Sökning: "vehicle mean speed"
Visar resultat 6 - 10 av 25 avhandlingar innehållade orden vehicle mean speed.
6. Predictive model of perceived driving stability at high speeds under aerodynamic excitations
Sammanfattning : The automotive industry is continuously advancing towards more energy-efficient vehicle designs. Streamlined vehicles have low aerodynamic drag but have the potential to be unstable when exposed to external excitations such as unsteady aerodynamic forces created by the flow of air around them. LÄS MER
7. On Rail Vehicle Dynamics in Unsteady Crosswind Conditions : Studies Related to Modelling, Model Validation and Active Suspension
Sammanfattning : Crosswind stability of rail vehicles has been a research area for several decades, mainlymotivated by vehicle overturning accidents and higher speeds, but in recent times also byissues of lower energy consumption and track maintenance costs demanding lower vehi-cle weights. During everyday operation, rail vehicles are subjected to substantial lateralinfluences from track curves, track irregularities and crosswind, leading to large suspen-sion deflections and increased crosswind sensitivity. LÄS MER
8. In-vehicle speed adaptation - On the effectiveness of a voluntary system
Sammanfattning : The overarching aim of this thesis is to study the long term effects of a voluntary speed adaptation system, the Active Accelerator Pedal (AAP), and its effectiveness for different driver types. The papers making up this thesis are based on a study carried out on 284 vehicles and drivers in the Swedish city of Lund from 1999 until 2002. LÄS MER
9. Improving emergency braking performance of heavy vehicles
Sammanfattning : Previous studies by the Cambridge Vehicle Dynamics Consortium (CVDC) have suggested that, by improving the control bandwidth of conventional Heavy Goods Vehicle(HGV) brake actuators and using a ‘slip control’ braking strategy, HGV stopping distances could be reduced by up to 30% over existing systems. The work covered in this thesis looks to: validate the CVDC’s previous braking performance predictions through Hardware-in-the-Loop (HiL) simulation, investigate how in-plane tyre dynamics may influence such a system’s performance, develop and build a next generation high-bandwidth braking system for vehicle implementation and carry out comparative back-to-back vehicle tests between the new system and commercially available HGV ABS. LÄS MER
10. Analysis of Flow Structures in Wake Flows for Train Aerodynamics
Sammanfattning : Train transportation is a vital part of the transportation system of today anddue to its safe and environmental friendly concept it will be even more impor-tant in the future. The speeds of trains have increased continuously and withhigher speeds the aerodynamic effects become even more important. LÄS MER
