[pt] A análise experimental é muito importante para se conhecer as características de Qualquer produto. Os resultados dos testes podem ser usados em pesquisas ou para serem comparados com valores padrões. No segundo caso é necessário seguir certos procedimentos que estão descritos em normas e comparar os valores das características do produto com os requisitos normalizados. No campo da Tecnologia Industrial Básica esta atividade é comumente denominada de avaliação da conformidade. Mas para se medir essas características é necessário usar instrumentos. A instrumentação é a parte mais importante neste processo porque se são usados instrumentos inadequados, o resultado da medição será incorreto e os erros poderão grandes. Então é necessário que os instrumentos tenham sido corretamente calibrados para terem exatidão adequada, baixa incerteza e garantir a repetibilidade e reprodutibilidade das medições. Metrologia é a ciência que trata da confiabilidade das medições. Nos testes veiculares acontece o mesmo, porém é necessário, também, conhecimento sobre a dinâmica veicular, para se saber como e o que será medido. O Campo de Provas da Marambaia do Exército Brasileiro possui um equipamento empregado em avaliação de veículos que mede velocidade e distância usando um sensor óptico sem contato com o solo e um sistema de aquisição de dados. Esta dissertação de mestrado apresenta uma alternativa para a Unidade Central de Processamento deste equipamento substituindo-a por um computador portátil com uma placa de aquisição e um software específico com as ferramentas para processar o sinal do mesmo transdutor óptico. Entretanto isto não é suficiente, é necessário um tratamento metrológico deste sistema de aquisição de dados para garantir a incerteza de medição e evitar os riscos de falso aceito e falso rejeito. No contexto do tratamento metrológico desenvolvido, ambos os sistemas de medição foram avaliados, o sistema originalmente em uso e o sistema alternativo proposto que o substituirá. O conhecimento das incertezas associadas constitui estratégico insumo metrológico para a importante etapa de calibração dos equipamentos utilizados. Para realizar este trabalho foi necessário unir três áreas: dinâmica veicular, instrumentação e metrologia. / [en] Experimental analysis is very important to know the characteristics of any product. The tests results can be used in researches or be compared with default values. In the second case it is necessary follow certain procedures that are described in standards and to compare the value of product s characteristics with the standard s requirements. Within the Basic Industrial Technology Domain, this activity is commonly designated as conformity assessment. But to measure these characteristics is necessary to use instruments. The instrumentation is the most important part in this process because if inadequate instruments are used, the result of the measurement will be incorrect and the errors may be great. Then it is necessary that the instruments had been correctly calibrated and have an adequate good accuracy, low uncertainty and ensure the repeatability and reproducibility of the measurements. Metrology is the science dealing with metrology reliability. In automotive tests happen the same, however it is necessary knowledge about vehicular dynamic too, to know how and what will be measured. The Brazilian Army Marambaia Proving Ground has an equipment used to vehicles evaluation that measure speed and distance using a non-contact optical sensor and a data acquisition system. This masters degree dissertation proposes an alternative for this equipment s Central Processing Unit substituting it for a laptop with a data acquisition board and a specific software with data processing tools to process the same non-contact optical sensor s signals. However this is not enough, it s necessary a metrological approach of the data acquisition system to ensure the uncertainty of measurement and avoid false accept risk and false reject risk. In the context of the developed metrological approach, both the measurement systems were evaluated, the system originally in use and the alternative system proposed that will substitute the first. The knowledge about the associated uncertainties constitute a strategic resource to the important stage of the used equipment s calibration. To carry through this work it was necessary to join three areas: vehicular dynamic, instrumentation and metrology.

Climate change is a significant issue in today's society as countries work towards decarbonising the economic sectors that contribute to significant greenhouse gas emissions. The electric vehicle (EV) is proposed as a solution to reduce the level of emissions in the transport sector. However, if an EV is powered by an electrical fossil fuelled source, their penetration into the UK market will have minimal mitigating effects, as emissions will simply shift from the transport sector to the energy production sector. Limited research has evaluated the loss of propulsion energy as a result of operating on-board climate control systems, and has focused more on traction energy. Unlike conventional fossil fuelled vehicles, EVs do not produce waste heat to warm the interior space of the vehicle. The present research found that up to 30% of a vehicle's total energy consumed per trip is allocated to heating requirements, thus the present research developed a temperature predicting numerical algorithm to compute indoor cabin temperatures. The vehicle was exposed to ambient climate conditions with an auxiliary heating or cooling system to evaluate this thermal model. The numerical algorithm could predict the temperature of a cabin space under solar space heating conditions with 62% more accuracy than previously developed models when comparing the Root Mean Square Error performance indicator. The presently developed temperature prediction algorithm may be applied to a route planning application, thus indicating the electrical energy required by the vehicle's battery for users to increase or decrease the desired temperature level. Additionally, this study investigated the ability of a renewable energy resource to decarbonise the vehicle's built-in climate control system. Integrating solar panels on the roof and bonnet of an EV to power an auxiliary climate control system reduced the electrical loading required to reach the occupant's thermal comfort. By installing an auxiliary heating system to increase cabin temperature by 2 or 5°C, the present research found that energy consumption of the built-in climate control system was reduced by 22% or 57%, respectively. This illuminates the potential an auxiliary climate control system has in improving the thermal performance of EVs.

It is crucial to find a good balance between positioning accuracy and cost when developing navigation systems for ground vehicles. In open sky or even in a semi-urban environment, a single global navigation satellite system (GNSS) constellation performs sufficiently well. However, the positioning accuracy decreases drastically in urban environments. Because of the limitation in tracking performance for standalone GNSS, particularly in cities, many solutions are now moving toward integrated systems that combine complementary sensors. In this master thesis the improvement of tracking performance for a low-cost ground vehicle navigation system is evaluated when complementary sensors are added and different filtering techniques are used. How the GNSS aided inertial navigation system (INS) is used to track ground vehicles is explained in this thesis. This has shown to be a very effective way of tracking a vehicle through GNSS outages. Measurements from an accelerometer and a gyroscope are used as inputs to inertial navigation equations. GNSS measurements are then used to correct the tracking solution and to estimate the biases in the inertial sensors. When velocity constraints on the vehicle’s motion in the y- and z-axis are included, the GNSS aided INS has shown very good performance, even during long GNSS outages. Two versions of the Rauch-Tung-Striebel (RTS) smoother and a particle filter (PF) version of the GNSS aided INS have also been implemented and evaluated. The PF has shown to be computationally demanding in comparison with the other approaches and a real-time implementation on the considered embedded system is not doable. The RTS smoother has shown to give a smoother trajectory but a lot of extra information needs to be stored and the position accuracy is not significantly improved. Moreover, map matching has been combined with GNSS measurements and estimates from the GNSS aided INS. The Viterbi algorithm is used to output the the road segment identification numbers of the most likely path and then the estimates are matched to the closest position of these roads. A suggested solution to acquire reliable tracking with high accuracy in all environments is to run the GNSS aided INS in real-time in the vehicle and simultaneously send the horizontal position coordinates to a back office where map information is kept and map matching is performed.

Obemannade markfarkoster är ännu ganska ovanliga i den svenska Försvarsmakten men borde kunna bli allt vanligare. UGV:er används traditionellt till att utföra smutsiga, tråkiga och farliga arbetsuppgifter. Kan de då vara användbara i Afghanistan mot den motståndare som FM möter där idag? I studien undersöker författaren möjligheterna för obemannade markfarkoster att bidra med militär nytta inom området logistiktransporter. De obemannade transportfordonen kan från grunden utgöras av standardlastbilar i FM som har utrustats med så kallade UGV-kit. Dessa UGV-kit har till uppgift att göra standardfordonen fjärrstyrda, autonoma eller både och. Samma princip gäller för eskortfordonen som följer med till stöd för logistiktransporten, en Galt ska exempelvis kunna agera UGV. Den irreguljära och lågteknologiska motståndaren använder ofta IED:er vid eldöverfall vilket har gjort landsvägstransporter till riskfylld verksamhet för personal ute på vägarna. Personalsäkerhet är prioriterad verksamhet i Försvarsmakten och författarens antagande är att UGV:er kan bidra till att göra logistiktransporter och eskortförfaranden till mindre riskabel verksamhet. / Unmanned ground vehicles are still quite rare within in the Swedish Armed Forces but they should become more common. UGV´s are used traditionally for performing dirty, dull and dangerous tasks. Could they also be usefull against the enemy in Afghanistan that the Swedish Armed Forces are confronting there today? In this study the author investigates the possibilities for unmanned ground vehicles to contribute with military benefits to the area of logistics transportation. The unmanned transport vehicles can be ordinary standard trucks from the beginning which have been equipped with a so called UGV-kit. This UGV-kit´s task is to make the standard vehicles remotely controlled, autonomous or both. The same principle applies to the escorting vehicles, a Galt should for example also be able to act as a UGV. The irregular and low technology enemy often uses IED’s when attacking, which have made road transportation to hazardous activities for the personnel on the road. Personnel safety are prioritized activity within the Swedish Armed Forces, and the authors assumtion is that UGV’s can help making logistics transportation and escorting procedures in to less risky activities.

Veículos autônomos são objeto de crescente estudo em todo o mundo. Face à Engenharia de Transportes, é tema que deve provocar uma revolução nas próximas décadas, pois é concreta a tendência ao uso destes veículos na sociedade. Podem se citar como grandes beneficiados a segurança, a logística, o fluxo de trânsito, o meio ambiente e também os portadores de deficiências. Com o objetivo de fazer um veículo atingir um ponto com coordenadas conhecidas de forma autônoma, uma plataforma veicular terrestre em escala foi utilizada, a qual recebeu um sistema computacional micro controlado e tecnologias para proporcionar mobilidade através de motores elétricos para tração e servo-motores para direcionamento; posicionamento por satélite através de receptor GNSS e bússola eletrônica para orientação; sensoriamento por ultra-som para evitar colisões; e comunicação sem fio, a fim de se realizar remotamente monitoramento e instrução em tempo real através de um aplicativo para computador pessoal (PC). Foi desenvolvido um algoritmo de navegação que, fazendo uso dos recursos disponíveis, proporcionou autonomia ao veículo, de forma a navegar para pontos com coordenadas conhecidas sem controle humano. Os testes realizados visaram avaliar a capacidade de autonomia do veículo, a trajetória de navegação realizada e a acurácia de chegada aos pontos de destino. O veículo foi capaz de atingir os pontos em todos os testes realizados, sendo considerado funcional seu algoritmo de navegação e também os sistemas de mobilidade, posicionamento, sensoriamento e comunicação. / Autonomous vehicles are an on growing research target around the world. Face to Transports Engineering, it is a subject which is expected to make a revolution on the next decades. The great benefits are on security, logistic, traffic flow, environment and handicap. With the goal to make a vehicle navigate autonomously to known geodesics coordinates, a reduced scale terrestrial vehicular platform was used. This platform received a microcontrolled computational system and technologies to give it mobility, through electrical motors for traction and servo-motors for direction; satellite positioning, through a GNSS receiver and magnetic compass for orientation; ultrasound sensing in order to avoid collision; and wireless communication, in order to do remote monitoring and instruction at real time through a PC application. It was developed a navigation algorithm which, from the available resources, gave autonomy to the vehicle, in order to navigate to known geodesics coordinates without human control. The test set was intended to evaluate the autonomy capacity of the vehicle, the navigation trajectory that was done and the arrival accuracy to the destination points. The vehicle reached the destination points on all tests done, being evaluated as functional its navigation algorithm and also the mobility, positioning, sensing and communication systems.

Autonomous ground vehicles (AGVs) is a growing field within research. AGVs are used in areas like reconnaissance,surveillance, transportation and self-driving cars. The goal of this project is to drive a system of five AGVs modelled as differential drive vehicles along an arbitrary path through a field of obstacles while holding a formation. The goal is achieved by dividing the project into three subprojects. The first subproject is trajectory tracking of one AGV. This is achieved by using the differentialdrivemodel and driving the tracking error of the system to zero.The second subproject is formation control, where a displacement-based, double integrator model is used to get five AGVs to hold a formation of an equilateral triangle while following a path.The third subproject is collision avoidance between AGVs and static obstacles placed along the predetermined path. Collision avoidance is achieved by adding a repulsive potential field around the AGVs and obstacles. All three subprojects are then combined to achieve the goal of the project. Finally, simulations are done in Matlab which confirms that the proposed models are correct. / Autonoma vägfordon är ett växande område inom forskning. Autonoma vägfordon används inom områden som spaning, övervakning, transportering och självkörande bilar.Målet med det här projektet är att köra ett system med fem autonoma vägfordon modellerade som differentialdrivna fordon längsmed en slumpmässig väg genom ett fält med hinder samtidigt som de håller en formation. Målet uppnås genom att dela upp projektet i tre delprojekt. Det första delprojektet är banspårning med ett autonomt vägfordon. Det görs genom att använda den differentialdrivna modellen och driva systemets spårningsfel till noll. Det andra delprojektet är formationshållning där en förskjutningsbaserad dubbelintegratormodell används för att få fem fordon att följa en väg samtidigt som de håller formen av en liksidig triangel. Det tredje delprojektet handlar om att undvika kollision mellan fordonen och statiska hinder som placerats på vägen. Kollisionsundvikning uppnås genom att lägga på ett repellerande potentialfält runt alla agenter och hinder. Alla tre delprojekt kombineras sedan för att lösa projektmålet. Slutligen görs simuleringar i Matlab vilket bekräftar att de framtagna modellerna är korrekta. / Kandidatexjobb i elektroteknik 2022, KTH, Stockholm

No description available.

As autonomous ground vehicles grow in popularity,it is of interest to study how they could coordinate together andhow the technical systems can be implemented in a safe andeffective manner. The objective of this report is to examine howto autonomously move a formation of vehicles without collisionswith obstacles or other vehicles. This is done by considering threefundamental aspects: trajectory tracking, formation control andcollision avoidance. Firstly a trajectory tracking controller for anindividual vehicle is implemented, with the function of followinga desired trajectory. Secondly a displacement-based formationcontrol is explored for two models, the double-integrator modeland the nonholonomic model, with the objective of coordinatingmultiple vehicles to keep a certain formation. Lastly collisionavoidance is integrated in the formation control by adding arepulsive term to the formation controller. It is shown thatthe agents maintained formation while avoiding collision withobstacles and other agents. The implemented controllers wereverified through simulations in MATLAB. / Eftersom autonoma markfordon blir allt mer vanligt är det vikt att studera hur de kan samordna tillsammans och hur de tekniska systemen kan implementeras på ett säkert samt effektivt sätt. Syftet med denna rapport är att undersöka hur man autonomt kan flytta en formation av fordon utan kollisioner med hinder eller med andra fordon. Detta görs genom att tre grundläggande aspekter övervägs: projektilspårning, formationshållning och kollisionsundvikande. Först implementeras en regulator för projektilsspårning, där funktionen är att följa en önskad bana. Därefter undersöks två modeller inom förskjutningsbaserad formationshållning, med ambitionen att samordna alla fordon för att behålla formationen. Slutligen så integreras metoder för kollisionsundvikning med formationshållning genom att lägga till bortstötande teknik i regulatorn för formationshållning. Det visades att fordonen lyckades med att upprätthålla formationen samtidigt som kollisioner mellan hinder och andra fordon undveks. De implementerade regulatorerna verifierades genom simuleringar i MATLAB. / Kandidatexjobb i elektroteknik 2021, KTH, Stockholm

The usage of autonomous ground vehicles is growingextensively. Therefore, it is important to gain a better understand-ing for the fundamentals of their communication network. Inthis paper, three important areas will be considered: Trajectorytracking, formation control and collision avoidance. Firstly,trajectory tracking is implemented for unicycles to direct them toa reference path. Secondly, formation control is examined for twoapproaches: A method based on virtual structure with a presettrajectory for unicycles and a method based on displacement forpoint agents. Finally, collision avoidance is incorporated withthe displacement-based controller. For this case, agents keepformation without colliding within formation and with staticobstacles in the workspace. The proposed controllers are verifiedthrough simulations in MATLAB. / Användningen av autonoma markfordon har ökat kraftigt de senaste åren. Således är det viktigt att få en bättre förståelse för grunderna i deras kommunikationsnätverk. I detta projekt studeras tre essentiella områden: projektilspårning, formationshållning och undvikning av kollisioner. Först och främst implementeras projektilspårning för en enhjuling där den styrs mot en önskad projektilbana. Därefter betraktas formationshållning genom två metoder: Den första metoden handlar om virtuella strukturer med en förutbestämd bana för enhjulingar. Den andra metoden baseras på en förskjutningsbaserad regulator. Slutligen införs undvikning av kollisioner tillsammans med den förskjutningsbaserade regulatorn för att uppnå ett kollisionsundvikande robotsystem. Samtliga objektiv inom de tre områdena nås med varierande precision. / Kandidatexjobb i elektroteknik 2020, KTH, Stockholm

Advanced Driver Assistance Systems (ADAS) and Autonomous Ground Vehicles (AGV) have the potential to increase road transportation safety, environmental gains, and passenger comfort. The advent of Electric Vehicles has also facilitated greater flexibility in powertrain architectures and control capabilities. Path Tracking controllers that provide steering input are used to execute lateral maneuvers or model the response of a vehicle during cornering. Direct Yaw Control using Torque Vectoring has the potential to improve vehicle's transient cornering stability and modify its steady state handling characteristics during lateral maneuvers. In the first part of this thesis, the transient dynamics of an existing baseline Path Tracking controller is improved using a transient Torque Vectoring algorithm. The existing baseline Path Tracking controller is evaluated, using a linearized system, for a range of vehicle and controller parameters. The effect of implementing transient Torque Vectoring along with the baseline Path Tracking controller is then studied for the same parameter range. The linear analysis shows, in both time and frequency domain, that the transient Torque Vectoring improves vehicle response and stability during cornering. A Torque Vectoring controller is developed in Linear Adaptive Model Predictive Control framework and it's performance is verified in simulation using Simulink and CarSim. The second part of the thesis analyzes the tradeoff enabled by steady state Torque Vectoring between improved limit handling capability through optimal tire force allocation and drivability demonstrated by understeer gradient. Optimal tire force allocation prescribes equal usage in all four tires during maneuvers. This is enabled using steering and Torque Vectoring. An analytical proof is presented which demonstrates that implementation of this optimal tire force allocation results in neutralsteering handling characteristics for the vehicle. The optimal tire force allocation strategy is formulated as a minimax optimization problem. A two-track vehicle model is simulated for this strategy, and it verified the analytical proof by displaying neutralsteering behavior. / Master of Science / Advanced Driver Assistance Systems (ADAS) and Autonomous Ground Vehicles (AGVs) have the potential to increase road transportation safety, environmental gains, passenger comfort and passenger productivity. The advent of Electric Vehicles (EVs) has also facilitated greater flexibility in powertrain configurations and capabilities that facilitate the implementation of Torque Vectoring (TV), which is a method of applying differential torques to laterally opposite wheels to enhance the cornering performance of ground vehicles. Path Tracking (PT) controllers that provide steering input to the vehicles are traditionally used for lateral control in AGVs and ADAS features. The goal of this thesis is to develop Torque Vectoring algorithms to improve a vehicle's stability and shape its steady state behaviour through a corner during low lateral acceleration maneuvers. An existing baseline Path Tracking controller is selected and evaluated. The effect of implementing Torque Vectoring along with this Path Tracking controller is studied and it is found to improve the stability of the vehicle during cornering. This is verified in simulation by designing and implementing the Torque Vectoring algorithm. Finally, a Torque Vectoring strategy is proposed to manage the handling of the vehicle during low acceleration cornering.