Browsing by Department "Automaatio- ja systeemitekniikan laitos"
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- A-Stack : a TDMA framework for reliable, real-time and high data-rate wireless sensor networks
School of Electrical Engineering | D4 Julkaistu kehittämis- tai tutkimusraportti tai -selvitys(2012) Cosar, Emre Ilke; Mahmood, Aamir; Björkbom, Mikael (editor)The reduced size, power consumption and cost of wireless sensors make them an excitingtechnology for many monitoring and control applications. However, developing reliable, realtimeand high data-rate applications is challenging due to time-variations and interference inwireless channels and the medium access delays. For high data-rate and real-time applications,time division multiple access (TDMA) based medium access approach performs better ascompared to carrier sense multiple access (CSMA) based approach. On the other hand,implementation of TDMA in resource constrained wireless nodes requires difficult designdecisions. This document presents A-Stack, a real-time protocol stack for time synchronized, multichanneland slotted communication in multi-hop wireless networks. The stack is developed tomeet the reliability and accuracy requirements of real-time applications such as wirelessautomation and wireless structural health monitoring. A-Stack provides a flexible developmentenvironment for such applications by ensuring deterministic reliability and latency. It includesMAC, routing and time-synchronization protocols as well as a node-joining algorithm. Thestack is further supplemented with PC tools for optimizing the network as per the targetapplication for easy prototyping. This document explains the design and operational aspects ofA-Stack. Various deployment scenarios as well as long term system and communicationreliability tests are presented in the document. - ActionPool : a novel dynamic task scheduling method for service robots
Aalto-yliopiston teknillinen korkeakoulu | Doctoral dissertation (monograph)(2010) Taipalus, TapioService robots require the seamless utlisation of several technical disciplines. Most of the required technologies are sufficiently advanced to provide feasible solutions to be used in the designing of service robots. For instance, mechanical engineering, control theory, electronics and electrical engineering aspects of the design have all matured well. On the other hand, it is the perception and artificial intelligence that provide the means for modelling the environment and the knowledge which are lagging behind. The latter two disciples in their current state, greatly limit the complexity of the tasks which can be performed by service robots. In this thesis, an ActionPool method for representing task knowledge and executing multiple tasks simultaneously with service robots is presented. The method is based on a concept in which the actions that are ready for execution are placed into a pool and from those most suitable for the situation are selected one by one. The number of actions in a pool and the number of tasks are limited only by the available computational resources. The actions can belong to different tasks, and thus the action pool allows the robot's indivisible resource to be dynamically dealt out for various tasks requiring the resources. In the ActionPool method, the functional parts of the service robot are divided into resources and an action pool is assigned to each one of them. This way, numerous tasks can be executed simultaneously. The ActionPool method allows a natural way of dynamically adding and removing tasks to and from the robot's active execution. The action selection method can direct the perception processes to observe the relevant parts of the environment. The ActionPool method has been implemented on two different service robot platforms to verify the generic nature of the method. Several tasks have been executed successfully to validate the claims about the qualities of the method. Compared to previous approaches, this work provides a fresh execution- and contingency-centric vantage point to the well studied robot control problem. - Active control of radial rotor vibrations in electric machines : identification, modeling and control design
Faculty of Electronics, Communications and Automation | A4 Artikkeli konferenssijulkaisussa(2008) Orivuori, Juha; Laiho, Antti; Sinervo, AnssiThis paper presents results related to modeling, identification, control design and simulation of an electric motor equipped with a new force actuator. The model consists of several partial models, thus separating certain physical phenomena into independent processes. The inputs and outputs of the models to be identified are strongly correlated. This makes the identification process significantly more complicated. Three different control algorithms are designed for the process. The performance of the control algorithms are tested against finite element models in extensive simulations. The paper concludes in description of preliminary test results with an actual test machine. - Adaptive wastegate control of combustion engines
School of Electrical Engineering | Master's thesis(2013) Aalto-Setälä, JoonasIn this thesis the implementation of adaptive control methods for internal combustion engine waste gate control is investigated. The main targets are the marine internal combustion engines and the aim is to improve engine efficiency, reduce emissions and simplify the engine calibration process. First the mean value models for an internal combustion engine air path and engine dynamics are presented. The air path model is linearized, scaled and its order is reduced. In addition to a normal PID-controller adaptive control methods are presented. These include internal model control; feed forward those changes as a function of engine load and model reference adaptive control. The chosen control methods are implemented for the linearized and the nonlinear model and simulated with Simulink. Finally the performance of the control methods are analyzed and compared. - Advanced process monitoring and control methods in mineral processing applications
School of Electrical Engineering | Doctoral dissertation (article-based)(2012) Remes, AnttiIn minerals processing the high material volumes yield the fact that benefits of even small improvements in the process efficiency are remarkable. On a daily basis, the efficiency of a concentrating plant relies on the performance of the process control system, and secondly, on the adequate information of the process state provided for the plant operators. This thesis addresses the problems in the monitoring and control of the selected, widely applied mineral concentration unit processes and the processing circuits. The case studies cover operations in the ore grinding stages, including size separation units, followed subsequently by the concentration and the thickening stages in the downstream process. The developed methods and applications are all verified with industrial data, industrially identified models or by the practical implementations and tests on the industrial case plants. Advanced control systems - including a rule-based, a fuzzy and a model predictive control, with different combinations and setups - are studied with simulated grinding and flotation processes. A new model-based expert system for controlling of the ground ore particle size and the circulating load of the grinding process is proposed. The system was tested with a simulation model representing an industrial milling of apatite ore. In a plant-wide process monitoring, a data-based modeling approach is applied to predict the concentrate quality and the impact of the grinding stage parameters on that. The plant model, used for the monitoring, is updated adaptively; this enables timely information on the process. The monitoring system was set up based on the data of a chromite ore processing plant. Two unit operations, a hindered settling separator and a thickener, were modeled from a viewpoint of equipment monitoring and control purposes. The hindered settling separator incorporates both a mechanistic particle-settling model and a separation efficiency characterization curve in a novel manner. Separation characteristics in a pyrite concentrate case and in a ground apatite ore case were studied with the model. Operation of a thickener was modeled based on on-line mass-balance estimation. The monitoring application was implemented in an industrial apatite concentrate thickener. This thesis demonstrates the benefits of the above described monitoring and control methods. The metallurgical performance improvements are pointed out for each case. Also this thesis outlines the practical implementation and robustness issues for the methods. Thus the thesis promotes the advantages of more extensive use of plant models in process operation purposes. - Affordance-based task communication methods for astronaut-robot cooperation
Sähkötekniikan korkeakoulu | Doctoral dissertation (monograph)(2011) Heikkilä, Seppo SThe problem with current human-robot task communication is that robots cannot understand complex human speech utterances, while humans cannot efficiently use the fixed task request utterances required by robots. Nonetheless, future planetary exploration missions are expected to require astronauts on extra-vehicular activities to communicate task requests to robot assistants with speech- and gesture-type user interfaces that can be easily embedded in their space suits. The solution proposed in this thesis is indirect task communication based on the human-like ability to utilise object-action relationships in task communication. Conventional task communication methods, in which all task parameters need to be communicated explicitly, are evaluated against task communication methods where affordances, i.e. action possibilities, are used to complete task communication. These so-called affordance-based task communication methods are evaluated by means of four user experiments: two performed with a fully autonomous centauroid robot in a planetary exploration work context and two with a simulated robot in a lander assembly work context. The first two experiments are performed in unambiguous work environments, where each object is associated with only one action and vice versa, while the last two experiments are performed in ambiguous work environments, where each object and action is normally associated with several actions and objects, respectively. The user experiments show that affordance-based task communication methods can be used to decrease both the human workload and task communication times in a planetary exploration work context. Furthermore, affordance-based task communication methods are found to be preferred over conventional task communication methods. The affordance-based task communication methods derived can be applied to facilitate any human-robot task communication that includes a priori known or recurring task sequences. In this thesis, the feasibility of the approach was demonstrated for frame-based dialogue managers, which are widely used in robotics. - Analysis and planning of industrial software rollout project
School of Electrical Engineering | Master's thesis(2012) Saarinen, Lauri - Venttiilivalmistuksen tuotantokonseptin analyysi ja kokoonpanoa palvelevan keräilyvaraston suunnittelu
School of Electrical Engineering | Master's thesis(2011) Penttilä, Ilkka KaarloThe objective of this Master's Thesis was to analyze and design a new inventory management concept for customer-driven assembly of industrial valves. The work was related to the implementation of a new valve production facility. The work covered analysis of the company's production concept and the status of existing production. The essential production philosophies were covered in terms of current versus desired process design. The new inventory concept was designed to best meet the demands set from production and assembly. The key methods in the work were measuring material flows, layout design and analysis of inventory item data. The key areas of the literature review in this Master's Thesis were manufacturing planning and control, lean production and supply chain management, forming the theoretical background for the new production concept. The framework to analyze the production concept consisted of market requirements and demand management, production task, manufacturing process design, and manufacturing planning and control system design. Logistics requirements were analyzed in the supply chain management and inventory management parts of the thesis. Measuring material flows highlighted the external inputs and outputs of the inventory and the consequent requirements. Internal demands for the inventory included the efficiency and capacity of the basic warehouse operations as part of a lean manufacturing unit. The analysis of inventory item data was essential to decisions about inventory management principles. The main result of this Master's Thesis was a model of the inventory management concept, taken into use in the new production plant. The inventory concept is introduced through layout drawings and operating principles in the key functions. The results are analyzed in terms of production volume demands, visual control and safety. Also, the functionality of the new concept is evaluated, for example safety and security. The first implementation results are encouraging: the new concept seems to achieve the targets set for it, both in quantitative and qualitative terms. - Analytical production reporting in the process industries
Helsinki University of Technology | Master's thesis(2008) Toiviainen, PaavoTämä diplomityö käsittää tutkimuksen ja ratkaisuehdotuksen koskien geneeristä tietovaraston tietomallia tuotannon raportointiin prosessiteollisuudessa. Aloite tutkimukseen syntyi työn tilaajana toimineen yhtiön tarpeesta laajentaa nykyisen tietovarastotuotteen markkinoita suuremmalle prosessiteollisuuden alueelle. Tutkimuksen tavoitteena oli suunnitella ja toteuttaa geneerinen tietomalli käyttämällä ISA-95 standardia pohjana tietorakenteen suunnittelussa. Standardinmukaisuuden ja geneerisyyden avulla tavoitellut hyödyt ovat tietovaraston implementointiprosessin harmonisoiminen, yhteensopivuuden varmistaminen eri prosessiteollisuuden alojen tiedontarpeiden ja järjestelmien kanssa sekä standardien tietotyyppien ja rajapinnan tarjoaminen muille tietojärjestelmille. Aihetta tutkittiin toteuttamalla kattava kirjallisuuskatsaus koskien tietovarastoteoriaa, ISA-95 standardia ja sen sovelluksia sekä liiketoimintatiedon hallintaa erityisesti tiedon käyttäjän näkökulmasta. Tietovaraston vaatimusten määrittely, suunnittelu- ja toteutusprosessi sekä toteutetun mallin kuvaus esitetään diplomityön tapaustutkimusosiossa. Tietomalli toteutettiin käyttäen dimensiomallintamista, mikä on laajalti käytetty menetelmä tietovaraston rakentamiseen. Tietomallin raportoinnin suorituskyky, kyselyiden tehokkuus ja yleinen toimivuus evaluoitiin testitapauksien avulla. Testit käsittelivät tuotantoraportoinnin tiedontarpeiden täyttämistä ja analyyttisten tilapäisraporttien sekä porautuvien raporttien luomista. Lopputuloksena toteutettu tietomalli on yhteensopiva ISA-95 standardin tietomallin kanssa ja noudattaa dimensiomallinnuksen hyviksi todettuja mallinnusmenetelmiä. Tiedonhankintaprosessin sujuvuus, kyselyiden tehokkuus ja tiedontarpeisiin vastaaminen täyttävät nykyaikaiselle tietovarastolle asetetut vaatimukset. - Application integration in Oracle-based SaaS environments
School of Electrical Engineering | Master's thesis(2012) Riuttamäki, Martti - Application-driven data processing in wireless sensor networks
Sähkötekniikan korkeakoulu | Doctoral dissertation (article-based)(2011) Bocca, MaurizioWireless sensor networks (WSNs) are composed of spatially distributed, low-cost, low-power, resource-constrained devices using sensors and actuators to cooperatively monitor and operate into the environment. These systems are being used in a wide range of applications. The design and implementation of an effective WSN requires dealing with several challenges involving multiple disciplines, such as wireless communications and networking, software engineering, embedded systems and signal processing. Besides, the technical solutions found to these issues are closely interconnected and determine the capability of the system to successfully fulfill the requirements posed by each application domain. The large and heterogeneous amount of data collected in a WSN need to be efficiently processed in order to improve the end-user comprehension and control of the observed phenomena. The thesis focuses on a) the development of centralized and distributed data processing methods optimized for the requirements and characteristics of the considered application domains, and b) the design and implementation of suitable system architectures and protocols with respect to critical application-specific parameters. The thesis comprehends a summary and nine publications, equally divided over three different application domains, i.e. wireless automation, structural health monitoring (SHM) and indoor situation awareness (InSitA). In the first one, a wireless joystick control system for human adaptive mechatronics is developed. Also, the effect of packet losses on the performance of a wireless control system is analyzed and validated with an unstable process. A remotely reconfigurable, time synchronized wireless system for SHM enables a precise estimation of the modal properties of the monitored structure. Furthermore, structural damages are detected and localized through a distributed data processing method based on the Goertzel algorithm. In the context of InSitA, the short-time, low quality acoustic signals collected by the nodes composing the network are processed in order to estimate the number of people located in the monitored indoor environment. In a second phase, text- and language-independent speaker identification is performed. Finally, device-free localization and tracking of the movements of people inside the monitored indoor environment is achieved by means of distributed processing of the radio signal strength indicator (RSSI) signals. The results presented in the thesis demonstrate the adaptability of WSNs to different application domains and the importance of an optimal co-design of the system architecture and data processing methods. - Applying agent technology to constructing flexible monitoring systems in process automation
Doctoral dissertation (monograph)(2008) Pirttioja, TeppoThe dissertation studies the application of agent technology to process automation monitoring and other domain specific functions. Motivation for the research work derives from the development of industrial production and process automation, and thereby the work load of operating personnel in charge of these large-scale processes has become more complex and difficult to handle. At the same time, the information technology infrastructure in process automation domain has developed ready to accept and utilise novel software engineering solutions. Agent technology is a new programming paradigm which has attractive properties like autonomy, flexibility and a possibility to distribute functions. In addition, agent technology offers a systematic methodology for designing goal based operations. This enables parts of the monitoring tasks to be delegated to the system. In this research, new agent system architecture is introduced. The architecture specifies a structure that enables the use of agents in the process monitoring domain. In addition, an introductory internal layered design of an agent aiming to combine Semantic Web and agent technologies is presented. The developed agent architecture is used in conjunction with the systematic agent design methodology to construct and implement four test cases. Each case has industrially motivated interest and illustrates various aspects of monitoring functionalities. These tests provide evidence that by utilising agent technology it is possible to develop new monitoring features for process operators, otherwise infeasible as such within current process automation systems. As a result of the research work, it can be stated that agent technology is a suited methodology to realise monitoring functionalities in process automation. It is also shown, that by applying solutions gained from the agent technology research, it is possible to define an architecture that enables to utilise the properties offered by agents in process automation environment. The proposed agent architecture supports features that are of generic interest in monitoring tasks. The developed architecture and research findings provide ground to import novel software engineering solutions to process automation monitoring. - Konenäön soveltaminen lasiesineiden laadunvalvonnassa
School of Electrical Engineering | Master's thesis(2011) Tuominen, Sampo - Reitinsuunnittelumenetelmien soveltaminen siltanostureissa
School of Electrical Engineering | Master's thesis(2012) Mäki, ViljamiPath planning is a common problem and one of the most essential research topics in robotics. More and more path optimization is required in industrial and domestic applications ranging from automated forklifts to cleaning robots and IT networks. Most used methods are based on solutions invented in 1960's and the basic principles have stayed the same for decades. Still the complexity of applications has forced researchers to develop more efficient variations of these methods. This thesis reviews some of the most common methods and studies their suitability for bridge crane applications. The aim is to find a solution to replace manually created routes with an automated path planning in a known work space and to apply it to most common bridge crane types. Reliability and easy implementation with reduced workload and smaller risk for errors compared to current methods are main criteria for the solution. One central problem in crane application is the scarce resources offered by the technology normally used in cranes. Many of the current programmable logic controllers are very constrained with regards to memory usage. Memory usage in general is a common stumbling block in path planning methods. For this reason suitability of other options, besides programmable logic controller, are also studied. This thesis presents a solution that fulfils functional criteria and allows automated path planning and path following in most common bridge crane types. Path planning is done with a slightly modified A * algorithm together with post-processing to make the plan suitable for crane application. In addition, two simple methods for path following are studied and a software tool is created to allow designing of crane's working area. - Artificial neural network approach to mobile robot localization
School of Electrical Engineering | Master's thesis(2012) Swords, DavidIn the robotics community, localization is considered a solved problem; however, the topic is still open to investigation. Mobile robot localization has been focused on developing low-cost approaches and there has been great success using probabilistic methods. Parallel to this, and to a much lesser extent, artificial neural networks (ANNs) have been applied to the problem area with varying success. A system is proposed in this thesis where the typical probabilistic approach is replaced with one based purely on ANNs. This type of localization attempts to harness the simplicity, scalability and adaptability that ANNs are known for. The ANN approach allows for the encapsulation of a number of steps and elements well known in a probabilistic approach, resulting in the elimination of an internal explicit map, providing pose estimate on network output and network update at runtime. First, a coordinate-based approach to localization is explored: 1D and 2D trained maps with pose estimates. Second, the coordinate-based approach is eliminated in an effort to replicate a more biologically inspired localization. Finally, a path-finding algorithm applying the new localization approach is presented. - Jätevedenpuhdistamon on-line analysaattorien autokalibrointi
School of Electrical Engineering | Master's thesis(2011) Jokelainen, Miikka - Automated control of compliance with production standards in precision agriculture
School of Electrical Engineering | Doctoral dissertation (article-based)(2013) Nikkilä, RaimoSignificant manual effort is currently involved in monitoring the compliance of agricultural production with legislation. While this administrative effort has little actual benefit for farms, compliance with legislation, or more generally production standards, is tied to the payout of economically vital farm subsidies. Information technology, together with the data collected automatically in precision agriculture, could alleviate this problem by automatically determining compliance with a significant portion of agricultural production standards. This thesis identifies the technical requirements of automated compliance control, formulates a design that conforms with the requirements of the stakeholders in precision agriculture and evaluates this design. The primary research objective can be further subdivided into three information systems: a farm management information system (FMIS) for precision agriculture, an infrastructure of Web services for automated compliance control and finally, spatial computer inference. These research objectives are addressed with the methodology of design science, using the agricultural field operation of precise fertilisation as the principal use case for automated compliance control. The results consist of information system designs and evaluation of these designs for functionality and feasibility. This thesis contributes the designs for three information systems: a software architecture for an FMIS in precision agriculture, a service infrastructure for automated compliance control and spatial computer inference with an interchangeable rule format. Through their prototype implementations, these are evaluated to constitute the necessary framework for automated compliance control. While technically demanding, automated compliance control with pertinent agricultural legislation is attainable, given the functionality of precision agriculture and the information systems presented in this thesis. However, the feasibility of the process relies on a degree of data interchange, which due to the lack of established data formats is currently difficult in agriculture. On the other hand, parts of the proposed solution can be applicable on a shorter time frame in agriculture or other domains. - Automated measurements and pH control of microalgae cultivation
School of Electrical Engineering | Master's thesis(2012) Nenonen, SusannaMicro-algae are a diverse group of photosynthetic unicellular microorganisms. Microalgae grow fast and under certain conditions half of their dry weight can be lipids. For this reason, micro-algae are currently regarded as the most promising biofuel feedstock. Large scale commercial microalgae cultivation is carried out in artificial open ponds or closed photo bioreactors. With photo bioreactors high productivities can be achieved, but the cultivation techniques require further development. It is also necessary to determine the optimal growth conditions and how the lipid content can be maximized. Maintaining optimal conditions requires several variables to be continuously monitored and also controlled when needed. This work presents a system created to automate the measurements of environmental variables and pH control of microalgae cultivation. It links instruments from different vendors into one integrated system, allowing the measurement data to be stored in one common file. In addition pH is maintained at the desired set point value. The system is used as a research platform for pilot-scale cultivation of microalgae. The system was tested in practice in an experimental cultivation of diatom Phaeodactylum Tricornutum. The results indicate that the system is suitable for reliable automation of the measurements and pH control of pilot scale microalgae cultivation. - Automaattitestaus taajuusmuuttajan ohjelmistokehitysprosessin osana
School of Electrical Engineering | Master's thesis(2011) Kankaanranta, LasseThe objective of this thesis was further development of automated testing as part of a new inverter software development process. Different software processes were studied including traditional methods as well as agile methods. The theory of software testing was examined to the extent needed for this thesis. Automated testing theory and empirical research were studied to obtain sufficient understanding of the nature of automated testing. The case of this thesis was one of the current software development projects of ABB Oy Drives. This project is part of a large scale development effort with multiple software and hardware projects. The establishment of automated testing in this project was evaluated against automated testing theory. The case was not only a research topic for this thesis. Automated testing in this project was constantly improved during the thesis. The project features also an agile practice called continuous integration that works best when combined to automated testing during development. A small Smoke test set was developed as a concrete improvement for the automated testing effort. The objective is to confirm, that no basic functionality has been broken with the last commit to version control. This enables following the continuous integration principle "Keep it green". Additionally the configuration management of automated testing in the project was taken to a better level. A smart version control system as well as continuous integration server was introduced to the project and most importantly the cooperation between team members and development teams was improved. - Turvalattian moduulien automaattinen testausjärjestelmä valmistuksen yhteydessä
School of Electrical Engineering | Master's thesis(2011) Sydänmaanlakka, Ville