A utilização de eletrônica embarcada na agricultura tem crescido rapidamente, tornando necessária a utilização de diversos módulos a bordo da máquina (trator e implemento). Considerando-se os impactos relacionados a esta tendência, alternativas tecnológicas devem ser geradas e devidamente exploradas, especialmente sobre os sistemas de controle e o cabeamento requeridos. As arquiteturas eletro-eletrônicas devem garantir o mínimo de custo de implementação e tempo de manutenção. Os sistemas de controle devem operar maximizando a disponibilidade das informações, o que implica a necessidade de troca de dados entre estes diversos sistemas de controle e, portanto, a existência de um protocolo de comunicação serial internacionalmente padronizado. Neste contexto, este trabalho aborda os diversos protocolos de comunicação serial - como o RS232, o RS485 e o CAN (Controller Area Network) - e as suas normas específicas, voltadas às aplicações agrícolas, como a ISO11783 e a DIN 9684, comparando-as. Dessa análise resulta a indicação da ISO11783, norma baseada no protocolo CAN, como a mais interessante para as aplicações agrícolas. Essa norma é estudada em detalhes, o que permite a criação de um roteiro de estudo e implementação do referido protocolo. Finalmente, é desenvolvida uma aplicação deste protocolo, considerando-se uma rede de comunicação de dados de um Monitor de Semeadora, a fim de demonstrar sua aplicação prática. / The use of on-board electronics in agriculture has grown quickly, requiring many electronic modules on-board machines (tractor and implement). Considering the trend related impacts, alternative technologies should be developed and used properly, especially on control systems and on the required wiring harness. Electro-electronic architectures should provide minimum implementation cost and maintenance related time. Control systems should operate maximizing the availability of information that implies on the necessity of data exchange among these variety of control systems and also, on the existence of an international standardized serial communication protocol. Considering that, this documentation covers many serial communication protocols - as RS232, RS485 and CAN (Controller Area Network) - and the agricultural applications related standards as ISO11783 and DIN 9684, comparing them. This analysis results in the indication of ISO11783, a CAN Bus based standard, as the most interesting to agricultural applications. This standard is analyzed in details, making possible the development of a protocol related study and implementation guideline. Finally, a protocol related application is developed for a Planter Monitor implement bus network, looking forward to demonstrating an ISO11783 real implementation.

Ce travail s'inscrit dans le cadre de l'évaluation de la sûreté de fonctionnement des systèmes commandés en réseau (SCR). La capacité des systèmes de commandes à compenser les effets de certaines défaillances de composants amène à redéfinir le concept de défaillances du système. La conséquence est que l'évaluation de la fiabilité prévisionnelle du système est dépendante de l'évaluation fonctionnelle et devient impossible avec les méthodes traditionnelles de la sûreté de fonctionnement. Pour surmonter ces difficultés, une approche basée sur la modélisation en vue de la simulation est proposée. Nous avons choisi les Réseaux d'activités stochastiques (SAN) largement connus dans la modélisation des protocoles de communication ainsi que dans les études de la sûreté de fonctionnement. Dans un premier temps, nous avons cherché à identifier l'incidence de deux types de défaillances fugitives : la perte d'un échantillon d'une part et le retard d'un échantillon dans la boucle de régulation d'autre part. Après, nous simulons le comportement en présence des deux types de perturbations simultanément, mettant en évidence des effets cumulatifs. Si on tient compte maintenant du fait que l'origine des pertes ou retards est due à la présence du réseau, il faut l'introduire dans le modèle. On introduit alors dans le modèle global du système la représentation SAN d'un réseau CAN et l'injection des défaillances dans celui-ci. La méthode de Monte Carlo est utilisée pour estimer les indicateurs de sûreté de fonctionnement et on montre l'influence de certains facteurs comme la charge du réseau par exemple. Nous avons proposé une méthode et les outils associés pour approcher cette évaluation par simulation et ainsi apporter une aide à la conception des systèmes satisfaisant à des exigences critiques sur certains paramètres de performance / Achieved work in this thesis deals with dependability evaluation of networked controlled system (NCS). The ability of control system to offset the effects of some components’ failure leads to redefine the concept of system failure. Consequently the reliability evaluation is dependent on functional parameters and becomes impossible with traditional dependability methods. This work aims at bringing a contribution relative to this aspect. To overcome these difficulties, an approach based on both modelling and simulation is proposed. We choose to work with stochastic activity network (SAN) widely used in modelling communication protocols as well as in dependability studies. First we sought to identify the incidence of two types of transient faults: loss of samples and delay within the control loop. Next we simulate the behaviour in the presence of two types of disturbances at the same time highlighting the cumulative effects. In fact the origin of the loss or delay information inside the control loop is due to the presence of the network, this aspect must be taken into account, that is why we introduce a new model representing the Controller Area Network (CAN) and injection of possible perturbations. Monte-Carlo method is used to estimate dependability parameters showing the influence of some factors such as network load for example. We have proposed a method and associated tools to approach this evaluation by simulation and thus provide assistance in designing systems to meet requirements on certain performance parameters

Automobile système embarqué est une architecture distribuée de l'ordinateur des applications basées sur. La prolifération des systèmes embarqués dans une automobile a apporté de nombreux avantages,tels que le remplacement du système mécanique ancienne avec capteur électronique en réseau et desactionneurs, par exemple, dans des applications telles suspensions adaptatives. Le remplacement des systèmes mécaniques avec ceux électroniques et l'intégration de nouvelles fonctionnalités dans l'électronique soulève une grave préoccupation, c'est de fournir des garanties que ces systèmes embarqués seront en mesure d'effectuer, même dans des environnements difficiles, en particulier dans un système critique pour la sécurité comme un automobile. De plus, ceux-ci l'actualité informatique applications à la demande, imposée par un processus physique.Par exemple, pour éviter un événement catastrophique comme un accident de la demande de freinage doit répondre aux contraintes de minutage. Ce qui implique que la durée de temps entre l'instance de l'application du frein (à la pédale de frein) et l'instance de l'actionnement au niveau des roues d'un véhicule automobile doit être inférieure à la limite. En outre, l'application de freinage est généralement répartie sur le nombre de nœuds, qui sont embarqués communicants les uns avec les autres en utilisant une ressource de communication partagée. Par conséquent, il est important que nous fournissons des garanties que la demande, individuellement et collectivement, est atteinte de ses contrainte temporelle; qui est dans la composition de plusieurs nœuds embarqués. En outre, la prolifération des applications informatiques est également livré avec une hétérogénéité croissante et la complexité de l'architecture intégrée, ce qui conduira à l'augmentation de la complexité de l'analyse pour les systèmes automobiles.Par conséquent, il ya un besoin croissant d'assurer que ces systèmes automobiles embarqués répondre à des contraintes temporelles et de fournir des garanties de sécurité au cours de leur fonctionnement normal ou lors de situations critiques. Cette thèse vise à développer les analyses d'ordonnançabilité pour systèmes automobiles et les réseaux intégrés, avec le but de faciliter,d'une manière rentable et fiable, la conception et l'analyse des systèmes embarqués automobiles. Les analyses sont élaborées et appliquées dans le contexte de l'automobile; de ​​façon à réduire le risque d'échec en raison de délai: les limites du matériel; frais généraux de mise en œuvre, et les interférences dues à la circulation probaliste / Automotive embedded system is a distributed architecture of computer-based applications. The proliferation of embedded systems in an automobile has brought numerous benefits; such as replacement of old mechanical system with networked electronic sensor and actuators, for example, in applications like adaptive suspensions. The replacement of mechanical systems with electronic onesand the integration of new functionality in electronics raises a serious concern; that is to provide guarantees that these embedded systems will be able to perform, even in harsh environments, particularly in a safety-critical system like an automobile.Moreover, these computer-based applications demand timeliness, imposed by a physical process. For example, to avoid a catastrophic event like a crash the braking application has to meet thetiming-constraints. This implies that the time duration between the instance of application of the brake (at brake pedal) and the instance of actuation at the wheels of an automobile should be less than the deadline. Moreover, the braking application is usually spread over number of embedded nodes, which are communicating with each other using a shared communication resource. Therefore, it is important that we provide some guarantees that an application, individually and collectively, is meeting its timing constraint; that is in the composition of multiple embedded nodes. Moreover, theproliferation of computer-based applications also comes with an increasing heterogeneity and complexity of the embedded architecture; which lead to the increase in the complexity of the analysis for the automotive systems Therefore, there is an increasing need to ensure that these automotive embedded systems meet temporal constraints and provide safety guarantees during their normal operation or during critical situations. This thesis aims at developing the schedulability analyses for automotive systems and embedded networks; with the aim to facilitate, in a cost-effective and reliable manner, the design and analysis of automotive embedded systems. The analyses are developed and applied in the automotive context; so as to reduce the risk of deadline failure due to: hardware limitations ; implementation overheads; and nterference due to probabilistic traffic

A utilização de eletrônica embarcada na agricultura tem crescido rapidamente, tornando necessária a utilização de diversos módulos a bordo da máquina (trator e implemento). Considerando-se os impactos relacionados a esta tendência, alternativas tecnológicas devem ser geradas e devidamente exploradas, especialmente sobre os sistemas de controle e o cabeamento requeridos. As arquiteturas eletro-eletrônicas devem garantir o mínimo de custo de implementação e tempo de manutenção. Os sistemas de controle devem operar maximizando a disponibilidade das informações, o que implica a necessidade de troca de dados entre estes diversos sistemas de controle e, portanto, a existência de um protocolo de comunicação serial internacionalmente padronizado. Neste contexto, este trabalho aborda os diversos protocolos de comunicação serial - como o RS232, o RS485 e o CAN (Controller Area Network) - e as suas normas específicas, voltadas às aplicações agrícolas, como a ISO11783 e a DIN 9684, comparando-as. Dessa análise resulta a indicação da ISO11783, norma baseada no protocolo CAN, como a mais interessante para as aplicações agrícolas. Essa norma é estudada em detalhes, o que permite a criação de um roteiro de estudo e implementação do referido protocolo. Finalmente, é desenvolvida uma aplicação deste protocolo, considerando-se uma rede de comunicação de dados de um Monitor de Semeadora, a fim de demonstrar sua aplicação prática. / The use of on-board electronics in agriculture has grown quickly, requiring many electronic modules on-board machines (tractor and implement). Considering the trend related impacts, alternative technologies should be developed and used properly, especially on control systems and on the required wiring harness. Electro-electronic architectures should provide minimum implementation cost and maintenance related time. Control systems should operate maximizing the availability of information that implies on the necessity of data exchange among these variety of control systems and also, on the existence of an international standardized serial communication protocol. Considering that, this documentation covers many serial communication protocols - as RS232, RS485 and CAN (Controller Area Network) - and the agricultural applications related standards as ISO11783 and DIN 9684, comparing them. This analysis results in the indication of ISO11783, a CAN Bus based standard, as the most interesting to agricultural applications. This standard is analyzed in details, making possible the development of a protocol related study and implementation guideline. Finally, a protocol related application is developed for a Planter Monitor implement bus network, looking forward to demonstrating an ISO11783 real implementation.

Den här rapporten beskriver ett examensarbete i elektroteknik på Kungliga tekniska högskolan. Syftet var att skapa en unik systemlösning där ett CAN-adapterkort (Controller Area Network) skulle integreras med ett system för övervakning av däcktryck i tunga fordon. Målet var att presentera mätvärden från ventilsensorer på en persondator. Systemet för övervakning av lufttryck heter J1939 – TPMS och är en färdig produkt. J1939 – TPMS skickar CAN-ramar på en CAN-buss i J1939-format. Dessa ramar ska läsas in av adapterkortet och presenteras på ett terminalprogram på en persondator. Arbetet har bestått av att utreda hur systemet J1939 – TPMS fungerar i detalj. Rollen för protokollet J1939 och dess förhållande till CAN har förklarats. Hur J1939-ramar tolkas och hur mätdata rörande TPMS avkodas har beskrivits i detalj. Principer för hur en CAN-nod fungerar har klargjorts. Baserat på detta har ett CAN-adapterkort konstruerats. Konstruktionen har inneburit komponentval, design av elektronikschema, design av mönsterkort och utveckling av inbyggd programvara. Resultatet blev ett färdigt och fungerande CAN-adapterkort som har testats med J1939 – TPMS. Kraven för projektet uppfylldes. Dock så kommer mer arbete med kortet och systemet behövas för att det ska bli en färdig produkt. Arbetet genomfördes hos Motion Control i Västerås AB i samarbete med Transeco Däckservice. / This report describes a degree project at the Royal Institute of Technology. The purpose was to create a unique system solution in which a CAN adapter card (Controller Area Network) was to be integrated with an air pressure monitoring system for heavy duty vehicles. The goal was to present measurement values ​​from valve sensors on a personal computer. The air pressure monitoring system is called J1939 - TPMS and is a finished product. J1939 - TPMS sends CAN-frames to a CAN-bus in J1939 format. These frames are to be read by the adapter card and presented on a terminal program on a personal computer. The job has been to investigate how the J1939 - TPMS system works in detail. The role of the J1939 protocol and its relationship with CAN has been clarified. Also, a detailed description of how J1939 frames are interpreted and how the measuring data TPMS is decoded is done. Principles for how a CAN node works has been clarified. Based on this, a CAN adapter card has been designed. The design has included component selection, design of electronics schema, design of computer cards and development of embedded software. The result was a ready-to-use CAN adapter card tested with J1939-TPMS. Requirements for the project were met. However, more work with the card will be needed to make it a finished product. The work was carried out at Motion Control in Västerås AB in cooperation with Transeco Däckservice (Transeco Tire Service).

<p>Many products are built from more or less independently developed subsystems. For instance, a car consists of subsystems for transmission, braking, suspension, etc. These subsystems are frequently controlled by an embedded computer system. In the automotive industry, as well as in other application domains, there is currently a trend from an approach where subsystems have dedicated computer hardware and other resources (a federated approach) to an approach where subsystems share hardware and other resources (an integrated approach). This is motivated by a strong pressure to reduce product cost, at the same time as an increasing number of subsystems are being introduced.</p><p>When integrating subsystems, it is desirable that guarantees valid before integration are also valid after integration, since this would eliminate the need for costly reverifications. The computer network is a resource that is typically shared among all subsystems. Hence, a central issue when integrating subsystems is to provide an efficient scheduling of message transmissions on the network. There are essentially three families of schedulers that can be used: priority-driven schedulers that assign priorities to messages, time-driven schedulers that assign specific time-slots for transmission of specific messages, and share-driven schedulers that assign shares of the available network capacity to groups of messages.</p><p>This thesis presents a framework for share-driven scheduling, to be implemented and used in embedded networks, with the aim to facilitate subsystem integration by reducing the risk of interference between subsystems. The framework is applied in the automotive domain.</p><p>The initial parts of the thesis give an overview of systems, subsystems and network technologies found and used in the automotive domain. Then, the share-driven scheduling framework is presented, analytically investigated and proven, as well as evaluated in a simulation study. Finally it is shown how the framework is to be configured and used in the context of subsystem integration. The results show that the framework allows for flexible and efficient scheduling of messages with real-time constraints, facilitating integration of subsystems from a network point of view.</p>

Controller Area Networks (CAN&rsquo / s) in vehicles need highly sophisticated software tools to be designed and tested in development and production phases. These tools consume a lot of computer resources and usually have complex user interfaces. Therefore, they are not feasible for vehicle service stations where low-performance computers are used and the workers not very familiar with software are employed. In this thesis, we develop a measurement, calibration, test and diagnosis program -diaCAN- that is suitable for service stations. diaCAN can transmit and receive messages over 3 CAN bus channels. It can display and plot the data received from the bus, import network message and Electronic Control Unit (ECU) configurations, and record bus traffic with standard file formats. Moreover, diaCAN can calibrate ECU values, acquire fault records and test vehicle components with CAN Calibration Protocol functions. All of these capabilities are verified and evaluated on a test bed with real CAN bus and ECUs.

Many products are built from more or less independently developed subsystems. For instance, a car consists of subsystems for transmission, braking, suspension, etc. These subsystems are frequently controlled by an embedded computer system. In the automotive industry, as well as in other application domains, there is currently a trend from an approach where subsystems have dedicated computer hardware and other resources (a federated approach) to an approach where subsystems share hardware and other resources (an integrated approach). This is motivated by a strong pressure to reduce product cost, at the same time as an increasing number of subsystems are being introduced. When integrating subsystems, it is desirable that guarantees valid before integration are also valid after integration, since this would eliminate the need for costly reverifications. The computer network is a resource that is typically shared among all subsystems. Hence, a central issue when integrating subsystems is to provide an efficient scheduling of message transmissions on the network. There are essentially three families of schedulers that can be used: priority-driven schedulers that assign priorities to messages, time-driven schedulers that assign specific time-slots for transmission of specific messages, and share-driven schedulers that assign shares of the available network capacity to groups of messages. This thesis presents a framework for share-driven scheduling, to be implemented and used in embedded networks, with the aim to facilitate subsystem integration by reducing the risk of interference between subsystems. The framework is applied in the automotive domain. The initial parts of the thesis give an overview of systems, subsystems and network technologies found and used in the automotive domain. Then, the share-driven scheduling framework is presented, analytically investigated and proven, as well as evaluated in a simulation study. Finally it is shown how the framework is to be configured and used in the context of subsystem integration. The results show that the framework allows for flexible and efficient scheduling of messages with real-time constraints, facilitating integration of subsystems from a network point of view.

Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Elektronik Bilgisayar Eğitimi Anabilim Dalı, 2007. / Bibliyografya var.

A variety of new features have been added in the present-day vehicles like a pre-crash warning, the vehicle to vehicle communication, semi-autonomous driving systems, telematics, drive by wire. They demand very high bandwidth from in-vehicle networks. Various electronic control units present inside the automotive transmit useful information via automotive multiplexing. Automotive multiplexing allows sharing information among various intelligent modules inside an automotive electronic system. Optimum functionality is achieved by transmitting this data in real time. The high bandwidth and high-speed requirement can be achieved either by using multiple buses or by implementing higher bandwidth. But, by doing so the cost of the network and the complexity of the wiring in the vehicle increases. Another option is to implement higher layer protocol which can reduce the amount of data transferred by using data reduction (DR) techniques, thus reducing the bandwidth usage. The implementation cost is minimal as only the changes are required in the software and not in hardware. In our work, we present a new data reduction algorithm termed as “Comprehensive Data Reduction (CDR)” algorithm. The proposed algorithm is used for minimization of the bus utilization of CAN bus for a future vehicle. The reduction in the busload was efficiently made by compressing the parameters; thus, more number of messages and lower priority messages can be efficiently sent on the CAN bus. The proposed work also presents a performance analysis of proposed algorithm with the boundary of fifteen compression algorithm, and Compression area selection algorithms (Existing Data Reduction Algorithm). The results of the analysis show that proposed CDR algorithm provides better data reduction compared to earlier proposed algorithms. The promising results were obtained in terms of reduction in bus utilization, compression efficiency, and percent peak load of CAN bus. This Reduction in the bus utilization permits to utilize a larger number of network nodes (ECU’s) in the existing system without increasing the overall cost of the system. The proposed algorithm has been developed for automotive environment, but it can also be utilized in any applications where extensive information transmission among various control units is carried out via a multiplexing bus.