8 research outputs found

    Formal Digital Description of Production Equipment Modules for supporting System Design and Deployment

    Get PDF
    The requirements for production systems are moving towards higher flexibility, adaptability and reactivity. Increasing volatility in global and local economies, shorter product life cycles and the ever-increasing number of product variants arising from product customization have led to a demand for production systems which can respond more rapidly to these changing requirements. Therefore, whenever a new product, or product variant, enters production, the production system designer must be able to create an easily-reconfigurable production system which not only meets the User Requirements (UR) but is quick and cost-efficient to set up. Modern production systems must be able to integrate new product variants with minimum effort. In the event of a product changeover or an unforeseen incident, such as the mechanical failure of a production resource, it must be possible to reconfigure the production system smoothly and seamlessly by adding, removing or altering the resources. Ideally, auto-configuration should obviate the need to manually re-programme the system once it has been reconfigured.The cornerstone of any solution to the above-mentioned challenges is the concept of being able to create formalised, comprehensive descriptions of all production resources. Providing universally-recognised digital representations of all the multifarious resources used in a production system would enable a standardised exchange of information between the different actors involved in building a new production system. Such freely available and machine-readable information could also be utilised by the wide variety of software tools that come into play during the different life cycle phases of a production system, thus considerably extending its useful life. These digital descriptions would also offer a multi-faceted foundation for the reconfiguration of production systems. The production paradigms presented here would support state-of-the-art production systems, such as Reconfigurable Manufacturing Systems (RMSs), Holonic Manufacturing Systems (HMSs) and Evolvable Production Systems (EPSs).The methodological framework for this research is Design Research Methodology (DRM) supported with Systems Engineering, Action Research, and case-based research. The first two were used to develop the concept and data models for the resource descriptions, through a process of iterative development. The case-based research was used for verification, through the modelling and analysis of two separate production systems used in this research. The concept, on which this thesis is based, is itself based on the triplicity of production system design, i.e. Product, Process and Resource. The processes, are implemented through the capabilities of the resources, which are thus directly linked to the product requirements. The driving force behind this new approach to production system design is its strong emphasis on making production systems that can be reconfigured easily. Successful system reconfiguration can only be achieved, however, if all the required production resources can be quickly and easily compared to all the available production resources in one unified, and universally accepted form. These descriptions must not only be able to capture all of a production system’s capabilities, but must also include information about its interfaces, kinematics, technical properties and its control and communication abilities.The answer to this lies in the Emplacement Concept, which is described and developed in this thesis. The Emplacement Concept proposes the creation of a multi-layered Generic Model containing information about production resources in three different layers. These are the Abstract Module Description (AMD), the Module Description (MD), and the Module Instance Description (MID). Each of these layers has unique characteristics which can be utilised in the different phases of designing, commissioning and reconfiguring a production system. The AMD is the most abstract (general) descriptive layer and can be used for initial system design iterations. It ensures that the proposed resources for the production system are exchangeable and interchangeable, and thus guides the selection of production resources and the implementation (or reconfiguration) of a production system. The MD is the next level down, and provides a more detailed description of the type of production resource, providing ’finer granularity’ for the descriptions. The MID provides the finest level of granularity and contains invaluable information about the individual instances of a particular production resource. This research involves two practical implementations of the Generic Model. These are used to model and digitally represent all the production resources used in the two use-case environments. All the modules in the production systems (25 in all) were modelled and described with the data models developed here. In fact, we were able to freeze the data models after the first case study, as they didn’t need any major changes in order to model the production resources of the second use-case environment. This demonstrates the general applicability of the proposed approach for modelling modular production resources.The advantages of being able to describe production resources in a unified digital form are many and varied. For example, production systems which are described in this way are much more agile. They can react faster to changes in demand and can be reconfigured easily and quickly. The resource descriptions also improve the sustainability of production systems because they provide detailed information about the exact capabilities and characteristics of all the available resources. This means that production system designers are better placed to utilise ready-made modules, (design by re-use). Being able to use readily available production modules means that the Time to Market and Time to Volume are improved, as new production systems can be built or reconfigured using tested and fully operational modules, which can easily be integrated into an already operational production system. Finally, the resource descriptions are an essential source of information for auto-configuration tools, allowing automated, or semi-automated production system design. However, harvesting the full benefits of all these outcomes requires that the tools used to create new production systems can understand and utilise the modular descriptions proposed by this concept. This, in turn, presupposes that the all the formalised descriptions of the production modules provided here will be made publicly available, and will form the basis for an ever-expanding library of such descriptions

    Toolchain and workflow for the design of an ISO 11783-compatible ECU based on ISOAgLib

    Get PDF
    This paper describes a basic toolchain for the design of an ISO 11783-compatible electronic control unit (ECU), from its conception to the implementation of a working embedded prototype, along with a suggested workflow for dividing application programming, mask design and hardware-related tasks in a debugging-friendly and time-efficient manner. The toolchain is centered on the open source ISOAgLib programming library distributed and maintained by OSB AG and the paper will refer to other specific tools and devices, but is otherwise intended to provide a general introductory overview of the process rather than focus on specific vendors or platforms.IV Workshop procesamiento de señales y sistemas de tiempo real.Red de Universidades con Carreras en Informática (RedUNCI

    Toolchain and workflow for the design of an ISO 11783-compatible ECU based on ISOAgLib

    Get PDF
    This paper describes a basic toolchain for the design of an ISO 11783-compatible electronic control unit (ECU), from its conception to the implementation of a working embedded prototype, along with a suggested workflow for dividing application programming, mask design and hardware-related tasks in a debugging-friendly and time-efficient manner. The toolchain is centered on the open source ISOAgLib programming library distributed and maintained by OSB AG and the paper will refer to other specific tools and devices, but is otherwise intended to provide a general introductory overview of the process rather than focus on specific vendors or platforms.IV Workshop procesamiento de señales y sistemas de tiempo real.Red de Universidades con Carreras en Informática (RedUNCI

    Toolchain and workflow for the design of an ISO 11783-compatible ECU based on ISOAgLib

    Get PDF
    This paper describes a basic toolchain for the design of an ISO 11783-compatible electronic control unit (ECU), from its conception to the implementation of a working embedded prototype, along with a suggested workflow for dividing application programming, mask design and hardware-related tasks in a debugging-friendly and time-efficient manner. The toolchain is centered on the open source ISOAgLib programming library distributed and maintained by OSB AG and the paper will refer to other specific tools and devices, but is otherwise intended to provide a general introductory overview of the process rather than focus on specific vendors or platforms.IV Workshop procesamiento de señales y sistemas de tiempo real.Red de Universidades con Carreras en Informática (RedUNCI

    Embedded workbench application of GPS sensor for agricultural tractor.

    Get PDF
    This paper presents a design of an embedded workbench application of Global Positioning System (GPS) for agricultural tractor. Electronic Control Unit (ECU) is Global Positioning System (GPS) sensor using IAR (IAR Embedded Workbench) and an open source library which follows the most important characteristics of International Organization for Standardization (ISO) 11783 communication protocol in the serial communication network of agricultural vehicles. These applications are written in C/C++ programming methods. We explain some test connection configuration between working Personal Computer (PC) and test board for studying the application program and GPS sensor working status. This research work mainly describes the system architecture and programming methodology of an application program which follows some standards for agricultural machinery

    Embedded Control System for Agricultural Machinery implemented in Forage Harvesting

    Get PDF
    Koneiden tehokas käyttö on erityisen tärkeää rehunkorjuussa lyhyen korjuuajan ja koneiden kalleuden takia. Parhaan tehokkuuden saavuttamiseksi noukinvaunun kaltaisen korjuukoneen kuormituksen tulisi olla optimaalinen. Ylikuormitustilanteessa noukin voi tukkeutua, kun taas alikuormitus kuluttaa aikaa ja heikentää rehusilpun laatua. Laatua voidaan myös parantaa säilöntäaineen tarkalla annostelulla. Tässä diplomityössä kehitettiin kaksi ISO 11783 ohjainta parantamaan rehunkorjuun tehokkuutta. Ohjaimet kehitettiin käyttäen työkaluketjua, joka on suunniteltu ISO 11783 ohjainten kehitykseen. Työkaluketjun pääosat ovat Matlab Simulink C-koodin generoinnilla, PoolEdit ja siihen liittyvät parserit sekä Visual Studio ja Windows CE tietokonemoduuli. Rehun massavirtaa noukkimella estimoidaan Kalman-suotimella nopeuden, karhon koon, kuorman massan sekä kosteuden perusteella. Massaestimaatin perusteella säilöntäainetta voidaan levittää rehuun siten, että säilöntäaineen ja rehun suhde on optimaalinen. Traktorin nopeutta säädetään sumealla säätimellä koneen kapasiteetin, estimoidun massavirran sekä karhon koon perusteella. Lopputuloksena massavirta pysyy optimaalisena riippumatta karhon koon muutoksista eikä tukoksia pääse syntymään. Peltotesteissä laitteiston todettiin toimivan määrittelyn mukaisesti.Efficient use of machines is especially important in forage harvesting due to the short harvesting period and expensive machinery. To achieve the best efficiency, a harvesting machine, such as a loader wagon, should be used with optimal loading. Whereas overloading the machine can cause blockages in the cut-and-feed unit, underloading consumes more time and reduces the quality of the resulting silage. In addition, the quality can be improved by optimizing the dosage of the additive. In this thesis, two ISO 11783 compatible electronic control units were implemented for optimizing the harvesting process. The electronic control units were developed using a tool chain designed for developing ISO 11783 systems. The main parts of the tool chain are Matlab Simulink with C code generation, PoolEdit with the associated parsers, and Visual Studio with a Windows CE embedded target. Mass flow of forage in the cut-and-feed unit of the wagon is estimated with a Kalman filter according to tractor speed, swath size, mass of the load, and moisture content of the forage. The mass flow estimation is used to derive the optimal spreading rate of additive so that the ratio of additive and forage is precisely what is desired. The speed of the tractor is controlled with a fuzzy controller according to the capacity of the machine, the mass flow estimation, and the swath size. As a result, the mass flow in the cut-and-feed unit is always optimal regardless of the swath size and thus no blockages will be formed. In the field tests, the performance of the system proved to be in line with the specification

    Specification, design and evaluation of an automated agrochemical traceability system

    Get PDF
    Traceability through all the stakeholders in food production is an issue of increasing importance, being specifically required by the regulations for food safety and quality (EC 178/2002), and for compliance with environmental protection. The agricultural market perceives a need for systems and technologies to automate the currently manual process of producing records of agrochemical inputs loaded into a spraying machine. A novel prototype Automated Agrochemical Traceability System (AACTS) to identify and weigh agrochemicals as they are loaded into crop sprayer has been designed, constructed, fitted to a machine and evaluated with commercial operators. The functional blocks of the system are a 13.56 MHz RFID reader, 1.4 litre self cleaning weighing funnel mounted on a 3 kg load cell, a user interface with a screen and three user command buttons (Yes, No, Back), and a progress bar made of 8 coloured LED’s (green, amber, red). The system is able to trace individual agrochemical containers, associate the product identity with national agrochemical databases, quantify the required amount of product, assist the sprayer operator and control workflow, generate records of sprayer inputs and interoperate with (recommending extensions to) task management standards as set out in ISO 11783-10. The evaluation of the quantity weighing has demonstrated that with such a system, the principal noise component is in the range of 33–83 Hz, induced by the operating tractor engine. A combined 3 Hz low pass digital filter with a second stage rolling mean of 5 values improves performance to allow a practical resolution of 1 gram (engine switched off) to 3.6 grams (sprayer fully operational) with a response appropriate to suit human reaction time. This is a significant improvement over the ±10 grams of the work of Watts (2004). An experiment with 10 sprayer operators has proved that in the majority of cases (92%) an accuracy equal or better than ±5% is achieved regardless of dispensing speed. The dispensed amounts (100.36% of target) and recorded (100.16%) are in accordance with prescribed values (100%; LSD(5%) 2.166%), where amounts dispensed by manual methods (92.61%) differ significantly from prescribed and recorded value (100%). The AACTS delivers a statistically similar work rate (211.8 s/task) as manual method (201.3 s/task; Δt = 10.5 s/task; LSD(5%) 28.2 s/task) in combined loading and recording cycle. Considering only the loading time (181.2 s/task) of manual method, the difference is 30.6 s/task (LSD(5%) 30.1 s/task). In practice this difference is believed to be marginal compared to the time required to load the water, random external events during the spraying session and in time moving, checking and storing paper records. The integrated weighing funnel concept is another significant improvement over previous work. Using this system, the mean duration of measuring per container for all tasks (34.0 s) is approximately half the time (68.5 s) achieved by Watts (2004). The AACTS was rated to be safer than the manual method regarding operator health and safety and risk of spillage. All operators who evaluated the AACTS were interested in purchasing such a system. The work confirmed that an RFID system was an appropriate media for agrochemical identification performing more than 250 product identification operations during operator tests without failure, with a speed of operation <1 s per cycle and reading distance of 100 mm. A specific format for RFID tag data is proposed for adoption, using low cost tags, that combines item level traceability with identification of products independently without access to worldwide databases. The AACTS follows ISO 11783 task management logic where a job is defined in a prepared electronic task file. It is proposed to extend the ISO 11783-10 task file to integrate the records provided by AACTS by handling the tank loads as individual products resulting from loading task and allocating them to spraying tasks. It is recommended to produce a production prototype following the design methodology, analysis techniques and performance drivers presented in this work and develop the features of user interface and records of tank content into software for ISO 11783-10 cabin task controller to deliver business benefits to the farming industry. The results with RFID encourage the adoption of RFID labelling of agrochemical containers. The reader may wish to read this thesis in parallel with Gasparin (2009) who has considered the business and industry adoption aspects of the AACTS.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
    corecore