In the automatic manual transmission system, Opticruise, the choice of gear is based on several parameters such as road incline, driving resistance and vehicle mass. Many different mass estimations are made during driving. A final vehicle mass is then used to determine the current gear. Construction vehicles are often not equipped with air suspension and can therefore not estimate the vehicle mass when standing still. If that sort of vehicle is reloaded while standing still an incorrect mass estimation will be used and as an effect of that also a wrong gear.

As trucks are getting more and more advanced, information about their weight has become a key factor for controlling them in a more fuel efficient and safe manner. Knowing the mass of a heavy duty vehicle in real time has been a difficult challenge for the truck manufacturers. With the processing power for electronic control units in trucks steadily increasing, more advanced algorithms for calculating the mass has been developed, but at the moment there still is a wish for better performance.Since there is a lack of good information regarding the external forces acting on the vehicle, forces that depends on the slope of the road, foundation of the road and the wind, the methods have to be able to disregard these. Such an approach, based on an indirect least square solution, has been evaluated in this thesis. The results have been promising and based on these a recommendation about further evaluation has been made..

The purpose of the present study was to examine effects of driver, vehicle, and environment characteristics on Collision Warning System (CWS) design. One hypothesis was made that the capability of collision avoidance would not be same among a driver, vehicle, and environment group with different characteristics. Accident analysis and quantitative analysis was used to examine this hypothesis in terms of ?risk? and ?safety margin? respectively. Rear-end collision had a stronger focus in the present study.

The low bearing capacity of roads during the spring thaw and periods in the autumn leads every year to increases costs for Holmen Skog. To reduce costs and increase accessibility Holmen Skog decided to install and test a CTI-system. Central tire inflation (CTI) is a system that makes it possible to monitor and vary a vehicle?s tire inflation pressures from the cabin, while the vehicle is in motion. When tire pressures are reduced, the area of the contact surface between the tire and the road increases, thus reducing the ground pressure. The purpose of this study was to evaluate the CTI-equipped vehicle and analyze if the CTI technology is economical defensible during the thaw 2005.

The increased travelling of today makes nodes along travelling routes more and more important. This is very much the case of petrol stations. They constitute important nodes in the road network, filling up thirsty fuel tanks and hungry stomachs, guiding road users and providing vehicle-services. In this thesis the role of the petrol station for road users was investigated in order to find out if the petrol station was a potential hot spot. We performed an ethnographic field study at a petrol station and found that a great number of visitor activities took place at the petrol station.

Heavy duty vehicles often have problems with traction during the winter periods. For vehicles that can lift tag axles it is possible to increase the normal force on the driven axle by lifting one or more tag axles, this will then increase the propulsive force of friction. This however increases wear on both road and vehicle. A possibility to reduce the wear while achieving nearly equivalent traction compared to lifted tag axles is to allow the vehicle to regulate the normal force by lowering the pressure in the air suspension associated with the tag axles or by the lifting of these axles. The vehicle would then by itself be able to set just the right amount of normal force on the drive wheels to avoid unnecessarily high normal forces while maintaining sufficient traction.The purpose of the report is to find out which parameters affect heavy duty vehicles when driving on slippery slopes and how traction can be improved.

The aim of this study is to examine possibilities and barriers for an introduction of electric vehicles in Sweden. The study has an interdisciplinary approach and thoroughly examines the essential topics which influence the future of the electric vehicle. The study reaches from answering the question on why electric vehicles lost the game to petrol cars in the early 20th century, to sketch how the difference in total cost of ownership will be between electric vehicles and petrol cars for the coming 20 years. Apart from these subjects the main topics of the study are today?s and tomorrow?s situation regarding technology, charging, fuel, market and economic incentives from an electric vehicle perspective.

In Sweden the most common type of road traffic accidents involving passenger cars are single accidents (where only one vehicle is involved). The aim of this thesis is to analyse how these accidents occur, and present recommendations on how to reduce the number of deaths. Data has been collected from the Swedish Transport Administration?s in-depth studies of fatal accidents. Road traffic accidents with fatal outcome that happened on public roads during the years 2007 to 2009 have been studied.

The purpose of this project is to get a fully functional, automatic steering system and a variable breaking system with an emergency breaking function to an Off road vehicle. This Off road vehicle is supposed to work as an aid in military situations. A team of two, Sebastian Attervall and Nichlas Gustafsson, got an order from Jonas Nyårds and the PreeRunners Project to construct a steering system that could manoeuvre an Off road vehicle without any human involvement. To make this possible the vehicle would be guided by onboard sensors, cameras and computers. The team where also assigned to construct an automatic breaking system, there also no human would be involved.

It?s a fact that the climate is affected by the vehicle that runs on the worlds roads. But theconstruction of the road itself is rarely thought of as a climate threat. Svevia and the Swedish roadadministration have opposite views of how the construction of roads should be carried thru. It?sthe difference between those two construction methods that is the base in our thesis.The amount of energy use or the emissions are not analyzed for neither the Swedish roadadministrations nor Svevias construction models.

The main purpose with the project has been to approximate the magnitude of the pollution transport from the actual road surfaces and to get an approximation of the possibility to collect the pollutants to reduce the load to the water and improve the water quality.The quantity of pollution transport from the most trafficated roads areas in Örebro city has been calculated. Roads whith a traffic exceeding 10 000 vehicle/day. The study has been done with the calculation tool StormTac. Through analysis of traffic loads and road surface, which together with a different kinds of parameters gives an approximation of the pollutant transport.The calculation has included some metals and other substances in the stormwater and has also included the present of suspended solids. Included the overall study, some smaller areas has also been calculated for the possibility to remove pollutants.The work also includes calculation for three different areas for stormwater treatment.

The demand for biogas as vehicle fuel has risen sharply and there is a great need for increased production. A possible addition of vehicle gas can be produced by upgrading landfill gas which is formed by degradation of organic waste. This thesis investigates the potential of producing vehicle fuel from landfill gas in the region of Biogas Öst.In 2008, an amount of 32 million Nm3 landfill gas was extracted in the region. This level can be maintained for another ten years if the efficiency of gas extraction is improved. The annual production will decrease with time since landfills aren?t allowed to receive more organic waste.

The interaction between the driver, the car and the road is essential for the road safety. This case study focuses on the road condition and its effect regarding road safety issues. By studying and isolating the road condition aspect and its contributing role to the accident occurrence, the aim is to explore their relationship, as well as highlight the road parameters that are commonly associated with accident occurrence. This result will be used to develop and increase awareness of the impact of poor road alignment and poor road surface conditions on traffic safety, in order to prevent these accidents from occurring. The road parameters chosen for this study include side friction, cross slope and rut bottom cross slope, road texture, curvature, drainage gradient and rutting.The case study was limited to lv 360 in Va?sterbotten, where all accidents with an unclear cause of the accident were studied, between 2003 and 2012 were carefully studied and assessed based on the condition of the road at the time of the accident.

This report discusses questions concerning wear on forest roads. The purpose of the work is to investigate if the wear on the roads will decrease when the speed limit gets lower for the trucks that transport the wood. A normal forest road, class B, was used in the study. In total 5000 m3f timber was transported on the road. Data about the road was measured with a profilograph car before and after the timber transport.

When the emissions from the diesel trucks today accounts for a large part of the total emissions from the road traffic, the trend with a more extensive use of diesel trucks for transportation will therefore lead to increasing carbondioxide emissions to the atmosphere. Because of the fact that technical progress in the form of optimized engines and shifts in the means of transport sometimes result in even greater emission levels, other solutions to this problem must be studied to decrease the emissions of carbondioxide from the diesel trucks. The purpose of the thesis is to show how a decrease of the carbondioxide emissions from diesel trucks in Sweden can be achieved in a costeffective way by the use of a carbondioxide tax and a differentiated vehicle tax. The method used in order to fullfill the purpose of the thesis is studies of literature, mainly of public government reports. Literature of enviromental economics will be used to show the need of a tax and how to determine the dynamic effective carbondioxide tax in steady-state.