This work has been carried out at BAE Systems in Örnsköldsvik. The background to the work is that BAE Systems is developing a hybrid electric driveline for the BvS10 tracked vehicle (Sirius project), but lacks the necessary drawings, i.e. a 3D model, for the construction of this vehicle. The purpose of the work was to create data regarding the 3D model, weight, center of gravity and inner volume analyzes for the future construction of this hybrid-driven tracked vehicle. A 3D model of a complete BVs10 front cab with hybrid drivetrain was created by removing all systems that belonged to the old driveline in the original 3D model and then replacing them with new drivetrain components for a hybrid-driven tracked vehicle. In order for the components that belonged to the hybrid driveline to fit and meet the weight and volume requirements, large relocations of components inside the vehicle had to be carried out. When comparing the weight and volume between the original platform and the new hybrid-driven platform, all data were calculated based on what happens to the vehicles center of gravity in the horizontal and vertical axis with regard to the vehicles direction of travel. Two concepts were developed in this work regarding service weight, center of gravity and internal volume. Notwithstanding the concept, the parameters are improved compared to the original construction, which shows that the Sirius concept improves the properties of the tracked vehicle with regard to the technical requirements placed on the project. The requirements are seen as met as the results presented in this report show that the Sirius concept improves the vehicle`s characteristics regarding weight, center of gravity and volume, which means that this work is seen as successful. The result of this report is something that BAE will use in future development. / Detta examensarbete har utförts på BAE Systems i Örnsköldsvik. Bakgrunden till arbetet är att BAE Systems utvecklar en hybridelektrisk drivlina på bandvagnen BvS10 (Sirius projekt), men saknar tillhörande konstruktionsunderlag för detta fordon. Syftet med arbetet var att skapa underlag avseende 3d-modell, vikt-, tyngdpunkt- och innervolymsanalyser för den framtida konstruktionen av denna hybriddrivna bandvagn. En 3D modell av en komplett BVs10 framvagn med hybrid drivlina skapades genom att alla system som tillhörde den gamla drivlinan i den ursprungliga 3d-modellen plockades bort för att sedan ersättas av nya drivlinekomponenter för en hybriddriven bandvagn. För att de komponenter som tillhörde hybriddrivlinan skulle passa och uppfylla tyngd- och volymkraven behövdes stora omplaceringar inuti bandvagnen utföras. Vid jämförandet av vikt och volym mellan originalplattform och ny hybriddriven plattform räknades all data utifrån vad som sker med bandvagnens tyngdpunkt i horisontell och vertikal riktning med hänsyn till vagnens färdriktning. Två koncept togs fram i detta examensarbete avseende tjänstevikt, tyngdpunkt och innervolym. Oaktat koncept förbättras parametrarna jämfört med ursprungskonstruktionen, vilket visar att Sirius konceptet förbättrar bandvagnens egenskaper avseende de tekniska krav som ställts på projektet. Kraven ses som uppfyllda då resultatet som presenteras i denna rapport visar att Sirius-konceptet förbättrar bandvagnens egenskaper avseende vikt, tyngdpunkt och volym vilket gör att arbetes ses som lyckat. Resultatet i denna rapport är något som BAE kommer använda i framtida utveckling.

This thesis aims to classify the Aerodynamics of a pigeon’s tail. In this thesis two differenttheoretical solutions are implemented to solve the aerodynamics. The first is by analysingequations created by Polhamus [1], and the second theoretical analysis is done by digitalizingmoment coefficient curves by Winter [2]. The equation for the moment coefficient cm is shownin equation 1, here M is the moment q the dynamic pressure, S the wings polanform area,and c the chord leangth. A practical experiment is conducted on the pigeon’s tail where theaerodynamic forces are measured in a wind tunnel. The experimental setup included motiontracking to analyze the Angle of Attack of the tail in the wind tunnel, a force sensor, anda servo to set the angle of attack. The resulting curves show that there should exist a peakaerodynamic performance at around 30◦ spread angle and 30◦ angle of attack. The peak is found in both the theoretical and the experimental analysis. / Denna avhandling syftar till att klassificera aerodynamiken hos en duvas svans. I denna uppsatsimplementeras två olika teoretiska lösningar för att approximera aerodynamiken. Den första är genom att analysera ekvationer skapade av Polhamus [1], och den andra teoretiska analysen görs genom att digitalisera momentkoefficientkurvor av Winter [2]. Ekvationen för momentkoefficienten cm visas i ekvationen 1, här är M momentet q det dynamiska trycket, S vingarnas planformarea och c Vingprofillangden. Ett praktiskt experiment genomförs på duvans svans där de aerodynamiska krafterna mäts i en vindtunnel. Den experimentella uppställningen inkluderade rörelsespårning för att analysera anfallsvinkeln för svansen i vindtunneln, en kraftsensor och en servo för att ställa in attackvinkeln. De resulterande kurvorna visar att det borde finnas en topp aerodynamisk prestanda vid runt 30◦ spridningsvinkel och 30◦ anfallsvinkel. Toppen finns i både den teoretiska och den experimentella analysen.

No description available.

Construction machines, also referred to as engineering vehicles or earth movers, are used in a variety of tasks related to infrastructure development and material handling. While modern construction machines represent a high level of sophistication in several areas, their suspension systems are generally rudimentary or even nonexistent. This leads to unacceptably high vibration levels for the operator, particularly when considering front loaders and dump trucks, which regularly traverse longer distances at reasonably high velocities. To meet future demands on operator comfort and high speed capacity, more refined wheel suspensions will have to be developed. The aim of this thesis is therefore to investigate which factors need to be considered in the fundamental design of suspension systems for wheeled construction machines. The ride dynamics of wheeled construction machines are affected by a number of particular properties specific to this type of vehicle. The pitch inertia is typically high in relation to the mass and wheelbase, which leads to pronounced pitching. The axle loads differ considerably between the loaded and the unloaded condition, necessitating ride height control, and hence the suspension properties may be altered as the vehicle is loaded. Furthermore, the low vertical stiffness of off-road tyres means that changes in the tyre properties will have a large impact on the dynamics of the suspended mass. The impact of these factors has been investigated using analytical models and parameters for a typical wheel loader. Multibody dynamic simulations have also been used to study the effects of suspended axles on the vehicle ride vibrations in more detail. The simulation model has also been compared to measurements performed on a prototype wheel loader with suspended axles. For reasons of manoeuvrability and robustness, many construction machines use articulated frame steering. The dynamic behaviour of articulated vehicles has therefore been examined here, focusing on lateral instabilities in the form of “snaking” and “folding”. A multibody dynamics model has been used to investigate how suspended axles influence the snaking stability of an articulated wheel loader. A remote-controlled, articulated test vehicle in model-scale has also been developed to enable safe and inexpensive practical experiments. The test vehicle is used to study the influence of several vehicle parameters on snaking stability, including suspension, drive configuration and mass distribution. Comparisons are also made with predictions using a simplified linear model. Off-road tyres represent a further complication of construction machine dynamics, since the tyres’ behaviour is typically highly nonlinear and difficult to evaluate in testing due to the size of the tyres. A rolling test rig for large tyres has here been evaluated, showing that the test rig is capable of producing useful data for validating tyre simulation models of varying complexity. The theoretical and experimental studies presented in this thesis contribute to the deeper understanding of a number of aspects of the dynamic behaviour of construction machines. This work therefore provides a basis for the continued development of wheel suspensions for such vehicles. / QC 20110531

<p>Active secondary suspension in trains has been studied for a number of years, showing promising improvements in ride comfort. However, due to relatively high implementation and maintenance costs, active technology is not being used in service operation to a large extent. The objective of this study is to develop an active lateral secondary suspension concept that offers good ride comfort improvements and enables centring of the carbody above the bogies when negotiating curves at unbalanced speed. Simultaneously, the active suspension concept should be a cost-effective solution for future series production. The thesis consists of an introductory part and three appended papers.</p><p>The introductory part describes the concept of active secondary suspension together with different actuator types and control methods. Further, the present simulation model and applied comfort evaluation methods are presented. The introductory part also comprises a summary of the appended papers, an evaluation of track forces and suggestions for further work.</p><p>Paper A presents the initial development of an active lateral secondary suspension concept based on sky-hook damping in order to improve vehicle dynamic performance, particularly on straight tracks. Furthermore, a Hold-Off-Device (HOD) function has been included in the suspension concept in order to centre the carbody above the bogies in curves and hence avoid bumpstop contact. Preparatory simulations as well as the subsequent on-track tests in the summer of 2007 showed that the active suspension provides improved passenger ride comfort and has significant potential to be a cost-effective solution for future implementation.</p><p>In Paper B, measurement results from on-track tests performed in 2008 are presented. The active secondary suspension concept was slightly modified compared to the one presented in the first paper. One modification was the implementation of a gyroscope in order to enable detection of transition curves and to switch off the dynamic damping in these sections. Ride comfort in the actively suspended carbody was significantly improved compared to that in the passively suspended car. The satisfactory results led to implementation of the active suspension system in long-term tests in service operation in the beginning of 2009.</p><p>In Paper C, a quarter-car model in MATLAB has been used to investigate a more advanced control algorithm: <em>H</em>_∞ instead of sky-hook. <em>H</em>_∞ control provides more flexibility in the design process due to the possibility to control several parameters. In particular, this is done by applying weight functions to selected signals in the system. When comparing the two control strategies through simulations, the results show that <em>H</em>_∞ control generates similar carbody accelerations at the same control force as sky-hook; however, the relative displacement displacement is somewhat lower.</p>

<p>Over the past century, the automobile has become an integral part of modern industrializedsociety. Consumer demands, regulatory legislation, and the corporate need togenerate a profit, have been the most influential factors in driving forward the evolutionof the automobile. As the comfort, safety, and reliability of the automobile haveincreased, so has its complexity, and most definitely its mass.The work within this thesis addresses the twofold problem of economy and ecologywith respect to sustainable development of automobiles. Specifically, the conflictingproblems of reducing weight, and maintaining or improving noise, vibration, andharshness behaviour are addressed. Potential solutions to these problems must also beexecutable at the same, or preferably lower production costs. The hypothesis is that byreplacing acoustic treatments, aesthetic details, and complex systems of structural componentsboth on the interior and exterior of the vehicle with a single multi-functionalbody panel, functionality can be retained at a reduced mass (i.e. reduced consumptionof raw materials) and reduced fiscal cost.A case study is performed focusing on the roof structure of a production vehicle. Fullvehicle and component level acoustic testing is performed to acquire acoustic functionalrequirements. Vibro-mechanical testing at the component level is performedto acquire structural functional requirements complimentary to those in the vehiclesdesign specifications. Finite element modelling and analysis is employed to createa model representative of the as-tested component and evaluate its acoustic and mechanicalbehaviour numerically. Results of numerical simulations are compared withthe measured results for both acoustic and mechanical response in order to verify themodel and firmly establish a set of acoustic and mechanical constraints for future work.A new, multi-layered, multi-functional sandwich panel concept is proposed which replacesthe outer sheet metal, damping treatments, transverse beams, and interior trimof the existing structure. The new panel is weight optimized to a set of structural constraintsand its acoustic properties are evaluated. Results show a significant reductionin mass compared to the existing system with no degradation of the acoustic environment.A discussion of the results is presented, as is a suggestion for future research.</p>

No description available.

This thesis presents a systematic study of human responses to different motions and strategies of car body tilt control regarding ride comfort, working/reading ability and motion sickness on high-speed tilting trains. Experiments with test subjects were performed in a tilting train on curved track as well as in a moving vehicle simulator. The study is multi-disciplinary, combining knowledge and methods from the fields of railway technology, human factors and vestibular science. The main experiment in a tilting train was performed with about 75 seated test subjects, mainly students from Linköping University, making three test runs. In total, these subjects participated in about 210 individual test rides, each with a duration of about 3 hours. Additional tests on comfort disturbances with pushbutton technique have been reported in the project. The simulator experiments used a total of about 75 subjects, making some 320 test rides each of about 30 minutes duration. Test motions consisted of combinations of horizontal (lateral) acceleration and roll acceleration, together with either roll or horizontal acceleration. Rate of change of horizontal acceleration (jerk) and roll velocity were of the same order of magnitude as in a tilting train environment, but horizontal acceleration alone was about half the magnitude. Horizontal and vertical vibrations from a tilting train were added to the test motions, and train seats and interior train noise were also introduced to create a "train feeling". Test designs and methodology have been developed during the course of the experiments. The test subjects answered questionnaires, four times per test run in the train experiment and each 5 minute in the simulator experiment. The investigated variables were: estimated average ride comfort, estimated ability to work or read, and occurrence of symptoms of motion sickness (dizziness, nausea and not feeling well). Lateral and vertical accelerations together with roll motions were monitored and recorded for later evaluation. Results from the train experiments show that the estimated average ride comfort was about 4 on a 5-degree scale, which indicates “good”. Results also show that a reduced tilt compensation of the lateral acceleration while curving together with a reduced tilt velocity of the car body reduce the provocation of motion sickness. However, a reduction in tilt compensation may produce an increased number of comfort disturbances due to lateral acceleration in the car body. Regression analysis shows that motion doses from roll acceleration may be used to predict the incidence of motion sickness. The simulator experiments show that the primary sources of provocation of nausea and motion sickness are the motion doses from roll and lateral acceleration in the horizontal plane. The study proposes a hypothesis and a model of provocation of motion sickness. It is shown that motion sickness has a time decay, or leakage. A model for this leakage is proposed. The determinative types of motion for provocation of nausea and motion sickness in tilting trains are identified and future tilting train and/or simulator experiments are proposed in order to further investigate their influence. / <p>NR 20140805</p>

The thesis project is performed at ÅF Industry at their chassis department in Trollhättan, where their focus lay at chassis and body functions for the automotive industry. There are many functions in a car now a day, the act and function names for those functions have a huge variety between automotive brands. ÅF want a catalogue, with a collection of functions and what they do, how they act, pros and cons, and in- &amp; output, with focus on steering, propulsion, and suspension actuators.    Through benchmarking, all functions have been collected in a list of functions for five different automotive brands. Another student from Karlstad University, worked parallel with a similar thesis, focusing on braking actuators. Some information passed through our theses to help each other during the benchmark. From the benchmark, five datasheets were made, to add to the catalogue. Out of those five functions one had to pass the elimination matrix to be tested and evaluated.   In this thesis, the function to be tested were Drive Profile with focus on suspension. The function was tested in a Saab 9-5 Aero equipped with an VBOX 3i at NEVS test track. Test method for the test was ISO 3888-2 severe lane-change, obstacle avoidance. The result for the test was that Sport profile was stiffer than Comfort and Intelligent, and therefore recovered the roll rate much quicker in hard cornering. The profile to choose, while entry a hard cornering is the Sport profile because of the fast roll rate recovery, also the steering torque felt way better for the driver with the Sport profile activated.     It is concluded that it is a problem with all variety of function names. Especial for customer who wants to compare cars when he/she is going to buy a new car.

The report is an overview article, as a result of our investigation at the field of laser welding applied to electromobility cells manufactured in an aluminium housing. This project was proposed by the University of Skövde in collaboration with ASSAR Centre. The key results presented are based on the study of the following parameters: laser type and power, shielding gases, welding modes, patterns and layout. The conclusions of the project define the final selection of each parameter in order to achieve minimum defects and optimal electrical performance by minimizing the contact resistance.