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  • 1.
    Ahlberg, Carl
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Embedded high-resolution stereo-vision of high frame-rate and low latency through FPGA-acceleration2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Autonomous agents rely on information from the surrounding environment to act upon. In the array of sensors available, the image sensor is perhaps the most versatile, allowing for detection of colour, size, shape, and depth. For the latter, in a dynamic environment, assuming no a priori knowledge, stereo vision is a commonly adopted technique. How to interpret images, and extract relevant information, is referred to as computer vision. Computer vision, and specifically stereo-vision algorithms, are complex and computationally expensive, already considering a single stereo pair, with results that are, in terms of accuracy, qualitatively difficult to compare. Adding to the challenge is a continuous stream of images, of a high frame rate, and the race of ever increasing image resolutions. In the context of autonomous agents, considerations regarding real-time requirements, embedded/resource limited processing platforms, power consumption, and physical size, further add up to an unarguably challenging problem.

    This thesis aims to achieve embedded high-resolution stereo-vision of high frame-rate and low latency, by approaching the problem from two different angles, hardware and algorithmic development, in a symbiotic relationship. The first contributions of the thesis are the GIMME and GIMME2 embedded vision platforms, which offer hardware accelerated processing through FGPAs, specifically targeting stereo vision, contrary to available COTS systems at the time. The second contribution, toward stereo vision algorithms, is twofold. Firstly, the problem of scalability and the associated disparity range is addressed by proposing a segment-based stereo algorithm. In segment space, matching is independent of image scale, and similarly, disparity range is measured in terms of segments, indicating relatively few hypotheses to cover the entire range of the scene. Secondly, more in line with the conventional stereo correspondence for FPGAs, the Census Transform (CT) has been identified as a recurring cost metric. This thesis proposes an optimisation of the CT through a Genetic Algorithm (GA) - the Genetic Algorithm Census Transform (GACT). The GACT shows promising results for benchmark datasets, compared to established CT methods, while being resource efficient.

  • 2.
    Ahmed, Mobyen Uddin
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Altarabichi, Mohammed Ghaith
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Begum, Shahina
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Ginsberg, Fredrik
    Mälardalens högskola, Västerås, Sweden.
    Glaes, Robert
    Mälardalens högskola, Västerås, Sweden.
    Östgren, Magnus
    Mälardalens högskola, Västerås, Sweden.
    Rahman, Hamidur
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Sorensen, Magnus
    Mälardalens högskola, Västerås, Sweden.
    Avision-based indoor navigation system for individuals with visual impairment2019In: International Journal of Artificial Intelligence, ISSN 0974-0635, E-ISSN 0974-0635, Vol. 17, no 2, p. 188-201Article in journal (Refereed)
    Abstract [en]

    Navigation and orientation in an indoor environment are a challenging task for visually impaired people. This paper proposes a portable vision-based system to provide support for visually impaired persons in their daily activities. Here, machine learning algorithms are used for obstacle avoidance and object recognition. The system is intended to be used independently, easily and comfortably without taking human help. The system assists in obstacle avoidance using cameras and gives voice message feedback by using a pre-trained YOLO Neural Network for object recognition. In other parts of the system, a floor plane estimation algorithm is proposed for obstacle avoidance and fuzzy logic is used to prioritize the detected objects in a frame and generate alert to the user about possible risks. The system is implemented using the Robot Operating System (ROS) for communication on a Nvidia Jetson TX2 with a ZED stereo camera for depth calculations and headphones for user feedback, with the capability to accommodate different setup of hardware components. The parts of the system give varying results when evaluated and thus in future a large-scale evaluation is needed to implement the system and get it as a commercialized product in this area.

  • 3.
    Akalin, Neziha
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kiselev, Andrey
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    An Evaluation Tool of the Effect of Robots in Eldercare on the Sense of Safety and Security2017In: Social Robotics: 9th International Conference, ICSR 2017, Tsukuba, Japan, November 22-24, 2017, Proceedings / [ed] Kheddar, A.; Yoshida, E.; Ge, S.S.; Suzuki, K.; Cabibihan, J-J:, Eyssel, F:, He, H., Springer International Publishing , 2017, p. 628-637Conference paper (Refereed)
    Abstract [en]

    The aim of the study presented in this paper is to develop a quantitative evaluation tool of the sense of safety and security for robots in eldercare. By investigating the literature on measurement of safety and security in human-robot interaction, we propose new evaluation tools. These tools are semantic differential scale questionnaires. In experimental validation, we used the Pepper robot, programmed in the way to exhibit social behaviors, and constructed four experimental conditions varying the degree of the robot’s non-verbal behaviors from no gestures at all to full head and hand movements. The experimental results suggest that both questionnaires (for the sense of safety and the sense of security) have good internal consistency.

  • 4.
    Akalin, Neziha
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kiselev, Andrey
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    The Relevance of Social Cues in Assistive Training with a Social Robot2018In: 10th International Conference on Social Robotics, ICSR 2018, Proceedings / [ed] Ge, S.S., Cabibihan, J.-J., Salichs, M.A., Broadbent, E., He, H., Wagner, A., Castro-González, Á., Springer , 2018, p. 462-471Conference paper (Refereed)
    Abstract [en]

    This paper examines whether social cues, such as facial expressions, can be used to adapt and tailor a robot-assisted training in order to maximize performance and comfort. Specifically, this paper serves as a basis in determining whether key facial signals, including emotions and facial actions, are common among participants during a physical and cognitive training scenario. In the experiment, participants performed basic arm exercises with a social robot as a guide. We extracted facial features from video recordings of participants and applied a recursive feature elimination algorithm to select a subset of discriminating facial features. These features are correlated with the performance of the user and the level of difficulty of the exercises. The long-term aim of this work, building upon the work presented here, is to develop an algorithm that can eventually be used in robot-assisted training to allow a robot to tailor a training program based on the physical capabilities as well as the social cues of the users.

  • 5.
    Akan, Batu
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Planning and Sequencing Through Multimodal Interaction for Robot Programming2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Over the past few decades the use of industrial robots has increased the efficiency as well as the competitiveness of several sectors. Despite this fact, in many cases robot automation investments are considered to be technically challenging. In addition, for most small and medium-sized enterprises (SMEs) this process is associated with high costs. Due to their continuously changing product lines, reprogramming costs are likely to exceed installation costs by a large margin. Furthermore, traditional programming methods of industrial robots are too complex for most technicians or manufacturing engineers, and thus assistance from a robot programming expert is often needed. The hypothesis is that in order to make the use of industrial robots more common within the SME sector, the robots should be reprogrammable by technicians or manufacturing engineers rather than robot programming experts. In this thesis, a novel system for task-level programming is proposed. The user interacts with an industrial robot by giving instructions in a structured natural language and by selecting objects through an augmented reality interface. The proposed system consists of two parts: (i) a multimodal framework that provides a natural language interface for the user to interact in which the framework performs modality fusion and semantic analysis, (ii) a symbolic planner, POPStar, to create a time-efficient plan based on the user's instructions. The ultimate goal of this work in this thesis is to bring robot programming to a stage where it is as easy as working together with a colleague.This thesis mainly addresses two issues. The first issue is a general framework for designing and developing multimodal interfaces. The general framework proposed in this thesis is designed to perform natural language understanding, multimodal integration and semantic analysis with an incremental pipeline. The framework also includes a novel multimodal grammar language, which is used for multimodal presentation and semantic meaning generation. Such a framework helps us to make interaction with a robot easier and more natural. The proposed language architecture makes it possible to manipulate, pick or place objects in a scene through high-level commands. Interaction with simple voice commands and gestures enables the manufacturing engineer to focus on the task itself, rather than the programming issues of the robot. The second issue addressed is due to inherent characteristics of communication with the use of natural language; instructions given by a user are often vague and may require other actions to be taken before the conditions for applying the user's instructions are met. In order to solve this problem a symbolic planner, POPStar, based on a partial order planner (POP) is proposed. The system takes landmarks extracted from user instructions as input, and creates a sequence of actions to operate the robotic cell with minimal makespan. The proposed planner takes advantage of the partial order capabilities of POP to execute actions in parallel and employs a best-first search algorithm to seek the series of actions that lead to a minimal makespan. The proposed planner can also handle robots with multiple grippers, parallel machines as well as scheduling for multiple product types.

  • 6.
    Andersson, Carina
    Mälardalen University, School of Innovation, Design and Engineering.
    Informationsdesign i tillståndsövervakning: En studie av ett bildskärmsbaserat användargränssnitt för tillståndsövervakning och tillståndsbaserat underhåll2010Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This research concerns the information design and visual design of graphical user interfaces (GUI) in the condition monitoring and condition-based maintenance (CBM) of production equipment. It also concerns various communicative aspects of a GUI, which is used to monitor the condition of assets. It applies to one Swedish vendor and its intentions to design information. In addition, it applies to the interaction between the GUI and its individual visual elements, as well as the communication between the GUI and the users (in four Swedish paper mills).

    The research is performed as a single case study. Interviews and observations have been the main methods for data collection. Empirical data is analyzed with methods inferred to semiotics, rhetoric and narratology. Theories in information science and regarding remediation are used to interpret the user interface design.

    The key conclusion is that there are no less than five different forms of information, all important when determining the conditions of assets. These information forms include the words, images and shapes in the GUI, the machine components and peripherals equipment, the information that takes form when personnel communicate machine conditions, the personnel’s subjective associations, and the information forms that relate to the personnel's actions and interactions.

    Preventive technicians interpret the GUI-information individually and collectively in relation to these information forms, which influence their interpretation and understanding of the GUI information. Social media in the GUI makes it possible to represent essential information that takes form when employees communicate a machine’s condition. Photographs may represent information forms as a machine’s components, peripherals, and local environment change over time. Moreover, preventative technicians may use diagrams and photographs in the GUI to change attitudes among the personnel at the mills and convince them, for example, of a machine’s condition or the effectiveness of CBM as maintenance policy.

  • 7.
    Dehnavi, S.
    et al.
    School of ECE, College of Engineering, University of Tehran, Iran; School of Innovation, Design and Engineering, Mälardalen University, Västerås, Sweden.
    Sedaghatbaf, Ali
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Salmani, B.
    Department of Informatik, RWTH-Aachen University, Germany.
    Sirjani, Marjan
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Kargahi, M.
    School of ECE, College of Engineering, University of Tehran, Iran.
    Khamespanah, E.
    School of ECE, College of Engineering, University of Tehran, Iran; School of Computer Science, Reykjavik University, Iceland.
    Towards an actor-based approach to design verified ROS-based robotic programs using rebeca2019In: Procedia Computer Science, Elsevier B.V. , 2019, Vol. 155, p. 59-68Conference paper (Refereed)
    Abstract [en]

    Robotic technology helps humans in different areas such as manufacturing, health care and education. Due to the ubiquitous revolution, today's focus is on mobile robots and their applications in a variety of cyber-physical systems. ROS is a wll-known and powerful middleware that facilitates software development for mobile robots. However, this middleware does not support assuring properties such as timeliness and safety of ROS-based software. In this paper we present an integration of Timed Rebeca modeling language with ROS to synthesize verified robotic software. First, a conceptual model of robotic programs is developed using Timed Rebeca. After verifying a set of user-defined correctness properties on this model, it is translated to a ROS program automatically. Experiments on some small-scale case studies illustrates the applicability of the proposed integration method. 

  • 8.
    Ekström, Per
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Eriksson, Elisabeth
    Mälardalen University, School of Innovation, Design and Engineering.
    REDUNDANT FIRMWARE TEST SETUP IN SIMULATION AND HARDWARE: A FEASIBILITY STUDY2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A reliable embedded real-time system has many requirements to fulfil. It must meet target deadlines in a number of situations, most of them in a situation that puts heavy stress on the system. To meet these demands, numerous tests have been created which test the hardware for any possible errors the developers might think of, in order to maximise system reliability and stability. These tests will take a lot of time to execute, and as system complexity grows, more tests are introduced leading to even longer testing times. In this thesis, a method to reduce the testing time of the software and, to a lesser extent, the hardware is examined. By using the full system simulator Simics, an existing industry system from ABB was integrated and tests were performed. A proof of concept test suite for automatic redundancy tests was also implemented. By looking at the test results, it was concluded that the method shows promise. However, problems with the average latency and performance troubles with Simics shows that more work must be put into this research before the system can be run at full speed.

  • 9.
    Eriksson, Therése
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Mahmoud Abdelnaeim, Mohamed
    Mälardalen University, School of Innovation, Design and Engineering.
    Waveform clustering - Grouping similar power system events2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Over the last decade, data has become a highly valuable resource. Electrical power grids deal with large quantities of data, and continuously collect this for analytical purposes. Anomalies that occur within this data is important to identify since they could cause nonoptimal performance within the substations, or in worse cases damage to the substations themselves. However, large datasets in the order of millions are hard or even impossible to gain a reasonable overview of the data manually. When collecting data from electrical power grids, predefined triggering criteria are often used to indicate that an event has occurred within the specific system. This makes it difficult to search for events that are unknown to the operator of the deployed acquisition system. Clustering, an unsupervised machine learning method, can be utilised for fault prediction within systems generating large amounts of multivariate time-series data without labels and can group data more efficiently and without the bias of a human operator. A large number of clustering techniques exist, as well as methods for extracting information from the data itself, and identification of these was of utmost importance. This thesis work presents a study of the methods involved in the creation of such a clustering system which is suitable for the specific type of data. The objective of the study was to identify methods that enables finding the underlying structures of the data and cluster the data based on these. The signals were split into multiple frequency sub-bands and from these features could be extracted and evaluated. Using suitable combinations of features the data was clustered with two different clustering algorithms, CLARA and CLARANS, and evaluated with established quality analysis methods. The results indicate that CLARA performed overall best on all the tested feature sets. The formed clusters hold valuable information such as indications of unknown events within the system, and if similar events are clustered together this can assist a human operator further to investigate the importance of the clusters themselves. A further conclusion from the results is that research into the use of more optimised clustering algorithms is necessary so that expansion into larger datasets can be considered.

  • 10.
    Eriksson, Yvonne
    et al.
    Mälardalen University, School of Innovation, Design and Engineering. Informationsdesign.
    Porathe, Thomas
    Mälardalen University, School of Innovation, Design and Engineering. Informationsdesign.
    How children read pictures and text in some science school books: eye-tracking studies2008In: Proceedings of the Scandinavian Workshop of Applied Eye-Tracking (SWAET 2008, 2008Conference paper (Refereed)
    Abstract [en]

    In an eye-tracking pilot-project we have asked 6 children, age of 11, to read an opening,

    from a geography book for grade five. The aim of the study was to investigate

    the role of illustrations in text-books and to what extent they contribute to the learning

    process.

  • 11.
    Florin, Ulrika
    Mälardalen University, School of Innovation, Design and Engineering.
    Från idé till gestaltningsförslag: fallstudie från Projekt Konstpaus2010Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Abstract

    The overall intention of this research project is to increase knowledge regarding design processes in general and artists' design processes specifically. The research is carried out as a case study based on the sketch processes that took place within Projekt Konstpaus (The Art Break Project). The sketches, or suggested designs, are the main objective for analysis and consideration in this study.

    Projekt Konstpaus (The Art Break Project) is a development pro­ject partially financed by the European Union (EU). The vision of the project embodied equality, multiculturalism and sustainable community development. The municipality of Strängnäs, Sweden was the leading partner in the project and provided the necessary support for the project idea, financing and infrastructure. The innovative aim of the project was to have various groups of people from different backgrounds working together in the same processes. The project team consisted of several artists and people with university educations, such as archaeologists, cultural geographers, biologists and geologists. The main objective of the project team was to provide the basis for the construction of a culturally inspired walking and bicycle path. Several rest spots/rest stops (“konstpauser”) designed with artistic cha­racter and influenced primarily by the municipality’s extensive nature/cul­tural heritage will be found along the path (which has been approved for construction). One initial task of the project team was to make an inventory of the nature and culture artifacts within the project area as a means of promoting na­ture/culture preservation for the benefit of future generations through information sharing. The walking/bicycle path will be accessible to all, with special provision for physically challenged individuals. The intention is to provide an environment for both quietude and physical recreation.

    The artists within the project embedded their artistic interpretations of the inventory and communicated them by suggesting artistic designs (sketches) related to the planned path. A jury then considered the sketches. Sketch, text, models and jury decisions (regarding the designs) are the objective of this research. The analysis of the material (sketches, texts, models and jury decisions, both oral and written) exposes the artistic processes. It is also the key to understanding the messages the artists intend to convey through their suggested designs. It is important to realize the significance (specific characteristics) of different types of sketches to be able to make decisions based on sketch materials. When sketches are examined, this awareness is central to making the right decision. In this study, three different types of sketches are examined, and the reading of each type is discussed.

    When studying the suggested designs, insight was gained regarding the differences between using computer-aided design and traditional sketch tools. Knowledge was also increased concerning the development of sketch techniques generally, and when using computers specifically. A dualism of sight and seeing in terms of the visualization of an idea exists, and it is discussed in the light of empirical examples. It is also placed in relation to important technological steps taken earlier in history. The use of Camera Obcura as a helpful tool for composition is one such step. The use of this tool impacted on how the inner view was changed and, with that, manners of expression as well. This is seen in the composition of paintings and the use of language. Our thinking is influenced by what we see, and that, in turn, influences our thoughts. In our contemporary western paradigm, our commonly-held definition of "seeing" is influenced by computer-gained visual representations and the processes used when producing them. The study confirms that while this particular type of sketch exposes the suggested design idea a bit clearer than traditional sketches, it also reveals errors in the suggested designs. I have also found that both written and spoken language routes the interpretation of sketch material. In terms of understanding how the suggested designs are chosen by a jury, this component (the spoken or written language) was seen in the empirical material revealed in this study. It was also theoretically confirmed.

    Together with an overall insight into the artistic processes, this study confirms the possibility of using artists in a development process. In this project, the process was to promote na­ture and culture preservation. It is valuable to integrate diverse areas of knowledge in the same process. This is true in both a social and an environmental sense. Finally, findings in this analysis confirm that artists are able to convey messages through their suggested designs (sketches). Those messages include interpretations of place, space, history and findings related to the project area.

  • 12.
    Johansson, Henrik
    Mälardalen University, School of Innovation, Design and Engineering.
    Evaluating Vivado High-Level Synthesis on OpenCV Functions for the Zynq-7000 FPGA2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    More complex and intricate Computer Vision algorithms combined with higher resolution image streams put bigger and bigger demands on processing power. CPU clock frequencies are now pushing the limits of possible speeds, and have instead started growing in number of cores. Most Computer Vision algorithms' performance respond well to parallel solutions. Dividing the algorithm over 4-8 CPU cores can give a good speed-up, but using chips with Programmable Logic (PL) such as FPGA's can give even more.

    An interesting recent addition to the FPGA family is a System on Chip (SoC) that combines a CPU and an FPGA in one chip, such as the Zynq-7000 series from Xilinx. This tight integration between the Programmable Logic and Processing System (PS) opens up for designs where C programs can use the programmable logic to accelerate selected parts of the algorithm, while still behaving like a C program.

    On that subject, Xilinx has introduced a new High-Level Synthesis Tool (HLST) called Vivado HLS, which has the power to accelerate C code by synthesizing it to Hardware Description Language (HDL) code. This potentially bridges two otherwise very separate worlds; the ever popular OpenCV library and FPGAs.

    This thesis will focus on evaluating Vivado HLS from Xilinx primarily with image processing in mind for potential use on GIMME-2; a system with a Zynq-7020 SoC and two high resolution image sensors, tailored for stereo vision.

  • 13.
    Julin, Fredrik
    Mälardalen University, School of Innovation, Design and Engineering.
    Vision based facial emotion detection using deep convolutional neural networks2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Emotion detection, also known as Facial expression recognition, is the art of mapping an emotion to some sort of input data taken from a human. This is a powerful tool to extract valuable information from individuals which can be used as data for many different purposes, ranging from medical conditions such as depression to customer feedback. To be able to solve the problem of facial expression recognition, smaller subtasks are required and all of them together form the complete system to the problem. Breaking down the bigger task at hand, one can think of these smaller subtasks in the form of a pipeline that implements the necessary steps for classification of some input to then give an output in the form of emotion. In recent time with the rise of the art of computer vision, images are often used as input for these systems and have shown great promise to assist in the task of facial expression recognition as the human face conveys the subjects emotional state and contain more information than other inputs, such as text or audio. Many of the current state-of-the-art systems utilize computer vision in combination with another rising field, namely AI, or more specifically deep learning. These proposed methods for deep learning are in many cases using a special form of neural network called convolutional neural network that specializes in extracting information from images. Then performing classification using the SoftMax function, acting as the last part before the output in the facial expression pipeline. This thesis work has explored these methods of utilizing convolutional neural networks to extract information from images and builds upon it by exploring a set of machine learning algorithms that replace the more commonly used SoftMax function as a classifier, in attempts to further increase not only the accuracy but also optimize the use of computational resources. The work also explores different techniques for the face detection subtask in the pipeline by comparing two approaches. One of these approaches is more frequently used in the state-of-the-art and is said to be more viable for possible real-time applications, namely the Viola-Jones algorithm. The other is a deep learning approach using a state-of-the-art convolutional neural network to perform the detection, in many cases speculated to be too computationally intense to run in real-time. By applying a state-of-the-art inspired new developed convolutional neural network together with the SoftMax classifier, the final performance did not reach state-of-the-art accuracy. However, the machine-learning classifiers used shows promise and bypass the SoftMax function in performance in several cases when given a massively smaller number of samples as training. Furthermore, the results given from implementing and testing a pure deep learning approach, using deep learning algorithms for both the detection and classification stages of the pipeline, shows that deep learning might outperform the classic Viola-Jones algorithm in terms of both detection rate and frames per second. 

  • 14.
    Karlsson, Jonas
    Mälardalen University, School of Innovation, Design and Engineering.
    FPGA-Accelerated Dehazing by Visible and Near-infrared Image Fusion2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Fog and haze can have a dramatic impact on vision systems for land and sea vehicles. The impact of such conditions on infrared images is not as severe as for standard images. By fusing images from two cameras, one ordinary and one near-infrared camera, a complete dehazing system with colour preservation can be achieved. Applying several different algorithms to an image set and evaluating the results, the most suitable image fusion algoritm has been identified. Using an FPGA, a programmable integrated circuit, a crucial part of the algorithm has been implemented. It is capable of producing processed images 30 times faster than a laptop computer. This implementation lays the foundation of a real-time dehazing system and provides a significant part of the full solution. The results show that such a system can be accomplished with an FPGA.

  • 15.
    Kiselev, Andrey
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    The Effect of Field of View on Social Interaction in Mobile Robotic Telepresence Systems2014In: Proceedings of the 9th ACM/IEEE International Conference on Human-Robot Interaction (HRI 2014), IEEE conference proceedings , 2014, p. 214-215Conference paper (Refereed)
    Abstract [en]

    One goal of mobile robotic telepresence for social interaction is to design robotic units that are easy to operate for novice users and promote good interaction between people. This paper presents an exploratory study on the effect of camera orientation and field of view on the interaction between a remote and local user. Our findings suggest that limiting the width of the field of view can lead to better interaction quality as it encourages remote users to orient the robot towards local users.

  • 16.
    Kiselev, Andrey
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Mosiello, Giovanni
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kristoffersson, Annica
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Semi-Autonomous Cooperative Driving for Mobile Robotic Telepresence Systems2014In: Proceedings of the 9th ACM/IEEE International Conference on Human-Robot Interaction (HRI 2014), IEEE conference proceedings , 2014, p. 104-104Conference paper (Refereed)
    Abstract [en]

    Mobile robotic telepresence (MRP) has been introduced to allow communication from remote locations. Modern MRP systems offer rich capabilities for human-human interactions. However, simply driving a telepresence robot can become a burden especially for novice users, leaving no room for interaction at all. In this video we introduce a project which aims to incorporate advanced robotic algorithms into manned telepresence robots in a natural way to allow human-robot cooperation for safe driving. It also shows a very first implementation of cooperative driving based on extracting a safe drivable area in real time using the image stream received from the robot.

  • 17.
    Leon, Miguel
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Xiong, Ning
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Molina, Daniel
    Univ Granada, DaSCI Andalusian Inst Data Sci & Computat Intelli, Granada, Spain..
    Herrera, Francisco
    Univ Granada, DaSCI Andalusian Inst Data Sci & Computat Intelli, Granada, Spain..
    A Novel Memetic Framework for Enhancing Differential Evolution Algorithms via Combination With Alopex Local Search2019In: International Journal of Computational Intelligence Systems, ISSN 1875-6891, E-ISSN 1875-6883, Vol. 12, no 2, p. 795-808Article in journal (Refereed)
    Abstract [en]

    Differential evolution (DE) represents a class of population-based optimization techniques that uses differences of vectors to search for optimal solutions in the search space. However, promising solutions/ regions are not adequately exploited by a traditional DE algorithm. Memetic computing has been popular in recent years to enhance the exploitation of global algorithms via incorporation of local search. This paper proposes a new memetic framework to enhance DE algorithms using Alopex Local Search (MFDEALS). The novelty of the proposed MFDEALS framework lies in that the behavior of exploitation (by Alopex local search) can be controlled based on the DE global exploration status (population diversity and search stage). Additionally, an adaptive parameter inside the Alopex local search enables smooth transition of its behavior from exploratory to exploitative during the search process. A study of the important components of MFDEALS shows that there is a synergy between them. MFDEALS has been integrated with both the canonical DE method and the adaptive DE algorithm L-SHADE, leading to the MDEALS and ML-SHADEALS algorithms, respectively. Both algorithms were tested on the benchmark functions from the IEEE CEC'2014 Conference. The experiment results show that Memetic Differential Evolution with Alopex Local Search (MDEALS) not only improves the original DE algorithm but also outperforms other memetic DE algorithms by obtaining better quality solutions. Further, the comparison between ML-SHADEALS and L-SHADE demonstrates that applying the MFDEALS framework with Alopex local search can significantly enhance the performance of L-SHADE. 

  • 18.
    Mishra, Chintan
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Khan, Zeeshan
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Development and Evaluation of a Kinect based Bin-Picking System2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 19.
    Pau, G.
    et al.
    Kore University of Enna, Italy.
    Bazzi, A.
    National Research Council, Italy.
    Campista, M. E. M.
    Universidade Federal do Rio de Janeiro, Brazil.
    Balador, Ali
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Towards 5G and beyond for the internet of UAVs, vehicles, smartphones, Sensors and Smart Objects2019In: Journal of Network and Computer Applications, ISSN 1084-8045, E-ISSN 1095-8592, Vol. 135, p. 108-109Article in journal (Refereed)
  • 20.
    Penner, Alexander
    Mälardalen University, School of Innovation, Design and Engineering.
    Measuring vibrations in video recordings by image analysis2014Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Gimbal mounted camera systems are used for capturing high quality, long-range video from inherently unstable mounts, such as helicopters. The rotational stability of such systems can be veried by mounting the system to a shake machine and using a laser-collimator to perform measurements. This process is, however, both intricate and time consuming, as well as susceptible to measuring errors. The purpose of this thesis, is to investigate the possibility to perform camera rotation measurements in video recordings, by means of image analysis, while maintaining an acceptable level of measurement accuracy.

    The method employed is an adaptation of existing target tracking techniques; using a mirror to record an adhesive circular marker attached to the front of the camera, in order to lter out any non-rotational marker movement. Three dierent algorithms for tracking the marker are evaluated; weighted centroid, dual conic ellipsis estimation and DFT registration. Evaluation is performed using a wide range of synthetic videos, simulating the primary error sources. Furthermore, the emergent problem of ltering out gyroscopic camera drift from the measurements is addressed. Finally, a software tool is presented that can be used for testing the rotational stability of the gimbal systems in a controlled environment.

  • 21.
    Ramberg, Andreas
    Mälardalen University, School of Innovation, Design and Engineering. 1992.
    Ocean Waves Estimation: An Artificial Intelligence Approach2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis aims to solve the mathematical inverse problem of characterizing sea waves based on the responses obtained from a marine vessel sailing under certain sea conditions. By researching this problem the thesis contributes to the marine industry by improving products that are using ocean behavior for controlling ship's dynamics. Knowledge about the current state of the sea, such as the wave frequency and height, is important for navigation, control, and for the safety of a vessel. This information can be retrieved from specialized weather reports. However, such information is not at all time possible to obtain during a voyage, and if so usually comes with a certain delay. Therefore this thesis seeks solutions that can estimate on-line the waves' state using methods in the field of Artificial Intelligence. The specific investigation methods are Transfer Functions augmented with Genetic Algorithm, Artificial Neural Networks and Case-Based Reasoning. These methods have been configured and validated using the n-fold cross validation method. All the methods have been tested with an actual implementation. The algorithms have been trained with data acquired from a marine simulation program developed in Simulink. The methods have also been trained and tested using monitored data acquired from an actual ship sailing on the Baltic Sea as well as wave data obtained from a buoy located nearby the vessel's route. The proposed methods have been compared with state-of-the art reports in order evaluate the novelty of the research and its potential applications in industry. The results in this thesis show that the proposed methods can in fact be used for solving the inverse problem. It was also found that among the investigated methods it is the Transfer Function augmented with Genetic Algorithm which yields best results. This Master Thesis is conducted under the Master of Engineering Program in Robotics at Mälardalens högskola in Västerås, Sweden. The thesis was proposed by Q-TAGG R&D AB in Västerås, Sweden, a company which specializes in marine vessel dynamics research.

  • 22.
    Åkesson, Ulrik
    Mälardalen University, School of Innovation, Design and Engineering.
    Design of a multi-camera system for object identification, localisation, and visual servoing2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this thesis, the development of a stereo camera system for an intelligent tool is presented. The task of the system is to identify and localise objects so that the tool can guide a robot. Different approaches to object detection have been implemented and evaluated and the systems ability to localise objects has been tested. The results show that the system can achieve a localisation accuracy below 5 mm.

1 - 22 of 22
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