The design of the electric platform in military vehicles requires the ability to determine the best combination of power system components that support the desired operational abilities, while minimizing the size, weight, cost, and impact of the overall power system. Because prototypes are both time consuming, rigid, and costly, they have become inadequate for verifying system performance. By using simulations, engineers can best plan for and observe the associations between missions (including modes of operation and system scenarios) and system performance in a dynamic, realistic environment. This thesis proposes a new tool to analyze and design military vehicle platforms: the Advanced Mobile Integrated Power System (AMPS). This tool is useful for design and design verification of military vehicles due to its unique incorporation of mission-specific functionality. It allows the user ease of design with the ability to customize the vehicle power system architecture and components, while permitting full control over source and load input parameters. Simulation of programmed mission sequences allows the user to ensure that the chosen vehicle architecture can provide all of the electrical power and energy needed to support the mission, thus providing adequate design verification. The present thesis includes an introduction to vehicle power systems and an outline of the need for simulation, a description of the AMPS project and vehicle specifications, analytical and numerical models of the simulated vehicle, explanation of the power management system, description of the graphical user interface, and a simulation performed with the AMPS tool.

The design of the electric platform in military vehicles requires the ability to determine the best combination of power system components that support the desired operational abilities, while minimizing the size, weight, cost, and impact of the overall power system. Because prototypes are both time consuming, rigid, and costly, they have become inadequate for verifying system performance. By using simulations, engineers can best plan for and observe the associations between missions (including modes of operation and system scenarios) and system performance in a dynamic, realistic environment. This thesis proposes a new tool to analyze and design military vehicle platforms: the Advanced Mobile Integrated Power System (AMPS). This tool is useful for design and design verification of military vehicles due to its unique incorporation of mission-specific functionality. It allows the user ease of design with the ability to customize the vehicle power system architecture and components, while permitting full control over source and load input parameters. Simulation of programmed mission sequences allows the user to ensure that the chosen vehicle architecture can provide all of the electrical power and energy needed to support the mission, thus providing adequate design verification. The present thesis includes an introduction to vehicle power systems and an outline of the need for simulation, a description of the AMPS project and vehicle specifications, analytical and numerical models of the simulated vehicle, explanation of the power management system, description of the graphical user interface, and a simulation performed with the AMPS tool.

The ability of vehicles to traverse soft soils is an important aspect of their performance. The geological, climate and topography diversity originated, in Rio Grande do Sul, extensive areas of hydromorphic clay soils, as example, Planssoils and Gleissoils. When saturated of water, these soft soils present low loads support, difficult agricultural machinery work and limit the traverse of military wheeled vehicles. The aim of this study was to determine the limit of soil conditions for trafficability of military 6 x 6 wheeled trucks (Cascavel and Urutu), determine the ground pressure and predict the mobility condition from soil cone index (SCI) and vehicle characteristics. This study also proposed to evaluate the performance of a four wheel drive tractor in drawbar pull test and trafficability performance, to correlate the reduced tire inflation pressure and vehicle loading effect on slipping, drawbar pull, fuel consumption and mobility under different soil moisture conditions. It was found that the Cascavel military truck had a minimal ground pressure of 357 kPa and it needed SCI of 402 kPa in the critical layer for a single pass. The Urutu truck had a ground pressure of 401 kPa and required at least 431 kPa in SCI for one-way pass. The NATO Reference Mobility Model (NRMM) and Mean Maximum Pressure (MPP) predicting model underestimate the soil cone index required for these military vehicles to traverse soft-soils, however, MMP was more appropriate to predict the correct SIC for the tested vehicles. For the tractor experiment it was found that tire inflation pressure changed the ground pressure and the vehicle loading didn t change the ground surface pressure. The greatest drawbar pull were obtained at low tractor speed, reduced inflation pressure and high loading level, operating on hard ground. The lowest specific fuel consumption was obtained on hard ground, empty weight, low tire pressure and operating in high speed gear. The increase of soil moisture decreased the dynamic traction coefficient from 0.57 to 0.31 and the traction efficiency decrease from 50 to 37%. Reduced inflation tire pressure had positive effects on tractor mobility in waterlogged soils, reducing slipping and increasing traverse speed. Using height loading level had negative effect on wet soils because it require more engine power and increase the fuel consumption. / A habilidade de um veículo se locomover em solos com baixa capacidade de carga é um aspecto importante em seu desempenho. A diversidade geológica, climática e de relevo originou, no Rio Grande do Sul, extensas áreas de solos Hidromórficos argilosos, entre eles, os Planossolos e os Gleissolos. Quando saturados, estes solos apresentam baixa capacidade de suporte de carga, dificultando o trabalho de máquinas agrícolas e o deslocamento de veículos militares de roda. O presente trabalho teve por objetivo determinar as condições de solo limite para a trafegabilidade de veículos militares de roda com tração 6 x 6 (Cascavel e Urutu), determinar a pressão de contato pneu-solo e predizer a condição de mobilidade a partir índice de cone do solo (ICS) e das características do veículo. O trabalho também propôs avaliar o desempenho de um trator agrícola com TDA em ensaio de tração e trafegabilidade, para verificar a influência da baixa pressão interna dos pneus e a quantidade de lastro do trator sobre o patinamento dos rodados, a capacidade de tração, o consumo de combustível e a mobilidade sob diferentes condições de umidade do solo. Foi verificado que a viatura militar Cascavel exerce pressão mínima pneu-solo de 357 kPa e requer ICS de 402 kPa na camada crítica para se locomover. O veículo Urutu exerce uma pressão pneu-solo de 401 kPa e necessita de uma resistência do solo mínima de 431 kPa para o tráfego singular. Os modelos de predição de trafegabilidade de veículos militares NATO Reference Mobility Model (NRMM) e Mean Maximum Pressure (MMP) subestimam o ICS necessário para os solos estudados, porém, o modelo que mais aproximou o ICS ao requerido pelos veículos testados foi o MMP. No experimento com tratores verificou-se que a pressão interna dos pneus alterou e a adição de lastro não alterou a superfície de contato pneu-solo. Os maiores esforços na barra de tração foram obtidos em baixa velocidade de deslocamento, baixa pressão interna dos pneus e com trator completamente lastrado, operando em solo firme. O menor consumo específico de combustível foi obtido em solo firme, com trator sem lastro, baixa pressão nos pneus e operando em marcha alta. O acréscimo de umidade no solo diminuiu o coeficiente dinâmico de tração de 0,57 para 0,31 e a eficiência de tração de 50 para 37%. A utilização de baixa pressão interna nos pneus tem efeitos positivos na trafegabilidade em solos alagados, reduzindo significativamente o patinamento e aumentando a velocidade de deslocamento. A utilização de lastro no trator em condições de solo saturado tem efeito negativo, porque aumenta a demanda de potência e o consumo de combustível da operação.

[pt] Buscando a manutenção de sua capacidade operacional e a racionalização dos seus meios, o Exército Brasileiro passou recentemente por uma renovação da sua frota de veículos, incluindo veículos blindados, viaturas administrativas, como ambulâncias e automóveis, e viaturas operacionais não blindadas sobre rodas, como jipes e caminhões. Este processo de renovação possibilitou que veículos mais antigos, com mais de 15 anos de uso, fossem levados a leilões. Ocorre que nem todos os veículos são comprados nos leilões realizados, por motivos diversos, como os elevados valores de recuperação e manutenção, o baixo valor comercial, etc, ficando armazenados em pátios em áreas militares por todo o país, categorizados como sucatas, aguardando a abertura de novos processos licitatórios. Geralmente esses novos processos têm o mesmo resultado negativo, a não venda. Diante das novas aquisições de veículos já realizadas e das futuras aquisições anunciadas, mais unidades veiculares serão inutilizadas, indicando um aumento do número de sucatas militares. Nesse contexto, este trabalho realizou um estudo para destinar sucatas militares para a indústria siderúrgica, apresentando a viabilidade legal para o desfazimento de viaturas, formulando um processo sustentável, por meio do conceito de economia circular, causando impactos positivos para o meio ambiente com a eliminação de sucatas, e gerando, com esse projeto, receitas da ordem de 3,6 milhões de reais para o Exército. / [en] Seeking to maintain its operational capacity and rationalize its means, the Brazilian Army has recently undergone a renewal of its fleet of vehicles, including armored vehicles, administrative vehicles such as ambulances and automobiles, and unshielded operating vehicles on wheels, such as jeeps and trucks. This renovation process allowed older vehicles with more than 15 years of use to be auctioned. Not all vehicles are purchased at auctions held for various reasons, such as high recovery and maintenance values, low commercial value, etc., and are stored on patios in military areas throughout the country, categorized as scrap, awaiting opening of new bidding processes. Usually these new processes have the same negative result, not selling. Faced with new acquisitions of vehicles already made and future acquisitions announced, more vehicular units will be rendered useless, indicating an increase in the number of military scrap. In this context, this work carried out a study to assign military scrap to the steel industry, presenting the legal viability for vehicle depletion, formulating a sustainable process, through the concept of circular economy, causing positive impacts to the environment with the elimination of scraps, and generating, with this project, revenues in the order of 3.6 million reais for the Army.

Rapporten utforskar möjligheten till implementering av prediktivt underhåll genom maskininlärning för markfordon i svenska Försvarsmakten. Undersökningen syftade till att finna nya metoder att planera och bedriva underhåll av militära fordon. Detta baserades på en litteraturstudie där civila och militära tillämpningar av maskininlärning granskades. Därefter analyserades empirin utifrån Kent Anderssons teori om militär nytta.  Analysen visar att det ur en teknologisk synpunkt skulle vara möjligt att implementera maskininlärning för prediktiva analyser av underhåll i militära fordon. Däremot tillkommer många utmaningar kopplade till datainsamling, interoperabilitet, cybersäkerhet, krav på höga kompetenser och ett behov av avancerade algoritmer. Militär verksamhet präglas även av mycket osäkerhet och fordon nyttjas i väldigt varierande miljöer. Detta försvårar omständigheterna för en AI att förutspå framtida utfall.  För att prediktiva analyser skulle kunna nyttjas effektivt skulle Försvarsmakten behöva ändra sitt förhållningssätt till materielunderhåll. Vidare forskning är emellertid nödvändig för att undersöka en faktisk implementering, eller ett maskininlärningssystems fullständiga militära nytta. / This work explores the possibility of implementing predictive maintenance through machine learning for ground vehicles in the Swedish Armed Forces. The investigation aimed to find new methods for planning and carrying out maintenance of military vehicles. This was based on a literature review that reviewed civilian and military applications of machine learning. The empirical data was then analyzed based on Kent Andersson's theory of military utility.  The analysis shows that from a technological point of view it would be possible to implement machine learning for predictive analysis of maintenance in military vehicles. However, there are many challenges linked to data collection, interoperability, cyber security, requirements for high skills and a need for advanced algorithms. Military operations are also characterized by a lot of uncertainty and vehicles are used in very varied environments. This makes it difficult for an AI to predict future outcomes.  For predictive analyzes to become a reality, the Swedish Armed Forces would have to change their approach to maintenance. However, further research is necessary to investigate an actual implementation and the full military utility of a machine learning system.