHMM to model a simulated teleoperated task. We investigate the online and offline classilication performance with respect to noise, number of gestems, type of HAIM and the available number of training sequences. We also apply the LHMM to data recorded during the execution of a trajectory-tracking task in 2D and 3D with a robotic manipulator in order to give qualitative as well as quantitative results for the proposed approach. The results indicate that the LHMM is suitable for modeling teleoperative trajectory-tracking tasks and that the difference in classification performance between one and multi dimensional HMMs for gestem classification is small. It can also be seen that the LHMM is robust w.r.t misclassifications in the underlying gestem classifiers.

  • 3.
    Abdul Khader, Shahbaz
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Data-Driven Methods for Contact-Rich Manipulation: Control Stability and Data-Efficiency2021Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Autonoma robotar förväntas utgöra en allt större närvaro på människors arbetsplatser och i deras hem. Till skillnad från sina industriella motparter, behöver dessa autonoma robotar hantera en stor mängd osäkerhet och brist på struktur i sina omgivningar. En väsentlig del av att utföra manipulation i dylika scenarier, är förekomsten av fysisk interaktion med direkt kontakt mellan roboten och dess omgivning. Därför måste robotar, inte olikt människor, kunna hantera både förväntade och oväntade kontakter med omgivningen, som ofta karaktäriseras av komplex interaktionsdynamik.

    Skill learning, eller inlärning av färdigheter, står ut som ett lovande alternativ för att låta robotar tillgodogöra sig en rik förmoga att generera rörelser. I Skill Learning används datadrivna metoder för att lära in en reaktiv policy, en reglerfunktion som kopplar tillstånd till styrsignaler. Detta tillvägagångssätt är tilltalande eftersom en tillräckligt uttrycksfull policy kan generera lämpliga styrsignaler nästan instantant, utan att behöva genomföra beräkningsmässigt kostsamma sökoperationer. Även om Reinforcement Learning (RL), förstärkningsinlärning, är ett naturligt ramverk för skill learning, har dess praktiska tillämpningar varit begräsade av ett antal anledningar. Det kan med fog påstås att de två främsta anledningarna är brist på garanterad stabilitet, och dålig dataeffektivitet. Stabilitet i reglerloopen är nödvändigt för att kunna garanterar säkerhet och förutsägbarhet, och dataeffektivitet behövs för att uppnå realistiska inlärningstider. I denna avhandling söker vi efter lösningar till dessa problem i kontexten av manipulation med rik förekomst av kontakter.

    Denna avhandling behandlar först problemet med stabilitet. Trots at dynamiken för interaktionen är okänd vid förekomsten av kontakter, formuleras skill learning med stabilitetsgarantier som ett modelfritt RL-problem. Avhandlingen presenterar flera lösningar för att parametrisera stabilitetsmedvetna policys. Detta följs sedan av lösningar för att söka efter policys som är stabila under slumpmässig sökning, om detta behövs. Några parametriseringar bestå helt eller delvis av djupa neurala nätverk. I ett fall introduceras också en sökmetod baserad på evolution strategies. Vi visar, genom experiment på faktiska robotar, att lyaponovstabilitet är både möjligt och fördelaktigt vid RL-baserad skill learning.

    Vidare tar avhandlingen upp dataeffektivitet. Även om dataeffektiviteten angrips genom att formulera skill learning som ett modellbaserat RL-problem, så behandlar vi endast delen med modellinlärning. Utöver att dra nytta av dataeffektiviteten och osäkerhetsrepresentationen i gaussiska processer, så undersöker avhandlingen även fördelarna med att använda strukturen hos hybrida automata för att lära in modeller för framåtdynamiken. Metoden innehåller även en algoritm för att förutsäga fördelningarna av trajektorier över en längre tidsrymd, för att representera diskontinuiteter och multipla moder. Vi visar att den föreslagna metodiken är mer dataeffektiv än ett antal existerande metoder.

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  • 4.
    Abdul Khader, Shahbaz
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Yin, Hang
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Falco, Pietro
    ABB Corporate Research, Vasteras, 72178, Sweden.
    Kragic, Danica
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL. ABB Corporate Research, Vasteras, 72178, Sweden.
    Learning deep energy shaping policies for stability-guaranteed manipulation2021Ingår i: IEEE Robotics and Automation Letters, E-ISSN 2377-3766, Vol. 6, nr 4, s. 8583-8590Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Deep reinforcement learning (DRL) has been successfully used to solve various robotic manipulation tasks. However, most of the existing works do not address the issue of control stability. This is in sharp contrast to the control theory community where the well-established norm is to prove stability whenever a control law is synthesized. What makes traditional stability analysis difficult for DRL are the uninterpretable nature of the neural network policies and unknown system dynamics. In this work, stability is obtained by deriving an interpretable deep policy structure based on the energy shaping control of Lagrangian systems. Then, stability during physical interaction with an unknown environment is established based on passivity. The result is a stability guaranteeing DRL in a model-free framework that is general enough for contact-rich manipulation tasks. With an experiment on a peg-in-hole task, we demonstrate, to the best of our knowledge, the first DRL with stability guarantee on a real robotic manipulator.

  • 5.
    Abdul Khader, Shahbaz
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Yin, Hang
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Falco, Pietro
    Kragic, Danica
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL. KTH, Skolan för elektroteknik och datavetenskap (EECS), Centra, Centrum för autonoma system, CAS.
    Learning Deep Neural Policies with Stability GuaranteesManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Deep reinforcement learning (DRL) has been successfully used to solve various robotic manipulation tasks. However, most of the existing works do not address the issue of control stability. This is in sharp contrast to the control theory community where the well-established norm is to prove stability whenever a control law is synthesized. What makes traditional stability analysis difficult for DRL are the uninterpretable nature of the neural network policies and unknown system dynamics. In this work, unconditional stability is obtained by deriving an interpretable deep policy structure based on the energy shaping control of Lagrangian systems. Then, stability during physical interaction with an unknown environment is established based on passivity. The result is a stability guaranteeing DRL in a model-free framework that is general enough for contact-rich manipulation tasks. With an experiment on a peg-in-hole task, we demonstrate, to the best of our knowledge, the first DRL with stability guarantee on a real robotic manipulator.

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  • 6.
    Abdul Khader, Shahbaz
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL. ABB Corp Res, Västerås, Sweden..
    Yin, Hang
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Falco, Pietro
    ABB Corp Res, Västerås, Sweden..
    Kragic, Danica
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Learning Stable Normalizing-Flow Control for Robotic Manipulation2021Ingår i: 2021 IEEE International Conference On Robotics And Automation (ICRA 2021), Institute of Electrical and Electronics Engineers (IEEE) , 2021, s. 1644-1650Konferensbidrag (Refereegranskat)
    Abstract [en]

    Reinforcement Learning (RL) of robotic manipulation skills, despite its impressive successes, stands to benefit from incorporating domain knowledge from control theory. One of the most important properties that is of interest is control stability. Ideally, one would like to achieve stability guarantees while staying within the framework of state-of-the-art deep RL algorithms. Such a solution does not exist in general, especially one that scales to complex manipulation tasks. We contribute towards closing this gap by introducing normalizing-flow control structure, that can be deployed in any latest deep RL algorithms. While stable exploration is not guaranteed, our method is designed to ultimately produce deterministic controllers with provable stability. In addition to demonstrating our method on challenging contact-rich manipulation tasks, we also show that it is possible to achieve considerable exploration efficiency-reduced state space coverage and actuation efforts- without losing learning efficiency.

  • 7.
    Abdul Khader, Shahbaz
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Yin, Hang
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Pietro, Falco
    Kragic, Danica
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL. KTH, Skolan för elektroteknik och datavetenskap (EECS), Centra, Centrum för autonoma system, CAS.
    Learning Stable Normalizing-Flow Control for Robotic ManipulationManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Reinforcement Learning (RL) of robotic manipu-lation skills, despite its impressive successes, stands to benefitfrom incorporating domain knowledge from control theory. Oneof the most important properties that is of interest is controlstability. Ideally, one would like to achieve stability guaranteeswhile staying within the framework of state-of-the-art deepRL algorithms. Such a solution does not exist in general,especially one that scales to complex manipulation tasks. Wecontribute towards closing this gap by introducing normalizing-flow control structure, that can be deployed in any latest deepRL algorithms. While stable exploration is not guaranteed,our method is designed to ultimately produce deterministiccontrollers with provable stability. In addition to demonstratingour method on challenging contact-rich manipulation tasks, wealso show that it is possible to achieve considerable explorationefficiency–reduced state space coverage and actuation efforts–without losing learning efficiency.

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  • 8. Agarwal, Priyanshu
    et al.
    Al Moubayed, Samer
    KTH, Skolan för datavetenskap och kommunikation (CSC), Robotik, perception och lärande, RPL.
    Alspach, Alexander
    Kim, Joohyung
    Carter, Elizabeth J.
    Lehman, Jill Fain
    Yamane, Katsu
    Imitating Human Movement with Teleoperated Robotic Head2016Ingår i: 2016 25TH IEEE INTERNATIONAL SYMPOSIUM ON ROBOT AND HUMAN INTERACTIVE COMMUNICATION (RO-MAN), 2016, s. 630-637Konferensbidrag (Refereegranskat)
    Abstract [en]

    Effective teleoperation requires real-time control of a remote robotic system. In this work, we develop a controller for realizing smooth and accurate motion of a robotic head with application to a teleoperation system for the Furhat robot head [1], which we call TeleFurhat. The controller uses the head motion of an operator measured by a Microsoft Kinect 2 sensor as reference and applies a processing framework to condition and render the motion on the robot head. The processing framework includes a pre-filter based on a moving average filter, a neural network-based model for improving the accuracy of the raw pose measurements of Kinect, and a constrained-state Kalman filter that uses a minimum jerk model to smooth motion trajectories and limit the magnitude of changes in position, velocity, and acceleration. Our results demonstrate that the robot can reproduce the human head motion in real time with a latency of approximately 100 to 170 ms while operating within its physical limits. Furthermore, viewers prefer our new method over rendering the raw pose data from Kinect.

  • 9. Aguiar, Miguel
    et al.
    Estrela da Silva, Jorge
    Borges de Sousa, João
    Minimal time delivery of multiple robots2020Ingår i: 2020 59th IEEE Conference on Decision and Control (CDC), 2020Konferensbidrag (Refereegranskat)
    Abstract [en]

    Consider a set of autonomous vehicles, each one with a preassigned task to start at a given region. Due to energy constraints, and in order to minimize the overall task completion time, these vehicles are deployed from a faster carrier vehicle. This paper develops a dynamic programming (DP) based solution for the problem of finding the optimal deployment location and time for each vehicle, and for a given sequence of deployments, so that the global mission duration is minimal. The problem is specialized for ocean-going vehicles operating under time-varying currents. The solution approach involves solving a sequence of optimal stopping problems that are transformed into a set variational inequalities through the application of the dynamic programming principle (DPP). The optimal trajectory for the carrier and the optimal deployment location and time for each vehicle to be deployed are obtained in feedback-form from the numerical solution of the variational inequalities. The solution is computed with our open source parallel implementation of the fast sweeping method. The approach is illustrated with two numerical examples.

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  • 10.
    Ahlberg, Sofie
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Reglerteknik.
    Axelsson, Agnes
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Tal, musik och hörsel, TMH.
    Yu, Pian
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Reglerteknik.
    Shaw Cortez, Wenceslao E.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Reglerteknik.
    Gao, Yuan
    Uppsala Univ, Dept Informat Technol, Uppsala, Sweden.;Shenzhen Inst Artificial Intelligence & Robot Soc, Ctr Intelligent Robots, Shenzhen, Peoples R China..
    Ghadirzadeh, Ali
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Castellano, Ginevra
    Uppsala Univ, Dept Informat Technol, Uppsala, Sweden..
    Kragic, Danica
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Skantze, Gabriel
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Tal, musik och hörsel, TMH.
    Dimarogonas, Dimos V.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Reglerteknik.
    Co-adaptive Human-Robot Cooperation: Summary and Challenges2022Ingår i: Unmanned Systems, ISSN 2301-3850, E-ISSN 2301-3869, Vol. 10, nr 02, s. 187-203Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The work presented here is a culmination of developments within the Swedish project COIN: Co-adaptive human-robot interactive systems, funded by the Swedish Foundation for Strategic Research (SSF), which addresses a unified framework for co-adaptive methodologies in human-robot co-existence. We investigate co-adaptation in the context of safe planning/control, trust, and multi-modal human-robot interactions, and present novel methods that allow humans and robots to adapt to one another and discuss directions for future work.

  • 11.
    Alberti, Marina
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP.
    Jensfelt, Patric
    KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP. KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS. KTH, Skolan för kemivetenskap (CHE).
    Folkesson, John
    KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS. KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP.
    Relational approaches for joint object classification andscene similarity measurement in indoor environments2014Ingår i: Proc. of 2014 AAAI Spring Symposium QualitativeRepresentations for Robots 2014, Palo Alto, California: The AAAI Press , 2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    The qualitative structure of objects and their spatial distribution,to a large extent, define an indoor human environmentscene. This paper presents an approach forindoor scene similarity measurement based on the spatialcharacteristics and arrangement of the objects inthe scene. For this purpose, two main sets of spatialfeatures are computed, from single objects and objectpairs. A Gaussian Mixture Model is applied both onthe single object features and the object pair features, tolearn object class models and relationships of the objectpairs, respectively. Given an unknown scene, the objectclasses are predicted using the probabilistic frameworkon the learned object class models. From the predictedobject classes, object pair features are extracted. A fi-nal scene similarity score is obtained using the learnedprobabilistic models of object pair relationships. Ourmethod is tested on a real world 3D database of deskscenes, using a leave-one-out cross-validation framework.To evaluate the effect of varying conditions on thescene similarity score, we apply our method on mockscenes, generated by removing objects of different categoriesin the test scenes.

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  • 12.
    Alexanderson, Simon
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    House, David
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Beskow, Jonas
    KTH, Skolan för datavetenskap och kommunikation (CSC), Tal, musik och hörsel, TMH.
    Automatic annotation of gestural units in spontaneous face-to-face interaction2016Ingår i: MA3HMI 2016 - Proceedings of the Workshop on Multimodal Analyses Enabling Artificial Agents in Human-Machine Interaction, 2016, s. 15-19Konferensbidrag (Refereegranskat)
    Abstract [en]

    Speech and gesture co-occur in spontaneous dialogue in a highly complex fashion. There is a large variability in the motion that people exhibit during a dialogue, and different kinds of motion occur during different states of the interaction. A wide range of multimodal interface applications, for example in the fields of virtual agents or social robots, can be envisioned where it is important to be able to automatically identify gestures that carry information and discriminate them from other types of motion. While it is easy for a human to distinguish and segment manual gestures from a flow of multimodal information, the same task is not trivial to perform for a machine. In this paper we present a method to automatically segment and label gestural units from a stream of 3D motion capture data. The gestural flow is modeled with a 2-level Hierarchical Hidden Markov Model (HHMM) where the sub-states correspond to gesture phases. The model is trained based on labels of complete gesture units and self-adaptive manipulators. The model is tested and validated on two datasets differing in genre and in method of capturing motion, and outperforms a state-of-the-art SVM classifier on a publicly available dataset.

  • 13.
    Alhusin Alkhdur, Abdullah
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Hållbara produktionssystem.
    Wang, Lihui
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Hållbara produktionssystem.
    Intelligent human-robot assembly enabled by brain EEG2021Ingår i: Advanced Human-Robot Collaboration in Manufacturing, Springer Nature , 2021, s. 351-371Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    This chapter reports a framework that can facilitate the interactions between a human's EEG (electroencephalography) signals and an industrial robot. This can be achieved by using an EEG headset that captures the brain signals of the human and send it via Bluetooth to a local workstation for signal processing, feature extraction and classification. The system developed provides the ability for a shop-floor operator to control the robot using own brain signals. The system can cooperate with other channels of communications (gesture, voice, etc.) to strengthen the collaboration between the human and the robot during shared assembly operations. Such a collaboration aims to fuse the high accuracy of the robot with the high versatility of the human. Therefore, the aim is to exploit the strength of both sides and enhance the quality and adaptability of human-robot collaborative assembly operations. This approach is applicable to other types of robots as well, for example ones used for assisting people with severe disability.

  • 14.
    Alhusin Alkhdur Mohammed, Abdullah
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Wang, Lihui
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Hållbara produktionssystem.
    Advanced human-robot collaborative assembly using electroencephalogram signals of human brains2020Ingår i: Procedia CIRP, Elsevier B.V. , 2020, s. 1200-1205Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper introduces an intelligent system that can manipulate an industrial robot using the electroencephalogram signals of human brains to perform collaborative assembly tasks. The system is initiated by capturing the brain signals using a wearable headset, and the signals are then filtered to remove any possible artifact. Consequently, the process continues by identifying the brain signals patterns using a classifier based on pre-recorded samples. The classifier's output determines the proper matching of the robot command that is intended by the human. To validate the results, an industrial collaborative assembly scenario of a car manifold is examined as a case study. 

  • 15.
    Al-Janabi, Mustafa
    KTH, Skolan för elektroteknik och datavetenskap (EECS).
    Trajectory Optimization of Smart City Scenarios Using Learning Model Predictive Control2023Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Smarta städer använder modern teknik för att förbättra transporteffektiviteten och säkerheten. Med införandet av 5G och ett allt större nätverk av uppkopplade sensorsystem för infrastruktur blir realtidsmedvetenhet om vägförhållandena en verklighet. Denna utveckling medför nya utmaningar. Kommunikationen mellan autonoma fordon och uppkopplade sensorsystem ger upphov till stora mängder data som måste hanteras. Dessutom kommer fordon med olika autocnominivåer (från 0 till 5) att behöva dela gatorna tillsammans med människostyrda fordon samtidigt under en tid. I detta arbete tillämpar vi en datadriven reglermetod som heter Learning Model Predictive Control (LMPC) på tre olika scenarier i en smart stad med ökande komplexitet. LMPC utnyttjar data från en tidigare lyckad körning av ett visst scenario för att förbättra prestandan på efterföljande körningar samtidigt som säkerheten och rekursiv genomförbarhet garanteras. Vidare garanteras att prestandan från en körning till en annan inte minskar. För våra tre scenarier är målet att minimerar restiden och börjar med ett enda fordon i en tvåfilig korsning. Sedan lägger vi till ett hinder på högra filen och till sist lägger vi till mötande trafik. Vi finner att LMPC ger oss förbättrad trafikeffektivitet med kortare restid. Vi finner dock att LMPC må vara mindre lämplig för realtids scenarier. Således drar vi slutsatsen att denna metod är lämplig för optimering i simulatorer, offline, på data som kan genereras från autonoma fordon och sensorsystemet i infrastrukturen. Så småningom kan vår metod användas för att konstruera stora dataset av optimala trajektorier som är tillgängliga för uppkopplade fordon i framtidens smarta städer.

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  • 16.
    Allshire, Arthur
    et al.
    Univ Toronto, Vector Inst, Toronto, ON, Canada.;Nvidia, Santa Clara, CA 95051 USA..
    Mittal, Mayank
    Nvidia, Santa Clara, CA 95051 USA.;ETH, Zurich, Switzerland..
    Lodaya, Varun
    Univ Toronto, Vector Inst, Toronto, ON, Canada..
    Makoviychuk, Viktor
    Nvidia, Santa Clara, CA 95051 USA..
    Makoviichuk, Denys
    Snap, Santa Monica, CA USA..
    Widmaier, Felix
    MPI Tubingen, Tubingen, Germany..
    Wuthrich, Manuel
    MPI Tubingen, Tubingen, Germany..
    Bauer, Stefan
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system.
    Handa, Ankur
    Nvidia, Santa Clara, CA 95051 USA..
    Garg, Animesh
    Univ Toronto, Vector Inst, Toronto, ON, Canada.;Nvidia, Santa Clara, CA 95051 USA..
    Transferring Dexterous Manipulation from GPU Simulation to a Remote Real-World TriFinger2022Ingår i: 2022 IEEE/RS international conference on intelligent robots and systems (IROS), Institute of Electrical and Electronics Engineers (IEEE) , 2022, s. 11802-11809Konferensbidrag (Refereegranskat)
    Abstract [en]

    In-hand manipulation of objects is an important capability to enable robots to carry-out tasks which demand high levels of dexterity. This work presents a robot systems approach to learning dexterous manipulation tasks involving moving objects to arbitrary 6-DoF poses. We show empirical benefits, both in simulation and sim-to-real transfer, of using keypoint-based representations for object pose in policy observations and reward calculation to train a model-free reinforcement learning agent. By utilizing domain randomization strategies and large-scale training, we achieve a high success rate of 83% on a real TriFinger system, with a single policy able to perform grasping, ungrasping, and finger gaiting in order to achieve arbitrary poses within the workspace. We demonstrate that our policy can generalise to unseen objects, and success rates can be further improved through finetuning. With the aim of assisting further research in learning in-hand manipulation, we provide a detailed exposition of our system and make the codebase of our system available, along with checkpoints trained on billions of steps of experience, at https://s2r2-ig.github.io

  • 17.
    Almeida, Diogo
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Dual-Arm Robotic Manipulation under Uncertainties and Task-Based Redundancy2019Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Robotic manipulators are mostly employed in industrial environments, where their tasks can be prescribed with little to no uncertainty. This is possible in scenarios where the deployment time of robot workcells is not prohibitive, such as in the automotive industry. In other contexts, however, the time cost of setting up a classical robotic automation workcell is often prohibitive. This is the case with cellphone manufacturing, for example, which is currently mostly executed by human workers. Robotic automation is nevertheless desirable in these human-centric environments, as a robot can automate the most tedious parts of an assembly. To deploy robots in these environments, however, requires an ability to deal with uncertainties and to robustly execute any given task. In this thesis, we discuss two topics related to autonomous robotic manipulation. First, we address parametric uncertainties in manipulation tasks, such as the location of contacts during the execution of an assembly. We propose and experimentally evaluate two methods that rely on force and torque measurements to produce estimates of task related uncertainties: a method for dexterous manipulation under uncertainties which relies on a compliant rotational degree of freedom at the robot's gripper grasp point and exploits contact  with an external surface, and a cooperative manipulation system which is able to identify the kinematics of a two degrees of freedom mechanism. Then, we consider redundancies in dual-arm robotic manipulation. Dual-armed robots offer a large degree of redundancy which can be exploited to ensure a more robust task execution. When executing an assembly task, for instance, robots can freely change the location of the assembly in their workspace without affecting the task execution. We discuss methods that explore these types of redundancies in relative motion tasks in the form of asymmetries in their execution. Finally, we approach the converse problem by presenting a system which is able to balance measured forces and torques at its end-effectors by leveraging relative motion between them, while grasping a rigid tray. This is achieved through discrete sliding of the grasp points, which constitutes a novel application of bimanual dexterous manipulation.

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  • 18.
    Almeida, Diogo
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Robotik, perception och lärande, RPL.
    Ambrus, Rares
    KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP.
    Caccamo, Sergio
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Chen, Xi
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Cruciani, Silvia
    Pinto Basto De Carvalho, Joao F
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Haustein, Joshua
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Marzinotto, Alejandro
    KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP.
    Vina, Francisco
    KTH.
    Karayiannidis, Yiannis
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Ögren, Petter
    KTH, Skolan för teknikvetenskap (SCI), Matematik (Inst.), Optimeringslära och systemteori.
    Jensfelt, Patric
    KTH, Skolan för datavetenskap och kommunikation (CSC), Robotik, perception och lärande, RPL.
    Kragic, Danica
    KTH, Skolan för datavetenskap och kommunikation (CSC), Robotik, perception och lärande, RPL.
    Team KTH’s Picking Solution for the Amazon Picking Challenge 20162017Ingår i: Warehouse Picking Automation Workshop 2017: Solutions, Experience, Learnings and Outlook of the Amazon Robotics Challenge, 2017Konferensbidrag (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    In this work we summarize the solution developed by Team KTH for the Amazon Picking Challenge 2016 in Leipzig, Germany. The competition simulated a warehouse automation scenario and it was divided in two tasks: a picking task where a robot picks items from a shelf and places them in a tote and a stowing task which is the inverse task where the robot picks items from a tote and places them in a shelf. We describe our approach to the problem starting from a high level overview of our system and later delving into details of our perception pipeline and our strategy for manipulation and grasping. The solution was implemented using a Baxter robot equipped with additional sensors.

  • 19.
    Almeida, Diogo
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Ambrus, Rares
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Caccamo, Sergio
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Chen, Xi
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Cruciani, Silvia
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Pinto Basto de Carvalho, Joao Frederico
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Haustein, Joshua
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Marzinotto, Alejandro
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Viña, Francisco
    Karayiannidis, Yiannis
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Ögren, Petter
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Jensfelt, Patric
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Kragic, Danica
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Team KTH’s Picking Solution for the Amazon Picking Challenge 20162020Ingår i: Advances on Robotic Item Picking: Applications in Warehousing and E-Commerce Fulfillment, Springer Nature , 2020, s. 53-62Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    In this chapter we summarize the solution developed by team KTH for the Amazon Picking Challenge 2016 in Leipzig, Germany. The competition, which simulated a warehouse automation scenario, was divided into two parts: a picking task, where the robot picks items from a shelf and places them into a tote, and a stowing task, where the robot picks items from a tote and places them in a shelf. We describe our approach to the problem starting with a high-level overview of the system, delving later into the details of our perception pipeline and strategy for manipulation and grasping. The hardware platform used in our solution consists of a Baxter robot equipped with multiple vision sensors.

  • 20.
    Almeida, Diogo
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Ataer-Cansizoglu, Esra
    Wayfair, Boston, MA 02116, USA.
    Corcodel, Radu
    Mitsubishi Electric Research Labs (MERL), Cambridge, MA 02139, USA.
    Detection, Tracking and 3D Modeling of Objects with Sparse RGB-D SLAM and Interactive Perception2019Ingår i: IEEE-RAS International Conference on Humanoid Robots (Humanoids), 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    We present an interactive perception system that enables an autonomous agent to deliberately interact with its environment and produce 3D object models. Our system verifies object hypotheses through interaction and simultaneously maintains 3D SLAM maps for each rigidly moving object hypothesis in the scene. We rely on depth-based segmentation and a multigroup registration scheme to classify features into various object maps. Our main contribution lies in the employment of a novel segment classification scheme that allows the system to handle incorrect object hypotheses, common in cluttered environments due to touching objects or occlusion. We start with a single map and initiate further object maps based on the outcome of depth segment classification. For each existing map, we select a segment to interact with and execute a manipulation primitive with the goal of disturbing it. If the resulting set of depth segments has at least one segment that did not follow the dominant motion pattern of its respective map, we split the map, thus yielding updated object hypotheses. We show qualitative results with a Fetch manipulator and objects of various shapes, which showcase the viability of the method for identifying and modelling multiple objects through repeated interactions.

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  • 21.
    Almeida, Diogo
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Robotik, perception och lärande, RPL. KTH.
    Karayiannidis, Yiannis
    KTH, Skolan för datavetenskap och kommunikation (CSC), Robotik, perception och lärande, RPL. Dept. of Electrical Eng., Chalmers University of Technology.
    A Framework for Bimanual Folding Assembly Under Uncertainties2017Ingår i: Workshop – Towards robust grasping and manipulation skills for humanoids, 2017Konferensbidrag (Övrigt vetenskapligt)
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  • 22.
    Almeida, Diogo
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Karayiannidis, Yiannis
    A Lyapunov-Based Approach to Exploit Asymmetries in Robotic Dual-Arm Task Resolution2019Ingår i: 58th IEEE Conference on Decision and Control (CDC), 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    Dual-arm manipulation tasks can be prescribed to a robotic system in terms of desired absolute and relative motion of the robot’s end-effectors. These can represent, e.g., jointly carrying a rigid object or performing an assembly task. When both types of motion are to be executed concurrently, the symmetric distribution of the relative motion between arms prevents task conflicts. Conversely, an asymmetric solution to the relative motion task will result in conflicts with the absolute task. In this work, we address the problem of designing a control law for the absolute motion task together with updating the distribution of the relative task among arms. Through a set of numerical results, we contrast our approach with the classical symmetric distribution of the relative motion task to illustrate the advantages of our method.

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  • 23.
    Almeida, Diogo
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Karayiannidis, Yiannis
    Chalmers Univ Technol, Dept Elect Engn, S-41296 Gothenburg, Sweden..
    Asymmetric Dual-Arm Task Execution Using an Extended Relative Jacobian2022Ingår i: Robotics Research: 19th International Symposium  ISRR / [ed] Asfour, T Yoshida, E Park, J Christensen, H Khatib, O, Springer Nature , 2022, Vol. 20, s. 18-34Konferensbidrag (Refereegranskat)
    Abstract [en]

    Coordinated dual-arm manipulation tasks can be broadly characterized as possessing absolute and relative motion components. Relative motion tasks, in particular, are inherently redundant in the way they can be distributed between end-effectors. In this work, we analyse cooperative manipulation in terms of the asymmetric resolution of relative motion tasks. We discuss how existing approaches enable the asymmetric execution of a relative motion task, and show how an asymmetric relative motion space can be defined. We leverage this result to propose an extended relative Jacobian to model the cooperative system, which allows a user to set a concrete degree of asymmetry in the task execution. This is achieved without the need for prescribing an absolute motion target. Instead, the absolute motion remains available as a functional redundancy to the system. We illustrate the properties of our proposed Jacobian through numerical simulations of a novel differential Inverse Kinematics algorithm.

  • 24.
    Almeida, Diogo
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Karayiannidis, Yiannis
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Asymmetric Dual-Arm Task Execution using an Extended Relative Jacobian2019Ingår i: The International Symposium on Robotics Research, 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    Coordinated dual-arm manipulation tasks can be broadly characterized as possessing absolute and relative motion components. Relative motion tasks, in particular, are inherently redundant in the way they can be distributed between end-effectors. In this work, we analyse cooperative manipulation in terms of the asymmetric resolution of relative motion tasks. We discuss how existing approaches enable the asymmetric execution of a relative motion task, and show how an asymmetric relative motion space can be defined. We leverage this result to propose an extended relative Jacobian to model the cooperative system, which allows a user to set a concrete degree of asymmetry in the task execution. This is achieved without the need for prescribing an absolute motion target. Instead, the absolute motion remains available as a functional redundancy to the system. We illustrate the properties of our proposed Jacobian through numerical simulations of a novel differential Inverse Kinematics algorithm.

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  • 25.
    Almeida, Diogo
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Karayiannidis, Yiannis
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL. Dept. of Electrical Eng., Chalmers University of Technology.
    Cooperative Manipulation and Identification of a 2-DOF Articulated Object by a Dual-Arm Robot2018Ingår i: 2018 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION (ICRA) / [ed] IEEE, 2018, s. 5445-5451Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this work, we address the dual-arm manipula-tion of a two degrees-of-freedom articulated object that consistsof two rigid links. This can include a linkage constrainedalong two motion directions, or two objects in contact, wherethe contact imposes motion constraints. We formulate theproblem as a cooperative task, which allows the employment ofcoordinated task space frameworks, thus enabling redundancyexploitation by adjusting how the task is shared by the robotarms. In addition, we propose a method that can estimate thejoint location and the direction of the degrees-of-freedom, basedon the contact forces and the motion constraints imposed bythe object. Experimental results demonstrate the performanceof the system in its ability to estimate the two degrees of freedomindependently or simultaneously.

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  • 26.
    Almeida, Diogo
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Robotik, perception och lärande, RPL. KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS. KTH.
    Karayiannidis, Yiannis
    Chalmers, Sweden.
    Dexterous manipulation by means of compliant grasps and external contacts2017Ingår i: 2017 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2017, IEEE, 2017, s. 1913-1920, artikel-id 8206010Konferensbidrag (Refereegranskat)
    Abstract [en]

    We propose a method that allows for dexterousmanipulation of an object by exploiting contact with an externalsurface. The technique requires a compliant grasp, enablingthe motion of the object in the robot hand while allowingfor significant contact forces to be present on the externalsurface. We show that under this type of grasp it is possibleto estimate and control the pose of the object with respect tothe surface, leveraging the trade-off between force control andmanipulative dexterity. The method is independent of the objectgeometry, relying only on the assumptions of type of grasp andthe existence of a contact with a known surface. Furthermore,by adapting the estimated grasp compliance, the method canhandle unmodelled effects. The approach is demonstrated andevaluated with experiments on object pose regulation andpivoting against a rigid surface, where a mechanical springprovides the required compliance.

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  • 27.
    Almeida, Diogo
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Karayiannidis, Yiannis
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL. Chalmers University of Technology.
    Folding Assembly by Means of Dual-Arm Robotic Manipulation2016Ingår i: 2016 IEEE International Conference on Robotics and Automation, IEEE conference proceedings, 2016, s. 3987-3993Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we consider folding assembly as an assembly primitive suitable for dual-arm robotic assembly, that can be integrated in a higher level assembly strategy. The system composed by two pieces in contact is modelled as an articulated object, connected by a prismatic-revolute joint. Different grasping scenarios were considered in order to model the system, and a simple controller based on feedback linearisation is proposed, using force torque measurements to compute the contact point kinematics. The folding assembly controller has been experimentally tested with two sample parts, in order to showcase folding assembly as a viable assembly primitive.

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  • 28.
    Almeida, Diogo
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Robotik, perception och lärande, RPL. KTH.
    Karayiannidis, Yiannis
    Robotic Manipulation for Bi-Manual Folding Assembly2015Ingår i: Late Breaking Posters, 2015Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    In this poster the problem of bimanual robotic assembly is considered. In particular we introduce folding assembly which is an assembly task that requires significant rotational motion in order to mate two assembly pieces. We model the connection between the two parts as an ideal virtual prismatic and revolute joint while non-ideal effects on the part movements can be considered as special cases of the ideal virtual joint. The connection between the gripper and the assembly part is also studied by considering the case of rigid and non-rigid grasp. As a proof-of-concept, a stabilizing controller for the assembly task is derived following a bimanual master-slave approach under the assumption of rigid grasps. The controller is validated through simulation while an example object has been designed and printed for experimental validation of our assembly technique.

  • 29.
    Almeida, Diogo
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Robotik, perception och lärande, RPL. KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS.
    Viña, Francisco E.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Robotik, perception och lärande, RPL. KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS.
    Karayiannidis, Yiannis
    Bimanual Folding Assembly: Switched Control and Contact Point Estimation2016Ingår i: IEEE-RAS 16th International Conference on Humanoid Robots (Humanoids), Cancun, 2016, Cancun: IEEE, 2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Robotic assembly in unstructured environments is a challenging task, due to the added uncertainties. These can be mitigated through the employment of assembly systems, which offer a modular approach to the assembly problem via the conjunction of primitives. In this paper, we use a dual-arm manipulator in order to execute a folding assembly primitive. When executing a folding primitive, two parts are brought into rigid contact and posteriorly translated and rotated. A switched controller is employed in order to ensure that the relative motion of the parts follows the desired model, while regulating the contact forces. The control is complemented with an estimator based on a Kalman filter, which tracks the contact point between parts based on force and torque measurements. Experimental results are provided, and the effectiveness of the control and contact point estimation is shown.

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  • 30.
    Almeida, João Tiago
    et al.
    KTH.
    Leite, Iolanda
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Yadollahi, Elmira
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Would you help me?: Linking robot's perspective-taking to human prosocial behavior2023Ingår i: HRI 2023: Proceedings of the 2023 ACM/IEEE International Conference on Human-Robot Interaction, Association for Computing Machinery (ACM) , 2023, s. 388-397Konferensbidrag (Refereegranskat)
    Abstract [en]

    Despite the growing literature on human attitudes toward robots, particularly prosocial behavior, little is known about how robots' perspective-taking, the capacity to perceive and understand the world from other viewpoints, could infuence such attitudes and perceptions of the robot. To make robots and AI more autonomous and self-aware, more researchers have focused on developing cognitive skills such as perspective-taking and theory of mind in robots and AI. The present study investigated whether a robot's perspectivetaking choices could infuence the occurrence and extent of exhibiting prosocial behavior toward the robot.We designed an interaction consisting of a perspective-taking task, where we manipulated how the robot instructs the human to fnd objects by changing its frame of reference and measured the human's exhibition of prosocial behavior toward the robot. In a between-subject study (N=70), we compared the robot's egocentric and addressee-centric instructions against a control condition, where the robot's instructions were object-centric. Participants' prosocial behavior toward the robot was measured using a voluntary data collection session. Our results imply that the occurrence and extent of prosocial behavior toward the robot were signifcantly infuenced by the robot's visuospatial perspective-taking behavior. Furthermore, we observed, through questionnaire responses, that the robot's choice of perspectivetaking could potentially infuence the humans' perspective choices, were they to reciprocate the instructions to the robot.

  • 31.
    Alomari, Muhannad
    et al.
    Univ Leeds, Leeds, W Yorkshire, England..
    Duckworth, Paul
    Univ Leeds, Leeds, W Yorkshire, England..
    Bore, Nils
    KTH, Skolan för datavetenskap och kommunikation (CSC), Robotik, perception och lärande, RPL.
    Hawasly, Majd
    Univ Leeds, Leeds, W Yorkshire, England..
    Hogg, David C.
    Univ Leeds, Leeds, W Yorkshire, England..
    Cohn, Anthony G.
    Univ Leeds, Leeds, W Yorkshire, England..
    Grounding of human environments and activities for autonomous robots2017Ingår i: Proceedings Of The Twenty-Sixth International Joint Conference On Artificial Intelligence, International Joint Conferences on Artificial Intelligence , 2017, s. 1395-1402Konferensbidrag (Refereegranskat)
    Abstract [en]

    With the recent proliferation of human-oriented robotic applications in domestic and industrial scenarios, it is vital for robots to continually learn about their environments and about the humans they share their environments with. In this paper, we present a novel, online, incremental framework for unsupervised symbol grounding in real-world, human environments for autonomous robots. We demonstrate the flexibility of the framework by learning about colours, people names, usable objects and simple human activities, integrating stateofthe-art object segmentation, pose estimation, activity analysis along with a number of sensory input encodings into a continual learning framework. Natural language is grounded to the learned concepts, enabling the robot to communicate in a human-understandable way. We show, using a challenging real-world dataset of human activities as perceived by a mobile robot, that our framework is able to extract useful concepts, ground natural language descriptions to them, and, as a proof-ofconcept, generate simple sentences from templates to describe people and the activities they are engaged in.

  • 32. Althoff, Matthias
    et al.
    Maierhofer, Sebastian
    Pek, Christian
    Provably-Correct and Comfortable Adaptive Cruise Control2020Ingår i: IEEE Transactions on Intelligent Vehicles, ISSN 23798858, s. 1-1Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Adaptive cruise control is one of the most common comfort features of road vehicles. Despite its large market penetration, current systems are not safe in all driving conditions and require supervision by human drivers. While several previous works have proposed solutions for safe adaptive cruise control, none of these works considers comfort, especially in the event of cut-ins. We provide a novel solution that simultaneously meets our specifications and provides comfort in all driving conditions including cut-ins. This is achieved by an exchangeable nominal controller ensuring comfort combined with a provably correct fail-safe controller that gradually engages an emergency maneuver—this ensures comfort, since most threats are already cleared before emergency braking is fully activated. As a conse- quence, one can easily exchange the nominal controller without having to re-certify the overall system safety. We also provide the first user study for a provably correct adaptive cruise controller. It shows that even though our approach never causes an accident, passengers rate the performance as good as a state-of-the-art solution that does not ensure safety.

  • 33.
    Ambrus, Rares
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP. KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS.
    Bore, Nils
    KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP. KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS.
    Folkesson, John
    KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP. KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS.
    Jensfelt, Patric
    KTH, Skolan för datavetenskap och kommunikation (CSC), Datorseende och robotik, CVAP. KTH, Skolan för datavetenskap och kommunikation (CSC), Centra, Centrum för Autonoma System, CAS.
    Meta-rooms: Building and Maintaining Long Term Spatial Models in a Dynamic World2014Ingår i: 2014 IEEE/RSJ International Conference on Intelligent Robots and Systems, (IROS 2014), IEEE conference proceedings, 2014, s. 1854-1861Konferensbidrag (Refereegranskat)
    Abstract [en]

    We present a novel method for re-creating the static structure of cluttered office environments -which we define as the " meta-room" -from multiple observations collected by an autonomous robot equipped with an RGB-D depth camera over extended periods of time. Our method works directly with point clusters by identifying what has changed from one observation to the next, removing the dynamic elements and at the same time adding previously occluded objects to reconstruct the underlying static structure as accurately as possible. The process of constructing the meta-rooms is iterative and it is designed to incorporate new data as it becomes available, as well as to be robust to environment changes. The latest estimate of the meta-room is used to differentiate and extract clusters of dynamic objects from observations. In addition, we present a method for re-identifying the extracted dynamic objects across observations thus mapping their spatial behaviour over extended periods of time.

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  • 34.
    Andersson, Klas
    a Dept. of Mech. and Astronautical Eng., Naval Postgraduate School, Monterey, CA, United States.
    Extending Endurance for Small UAVs by Predicting and Searching for Thermal Updrafts2009Konferensbidrag (Refereegranskat)
  • 35.
    Andersson, Klas
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Robotik, perception och lärande, RPL.
    Improving Fixed Wing UAV Endurance, by Cooperative Autonomous Soaring2021Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Utvecklingen och användandet av mindre UAVer är ett område som ständigt växer. Hand i hand med denna utveckling kommer även behov och kravpå ökad prestanda som t.ex. längre räckvidd och uthållighet för denna typ avUAVer. Denna avhandling redogör för utvecklingen av ett system där samarbetande UAVer utför termik-flygning autonomt. Syftet med systemet är att dra nytta av energi i form av uppvindar eller termik som finns tillgänglig atmosfären på samma sätt som många fågelarter och bemannade segelflygplan gör för att på så sätt öka uthålligheten. Genom att utnyttja denna gratis-energi kan avsevärda förbättringar i maximal uthållighet och räckvidd uppnås.Arbetet omfattade teoretisk analys, simuleringar och slutligen flygprovning av det framtagna och utvecklade systemet. Systemet utvecklades initialt till ett koncept bestående av en flygfarkost som autonomt genom för determik-flygning. Därefter utvecklades systemet till att omfatta två samarbetande flygplan syftande till att förbättra prestandan genom att öka förmågan att hitta eller lokalisera uppvindar i form av termik.Den teoretiska analysen visade att algoritmens termikcentrerings kontrollär stabil. Flygtesterna påvisade vidare att det utvecklade systemet för autonom termikflygning fungerade som förväntat från simuleringarna. Dessutom visade flygproven att betydande prestandaförbättringar i uthållighet kan uppnås, under tämligen varierande väderförhållanden, genom att använda dennateknik.Försöken med samarbetande termikflygande UAVer, visade sig också fungera som avsett. UAVerna hittade, samarbetade och steg tillsammans i termikblåsor. Flygningen med samarbetande autonomt termikflygande UAVerär förmodligen det första och enda lyckade försök i sitt slag som genomförts hittills. Fler försök skulle dock vara värdefullt för att kunna dra ytterligare slutsatser om eventuella för- och nackdelar med detta koncept. Försöken uppmärksammade även potentiella problem och begränsningar,och ett antal tänkbara förbättringar identifierades. Som en del av arbetet gjordes försök i syfte att verifiera möjligheten att implementera systemet på ett verkligt operativt scenario. Detta genomför dessom ett konceptförsök där de termiksökande UAVerna fick agera relästation för kommunikation/datatrafik. Kommunikationen som vidarebefordrades varmellan andra UAV-system som befann sig utanför räckvidd, som sände bilddata tillbaka till markstationen. Försöken föll väl ut och konceptet föreföll mycket lämpligt för denna typ av uppdrag. Kommunikations-reläsystemet vidareutvecklades till ett hybridsystem där den ideala positionen för att agera relästation söktes upp autonomt, varefter fokus istället skiftades till att sökatermik i närområdet av denna optimala reläposition. Hybridsystemet provades i simuleringar, och delvis även i flygförsök.

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  • 36.
    Andersson, Klas
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC). the Dept. of Mech. & Aeronautical Eng. Naval Postgraduate School, Monterey, CA 93940 USA.
    Jones, Kevin
    Dobrokhodov, Vladimir
    Kaminer, Isaac
    Thermal highs and pitfall lows - notes on the journey to the first cooperative autonomous soaring flight2012Ingår i: 2012 IEEE 51st IEEE Conference on Decision and Control (CDC), Institute of Electrical and Electronics Engineers (IEEE), 2012, s. 3392-3397Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper discusses the development and flight testing of an algorithm for cooperative soaring by multiple autonomous gliders. Flight test results confirmed that the algorithm functioned as expected and that the gliders worked cooperatively to find and utilize the same updrafts during the test. However, the flight also indicated that the effectiveness of the strategy depends largely on the existing thermal conditions in combination with how restrictively the limits of separation be tween the cooperating gliders are set. To the best of the authors' knowledge this was the world's first cooperative autonomous thermal soaring flight.

  • 37.
    Andersson, Klas
    et al.
    Naval Postgraduate School, Monterey, California 93943.
    Kaminer, Isaac
    Naval Postgraduate School, Monterey, California 93943.
    Dobrokhodov, Vladimir
    Naval Postgraduate School, Monterey, California 93943.
    Cichella, Venanzio
    Universita’ di Bologna, 40126 Bologna, Italy.
    Thermal Centering Control for Autonomous Soaring; Stability Analysis and Flight Test Results2012Ingår i: Journal of Guidance Control and Dynamics, ISSN 0731-5090, E-ISSN 1533-3884, Vol. 35, nr 3, s. 963-975Artikel i tidskrift (Refereegranskat)
  • 38.
    Andersson, Klas
    et al.
    Naval Postgraduate Shool.
    Kaminer, Issac
    Naval Postgraduate Shool.
    Jones, Kevin
    Naval Postgraduate Shool.
    Dobrokhodov, Vladimir
    Naval Postgraduate Shool.
    Lee, Deok-Jin
    Naval Postgraduate Shool.
    Cooperating UAVs Using Thermal Lift to Extend Endurance2009Konferensbidrag (Refereegranskat)
  • 39. Andersson, O.
    et al.
    Doherty, P.
    Lager, M.
    Lindh, J. -O
    Persson, Linnea
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Reglerteknik.
    Topp, E. A.
    Tordenlid, J.
    Wahlberg, Bo
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Reglerteknik.
    WARA-PS: a research arena for public safety demonstrations and autonomous collaborative rescue robotics experimentation2021Ingår i: Autonomous Intelligent Systems, ISSN 2730-616X, Vol. 1, nr 1, artikel-id 9Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A research arena (WARA-PS) for sensing, data fusion, user interaction, planning and control of collaborative autonomous aerial and surface vehicles in public safety applications is presented. The objective is to demonstrate scientific discoveries and to generate new directions for future research on autonomous systems for societal challenges. The enabler is a computational infrastructure with a core system architecture for industrial and academic collaboration. This includes a control and command system together with a framework for planning and executing tasks for unmanned surface vehicles and aerial vehicles. The motivating application for the demonstration is marine search and rescue operations. A state-of-art delegation framework for the mission planning together with three specific applications is also presented. The first one concerns model predictive control for cooperative rendezvous of autonomous unmanned aerial and surface vehicles. The second project is about learning to make safe real-time decisions under uncertainty for autonomous vehicles, and the third one is on robust terrain-aided navigation through sensor fusion and virtual reality tele-operation to support a GPS-free positioning system in marine environments. The research results have been experimentally evaluated and demonstrated to industry and public sector audiences at a marine test facility. It would be most difficult to do experiments on this large scale without the WARA-PS research arena. Furthermore, these demonstrator activities have resulted in effective research dissemination with high public visibility, business impact and new research collaborations between academia and industry. 

  • 40.
    Andreanidis, Christos
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion, Mekatronik och inbyggda styrsystem.
    Bergsten, Johanna
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion, Mekatronik och inbyggda styrsystem.
    Brümmer, Marcel
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion, Mekatronik och inbyggda styrsystem.
    Fröberg, Joel
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion, Mekatronik och inbyggda styrsystem.
    Lindestam, Algot
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion, Mekatronik och inbyggda styrsystem.
    Persson, Annie
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion, Mekatronik och inbyggda styrsystem.
    Pirmohamed, Fahim
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion, Mekatronik och inbyggda styrsystem.
    Sandahl, Maria
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion, Mekatronik och inbyggda styrsystem.
    Thorapalli Muralidharan, Seshagopalan
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion, Mekatronik och inbyggda styrsystem.
    Andrikopoulos, Georgios
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion, Mekatronik och inbyggda styrsystem.
    On the Design and Development of a Tabletop Robot for Interaction with Children2023Ingår i: 2023 IEEE/ASME International Conference on Advanced Intelligent Mechatronics, AIM 2023, Institute of Electrical and Electronics Engineers (IEEE) , 2023, s. 1232-1237Konferensbidrag (Refereegranskat)
    Abstract [en]

    This article presents a novel emotionally expressive robot platform targeting social engagement with children. This platform was implemented in accordance with UNICEF's policy guidance on artificial intelligence (AI) for children, focusing on factors such as safety, transparency, reliability and explainability. The robot prototype is presented from a design and development perspective, outlining all utilized electromechanical components that enable its 11 degrees-of-freedom and sensing functions. Preliminary evaluation results are provided in terms of dependability and expressiveness of basic emotions, thus demonstrating the robot's potential to facilitate trustworthy and secure interactions with children.

  • 41.
    Andreasson, Martin
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik. KTH, Skolan för elektro- och systemteknik (EES), Centra, ACCESS Linnaeus Centre.
    Dimarogonas, Dimos V.
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik. KTH, Skolan för elektro- och systemteknik (EES), Centra, ACCESS Linnaeus Centre.
    Johansson, Karl H.
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik. KTH, Skolan för elektro- och systemteknik (EES), Centra, ACCESS Linnaeus Centre.
    Undamped Nonlinear Consensus Using Integral Lyapunov Functions2012Ingår i: 2012 American Control Conference (ACC), IEEE Computer Society, 2012, s. 6644-6649Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper analyzes a class of nonlinear consensus algorithms where the input of an agent can be decoupled into a product of a gain function of the agents own state, and a sum of interaction functions of the relative states of its neighbors. We prove the stability of the protocol for both single and double integrator dynamics using novel Lyapunov functions, and provide explicit formulas for the consensus points. The results are demonstrated through simulations of a realistic example within the framework of our proposed consensus algorithm.

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  • 42.
    Andreasson, Martin
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik. KTH, Skolan för elektro- och systemteknik (EES), Centra, ACCESS Linnaeus Centre.
    Dimarogonas, Dimos V.
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik. KTH, Skolan för elektro- och systemteknik (EES), Centra, ACCESS Linnaeus Centre.
    Sandberg, Henrik
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik. KTH, Skolan för elektro- och systemteknik (EES), Centra, ACCESS Linnaeus Centre.
    Johansson, Karl H.
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik. KTH, Skolan för elektro- och systemteknik (EES), Centra, ACCESS Linnaeus Centre.
    Distributed PI-Control with Applications to Power Systems Frequency Control2014Ingår i: American Control Conference (ACC), 2014, IEEE conference proceedings, 2014, s. 3183-3188Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper considers a distributed PI-controller for networked dynamical systems. Sufficient conditions for when the controller is able to stabilize a general linear system and eliminate static control errors are presented. The proposed controller is applied to frequency control of power transmission systems. Sufficient stability criteria are derived, and it is shown that the controller parameters can always be chosen so that the frequencies in the closed loop converge to nominal operational frequency. We show that the load sharing property of the generators is maintained, i.e., the input power of the generators is proportional to a controller parameter. The controller is evaluated by simulation on the IEEE 30 bus test network, where its effectiveness is demonstrated.

  • 43. Andrikopoulos, G.
    et al.
    Nikolakopoulos, G.
    Manesis, S.
    An experimental study on thermodynamic properties of Pneumatic Artificial Muscles2012Ingår i: 2012 20th Mediterranean Conference on Control &amp$\mathsemicolon$ Automation (MED), IEEE , 2012Konferensbidrag (Refereegranskat)
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  • 44. Andrikopoulos, George
    Development and Control of a Robotic Climber with Pneumatic Muscle Actuators2010Konferensbidrag (Refereegranskat)
  • 45. Andrikopoulos, George
    et al.
    Arvanitakis, J.
    Manesis, S.
    Nikolakopoulos, G.
    A switched system modeling approach for a Pneumatic Muscle Actuator2012Ingår i: 2012 IEEE International Conference on Industrial Technology, IEEE , 2012Konferensbidrag (Refereegranskat)
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  • 46. Andrikopoulos, George
    et al.
    Arvanitakis, John
    Nikolakopoulos, George
    Manesis, Stamatis
    Dynamic analysis and cascade movement simulation of a pneumatic muscle actuator2011Ingår i: Proceedings of the IASTED International Conference on Modelling, Simulation and Identification, 2011, s. 407-414Konferensbidrag (Refereegranskat)
    Abstract [en]

    The aim of this article is to present a dynamic analysis and a cascade movement simulation of a Pneumatic Muscle Actuator (PMA). PMAs are highly non–linear pneumatic actuators where their elongation are proportional to the interval pressure. Their non–linear characteristics and the property of the hysteresis are posing several difficulties in simulating these pneumatic actuators and to obtain a comprehension of the PMA’s physical movement. In this article a novel detailed modeling, based on hardware in the loop simulationstudies, capable to describe the dynamic characteristic of the PMA and a detailed simulation environment for studying the cascade movement of PMAs will be presented.

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  • 47. Andrikopoulos, George
    et al.
    Nikolakopoulos, G.
    Manesis, S.
    Non-linear control of Pneumatic Artificial Muscles2013Ingår i: 21st Mediterranean Conference on Control and Automation, IEEE , 2013Konferensbidrag (Refereegranskat)
  • 48. Andrikopoulos, George
    et al.
    Nikolakopoulos, George
    Design, development and control of a human-inspired two-arm robot via Pneumatic Artificial Muscles2017Ingår i: 2017 25th Mediterranean Conference on Control and Automation, MED 2017, 2017, s. 241-246Konferensbidrag (Refereegranskat)
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  • 49. Andrikopoulos, George
    et al.
    Nikolakopoulos, George
    On the design, development and motion control of a HUmanoid Robotic Leg via pneumatic artificial muscles2016Ingår i: 2016 IEEE International Conference on Robotics and Biomimetics (ROBIO), IEEE , 2016Konferensbidrag (Refereegranskat)
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  • 50. Andrikopoulos, George
    et al.
    Nikolakopoulos, George
    Kominiak, Dariusz
    Unander-Scharin, Asa
    Towards the development of a novel upper-body pneumatic humanoid: Design and implementation2016Ingår i: 2016 European Control Conference (ECC), IEEE , 2016Konferensbidrag (Refereegranskat)
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