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Simulation, Control and Path Planning for Articulated Unmanned Ground VehiclesYan, Yutong January 2016 (has links)
The purpose of this project is to implement obstacle avoidance algorithms to drive the articulated vehicle autonomously in an unknown environment, which is simulated by AgX Dynamics™ simulation software and controlled by Matlab® programming software. Three driving modes are developed for driving the vehicle (Manual, Semi-autonomous and Autonomous) in this project. Path tracking algorithms and obstacle avoidance algorithms are implemented to navigate the vehicle. A GUI was built and used for the manual driving mode in this project. The semi-autonomous mode checked different cases: change lanes, U-turn, following a line, following a path and figure 8 course. The autonomous mode is implemented to drive the articulated vehicle in an unknown environment with moving to a pose path tracking algorithm and VFH+ obstacle avoidance algorithm. Thus, the simulation model and VFH+ obstacle avoidance algorithm seems to be working fine and still can be improved for the autonomous vehicle. The result of this project showed a good performance of the simulation model. Moreover, this simulation software helps to minimize the cost of the articulated vehicle since all tests are in the simulation rather than in the reality.
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AutoTruck : Automated docking with internal sensorsANDERSSON, OSCAR, MOLIN, LUCAS January 2018 (has links)
The purpose of this bachelor thesis was to discover how an articulated vehicle can park itself using a pre-defined parking path with a combination of ultrasonic sensors as well as a rotary angle sensor. The project was divided into two parts: constructing a small scale demonstrator and the software controlling the demonstrator. The demonstrator was constructed from offthe- shelf components and custom parts. The truck was designed based on a rear wheel driven truck with Ackermann steering. The localization of a parking spot and measuring other distances was done with ultrasonic sensors and the hitch angle was measured by a rotary angle sensor. The performance of the demonstrator was evaluated by measuring the trailers angle difference from the center line of the parking spot. The performance was deemed to be reasonably good with successful parkings in 8 out of 10 attempts. / Kandidatarbetet syftar till att undersöka hur ett ledat fordon kan parkera sig självt efter en förbestämd parkeringsrutt med en kombination av flera ultraljudssensorer samt en vinkelgivare. Projektet består av två delar; konstruktion av ett miniatyrfordon samt mjukvaran som styr fordonet. Fordonet tillverkades från butiksköpta komponenter och skräddarsydda delar. Lastbilens design var baserad på en bakhjulsdriven Ackermannstyrd lastbil. Identifieringen av en parkeringsplats samt avståndsmätning hanterades av ultraljudssensorer och hitch vinkeln mättes av en vinkelgivare. Miniatyrfordonets prestanda utvärderades genom att mäta släpets vinkelskillnad från centerlinjen av parkeringsplatsen. Prestandan ansågs att vara tillräckligt god med lyckade parkeringar i 8 av 10 tester.
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AutoTruck : Automated docking with internal sensors / Självparkerande lastbilAndersson, Oscar, Molin, Lucas January 2018 (has links)
The purpose of this bachelor thesis was to discover howan articulated vehicle can park itself using a pre-definedparking path with a combination of ultrasonic sensors aswell as a rotary angle sensor.The project was divided into two parts: constructing asmall scale demonstrator and the software controlling thedemonstrator. The demonstrator was constructed from offthe-shelf components and custom parts. The truck was designedbased on a rear wheel driven truck with Ackermannsteering. The localization of a parking spot and measuringother distances was done with ultrasonic sensors and thehitch angle was measured by a rotary angle sensor.The performance of the demonstrator was evaluated bymeasuring the trailers angle difference from the center lineof the parking spot.The performance was deemed to be reasonably goodwith successful parkings in 8 out of 10 attempts. / Kandidatarbetet syftar till att undersöka hur ett ledatfordon kan parkera sig självt efter en förbestämd parkeringsruttmed en kombination av flera ultraljudssensorersamt en vinkelgivare.Projektet består av två delar; konstruktion av ett miniatyrfordonsamt mjukvaran som styr fordonet. Fordonettillverkades från butiksköpta komponenter och skräddarsyddadelar. Lastbilens design var baserad p°a en bakhjulsdrivenAckermannstyrd lastbil. Identifieringen av en parkeringsplatssamt avståndsmätning hanterades av ultraljudssensoreroch hitch vinkeln mättes av en vinkelgivare.Miniatyrfordonets prestanda utvärderades genom attmäta släpets vinkelskillnad från centerlinjen av parkeringsplatsen.Prestandan ansågs att vara tillräckligt god med lyckadeparkeringar i 8 av 10 tester.
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Estudo de dirigibilidade de veículos longos combinados / Handling study of heavy articulates vehiclesVieira, Januário Leal de Moraes 22 June 2010 (has links)
Apresenta um modelo completo em sistemas multicorpos de uma combinação veicular formada por um cavalo mecânico e um semi-reboque para um estudo de dirigibilidade. O modelo multicorpos foi desenvolvido no MSC.Adams/Car e inclui a suspensão primária, sistema de direção, trem de força, modelo de pneu e um quadro flexível para o cavalo mecânico, e a suspensão primária, modelo de pneu e quadro rígido para o semi-reboque. A resposta dinâmica lateral de uma composição veicular depende das características combinadas de estabilidade direcional, dirigibilidade e interação pneu/pavimento da unidade motora e da unidade rebocada. Os parâmetros mais importantes em relação à dinâmica lateral dos veículos longos combinados são: a velocidade longitudinal, o concerning stiffness dos pneus da combinação veicular, as elasticidades dos sistemas de suspensão e esterçamento do cavalo mecânico, a localização, distribuição do carregamento e momento de inércia em guinada da unidade movida e transferência lateral de carga do veículo como um todo. O modelo foi validado no âmbito dos modos de vibração. As análises de dirigibilidade foram realizadas mediante execução de manobras de mudança simples de pista e de esterçamento com entrada rampa, no MSC.Adams/Car, para calcular métricas comumente utilizadas para avaliação da dinâmica lateral de veículos longos combinados como aceleração lateral, velocidade de guinada, offtracking dinâmico e o gradiente de esterçamento. Análises dos resultados mostraram a influência no tempo de resposta, em regime transitório, do cavalo quando atrelado ao semi-reboque e um comportamento sub-esterçante nas velocidades longitudinais simuladas. A combinação veicular utilizada para este estudo apresenta um comportamento direcional estável. / This work presents a complete multibody model of a heavy articulated vehicle with a tractor and a semitrailer for handling study purposes. The model had been developed on MSC.Adams/Car and includes primary suspension system, steering system, powertrain, tire model and a flexible frame for tractor, suspension system, tire model and a rigid frame for semitrailer. The lateral dynamics response of a heavy articulated vehicle depends on tractor/semitrailer combined characteristics of the directional stability, the manouverability and the tire/road interaction. The most important parameters concerning of the lateral dynamics of heavy articulated vehicles are: longitudinal velocity, combined tire cornering stiffness of vehicular composition, suspensions systems compliance and steering system compliance of tractor, location, load distribution and yaw moment of towing unit and vehicle overall lateral load transfer. The model was validated about modal shapes and frequencies vibrations. Handling analyses had performed with single lane change and ramp steer maneuvers simulation on MSC.Adams/Car to calculate common measures for heavy articulated vehicles lateral dynamics evaluation as lateral acceleration, yaw velocity, dynamic offtracking and understeer gradient. The results analyses showed that the towing unit influences on response of the tractor and an understeer behavior of all vehicular composition over longitudinal velocity range simulated. The heavy articulated vehicle used on this study shows a stable directional behavior.
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Estudo de dirigibilidade de veículos longos combinados / Handling study of heavy articulates vehiclesJanuário Leal de Moraes Vieira 22 June 2010 (has links)
Apresenta um modelo completo em sistemas multicorpos de uma combinação veicular formada por um cavalo mecânico e um semi-reboque para um estudo de dirigibilidade. O modelo multicorpos foi desenvolvido no MSC.Adams/Car e inclui a suspensão primária, sistema de direção, trem de força, modelo de pneu e um quadro flexível para o cavalo mecânico, e a suspensão primária, modelo de pneu e quadro rígido para o semi-reboque. A resposta dinâmica lateral de uma composição veicular depende das características combinadas de estabilidade direcional, dirigibilidade e interação pneu/pavimento da unidade motora e da unidade rebocada. Os parâmetros mais importantes em relação à dinâmica lateral dos veículos longos combinados são: a velocidade longitudinal, o concerning stiffness dos pneus da combinação veicular, as elasticidades dos sistemas de suspensão e esterçamento do cavalo mecânico, a localização, distribuição do carregamento e momento de inércia em guinada da unidade movida e transferência lateral de carga do veículo como um todo. O modelo foi validado no âmbito dos modos de vibração. As análises de dirigibilidade foram realizadas mediante execução de manobras de mudança simples de pista e de esterçamento com entrada rampa, no MSC.Adams/Car, para calcular métricas comumente utilizadas para avaliação da dinâmica lateral de veículos longos combinados como aceleração lateral, velocidade de guinada, offtracking dinâmico e o gradiente de esterçamento. Análises dos resultados mostraram a influência no tempo de resposta, em regime transitório, do cavalo quando atrelado ao semi-reboque e um comportamento sub-esterçante nas velocidades longitudinais simuladas. A combinação veicular utilizada para este estudo apresenta um comportamento direcional estável. / This work presents a complete multibody model of a heavy articulated vehicle with a tractor and a semitrailer for handling study purposes. The model had been developed on MSC.Adams/Car and includes primary suspension system, steering system, powertrain, tire model and a flexible frame for tractor, suspension system, tire model and a rigid frame for semitrailer. The lateral dynamics response of a heavy articulated vehicle depends on tractor/semitrailer combined characteristics of the directional stability, the manouverability and the tire/road interaction. The most important parameters concerning of the lateral dynamics of heavy articulated vehicles are: longitudinal velocity, combined tire cornering stiffness of vehicular composition, suspensions systems compliance and steering system compliance of tractor, location, load distribution and yaw moment of towing unit and vehicle overall lateral load transfer. The model was validated about modal shapes and frequencies vibrations. Handling analyses had performed with single lane change and ramp steer maneuvers simulation on MSC.Adams/Car to calculate common measures for heavy articulated vehicles lateral dynamics evaluation as lateral acceleration, yaw velocity, dynamic offtracking and understeer gradient. The results analyses showed that the towing unit influences on response of the tractor and an understeer behavior of all vehicular composition over longitudinal velocity range simulated. The heavy articulated vehicle used on this study shows a stable directional behavior.
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Active and semi-active suspensions for articulated vehicles to minimise tyre wear / Aktiva och semiaktiva fjädringssystem för ledade fordon för att minimera däckslitageZhang, Haoran January 2021 (has links)
Tyre wear is a vital problem in vehicles, especially in articulated vehicles because of their heavier axle loads. Tyre wear can not only do harm to vehicle dynamics but also cause tyre particle emissions. Therefore, solutions that can minimise tyre wear are where this thesis work focuses. The suspension design is one of the main factors affecting tyre wear. This thesis considers different kinds of semi-active (such as ADD, SH-2 and GH-2) and active suspensions (\(H_\infty\) control) and compares them with a passive suspension with regards to tyre wear. Driving comfort and road holding are considered as well. The simulation starts by running a IPG/TruckMaker model on a route introducing a certain road roughness profile, and outputs lateral slip angles, which together with vehicle parameters and route data are input into a Simulink model. Then, based on the static vertical load on each axles of the articulated vehicle, three different quarter car models corresponding to the axles with various suspension systems are built in Simulink. Simulation results show that the active suspension (\(H_\infty\) control approach) works best in minimising tyre wear, reducing tyre wear by 1-10\% compared to the passive suspension when the vehicle is driving on road profile Class C (country road). Meanwhile, several control strategies of \(H_\infty\) control are applied in order to result in overall good vehicle performance considering comfort and road holding. Semi-active suspensions also work well in reducing tyre wear, but the amount of tyre wear reduction is lower than that of the \(H_\infty\) controllers. / Däckslitage är ett viktigt problem för fordon, särskilt för tunga ledade fordon på grund av deras högre axellaster. Däckets slitage påverkar inte bara fordonets dynamik utan orsakar också utsläpp av däckpartiklar. Olika lösningar behöver utvecklas som kan minimera däckslitage och det är fokus för detta examensarbete. Hjulupphängningens konstruktion är en viktig faktor som påverkar däckslitaget. Detta arbete studerar olika typer av semiaktiva (såsom ADD, SH-2 och GH-2) och aktiva fjädringssystem (\(H_\infty\) reglering) och jämför dem med ett passivt fjädringssystem när det gäller däckslitage, samtidigt som även körkomfort och väghållning beaktas. Simuleringarna inleds med att en IPG/TruckMaker fordonsmodell kör längs en sträcka med en viss typ av vägojämnhet. Simuleringarna resulterar i avdriftsvinklar för fordonet som tillsammans med fordonsparametrar och ruttinformation skapar indata till en Simulink-modell. Därefter, baserat på den statiska vertikala belastningen på varje axel i det ledade fordonet, skapas tre olika kvartsbilsmodeller i Simulink som motsvarar axlarna med deras olika hjulupphängningssystem.Simuleringsresultaten visar att den aktiva fjädringen (\(H_\infty\)) fungerar bäst när det gäller att minimera däckslitage, där slitaget minskar med 1-10\% jämfört med den passiva fjädringen när fordonet kör på vägprofil klass C (landsväg). Samtidigt tillämpas flera olika \(H_\infty\) reglerstrategier för att åstadkomma överlag goda fordonsprestanda även med avseende på komfort och väghållning. Semiaktiva fjädringssystem fungerar också bra för att minska däckslitaget, men minskningen av slitaget är lägre än den för den aktiva \(H_\infty\) fjädringen.
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Design těžebního sklápěcího vozidla / Design of Mining DumperTulik, Richard January 2016 (has links)
The main intent of the thesis is design of articulated mining dumper. The contet of own designed mining dumper respects technical, aesthetic and ergonomic requirements. The thesis brings a new perspective of design solution in category of currently the most powerful articulated mining dumpers.
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