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  • 201.
    Vasilev, Viacheslav
    University West, Department of Engineering Science.
    Automated masking of components: Case study in VBG Group Truck Equipment AB2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this Thesis is to investigate how to automate a process of masking details before painting. Masking is one of the most important phases in paint preparation and can be executed in various ways, depending mostly on type of product and on demands to parts which should be masked. This work addresses the certain process of masking lifting arms at VBG GroupTruck Equipment AB. This masking process basically represents a coupling of two parts together (lifting arm and rubber mask) and is simple to be executed manually. However,a large amount of repetitive work goes against ergonomics and effective utilization of human resources. Some of renowned benefits of automating process by means of robots are those considering, among others, elimination of monotonous work and process performance improvement. On the other hand, often it appears that operations which seem simple to execute by human become complicated for machines, and some level of human participation in a process still might be needed. Summing up, the solution for automating the masking of lifting arms should cut toa minimum (if not eliminate) all manual operations, and to be applicable for similar typeof work wherever possible.

  • 202.
    Venugopal Reddy, Dhanush
    University West, Department of Engineering Science, Division of Automation Systems.
    A Genetic algorithm with shuffle to solve the job shop scheduling problem2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Job shop scheduling problems are computationally complex combinatorial optimization problems. Genetic algorithms have been used in various forms and in combination with other algorithms to solve job shop scheduling problems. A partially flexible job shop with precedence constraints increases this complex behaviour. There are two main parts to optimizing a job shop, the routing and the scheduling. The objective here is to get consistent optimal makespan using a genetic algorithm. This paper firstly, presents a representation of the considered partially flexible job shop scheduling problem, which helps take into account the precedence constraints and reduce situations of deadlock. It starts with the genetic crossovers for routing and then a random shuffle technique is used for scheduling the problem. The computational results have shown that the algorithm performs well in terms of finding a consistent optimal schedule for the given problem.

  • 203.
    Vijayachandra, Manish Chandra
    University West, Department of Engineering Science.
    Optimizing Flow and Improving Robot Performance through Strategy: "Exploring Innovative Approaches to Enhance Industrial Automation Efficiency”2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    "Optimizing Flow and Improving Robot Performance through Strategy" is a specific goal that targets the improvement of the efficiency of the connecting rod manufacturing flow in Sansera Sweden AB plant. The production line has bottlenecks and manual inspection processes that caused delays and reduced productivity. To address these issues, the thesis proposed three solutions: implementing two automated torque wrenches in the assembly station, using a camera inspection system instead of manual inspection, and utilizing layout and robot motion optimization in the packing station.

    The results of the implemented solutions showed a significant reduction in cycle time. The use of two automated torque wrenches reduced the machining time by half of the actual time, resulting in a reduction of 14 seconds. Implementing the camera system reduced the manual inspection time by at least 10 seconds, and the use of layout and robot motion optimization reduced the cycle time by 2 to 3 seconds. On average, the total cycle time was reduced by 25 seconds. The simulation results showed the potential of these solutions to increase productivity and reduce delays in the conrod manufacturing flow. The findings of this thesis can be generalized to other manufacturing plants, and the proposed solutions can be used to improve productivity and efficiency. 

    The research analysis conducted for this thesis suggests that a centralized control is appropriate to implement, and the proposed solutions have the potential to increase productivity and reduce delays in the conrod manufacturing flow. The findings of this thesis can be generalized to other manufacturing plants, and the proposed solutions can be used to improve productivity and efficiency. 

    In conclusion, this thesis successfully addressed the bottlenecks and manual inspection issues in the conrod manufacturing flow by proposing and implementing effective solutions. The results showed a significant reduction in cycle time, which will lead to increased productivity and efficiency. The proposed solutions can be implemented in other manufacturing plants to address similar issues and improve overall productivity.

  • 204.
    Vijayan, Nivin
    University West, Department of Engineering Science.
    Designing and Implementing a Human-Machine Interface in Safe Plug and Produce Systems2023Independent thesis Advanced level (degree of Master (Two Years)), 20 HE creditsStudent thesis
    Abstract [en]

    This thesis introduces a Human-Machine Interface (HMI) developed to enhance safety and efficiency in Configurable Multiagent Systems (CMAS) operating in Plug-and-Produce robot cells. The HMI addresses challenges related to flexible CMAS configurations, specifically addressing collision detection difficulties. Through runtime Configuration and coding of CMAS, the HMI identifies safer robot paths to prevent collisions during real-world CMAS operations. The experimental phase involves a virtual environment, demonstrating the HMI's effectiveness in collision prevention during CMAS operations. This research represents a notable advancement in collision-free motion planning for flexible CMAS configurations, offering a valuable tool for operators to operate CMAS in dynamic production settings, fostering safer and more efficient robotic automation across industries

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  • 205.
    Vivo, Maria Vicenta
    University West, Department of Engineering Science, Division of Production Systems.
    Using Discrete Event Simulation as an Environment for a Reinforcement Learning Energy Optimizer2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Many of the planning and control problems can be modelled as sequential decision making processes. Reinforcement learning is considered as a reliable framework for solving such problems at the presence of uncertainties. In this regard, having an environment replicating the characteristics of the real system has been a major challenge. In this master thesis, the idea of employing a discrete event simulated model of a production cell in order to train a reinforcement learning scheduler is investigated. The focus is on energy optimization while meeting production rate as a demand. The thesis is conducted as part of a joint project be-tween University West, Chalmers University of Technology, and Volvo Group Trucks Op-erations.

  • 206.
    Wakim, Majed
    University West, Department of Engineering Science.
    Flexible Solution for an Automatic Assembly Cell2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This project is being carried out in collaboration with Parker Hannifin. The main objective of this project is to achieve a simulation of an automatic assembly cell for the assembly of the CRVs in the P70 hydraulic valve assembly line. The robotic cell uses the line layout to perform the assembly. It consists of a robot, an automatic feeder system, a conveyor system, an assembly table, and an aligner stand. The tool used to perform the assembly is a combination of two tools mounted on a multi-tool. The first tool is a vacuum gripper, and the second tool is a drill driver. The time taken by the robot to complete one assembly of a P70 module of three sections, with a size of six CRVs on each side, A and B, is eighty-eight seconds which is faster than the speed of a manual operator. The throughput rate of the assembly cell is forty-one complete assemblies per hour, which equals one hundred and twenty-three sections per hour. This result shows clear improvement comparing it to the manual assembly throughput rate. The minimum time for the automatic feeder system to request a refill is approximately twenty-two and a half minutes. A minimal change is required when a new specification is added to the assembly line. 

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  • 207.
    Wigerfelt, Jon
    University West, Department of Engineering Science.
    Vision system concept design for 3-D imaging: System integration in NDT thermographic tool for crack detection in welded components2023Independent thesis Advanced level (degree of Master (Two Years)), 20 HE creditsStudent thesis
    Abstract [en]

    Thermographic inspection has raised attention as a suitable Non Destructive Testing technique to detect cracks in welded components. In this work, complementary vision systems are designed to be implemented into an existing thermographic inspection tool, with the objective of improving the Probability Of Detection and general performance of the tool by detecting common welding features and defects. An analysis of the thermographic tool and a bibliographic review of contemporary 3-D vision systems deems the laser triangulation technique as the most suitable for the intended purpose. Thus, two drafts for incorporating laser triangulation systems in the thermographic tool are designed. In the first one, a laser line beam source is rotated to scan the surface, while in the second one the scanning is performed by a linearly displaced mirror with an static light source. Detailed schemes, design parameter equations and measurement triangulation equations are formulated for each method. With a justified selection of values for the design parameters, a theoretical achievable measurement accuracy of 12.5 µm and 0.14 mm can be obtained for the first and second designs, respectively. Considerations and possible real accuracies are indicated for each method. Finally, CAD models for each method are constructed following the design parameters and component dimensions. The models show that prototypes and real implementations of the designs are possible. As future work, prototypes and testing of the designs is suggested, to study the validity of the designs and implementation challenges. 

  • 208.
    Wu, Ronghua
    University West, Department of Engineering Science, Division of Automation Systems.
    Virtual Robotized NDT: Simulation in Robot Studio2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Human and machine cooperation has been developed for a long time to improve the productivity and because of advantages of the machine work, machine will play a more and more important role in the industrial production. To some extent, machine has already changed the world. This master thesis project was to use several robots build an automatic inspection line to inspect the wheel hub using the thermography with induction method. Three different methods are created in robot studio and the method with rotation tool was implemented as a demonstrator at PTC (production technology center).

    Compare the methods with each other and consider the limitations and productivity, the method with the rotation tool is the best choice for the company. The automation line includes several robots. In another words, the designed automation line can be considered to be several robot cells. Most sensors and calibration methods are set up due to the rules to build a robot cell. All signal analysis and processing are solved in the robot studio during the simulation process. Some needed robot cell components, equipment and different tools are used from the standard ABB robot studio library. Several special tools and equipment are designed and modelled in the NX and then converted to robot studio.

  • 209.
    Yazdizadehalborz, Hamidreza
    University West, Department of Engineering Science, Division of Production Systems.
    A Machine Learning Approach for PAPI Lights: Detection, Tracking, and classification2020Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Object detection and classification is an indispensable technology for interacting with the environment. In this way, the main problem is finding a robust algorithm to decrease time and computation. However, finding the object in all partsof the image, is time consuming with increment on computation and the probability of false detection. In addition, for fast moving agents, time and computational capacities on detection and classification are limited. The substitution one of the human's power with a machine, require to be mentioned that any ability of humans' uses prior knowledge to learn how can detect and classify the huge amount of information. For instance, although with new technology, machines reach the humans' visual capacity in accuracy and precision, finding the less computational and time-consuming algorithm would need more efforts by humans both in hardware and software.Utilising of deep learning, especially, Convolutional Neural Network (CNN) for automated object detection systems, has robust performance but required also high inference speed and memory. In the presented master thesis, an algorithm has been proposed that recognizes Path Precision Approach Indicator (PAPI) lights by image processing using camera geometry that uses the precise of aircraft and lights poses. The use of light position allows us to determine of a Region-Of-Interest (ROI) in an image to reduce the computational cost and false detection. In addition, by using the proper classic algorithm followed by deep learning precision of the prediction will be surveyed on class of lights. In this thesis valuation and selection of many algorithms based on the papers or experiments that have been considered on traffic lights detection and classification in autonomous vehicle driving.

  • 210.
    Yu, Huanyu
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    3D Scanning and Modeling with the use of a Mobile Robot2017Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In recent years, the number of mobile robot has increased rapidly. They can not only be used for carrying out tasks in hostile work environment, but also make people's daily life convenient. In the meantime, the rise of 3D technology has changed people's life with its applications in the fields of industrial life and daily life. Therefore, the combination of 3D technology and mobile robot has enormous potentials.

    The objective of this project is to create a model of an object or indoor environment with the help of a mobile robot. A 3D scanner which can be attached on a mobile robot will be used for scanning. With the depth information collected, the point clouds can be gotten. The basic way of reconstructing the model is called Kinect Fusion, it uses Kinect camera to scan the area and creates a model with help of Iterative Closest Point algorithm and Truncated signed distance function which will be introduced in section 2.5. The registration of the point clouds and the localization of the camera can be realized by using ICP algorithm. The software which is used to implement these methods is Visual Studio 2012 with OpenCV and KinectFusion library.

    As the camera should be able to be used on any kind of robot, the aim of these tests is to find a better way to get a high quality model of the area. In this paper, two main experiments have been done. One of them is about scanning a target object from different distances. There will be errors between object actual size and its model size. And the relationship between the errors and the distances will be found out. The other one is focused on the movement of the camera. There are two scenarios in this experiment. The first one is to move the camera with different speed and the other scenario is to scan an object by moving the camera around the object. The result shows that the robot attached with the camera should move slowly so that the camera can capture enough frame images for the model. And keep scanning one object by moving the camera around it can't make the model looks better but worse.

  • 211.
    Yu, Liang
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Automatic obstacles avoidance pickup and placement path generation achievement with scanning of environment for an industrial robot2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Industrial robots are widely used in modern industry fields because of the development of robot technology. In robot palletizing or bin-picking application, robot needs to automatically generate path for achieving robot picking and placing operation even if there exist obstacles. This project is to design and test a robot system that can move without collisions in a changeable environment. And communication is realized between two computers through an industrial communication protocol.

    ROS has been chosen as a simulation platform for the robot path planning simulation as it has some independent advantages, like open-source, supporting multiple programming languages, integrating a lot of open source tools and advanced algorithms. ROS MoveIt! software is used for motion planning, operation control, 3D perception, kinematic solution, collision detection, and so on. Through RRT method, robot path planning is achieved and through Flexible Collision Library, collision detection is achieved. For robot system test experiments and results, taking ABB IRB 2600 robot as a test industrial robot, a robot simulation system in ROS is designed and set up to realize obstacles free picking and placing path planning task of the robot.

    Firstly, for obtaining external obstacles information, Kinect V1 camera is used and calibrated for eliminating distortion and obtains colour image and depth image. Secondly, by using Point Cloud Library, the images are transformed to point cloud images with filtering for eliminating noise. Thirdly, by using OctoMap library, the scene including obstacles are created to 3D occupancy map. Furtherly, according to the map, robot obstacles avoidance pickup and placement operation is achieved in ROS.

    Finally, for testing and evaluating the system, the robot model, a pickup object and an obstacle model are created in ABB RobotStudio software which is the same as ROS's and further achieves co-simulation motion in ROS and ABB RobotStudio by ROS TCP/IP socket program. By running path planning in ROS, the robot achieves obstacle avoidance path planning and pickup and placement operation in ABB RobotStudio.

  • 212.
    Zakeriharandi, Mohammadali
    University West, Department of Engineering Science, Division of Production Systems.
    Energy optimal scheduling by reinforcement learning2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    While scheduling is extensively studied by operations research and heuristic methods, both paradigms face challenges to include uncertainties into the problem and to be used on a realtime basis. Reinforcement learning is a well-documented approach for solving various planning and control problems. In this thesis, application of reinforcement learning for production scheduling is studied. Inverse scheduling is defined as the problem of finding the number of jobs and duration times to meet an input capacity demand. A reinforcement learning framework is proposed for solving inverse scheduling while optimizing energy consumption. Discrete event simulation is used to model the environment while involving uncertainties. Due to the inherent characteristics of the problem in hand, deep neural networks are applied for approximating the policy. The trained agent can be used both for scheduling (production planning) and rescheduling (production control). A production cell is studied as a testbed, and using the trained agent, a six percent reduction in the energy level is observed in simulation following a proposed energy signature. Strengths and weaknesses of the suggested framework are presented, and essential features identifying its success are discussed. To generalize the approach to large scale problems, further modifications are needed both at the side of modelling and implementation. The thesis is conducted as part of a joint project between University West, Chalmers University of Technology, and Volvo Group Trucks Operations, named SmoothIT.

  • 213.
    Zhang, Cheng
    University West, Department of Engineering Science, Division of Automation Systems.
    Influence of surface roughness on thermography measurement2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This university Bachelor's Thesis was performed to explore the influence of surface roughness on the thermography measurement.

    Thermography is a non-destructive testing method which can be used to detect cracks. However, it is hard to define how the surface roughness influences the emissivity and the result of a thermography measurement, as well as how the angle of the excitation source influences the result. Therefore, this work aims to define how the heating angle and surface roughness influence the thermography measurement, define the relationship between surface roughness and emissivity for the same crack, and define the influence of the angles which composed of the heating source, the direction of crack and the direction of surface roughness on thermography measurement.

    In this report, the theories of radiation and Signal-to-noise ratio (SNR) were explained, clearly. Also, two kinds of experiments were set up. One is focus on how the heating angle influence the thermography measurement, the other is focus on how the angle of the heating source, in relation to the crack direction and the direction of surface roughness, influence the SNR value.

    The conclusions of these experiments are that the heating of a crack increases as the angle decreases (from wide side to narrow side) and the angle ofincreases (from horizontal to vertical). Moreover, the SNR value decreases as the surface roughness increases. For the same surface roughness, the SNR value increases with increased crack angle (0°, 45° or 90°) and with decreased sample position angle (horizontal, 45°or vertical). What is more, the higher surface roughness, the larger the influence of the crack angle and the sample position angle. Finally, when the surface is polish, the crack angle and the sample position angle does not have any influence.

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  • 214.
    Zhang, Ye
    University West, Department of Engineering Science, Division of Automation Systems.
    Simulation of a production line in Robot Studio: Modelling and simulation2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    With the development of science and technology, production system in modern factories is more complex than it used to be. In order to cut unnecessary loss and protect operators from failure, simulation plays an essential role on testing production lines. In this thesis work, the model of production lines, located in Production Technology Centre (PTC) of University West were built with NX, Autodesk Inventor and simulated with Robot studio. And the production line includes three robot cells (milling machine work cell, turning machine work cell and conveyance work cell, respectively), a gantry robot and some auxiliary equipment, i.e. tables, computers, human task console. Signals were added to make sure the model could work as reality.

    Different measurement methods were used in order to locate production line components at right positions due to their importance to the accuracy of simulation. Measurement methods were also compared with each other to show the error. For instance, the error of CAD models, measurement, and the distance error among equipment, etc.

  • 215.
    Öztürk, Mehmet Cihan
    University West, Department of Engineering Science, Division of Production Systems.
    Virtual Commissioning: A Tool for Control System Validation2021Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The on-site commissioning is a vital milestone for the project lifecycle of a manufacturing system. This process also plays a crucial role in the future financial accomplishment of the manufacturing system. From the point of view of control systems associated with the manufacturing system, the most common problems encountered during the commissioning process are related to the software. However, early detection of these software-related problems is possible by enabling virtual commissioning technology.

    The control system of the manufacturing system investigated within the scope of this thesis is developed by Midroc Automation AB. In the thesis, simulation and simulation model creation approaches, further benefits of the simulation model along the life cycle of the manufacturing system and PLC code validation possibilities with virtual commissioning are analysed by considering qualitative and quantitative advantages of virtual commissioning. The work is performed using SIMIT for the development of the virtual plant model, PLC-SIM Advanced for simulation of PLC controller and TIA Portal for validation of the control system.

    The experiment attempts to develop a virtual commissioning environment by applying the model-based virtual commissioning approach. Furthermore, software in the loop configuration is used to simulate the real PLC controller. This attempts demonstrates whether it is possible to validate the control system. The results are that the validation of the control system is possible considering the objectives, technical and commercial limits of the automation project. Ultimately, efficient use of time-saving tools in the preparation of the necessary environment for virtual commissioning is provided.

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