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1.	Blanch, Krister, 1991 (author) Beyond-application datasets and automated fair benchmarking 2023 Licentiate thesis (other academic/artistic)abstract Beyond-application perception datasets are generalised datasets that emphasise the fundamental components of good machine perception data. When analysing the history of perception datatsets, notable trends suggest that design of the dataset typically aligns with an application goal. Instead of focusing on a specific application, beyond-application datasets instead look at capturing high-quality, high-volume data from a highly kinematic environment, for the purpose of aiding algorithm development and testing in general. Algorithm benchmarking is a cornerstone of autonomous systems development, and allows developers to demonstrate their results in a comparative manner. However, most benchmarking systems allow developers to use their own hardware or select favourable data. There is also little focus on run time performance and consistency, with benchmarking systems instead showcasing algorithm accuracy. By combining both beyond-application dataset generation and methods for fair benchmarking, there is also the dilemma of how to provide the dataset to developers for this benchmarking, as the result of a high-volume, high-quality dataset generation is a significant increase in dataset size when compared to traditional perception datasets. This thesis presents the first results of attempting the creation of such a dataset. The dataset was built using a maritime platform, selected due to the highly dynamic environment presented on water. The design and initial testing of this platform is detailed, as well as as methods of sensor validation. Continuing, the thesis then presents a method of fair benchmarking, by utilising remote containerisation in a way that allows developers to present their software to the dataset, instead of having to first locally store a copy. To test this dataset and automatic online benchmarking, a number of reference algorithms were required for initial results. Three algorithms were built, using the data from three different sensors captured on the maritime platform. Each algorithm calculates vessel odometry, and the automatic benchmarking system was utilised to show the accuracy and run-time performance of these algorithms. It was found that the containerised approach alleviated data management concerns, prevented inflated accuracy results, and demonstrated precisely how computationally intensive each algorithm was.
2.	Theorin, Alfred, et al. (author) An event-driven manufacturing information system architecture for Industry 4.0 2017 In: International Journal of Production Research. - : Taylor & Francis. - 0020-7543 .- 1366-588X. ; 55:5, s. 1297-1311 Research review (peer-reviewed)abstract Future manufacturing systems need to be more flexible, to embrace tougher and constantly changing market demands. They need to make better use of plant data, ideally utilising all data from the entire plant. Low-level data should be refined to real-time information for decision-making, to facilitate competitiveness through informed and timely decisions. The Line Information System Architecture (LISA), is presented in this paper. It is an event-driven architecture featuring loose coupling, a prototype-oriented information model and formalised transformation services. LISA is designed to enable flexible factory integration and data utilisation. The focus of LISA is on integration of devices and services on all levels, simplifying hardware changes and integration of new smart services as well as supporting continuous improvements on information visualisation and control. The architecture has been evaluated on both real industrial data and industrial demonstrators and it is also being installed at a large automotive company. This article is an extended and revised version of the paper presented at the 2015 IFAC Symposium on Information Control in Manufacturing (INCOM 2015). The paper has been restructured in regards to the order and title of the chapters, and additional information about the integration between devices and services aspects have been added. The introduction and the general structure of the paper now better highlight the contributions of the paper and the uniqueness of the framework.
3.	Westin, Jonathan, 1980, et al. (author) Digitising Sensitive Heritage Monuments In Antarctica 2024 In: The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XLVIII-2/W4-2024. 10th International Workshop 3D-ARCH "3D Virtual Reconstruction and Visualization of Complex Architectures, 21–23 February 2024, Siena, Italy / editor(s): S. Campana, F. Fassi, and F. Remondino. - : International Society for Photogrammetry and Remote Sensing. - 1682-1750. Conference paper (peer-reviewed)abstract During the Antarctica expedition CHAQ2020, several cultural heritage sites – remains from the Swedish South Polar Expedition (1901–1903) – were documented using a range of different techniques and technologies. These physical monuments and environments are for all intents and purposes unavailable for most researchers due to their remote location and are also threatened by the effects of climate change. Hence, the deployed documentation techniques and technologies were selected both as a consequence of the inherently difficult conditions in Antarctica, where their reliance, durability, and speed were key considerations, but also for their perceived ability to document the unique and fragile environment. The documentation was carried out with the double intention of both allowing for observations in situ through processes of analytical drawings and data capture, but also capturing the environment as broadly and deeply as possible, in essence making a copy of it open for studies of unknown unknowns, that could serve as a source material for research questions still undefined. Hence, with the documentation of the winter station on Snow Hill Island as a case study, and with a perspective on documentation as a method through which to process, preserve, and disseminate information, this article serves to critically detail, compare, and evaluate the digital techniques and technologies that the expedition deployed to capture architectural elements and spatial contexts, and the data that could be obtained through these.
4.	Augustian, Midhumol, et al. (author) EEG Analysis from Motor Imagery to Control a Forestry Crane 2018 In: Intelligent Human Systems Integration (IHSI 2018). - Cham : Springer. - 9783319738871 - 9783319738888 ; , s. 281-286 Conference paper (peer-reviewed)abstract Brain-computer interface (BCI) systems can provide people with ability to communicate and control real world systems using neural activities. Therefore, it makes sense to develop an assistive framework for command and control of a future robotic system which can assist the human robot collaboration. In this paper, we have employed electroencephalographic (EEG) signals recorded by electrodes placed over the scalp. The human-hand movement based motor imagery mentalization is used to collect brain signals over the motor cortex area. The collected µ-wave (8–13 Hz) EEG signals were analyzed with event-related desynchronization/synchronization (ERD/ERS) quantification to extract a threshold between hand grip and release movement and this information can be used to control forestry crane grasping and release functionality. The experiment was performed with four healthy persons to demonstrate the proof-of concept BCI system. From this study, it is demonstrated that the proposed method has potential to assist the manual operation of crane operators performing advanced task with heavy cognitive work load.
5.	Farooqui, Ashfaq, et al. (author) On Active Learning for Supervisor Synthesis 2024 In: IEEE Transactions on Automation Science and Engineering. - : Institute of Electrical and Electronics Engineers Inc.. - 1545-5955 .- 1558-3783. ; 21, s. 78- Journal article (peer-reviewed)abstract Supervisory control theory provides an approach to synthesize supervisors for cyber-physical systems using a model of the uncontrolled plant and its specifications. These supervisors can help guarantee the correctness of the closed-loop controlled system. However, access to plant models is a bottleneck for many industries, as manually developing these models is an error-prone and time-consuming process. An approach to obtaining a supervisor in the absence of plant models would help industrial adoption of supervisory control techniques. This paper presents, an algorithm to learn a controllable supervisor in the absence of plant models. It does so by actively interacting with a simulation of the plant by means of queries. If the obtained supervisor is blocking, existing synthesis techniques are employed to prune the blocking supervisor and obtain the controllable and non-blocking supervisor. Additionally, this paper presents an approach to interface the with a PLC to learn supervisors in a virtual commissioning setting. This approach is demonstrated by learning a supervisor of the well-known example simulated in Xcelgo Experior and controlled using a PLC. interacts with the PLC and learns a controllable supervisor for the simulated system. Note to Practitioners—Ensuring the correctness of automated systems is crucial. Supervisory control theory proposes techniques to help build control solutions that have certain correctness guarantees. These techniques rely on a model of the system. However, such models are typically unavailable and hard to create. Active learning is a promising technique to learn models by interacting with the system to be learned. This paper aims to integrate active learning and supervisory control such that the manual step of creating models is no longer needed, thus, allowing the use of supervisory control techniques in the absence of models. The proposed approach is implemented in a tool and demonstrated using a case study.
6.	Rosenstatter, Thomas, et al. (author) Modelling the Level of Trust in a Cooperative Automated Vehicle Control System 2018 In: IEEE transactions on intelligent transportation systems (Print). - Piscataway, NJ : IEEE Press. - 1524-9050 .- 1558-0016. ; 19:4, s. 1267-1247 Journal article (peer-reviewed)abstract Vehicle-to-vehicle communication is a key technology for achieving increased perception for automated vehicles, where the communication enables virtual sensing by means of sensors in other vehicles. In addition, this technology also allows detection and recognition of objects that are out-of-sight. This paper presents a trust system that allows a cooperative and automated vehicle to make more reliable and safe decisions. The system evaluates the current situation and generates a trust index indicating the level of trust in the environment, the ego vehicle, and the surrounding vehicles. This research goes beyond secure communication and concerns the verification of the received data on a system level. The results show that the proposed method is capable of correctly identifying various traffic situations and how the trust index is used while manoeuvring in a platoon merge scenario.
7.	Amundin, Mats, et al. (author) A proposal to use distributional models to analyse dolphin vocalisation 2017 In: Proceedings of the 1st International Workshop on Vocal Interactivity in-and-between Humans, Animals and Robots, VIHAR 2017. - 9782956202905 ; , s. 31-32 Conference paper (peer-reviewed)abstract This paper gives a brief introduction to the starting points of an experimental project to study dolphin communicative behaviour using distributional semantics, with methods implemented for the large scale study of human language.
8.	Johansson, Bengt (author) DC-DC Converters - Dynamic Model Design and Experimental Verification 2005 Doctoral thesis (other academic/artistic)abstract To obtain high performance control of a dc-dc converter, a good model of the converter is needed. The load usually affects the dynamics and one way to take this into consideration is to regard the load as a part of the converter. The load is often the most variable part of this system. If the load current and the output voltage are measured there are good possibilities to obtain a good model of the load on-line. Adaptive control can then be applied to improve the control. In peak current-mode control, the output voltage and the inductor current are measured and utilized for control. In the author's licentiate thesis, analytic models were derived for the case where the load current is also measured and utilized for control. The control-to-output transfer function, the output impedance, and the audio susceptibility were derived for the buck, boost, and buck-boost converters operated in continuous conduction mode in the case of resistive load. The use of load current can be seen as gain scheduling in the case where the load is a resistor. Gain scheduling can be considered a special case of adaptive control. The majority of the results in the licentiate thesis were validated by comparing the frequency responses predicted by the analytic models and switched large-signal simulation models. In this thesis, additional results are presented for the buck converter. Experimental results obtained by means of a network analyzer verify the derived control-to-output transfer function and the audio susceptibility but not the output impedance at low frequencies. In the experimental buck converter there are stray resistances in the inductor, transistor, and diode but these stray resistances were not considered in the licentiate thesis. A new transfer function for the output impedance is derived where these stray resistances are considered and it is in good agreement with the experimental result also at low frequencies. If the current to the output capacitor is measured in addition to the output voltage and the inductor current, the load current can be calculated as the difference between the inductor and capacitor currents in the case of the buck converter. Hence, the measurement of the load current can be replaced by measurement of the capacitor current. If this possibility is utilized and the capacitor current is measured by means of a current transformer, a low-frequency resonance is introduced in the frequency responses according to experimental results. The reason for this resonance is due to the high-pass-filter characteristics of the current transformer. A new analytic model is derived which predicts the resonance.
9.	Romero, Ines (author) Dynamic Power System Load -Estimation of Parameters from Operational Data 2005 Doctoral thesis (other academic/artistic)abstract The significance of load modeling for voltage stability studies has been emphasized by several disturbances, which have taken place in the past years. They have shown that the loads in combination with other dynamics are among the main contributors of prolonged low voltage conditions, voltage instability and collapse in the power system. As a result of these disturbances new investigations have come up to better understand the nature of the load. However, power system loads keep being very difficult to model; the load generally aggregates a large number of individual components of different nature, different load dynamics are excited depending on the time frame of actuation and the type of disturbance affecting the system, and the load is highly dependent on external factors such as weather conditions. This thesis investigates the load-voltage characteristic during two different time scales, long-term over several minutes, and short-term covering ms to several seconds, for different sized disturbances, and its impact on the calculation of transfer limits and security margins in voltage stability studies. The accurate determination of transfer limits will be an increasingly important task to maintain the operational security and economic dispatch of the power system. The location of the stability limits and the determination of transfer limits depend on the load-voltage characteristic since load relief due to the load-voltage dependency results in larger transfer limits. Moreover, the importance of using dynamic load models instead of static ones in stability studies is highlighted in this thesis. Due to the large amount of electrical heating loads in Sweden and its effect on voltage stability, a dynamic load model with exponential recovery, previously proposed by Hill and Karlsson, [Karlsson and Hill, 1994], has been the starting point for the investigations. Field measurements from continuous normal operation at the 20 kV-level from a substation in Sweden have provided a large amount of data covering all seasons during the time period July 2001-June 2002, and have resulted in extensive, unique and interesting recordings of active and reactive load characteristic and its dependency with small voltage variations. The data have revealed the variation of the load parameters and their dependency with weather and season of the year. The work has also contributed to a better approach for the normalization of traditional reactive load models. Furthermore the load-voltage characteristic during large disturbances has been investigated based on field measurements of phase-to-phase faults in a non-effectively earthed 50 kV system in Sweden. Three-phase currents and voltages have been used to estimate the active and reactive power. The recordings exhibited voltage dips up to 30% in the positive sequence voltage. The severity of the disturbances accentuates the nonlinear behavior of the load; the active and reactive power rapidly increase after fault clearing to levels even above the pre-disturbance value due to the re-acceleration of motors. The full recovery of the voltage is delayed due to the re-connection of tripped load. Moreover, it is shown that traditional load models do not accurately reflect the load behavior during these disturbances, for voltage dips around 12 % or larger due to the nonlinearities. An alternative load model, which represents the nonlinearities, has been tested. The superior behavior is demonstrated with the field measurements. Finally, some guidelines for industry to better account for the load in future stability studies have been included as a corollary of this thesis.
10.	Behdadi, Dorna, 1988, et al. (author) A Normative Approach to Artificial Moral Agency 2020 In: Minds and Machines. - : Springer Science and Business Media LLC. - 0924-6495 .- 1572-8641. ; 30:2, s. 195-218 Journal article (peer-reviewed)abstract This paper proposes a methodological redirection of the philosophical debate on artificial moral agency (AMA) in view of increasingly pressing practical needs due to technological development. This “normative approach” suggests abandoning theoretical discussions about what conditions may hold for moral agency and to what extent these may be met by artificial entities such as AI systems and robots. Instead, the debate should focus on how and to what extent such entities should be included in human practices normally assuming moral agency and responsibility of participants. The proposal is backed up by an analysis of the AMA debate, which is found to be overly caught in the opposition between so-called standard and functionalist conceptions of moral agency, conceptually confused and practically inert. Additionally, we outline some main themes of research in need of attention in light of the suggested normative approach to AMA.
11.	Schötz, Susanne, et al. (author) Phonetic Characteristics of Domestic Cat Vocalisations 2017 In: Proceedings of the 1st International Workshop on Vocal Interactivity in-and-between Humans, Animals and Robots, VIHAR 2017. - 9782956202905 ; , s. 5-6 Conference paper (peer-reviewed)abstract The cat (Felis catus, Linneaus 1758) has lived around or with humans for at least 10,000 years, and is now one of the most popular pets of the world with more than 600 millionindividuals. Domestic cats have developed a more extensive, variable and complex vocal repertoire than most other members of the Carnivora, which may be explained by their social organisation, their nocturnal activity and the long period of association between mother and young. Still, we know surprisingly little about the phonetic characteristics of these sounds, and about the interaction between cats and humans.Members of the research project Melody in human–cat communication (Meowsic) investigate the prosodic characteristics of cat vocalisations as well as the communication between human and cat. The first step includes a categorisation of cat vocalisations. In the next step it will be investigated how humans perceive the vocal signals of domestic cats. This paper presents an outline of the project which has only recently started.
12.	Theorin, Alfred, et al. (author) An Event-Driven Manufacturing Information System Architecture 2015 In: 15th IFAC Symposium onInformation Control Problems inManufacturing - INCOM 2015. - : Elsevier BV. ; 48:3, s. 547-554 Conference paper (peer-reviewed)abstract Future manufacturing systems need to be more flexible, to embrace tougher and constantly changing market demands. They also need to make better use of plant data, ideally utilizing all data from the entire plant. Low-level data should be refined to real-time information for decision making, to facilitate competitiveness through informed and timely decisions. The Line Information System Architecture, LISA, is designed to enable flexible factory integration and data utilization. In LISA, international standards and established off-the-shelf technologies have been combined with the main objective to be industrially applicable. LISA is an event-driven architecture with a prototype-oriented information model and formalized transformation services. It features loose coupling, flexibility, and ease of retrofitting legacy devices. The architecture has been evaluated on both real industrial data and industrial demonstrators and is also being installed at a large automotive company.
13.	Liu, Yang, et al. (author) A Study Towards Reliability- and Delay-Critical Wireless Communication for RoboCup Robotic Soccer Application 2007 In: 2007 International Conference on Wireless Communications, Networking and Mobile Computing. - : Institute of Electrical and Electronics Engineers (IEEE). - 1424413117 - 9781424413119 - 1424413125 - 1424413125 - 1424413117 ; , s. 633-636 Conference paper (peer-reviewed)abstract RoboCup is an international competition for a team of multiple fast-moving robots under a dynamic environment to autonomously play soccer game against another team. Due to the nature of the competition, the requirements and constraints for the wireless communication are extremely tight. The challenge is that wireless communication is involved in the control loop and therefore the reliability and propagation delay are vital factors which directly affect the team performance. Beside, various interferences with known and unknown frequency / transmission power usually exist at the competition site, which are hazardous environment to achieve reliable and low latency performance for wireless communication. This paper investigates the performance strengths and weaknesses of wireless communication means e.g. RF, IEEE 802.11a/b, IEEE 802.15.4, DECT, Linx, etc, which are commonly used nowadays in different RoboCup teams and propose improvements towards reliable and delay-critical wireless communication.
14.	Nielsen, Stig Anton, 1981, et al. (author) Propositional Architecture using Induced Representation 2014 In: What’s the Matter? Materiality and Materialism at the Age of Computation. - 9789608932067 ; , s. 297-312 Conference paper (peer-reviewed)abstract The paper describes a method and an approach to using sensor data, machine-learning and pattern recognition for proposing and guiding immediate modifications to the existing built environment. The proposed method; Induced Representation, consists of a few steps which we have identified as crucial for such an approach. The steps are A: data collection from the environment, B: machine cognition, learning, prediction, and, c: proposition, visualization, and embodied representations for quick implementation. In the paper we outline the factual and theoretical basis for this approach, and we present and discuss three experiments that each deal with the steps A, B and C.
15.	Xie, Haotian, et al. (author) Robust parallel predictive torque control with model reference adaptive estimator for im drives 2020 In: Proceedings - 2020 International Conference on Electrical Machines, ICEM 2020. ; 23 August 2020, s. 1219-1224 Conference paper (peer-reviewed)abstract This paper presents the robustness improvement for the proposed parallel structure predictive torque control (PPTC) via a MRA-based estimator. Although predictive torque control (PTC) has the merits of lower switching frequency and straightforward implementation, it inevitably suffers from the inherent drawbacks of high torque ripple and inappropriate tuning of the weighting parameter. To solve this issue, the proposed PPTC employs two homogeneous objective terms which are optimized in a parallel strucutre, to bypass the usage of weighting parameters. However, the parameter mismatches in the control plant will lead to the prediction torque and flux error, which further impacts the control behavior of the system. Therefore, this paper evaluates the parameter sensitivity for PPTC, aiming to improve robustness of the proposed algorithm with a MRA-based parameter estimator. Finally, the validity of the proposed scheme is confirmed through an experimental assessment.
16.	Yin, Hang, et al. (author) Policy Learning with Embedded Koopman Optimal Control Other publication (other academic/artistic)abstract Embedding an optimization process has been explored for imposing efficient and flexible policy structures. Existing work often build upon nonlinear optimization with explicitly unrolling of iteration steps, making policy inference prohibitively expensive for online learning and real-time control. Our approach embeds a linear-quadratic-regulator (LQR) formulation with a Koopman representation, thus exhibiting the tractability from a closed-form solution and richness from a non-convex neural network. We use a few auxiliary objectives and reparameterization to enforce optimality conditions of the policy that can be easily integrated to standard gradient-based learning. Our approach is shown to be effective for learning policies rendering an optimality structure and efficient reinforcement learning, including simulated pendulum control, 2D and 3D walking, and manipulation for both rigid and deformable objects. We also demonstrate real world application in a robot pivoting task.
17.	Selvaraj, Yuvaraj, 1990 (author) On Provably Correct Decision-Making for Automated Driving 2020 Licentiate thesis (other academic/artistic)abstract The introduction of driving automation in road vehicles can potentially reduce road traffic crashes and significantly improve road safety. Automation in road vehicles also brings several other benefits such as the possibility to provide independent mobility for people who cannot and/or should not drive. Many different hardware and software components (e.g. sensing, decision-making, actuation, and control) interact to solve the autonomous driving task. Correctness of such automated driving systems is crucial as incorrect behaviour may have catastrophic consequences. Autonomous vehicles operate in complex and dynamic environments, which requires decision-making and planning at different levels. The aim of such decision-making components in these systems is to make safe decisions at all times. The challenge of safety verification of these systems is crucial for the commercial deployment of full autonomy in vehicles. Testing for safety is expensive, impractical, and can never guarantee the absence of errors. In contrast, formal methods , which are techniques that use rigorous mathematical models to build hardware and software systems can provide a mathematical proof of the correctness of the system. The focus of this thesis is to address some of the challenges in the safety verification of decision-making in automated driving systems. A central question here is how to establish formal verification as an efficient tool for automated driving software development. A key finding is the need for an integrated formal approach to prove correctness and to provide a complete safety argument. This thesis provides insights into how three different formal verification approaches, namely supervisory control theory, model checking, and deductive verification differ in their application to automated driving and identifies the challenges associated with each method. It identifies the need for the introduction of more rigour in the requirement refinement process and presents one possible solution by using a formal model-based safety analysis approach. To address challenges in the manual modelling process, a possible solution by automatically learning formal models directly from code is proposed.
18.	Donde, Shrinish (author) Optimal Robot Localisation Techniques for Real World Scenarios 2019 Conference paper (other academic/artistic)abstract The following paper is a thorough review of our research based on the localisation of robots. It is an attempt to segregate the techniques, to locate the accurate position of robots in different environments and to discuss the superlative methods to localise such robots or in some cases an unmanned vehicle. The paper is divided into three real world problem statements and a thorough analysis of the best technique amongst other is made, for all the three conditions namely underwater, indoor and space, based on a number of parameters such as the cost, accuracy, efficiency, implementation of the technique and the environmental conditions around the robot. The primary reason to select these problem statements is due to the recent trends of research in these domains. Each of the technique has been chosen after discarding several previously applied techniques and an effective approach has been put forward for localising the robots in different areas.
19.	Ge, Yu, 1995, et al. (author) 5G SLAM Using the Clustering and Assignment Approach with Diffuse Multipath 2020 In: Sensors. - : MDPI AG. - 1424-8220. ; 20:16, s. 1-31 Journal article (peer-reviewed)abstract 5G communication systems operating above 24 GHz have promising properties for user localization and environment mapping. Existing studies have either relied on simplified abstract models of the signal propagation and the measurements, or are based on direct positioning approaches, which directly map the received waveform to a position. In this study, we consider an intermediate approach, which consists of four phases-downlink data transmission, multi-dimensional channel estimation, channel parameter clustering, and simultaneous localization and mapping (SLAM) based on a novel likelihood function. This approach can decompose the problem into simpler steps, thus leading to lower complexity. At the same time, by considering an end-to-end processing chain, we are accounting for a wide variety of practical impairments. Simulation results demonstrate the efficacy of the proposed approach.
20.	Hajieghrary, Hadi, 1983, et al. (author) Bayesian Optimization based Nonlinear Adaptive PID Design for Robust Control of the Joints at Mobile Manipulators 2022 In: IEEE International Conference on Automation Science and Engineering. - 2161-8070 .- 2161-8089. ; , s. 1009-1016 Conference paper (peer-reviewed)abstract In this paper, we propose to use a nonlinear adaptive PID controller to regulate the joint variables of a mobile manipulator. The motion of the mobile base forces undue disturbances on the joint controllers of the manipulator. In designing a conventional PID controller, one should make a trade-off between the performance and agility of the closed-loop system and its stability margins. The proposed nonlinear adaptive PID controller provides a mechanism to relax the need for such a compromise by adapting the gains according to the magnitude of the error without expert tuning. Therefore, we can achieve agile performance for the system while seeing damped overshoot in the output and track the reference as close as possible, even in the presence of external disturbances and uncertainties in the modeling of the system. We have employed a Bayesian optimization approach to choose the parameters of a nonlinear adaptive PID controller to achieve the best performance in tracking the reference input and rejecting disturbances. The results demonstrate that a well-designed nonlinear adaptive PID controller can effectively regulate a mobile manipulator’s joint variables while carrying an unspecified heavy load and an abrupt base movement occurs.
21.	Olsson, Magnus (author) Simulation and execution of autonomous robot systems 2002 Doctoral thesis (other academic/artistic)abstract Traditional off-line programming is not enough in order to use the full potential of virtual models and simulation system in industrial robot applications. The interface between off-line programming system and the robot controller is today restricted to program transfer. In this way a large amount of information is lost since typical robot programming languages is rather limited. If the virtual model could be accessed during the execution of the robot task, intelligent decisions could be made to avoid collisions, singularities, exceeding joint limits and poor process quality despite changes in the state of the robot workcell which not was anticipated in advance when the robot task was planned. Instead of a simple feedback loop to the robot movement, the virtual model is continuously updated so the new information together with previous knowledge is accumulated in a common format. High level re-planning of the robot task can then be automatically performed. An experimental system has been created that take advantage of the suggested approach. A commercial robot simulation system has been extended with new functionality for e.g. real time control of a physical robot, sensor feedback with automatic on-line calibration of the virtual model, robot tasks described in a high level language that can adapt to changes in the robot workcell and continuously supervision of the robot system to handle limitations without failing the task process. A modified industrial robot system have been used that allows low level joint control. Gas Metal Arc-welding (GMA) have been the target process during experiments. It is a complex process that needs continuous corrections in a delicate cooperation between robot and process equipment. A seam-tracker have mainly been used as sensor to illustrate the possibility to close the control loop in the virtual system.
22.	Ortiz Morales, Daniel, 1984-, et al. (author) Path-constrained motion analysis : an algorithm to understand human performance on hydraulic manipulators 2015 In: IEEE Transactions on Human-Machine Systems. - 2168-2291. ; 45:2, s. 187-199 Journal article (peer-reviewed)abstract We propose a novel method to analyze how human operators use hydraulic manipulators of heavy-duty equipment. The approach is novel in the sense that it applies knowledge of motion planning and optimization techniques used in robotics. As an example, we consider the case of operating a forestry crane. To that end, we use motion data that has been recorded during standard operation with the help of sensors and a data acquisition unit. The data backs up the notion that operators work by performing repeatable patterns observed in the trajectories of the manipulator's joints. We show how this nominal behavior is computed, and consequently this allow us to present the following: 1) an analytical procedure to analyze motions, 2) how to represent the "performance" of the operator in a 2D plot, 3) an example of how to use this information to suggest customized control settings, and 4) some complementary ideas needed for improving efficiency through automation.
23.	Rahal, Moustafa, et al. (author) RIS-Enabled NLoS Near-Field Joint Position and Velocity Estimation under User Mobility 2024 In: IEEE Journal on Selected Topics in Signal Processing. - 1941-0484 .- 1932-4553. ; In Press Journal article (peer-reviewed)abstract In the context of single-(BS) nonline- of-sight (NLoS) single-epoch localization with the aid of a reflective (RIS), this paper introduces a novel three-step algorithm that jointly estimates the position and velocity of a mobile (UE), while compensating for the Doppler effects observed in (NF) at the (RIS) elements over the short transmission duration of a sequence of (DL) pilot symbols. First, a low-complexity initialization procedure is proposed, relying in part on (FF) approximation and a static user assumption. Then, an alternating optimization procedure is designed to iteratively refine the velocity and position estimates, as well as the channel gain. %, at every step along the way. The refinement routines leverage small angle approximations and the linearization of the (RIS) response, accounting for both NF and mobility effects. We evaluate the performance of the proposed algorithm through extensive simulations under diverse operating conditions with regard to (SNR), (UE) mobility, uncontrolled multipath and (RIS)-(UE) distance. %We evaluate the performance of the proposed algorithm by means of simulations in a canonical scenario and Our results reveal remarkable performance improvements over the (SoTA) mobility-agnostic benchmark algorithm, while indicating convergence of the proposed algorithm to respective theoretical bounds on position and velocity estimation. %[BD: I remember we had this discussion with CHAL about the use of Algo1 as a variant of an existing algo (in 1st approximation). Does it still hold?], illustrating the dominating impact of the distance to the (RIS), as well as of (UE) velocity.
24.	Holstein, Tobias, et al. (author) Steps Towards Real-world Ethics for Self-driving Cars: Beyond the Trolley Problem 2021 In: Machine Law, Ethics, and Morality in the Age of Artificial Intelligence. - Hershey, Pennsylvania : IGI Global. - 9781799848943 - 9781799848950 ; , s. 85-107 Book chapter (other academic/artistic)abstract Research on self-driving cars is transdisciplinary and its different aspects have attracted interest in general public debates as well as among specialists. To this day, ethical discourses are dominated by the Trolley Problem, a hypothetical ethical dilemma that is by construction unsolvable. It obfuscates much bigger real-world ethical challenges in the design, development, and operation of self-driving cars. We propose a systematic approach that connects processes, components, systems, and stakeholders to analyze the real-world ethical challenges for the ecology of socio-technological system of self-driving cars. We take a closer look at the regulative instruments, standards, design, and implementations of components, systems, and services and we present practical social and ethical challenges that must be met and that imply novel expectations for engineering in car industry.
25.	Hagqvist, Petter (author) Non-intrusive instrumentation and estimation : Applications for control of an additive manufacturing process 2015 Doctoral thesis (other academic/artistic)abstract For integration of additive manufacturing into industrial production, there is a need for capable yet robust automation solutions. Such solutions are to ensure consistent process outputs, both with regard to deposit geometry and material properties. In this thesis, instrumentation and control solutions have been investigated for the laser metal wire deposition additive manufacturing process. This particular process is promising with regard to e.g. high deposition rates and negligible material waste. However, due to its inherent dynamics, it requires automatic control in order to prove competitive. A large number of process parameters affect the resulting quality of the deposit. Successful control of these parameters is crucial for turning laser metal wire deposition into an industrially tractable process. This requires relevant and reliable process information such as the temperature of the deposit and the positioning of the tool relative to the workpiece. Due to the particular requirements of instrumenting the process, only non-intrusive measurement methods are viable. In this thesis, such measurement solutions are presented that advance automatic control of the laser metal wire deposition. In response to the need for accurate temperature measurements for the process, a new temperature measurement method has been developed. By adopting the novel concept of temporal, rather than spectral, constraints for solving the multispectral pyrometry problem, it opens up for temperature measurements which compensates for e.g. an oxidising deposit. For maintaining a good deposition process in laser metal wire deposition, control of tool position and wire feed rate is required. Based on measurements of resistance through the weld pool, a simple yet well performing control system is presented in this thesis. The control system obtains geometrical input information from resistance measurements made in-situ, and feeds this information to an iterative learning controller. This results in a robust, cheap and practical control solution for laser metal wire deposition, which is suitable for industrial use and that can easily be retrofitted to existing equipment.
26.	Azkarate Fernández, Igor, et al. (author) Virtual commissioning of a robotic cell : An educational case study 2019 In: IEEE International Conference on Emerging Technologies and Factory Automation, ETFA. - : IEEE. - 9781728103037 - 9781728103020 - 9781728103044 ; , s. 820-825 Conference paper (peer-reviewed)abstract The emergence of software tools for testing control programs and virtual commissioning (VC) in industrial automation projects makes it possible to shorten lead times and improve product quality, but it also brings to light the need for competent technicians in these technologies. The academic environment can support the education of future professionals by reproducing and solving industrial problems in the classroom. This article presents a use case in which students work on a project to develop and validate the control system of a robotic cell. The study compares the conventional way of working against the use of a digital twin and exposes the benefits of it.
27.	Krook, Jonas, 1986 (author) Formal Methods and Safety for Automated Vehicles: Modeling, Abstractions, and Synthesis of Tactical Planners 2022 Doctoral thesis (other academic/artistic)abstract One goal of developing automated road vehicles is to completely free people from driving tasks. Automated vehicles with no human driver must handle all traffic situations that human drivers are expected to handle, possibly more. Though human drivers cause a lot of traffic accidents, they still have a very low accident and failure rate that automated vehicles must match. Tactical planners are responsible for making discrete decisions for the coming seconds or minutes. As with all subsystems in an automated vehicle, these planners need to be supported with a credible and convincing argument of their correctness. The planners interact with other road users in a feedback loop, so their correctness depends on their behavior in relation to other drivers and road users over time. One way to ascertain their correctness is to test the vehicles in real traffic. But to be sufficiently certain that a tactical planner is safe, it has to be tested on 255 million miles with no accidents. Formal methods can, in contrast to testing, mathematically prove that given requirements are fulfilled. Hence, these methods are a promising alternative for making credible arguments for tactical planners’ correctness. The topic of this thesis is the use of formal methods in the automotive industry to design safe tactical planners. What is interesting is both how automotive systems can be modeled in formal frameworks, and how formal methods can be used practically within the automotive development process. The main findings of this thesis are that it is viable to formally express desired properties of tactical planners, and to use formal methods to prove their correctness. However, the difficulty to anticipate and inspect the interaction of several desired properties is found to be an obstacle. Model Checking, Reactive Synthesis, and Supervisory Control Theory have been used in the design and development process of tactical planners, and these methods have their benefits, depending on the application. To be feasible and useful, these methods need to operate on both a high and a low level of abstraction, and this thesis contributes an automatic abstraction method that bridges this divide. It is also found that artifacts from formal methods tools may be used to convincingly argue that a realization of a tactical planner is safe, and that such an argument puts formal requirements on the vehicle’s other subsystems and its surroundings.
28.	La Hera, Pedro (author) Non-linear dynamics modelling description for simulating the behaviour of forestry cranes 2014 In: International Journal of Modelling, Identification and Control. - : Inderscience Publishers. - 1746-6172 .- 1746-6180. ; 21, s. 125 - 138 Journal article (peer-reviewed)abstract Model-based design is a standard framework widely adopted in modern industry. It is used for designing multi-domain engineering solutions based on computer-aided simulation technology. Currently, this approach is also being considered as a tentative method for designing modern heavy-duty machine technology. Under this motivation, our aim is to present how modelling techniques can be used for simulating dynamics of forestry machines. To this end, we consider a forestry crane, and propose mathematical models and calibration techniques, such that model-based methods can subsequently be applied. The complexity of the machine is represented by first principle laws, in which the mechanical system is modelled by Euler-Lagrange formulations, and the hydraulic system is modelled by principles of fluid dynamics. The calibration algorithms are performed by statistical algorithms based on linear and non-linear least-squares methods. The results of simulation show a significant correspondence between the simulated and observed variables, validating our procedures.
29.	Hemmingsson, Morten (author) Power System Oscillations - Detection, Estimation and Control 2003 Doctoral thesis (other academic/artistic)abstract The topic of this thesis is the electro-mechanical oscillations which to some extent always are present in a power system. The demand of electric power is ever increasing. At the same time, the tolerance of disruptions in the power supply is decreasing. The deregulated market together with distributed generation have then pushed the system to operate during circumstances for which it was not designed. To this we can then add that getting concessions for new lines becomes more and more difficult in densly populated areas. All these factors makes the electric power system operate with smaller safety margins. Decreasing these margins limits with sustained availability is achieved by the application of advanced monitoring and control methods. This thesis deals with this in several time-scales. When a large oscillation occurs it is important to detect it as fast as possible as the remedial action depends on if the current operating is due to a fault or an oscillation. In the thesis, a new method to distinguish these incidents from each other is presented. In a slower time-scale it is important to monitor the dynamics of the electro-mechanical modes. This information can be used to verify that simulations correspond to the real world behaviour. Real-time methods can also be used to alarm operators or arm special protection schemes if the power system enters undesired operating conditions. A number of methods are studied and then evaluated on three case studies. Finally, load modulation for damping enhancement is studied. It has previously been shown that modulation of active power at the transmission level increases the damping of the power system when correctly performed. Loads suitable for load modulation at the transmission level are rare and using actuators at the distribution level creates new problems. It is shown that it is possible to detect poor damping at the distribution level, thus reducing the need of communications. It is also shown how the variation of active and reactive power at the transmission level, caused by modulation of active power at the distribution level can be estimated without knowledge of the complete distribution network. This is most important as the active and reactive variations counteract each other. Finally load modulation at distribution level is evaluated on two test systems. It is shown that the damping is increased and that the influence of the reactive variation decreases the performance of load modulation. The degradation of the control scheme is, however, small in the studied cases.
30.	Ingildsen, Pernille (author) Realising full-scale control in wastewater treatment systems using in situ nutrient sensors 2002 Doctoral thesis (other academic/artistic)abstract Abstract A major change in paradigm is taking place in the operation of wastewater treatment plants as automatic process control is becoming feasible. This change is due to a number of different reasons, not least the development of online nutrient sensors, which measure the key parameters in the biological nutrient removal processes, i.e. ammonium, nitrate and phosphate. The thesis is about realising full-scale control in wastewater treatment systems using in situ nutrient sensors. The main conclusion of the work is that it is possible to significantly improve the operational performance in full-scale plants by means of relatively simple control structures and controllers based on in situ nutrient sensors. The in situ location should be emphasised as this results in short dead time, hence making simple feedback loops based on proportional and integral actions effective means to control the processes. This conclusion has been reached based on full-scale experiments, where various controllers and control structures for the biological removal of nitrogen and the chemical removal of phosphorous have been tested. The full-scale experiments have shown that it is possible to provide significant savings in energy consumption and precipitation chemicals consumption, reduction in sludge production and improvement of the effluent water quality. The conclusions are supported by model simulations using the COST benchmark simulation platform. The simulations are used for investigating issues regarding the interactions between the main control handles working in the medium time frame (relative gain array analysis). The simulations have also been used for testing various control structures and controllers. Controllers for the following types of control are suggested and tested: „h Control of aeration to obtain a certain effluent ammonium concentration; „h Control of internal recirculation flow rate to obtain maximum inorganic nitrogen removal; „h Control of external carbon dosage together with internal recirculation flow rate to obtain a certain effluent total inorganic nitrogen concentration; „h Optimisation of the choice of sludge age. Additionally, a procedure for implementing new control structures based on nutrient sensor has been proposed. The procedure involves an initial analysis phase, a monitoring phase, an experimenting phase and an automatic process control phase. An international survey with the aim to investigate the correspondence between ICA (instrumentation, control and automation) utilisation and plant performance has been carried out. The survey also gives insight into the current state of ICA applications at wastewater treatment plants.
31.	Lindstedt, Gunnar (author) Borrowing the Bat's Ear for Automation - Ultrasonic Measurements in an Industrial Environment 1996 Doctoral thesis (other academic/artistic)abstract This work focuses on measurement principles based on ultrasound for applications in industrial automation. The measurements made are of geometric nature. The methods used are when possible based on experience and/or inspiration from the study of bats. A platform for ultrasonic measurements, that allows a VME-based host computer to transmit and receive signals, with a considerable flexibility has been built. Sensor units utilizing both piezoelectric and electrostatic transducers are used. The dimensions of the units are about 10x10x7 centimeters. Frequencies in the range 40-200 kHz are used. The presented measurements include distance, flat surface spatial angle, object localization, object orientation, and object recognition. To make the methods robust matched filters are used in several of the measurements. Frequency sweeps are used to make the ultrasonic measurements more robust to various environmental parameters. Methods that utilize the new information provided by the frequency sweeps are also suggested.
32.	Peterson, Bo (author) Induction Machine Speed Estimation - Observations on Observers 1996 Doctoral thesis (other academic/artistic)abstract This work focuses on observers estimating flux linkage and speed for induction machines, mainly in the low speed region. With speed estimation, sensorless control is possible, meaning that the speed of induction machines without mechanical speed sensors can be controlled. The observer based sensorless drive system has superior dynamic performance compared to a system with an open loop frequency inverter, yet it is neither more complex nor expensive. Using mechanical equivalent models of the induction machine and observers, an accurate flux observer working in the entire speed region of the induction machine is presented. The flux observer is expanded into a combined flux and speed observer, measuring only stator current and voltage. A method for sensorless control is proposed, analyzed and experimentally verified. Observer and controller calculations are performed by a digital signal processor.
33.	Rosén, Christian (author) A Chemometric Approach to Process Monitoring and Control - With Applications to Wastewater Treatment Operation 2001 Doctoral thesis (other academic/artistic)abstract In this work, various aspects of multivariate monitoring and control of wastewater treatment operation are discussed. A number of important difficulties face operators and process engineers when handling online measurements from wastewater treatment processes. These include, for instance, a high number of correlated measurement variables, non-stationarities, nonlinearities and multiscale process behaviour. A systematic way to handle and analyse data is needed to effectively extract relevant information for monitoring and control. In this work, a chemometric approach is taken. Principal component analysis (PCA) is used to reduce both the dimensionality of the problem and the noise level in data. However, it is shown that basic PCA is not sufficient to describe the process adequately. There are mainly two reasons for this. First, the processes display a non-stationary behaviour due to the diurnal, weekly and seasonal variations in the composition of the wastewater. Second, disturbances and events occur at different time scales making basic PCA less suitable. The problem of non-stationary data is overcome using adaptive PCA in terms of updating of the scale parameters as well as the covariance structure. It is shown that adaptive PCA significantly improves the monitoring results as the model adapts to new process conditions without losing its ability to detect deviating process behaviour. To solve the problem of disturbances that occur at different time scales multiscale PCA is used. Multiscale PCA is a combination of multiresolution analysis and PCA. Measurement signals are decomposed into several time scales, and PCA models at each scale are identified. By doing so, the sensitivity to small process deviations that otherwise are obstructed by the diurnal variation is considerably increased. By omitting the lowest time scale from the analysis, the remaining time scales will inherently be (practically) stationary since this corresponds to using a highpass filtered version of the data. Another solution, where the PCA models at each scale are made adaptive is also presented. Using the monitoring results to adjust the process in a supervisory control manner is discussed. Two different methods are presented. The first is based on a multistep procedure. The current operational state is detected and classified using clustering in the principal component space. This information is used to determine appropriate setpoints for local controllers so that the process returns to what is considered normal operation. In the setpoint determination step, both static and dynamic models are used. The dynamic models are used within the framework of model predictive control (MPC). The multistep approach is best suited for extreme event control, since nonlinear and discrete control actions easily can be incorporated. The second method to integrate monitoring and control is based on PCA. Here, the inverse PCA model is used to directly calculate appropriate setpoints for the local controllers so that the process can be controlled to attain specified output requirements. The controller can be seen as a multivariate feedback controller implemented on top of the local control system. It is shown by simulation studies that both methods for supervisory control can successfully be used to control the process according to the control objectives.
34.	Samuelsson, Olof (author) Power System Damping - Structural Aspects of Controlling Active Power 1997 Doctoral thesis (other academic/artistic)abstract Environmental and economical aspects make it difficult to build new power lines and to reinforce existing ones. The continued growth in demand for electric power must therefore to a great extent be met by increased loading of available lines. A consequence is that power system damping is reduced, leading to a risk of poorly damped power oscillations between the generators. This thesis proposes the use of controlled active loads to increase damping of such electro-mechanical oscillations. The focus is on structural aspects of controller interaction and of sensor and actuator placement. On-off control based on machine frequency in a single machine infinite bus system is analysed using energy function analysis and phase plane plots. An on-off controller with estimated machine frequency as input has been implemented. At a field test it damped oscillations of a 0.9 MW hydro power generator by controlling a 20 kW load. The linear analysis uses two power system models with three and twenty-three machines respectively. Each damper has active power as output and local bus frequency or machine frequency as input. The power system simulator EUROSTAG is used both for generation of the linearized models and for time simulations. Measures of active power mode controllability and phase angle mode observability are obtained from the eigenvectors of the differential-algebraic models. The geographical variation in the network of these quantities is illustrated using the resemblance to bending modes of flexible mechanical structures. Eigenvalue sensitivities are used to determine suitable damper locations. A spring-mass equivalent to an inter-area mode provides analytical expressions, that together with the concept of impedance matching explain the structural behaviour of the power systems. For large gains this is investigated using root locus plots. The effect of using two dampers is studied. For the three machine system this is done for all combinations of the two gains in a certain range. In the twenty-three machine case one gain takes only two values as the other is varied.
35.	Svensson, Jörgen (author) Active Distributed Power Systems Functional Structures for Real-Time Operation of Sustainable Energy Systems 2006 Doctoral thesis (other academic/artistic)abstract Present power system will face great challenges in several areas depending on the market economy, extensive global integration and constant need for more electric power, which will force the system to operate much closer to its stability limits. Meeting these challenges may involve improving and complementing or even total restructuring of the power systems.New technologies are emerging such as renewable energy sources (RES) and power electronics, which in combination with information and automation will give opportunities to provide a number of services to the market. Market based operation may become a reality, where the management mechanism from contract to physical power transaction might get faster or even automated that could be an important advantage for renewable energy sources. Although, as several new generation units will be distributed and in same cases close to the consumption, local subsystems or distributed power systems would probably emerge to increase system reliability. Distributed power systems will function similarly to the present power system except for being down scaled and based on a high degree of automated functions. In such case the power system would in normal conditions still work similarly to present system where all distributed power systems are merged together. Only under special circumstances would affected distributed power systems disconnect, and later on, when appropriate, reconnect. In the meantime the individual distributed power system will run in ?stand-alone? mode.The thesis focus is related to real-time operation and control where a general information and functional structure for active distributed power systems has been studied. The structure is intended to provide future distributed power systems with a high degree in modularity, scalability, adaptability and autonomic behaviour enabling ?plug-and-produce?. Fundamental relations and principles are investigated as well as operation and strategy methods enabling autonomous operation of the systems. The basic solution is made by down-scaling the common centralized structure for operating a power system to several active distributed power systems that interact by well-defined hardware and software interfaces. In order to coordinate the system operation in real-time, a principal structure for distributed energy management system and information enabling market-based operation of renewable power sources is studied and adopted. Distributed functions for automated operation of various system configurations have been investigated to be able to automatically add and remove functionality due to changes in system configurations. The structure provides the means for condensing the necessary information for future needs on operation of new large RES (e.g. offshore wind power plants). The structure facilitates the expansion of new small RES (e.g. roof assembled solar power plants), where a new power unit is able to connect to an existing structure and then automatically adapt to the system. Well-defined system information and communication are necessary for the functioning of real-time operation. A part of the work includes studies on uniformed information and communication structures for different levels of communication, ranging from process- to market level communication. Although, most focus has been on the operational structure layer including several signals enabling the management of common generation units as well as intermittent power units such as RES.The information and functional structure is partly implemented in C++ modules and partly in the Dymola/Modelica simulation tool. Verifications are made both by simulation models and in a laboratory set-up. The verifications are performed for various system configurations where the simulation results agree with the experimental results.
36.	Saget, Sylvie (author) Language as a Tool: Acceptance-Based Pragmatics 2018 In: Workshop on Next Generation Human-Agent Interaction (NGHAI), 6th annual International Conference on Human-Agent Interaction (HAI 2018), Southampton, UK, 15-18th December 2018. Conference paper (other academic/artistic)abstract In this research, the communicative level of dialog or interaction is seen as the co-construction of a linguistic tool by dialog part- ners. The background mental attitude enabling such a practical reasoning is acceptance [3, 4]. The distinction between belief and acceptance is here based on their functional role: truth-oriented versus goal-oriented [8] - that is – by extension – encapsulating facts (declarative knowledge) versus tools (procedural knowledge). In order to precisely define this new mental attitude which is accep- tance, its relationship with belief and communicative action, this research aims at developing a rational model of dialog [13] as well as specifying a cognitive architecture. This approach contributes to the explanation of human behavior by refashioning the notion of cooperative speaker. This enables to mix reasoning-based approaches and reuse-based approach of collaborative view of dialog. Additionally, the notion of Acceptance and more especially its social counterpart - Collective Acceptance respects the properties of co-constructed linguistic tools. Enabling a system to both rely different perspectives (its own point of view, their addresses one or common/shared beliefs) or on existing linguistic tools built during the preceding interactions enhances system’s flexibility and rationality [5, 14].
37.	Schmidt, Bernard, 1981-, et al. (author) Automatic work objects calibration via a global-local camera system 2014 In: Robotics and Computer-Integrated Manufacturing. - : Elsevier. - 0736-5845 .- 1879-2537. ; 30:6, s. 678-683 Journal article (peer-reviewed)abstract In a human–robot collaborative manufacturing application where a work object can be placed in an arbitrary position, there is a need to calibrate the actual position of the work object. This paper presents an approach for automatic work-object calibration in flexible robotic systems. The approach consists of two modules: a global positioning module based on fixed cameras mounted around robotic workspace, and a local positioning module based on the camera mounted on the robot arm. The aim of the global positioning is to detect the work object in the working area and roughly estimate its position, whereas the local positioning is to define an object frame according to the 3D position and orientation of the work object with higher accuracy. For object detection and localization, coded visual markers are utilized. For each object, several markers are used to increase the robustness and accuracy of the localization and calibration procedure. This approach can be used in robotic welding or assembly applications.
38.	Ortiz Catalan, Max Jair, 1982 (author) Towards Natural Control of Artificial Limbs 2014 Doctoral thesis (other academic/artistic)abstract The use of implantable electrodes has been long thought as the solution for a more natural control of artificial limbs, as these offer access to long-term stable and physiologically appropriate sources of control, as well as the possibility to elicit appropriate sensory feedback via neurostimulation. Although these ideas have been explored since the 1960’s, the lack of a long-term stable human-machine interface has prevented the utilization of even the simplest implanted electrodes in clinically viable limb prostheses.In this thesis, a novel human-machine interface for bidirectional communication between implanted electrodes and the artificial limb was developed and clinically implemented. The long-term stability was achieved via osseointegration, which has been shown to provide stable skeletal attachment. By enhancing this technology as a communication gateway, the longest clinical implementation of prosthetic control sourced by implanted electrodes has been achieved, as well as the first in modern times. The first recipient has used it uninterruptedly in daily and professional activities for over one year. Prosthetic control was found to improve in resolution while requiring less muscular effort, as well as to be resilient to motion artifacts, limb position, and environmental conditions.In order to support this work, the literature was reviewed in search of reliable and safe neuromuscular electrodes that could be immediately used in humans. Additional work was conducted to improve the signal-to-noise ratio and increase the amount of information retrievable from extraneural recordings. Different signal processing and pattern recognition algorithms were investigated and further developed towards real-time and simultaneous prediction of limb movements. These algorithms were used to demonstrate that higher functionality could be restored by intuitive control of distal joints, and that such control remains viable over time when using epimysial electrodes. Lastly, the long-term viability of direct nerve stimulation to produce intuitive sensory feedback was also demonstrated.The possibility to permanently and reliably access implanted electrodes, thus making them viable for prosthetic control, is potentially the main contribution of this work. Furthermore, the opportunity to chronically record and stimulate the neuromuscular system offers new venues for the prediction of complex limb motions and increased understanding of somatosensory perception. Therefore, the technology developed here, combining stable attachment with permanent and reliable human-machine communication, is considered by the author as a critical step towards more functional artificial limbs.
39.	Ciccozzi, Federico, 1983-, et al. (author) Engineering the software of robotic systems 2017 In: Proceedings - 2017 IEEE/ACM 39th International Conference on Software Engineering Companion, ICSE-C 2017. - : IEEE. ; , s. 507-508 Conference paper (peer-reviewed)abstract The production of software for robotic systems is often case-specific, without fully following established engineering approaches. Systematic approaches, methods, models, and tools are pivotal for the creation of robotic systems for real-world applications and turn-key solutions. Well-defined (software) engineering approaches are considered the 'make or break' factor in the development of complex robotic systems. The shift towards well-defined engineering approaches will stimulate component supply-chains and significantly reshape the robotics marketplace. The goal of this technical briefing is to provide an overview on the state of the art and practice concerning solutions and open challenges in the engineering of software required to develop and manage robotic systems. Model-Driven Engineering (MDE) is discussed as a promising technology to raise the level of abstraction, promote reuse, facilitate integration, boost automation and promote early analysis in such a complex domain.
40.	Lindroos, Ola, et al. (author) Estimating the position of the harvester head : a key step towards the precision forestry of the future? 2015 In: Croatian Journal of Forest Engineering. - Zagreb : University of Zagreb. - 1845-5719 .- 1848-9672. ; 36:2, s. 147-164 Journal article (peer-reviewed)abstract Modern harvesters are technologically sophisticated, with many useful features such as the ability to automatically measure stem diameters and lengths. This information is processed in real time to support value optimization when cutting stems into logs. It can also be transferred from the harvesters to centralized systems and used for wood supply management. Such information management systems have been available since the 1990s in Sweden and Finland, and are constantly being upgraded. However, data on the position of the harvester head relative to the machine are generally not recorded during harvesting. The routine acquisition and analysis of such data could offer several opportunities to improve forestry operations and related processes in the future. Here, we analyze the possible benefits of having this information, as well as the steps required to collect and process it. The benefits and drawbacks of different sensing technologies are discussed in terms of potential applications, accuracy and cost. We also present the results of preliminary testing using two of the proposed methods. Our analysis indicates that an improved scope for mapping and controlling machine movement is the main benefit that is directly related to the conduct of forestry operations. In addition, there are important indirect benefits relating to ecological mapping. Our analysis suggests that both of these benefits can be realized by measuring the angles of crane joints or the locations of crane segments and using the resulting information to compute the head's position. In keeping with our findings, two companies have recently introduced sensor equipped crane solutions.
41.	Gidlund, Mikael, 1972-, et al. (author) Guest Editorial : Security, Privacy, and Trust for Industrial Internet of Things 2020 In: IEEE Transactions on Industrial Informatics. - Piscataway, NJ : IEEE. - 1551-3203 .- 1941-0050. ; 16:1, s. 625-628 Journal article (other academic/artistic)abstract This Special Section on "Security, privacy, and trust for Industrial Internet of Things" of the IEEE Transactions on Industrial Informatics (TII) highlights the main research challenges in the industrial Internet of Things (IoT) security, privacy, and trust. The designated nine high-quality research articles cover a wide range of the special section theme, including innovative solutions and novel technologies. These articles are briefly summarized. © 2019 IEEE.
42.	Jiang, Frank, et al. (author) Ensuring safety for vehicle parking tasks using Hamilton-Jacobi reachability analysis 2020 In: Proceedings of the IEEE Conference on Decision and Control. - : Institute of Electrical and Electronics Engineers Inc.. ; , s. 1416-1421 Conference paper (peer-reviewed)abstract In this paper, we propose an approach for ensuring the safety of a vehicle throughout a parking task, even when the vehicle is being operated at varying levels of automation. We start by specifying a vehicle parking task using linear temporal logic formulae that can be model checked for feasibility. The model-checking is facilitated by the construction of a temporal logic tree via Hamilton-Jacobi reachability analysis. Once we know the parking task is feasible for our vehicle model, we utilize the constructed temporal logic tree to directly synthesize control sets. Our approach synthesizes control sets that are least-restrictive in the context of the specification, since they permit any control inputs that are guaranteed not to violate the specification. This least-restrictive characteristic allows for the application of our approach to vehicles under different modes of operation (e.g., human-in-the-loop shared autonomy or fully-automated schemes). Implementing in both simulation and on hardware, we demonstrate the approach's potential for ensuring the safety of vehicles throughout parking tasks, whether they are operated by humans or automated driving systems.
43.	Larsson, L. Viktor (author) Control Aspects of Complex Hydromechanical Transmissions : with a Focus on Displacement Control 2017 Licentiate thesis (other academic/artistic)abstract This thesis deals with control aspects of complex hydromechanical transmissions. The overall purpose is to increase the knowledge of important aspects to consider during the development of hydromechanical transmissions to ensure transmission functionality. These include ways of evaluating control strategies in early design stages as well as dynamic properties and control aspects of displacement controllers, which are key components in these systems.Fuel prices and environmental concerns are factors that drive research on propulsion in heavy construction machinery. Hydromechanical transmissions are strong competitors to conventional torque-converter transmissions used in this application today. They offer high efficiency and wide speed/torque conversion ranges, and may easily be converted to hybrids that allow further fuel savings through energy recuperation. One challenge with hydromechanical transmissions is that they offer many different configurations, which in turn makes it important to enable evaluation of control aspects in early design stages. In this thesis, hardware-in-the-loop simulations, which blend hardware tests and standard software-based simulations, are considered to be a suitable method. A multiple-mode transmission applied to a mid-sized construction machine is modelled and evaluated in offline simulations as well as in hardware-in-the-loopsimulations.Hydromechanical transmissions rely on efficient variable pumps/motors with fast, accurate displacement controllers. This thesis studies the dynamic behaviour of the displacement controller in swash-plate axial-piston pumps/motors. A novel control approach in which the displacement is measured with an external sensor is proposed. Performance and limitations of the approach are tested in simulations and in experiments. The experiments showed a significantly improved performance with a controller that is slightly more advanced than a standard proportional controller. The implementation of the controller allows simple tuning and good predictability of the displacement response.
44.	Sanz, Fernando Garcia, et al. (author) Exploring Approaches for Heterogeneous Transfer Learning in Dynamic Networks 2022 In: Proceedings Of The Ieee/Ifip Network Operations And Management Symposium 2022. - : Institute of Electrical and Electronics Engineers (IEEE). - 9781665406017 Conference paper (peer-reviewed)abstract Maintaining machine-learning models for prediction of service performance is challenging, especially in dynamic network and cloud environments where route changes occur, and execution environments can be scaled and migrated. Recently, transfer learning has been proposed as an approach for leveraging already learned knowledge in a new environment. The challenge is that the new environment may be significantly different from the one the model is trained in, and transferred from, with respect to data distributions and dimensionality. In this paper, we introduce heterogeneous transfer learning in the context of dynamic environments and show its efficiency in predicting service performance. We propose two heterogeneous transfer-learning approaches and evaluate them on several neural-network architectures and scenarios. The scenarios are a natural consequence of network and cloud infrastructure reorchestration. We quantify the transfer gain, and empirically show positive gain in a majority of cases for both approaches. Furthermore, we study the impact of neural-network configurations on the transfer gain, providing tradeoff insights. The evaluation of the approaches is performed using data traces collected from a cloud testbed that runs two services under multiple realistic load conditions.
45.	Selvaraj, Yuvaraj, 1990, et al. (author) Verification of Decision Making Software in an Autonomous Vehicle: An Industrial Case Study 2019 In: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics). - Cham : Springer International Publishing. - 1611-3349 .- 0302-9743. ; 11687 LNCS, s. 143-159 Conference paper (peer-reviewed)abstract Correctness of autonomous driving systems is crucial as incorrect behaviour may have catastrophic consequences. Many different hardware and software components (e.g. sensing, decision making, actuation, and control) interact to solve the autonomous driving task, leading to a level of complexity that brings new challenges for the formal verification community. Though formal verification has been used to prove correctness of software, there are significant challenges in transferring such techniques to an agile software development process and to ensure widespread industrial adoption. In the light of these challenges, the identification of appropriate formalisms, and consequently the right verification tools, has significant impact on addressing them. In this paper, we evaluate the application of different formal techniques from supervisory control theory, model checking, and deductive verification to verify existing decision and control software (in development) for an autonomous vehicle. We discuss how the verification objective differs with respect to the choice of formalism and the level of formality that can be applied. Insights from the case study show a need for multiple formal methods to prove correctness, the difficulty to capture the right level of abstraction to model and specify the formal properties for the verification objectives.
46.	Appelgren, Jessica, et al. (author) Autonoma vapensystem – dagens debatt och en väg framåt : tekniska, legala och etiska aspekter 2022 Reports (other academic/artistic)abstract Framstegen inom AI väcker frågor kring den militära tilllämpningen av tekniken och tillåten grad av automatisering av vapensystem. Debatten om AI i militära tillämpningar förs både av civilsamhällets organisationer och av stater. Debatten började med det mycket specifika ifrågasättandet av fullt autonoma vapensystem, ofta kallade Lethal Autonomous Weapon Systems (LAWS), men debatten och ifrågasättandet har vidgats till att omfatta införandet av AI i militära tillämpningar. Diskussionen är mångfacetterad och präglas av flera olika perspektiv på ställningstaganden och argumentation. Autonoma system har många användningsområden i militära tillämpningar och det är viktigt att förstå hur integrationen av högautomatiserade system ska kunna göras medavseende på de rättsliga ramverk som försvaret lyder under.Även om debatten till viss del har sitt ursprung i det senaste decenniets drönarkrigföring är de flesta parter överens omatt dagens debatt snarare handlar om framtida teknik. De tekniska, militära och juridiska aspekterna är centrala i diskussionen men även etiska, psykologiska och säkerhetspolitiska aspekter tar plats i debatten.
47.	Landscheidt, Steffen, et al. (author) Automation Practices in Wood Product Industries : Lessons learned, current Practices and Future Perspectives 2016 In: The 7th Swedish Production Symposium SPS, 25-27 October, 2016, Lund, Sweden. - Lund, Sweden : Lund University. Conference paper (peer-reviewed)abstract Wood product industries are a cornerstone of the Swedish industry and contribute vastly to the total Swedish export value. Wood as material itself has a promising perspective of becoming one of the most valuable resources. Sweden in particular has a long tradition and the knowledge of how to cultivate forests. In comparison to the highly automated forest industries, production systems of Swedish wood products industries are mostly characterized by a low degree of automation, tough manual labour and a relative low competency of the workforce. Facing fiercer competition on a global market, Swedish wood product industries are starting to lose touch with wood working industries in other industrialized European countries. Based upon established literature, this paper systematizes the status of automation practices in wood processing industries. The outcome of this study also outlines the expected effects and the future perspectives of digitalization and robotic automation for wood processing industries in high-1are not ready to implement the necessary standards to enter Industry 4.0. Not only are the technical prerequisites not fulfilled, but also a lack of appropriate production organization, logistics and economic basis is affecting negatively.
48.	Saget, Sylvie, et al. (author) Developing strategies to stop bullying: Design considerations for an artificial training center 2019 In: Dialog for Good (DiGo) 2019: Workshop on Speech and Language Technology Serving Society, Stockholm, 10 September, 2019. Conference paper (other academic/artistic)abstract Reporting incidents to an adult is the top recommendation for youth victims facing bullying. At the same time, victims need to develop strategies to use when they are facing their offenders: counter aggression and making a safety plan. This paper presents design considerations for a conversational system being a training center for a victim to learn and try such strategies. We first detail what is bullying and existing preventive measures. We then detail specific features of such a conversational system and we define a set of functionalities and dialog design considerations required to ensure compliance with the preceding features. We close with the presentation of a simple illustrative implementation.
49.	Satpute, Sumeet G., 1987-, et al. (author) Optimization Based Safe and Efficient Trajectory Planning in Proximity of an Asteroid 2020 In: 2020 7th International Conference on Control, Decision and Information Technologies (CoDIT). - : IEEE. ; , s. 939-945 Conference paper (peer-reviewed)abstract This article focuses on a spacecraft trajectory planning algorithm that allows observation of multiple site locations on the asteroid surface, while avoiding any collision with debris objects trapped in the asteroid’s gravity field. Asteroids provide a challenging target for satellite based visual coverage missions, since they are partially illuminated, rotating, irregular shaped celestial bodies with a low but also irregular gravity field. For addressing this problem, an optimization approach for visual coverage is proposed with an objective to determine the sequence of the imaging site locations and the associated safe and fuel efficient trajectories, while considering rotational dynamics of the asteroid, changing illumination condition for each site, irregular gravity constraints of the asteroid and the safe separation distance from the moving debris object. Numerical simulations are performed to demonstrate the ability of the trajectory planner to ensure successful optimal coverage of all the desired asteroid site locations.
50.	Remouit, Flore, 1988-, et al. (author) Thruster model for Observation Class Remotely Operated Vehicle In: Ocean Engineering. - 0029-8018 .- 1873-5258. Journal article (peer-reviewed)abstract For any small company or research group in offshore renewable energy, the costs to invest into Remotely Operate Vehicles (ROVs) for offshore operations are highly significant. There is however a potential to adapt and equip Observation Class ROVs (OCROVs) in order to make them perform light tasks, such as cable connection. OpenROV is a small and light OCROV with open source software, making it easy to implement tools, such as an autopilot. In this paper a model of the autopilot is presented. To be tested, it needs a model of the thrusters of the OpenROV. Those thrusters are hence tested, modelled in Simulink, and the experimental results are compared to the Matlab model.

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