The purpose of this thesis is to investigate the possibility to make small, cheap and ultra low power sensor platforms, connected in wireless networks for monitoring of home and industrial environments. The concept is based on ideas from our supervisor, Jerry Lindblom. The developed system consists of a generic platform for different sensors, a receiver and software. A GPRS module from RO Rollytech AB and a database from Gema Industri AB have been modified and used to demonstrate an example of a complete system. To the platform, it is possible to connect any resistive sensor and any sensor that can act as a switch.

This paper describes the work done trying to diminish the noise present in the signal from an IR-detector. The project was aiming towards two different kinds of applications; heat protection and presence detection. The hypothesis was that the signal-noise ratio would decrease if a filter and a proper installation were used for the detector. Some experiments were executed to determine what kind of filter were the most suitable for each application and how these could be installed. After executing the experiments and evaluate the results we recommend to use a specific filter for each application.

Denna rapport behandlar utveckling av en tvåhjulig balanserande robot. En PID-regulator är implementerad i en mikrokontroller, som även AD-omvandlar en sensorsignal, samt styr motorer via H-bryggor med pulsbreddsmodulering. I rapporten förklaras framtagning av diskret PID-regulator, processorkort, motorkort, val av komponenter och sensor för att mäta robotens vinkel mot ett vertikalplan.Roboten kan balansera stillastående, men behöver kompletteras ytterligare med hjulåterkoppling för att kunna balansera medan den kör. Roboten balanserar med mätdata från en mekanisk golvavkännare (potentiometer). Andra sorters sensorer diskuteras också, t ex accelerometer, gyro och optisk sensor..

Previous studies of central tire inflation (CTI) in truck transport of roundwood have shown potential benefits to include more even wood flow and reduced road damage. The greatest benefits are found to be during periods of low bearing capacity such as spring thaw. No previous studies have examined geographical variations in the potential benefit of CTI-equipped trucks. The aim of the study was to develop and use a simple method for geographically prioritizing the use of CTI-equipped trucks within a forest company´s sector of activity.The host company for the study was Holmen Skog. The area studied consisted of Holmen Skog?s entire sector of activity extending from the province of Västerbotten to the province of Småland.

This report describes the design and construction of a prototype that automatically aims a microwave link towards a target. The link, that is located on a mobile aerial mast, is used by Saab Training Systems as a part of an infrastructure network. The report also discusses the development of a GUI that communicates with the control unit by Bluetooth.The control unit, called Pan/Tilt-controller, controls the position of the link by stepping motors. One motor controls the azimuth angle and the other one controls the elevation angle.By a GUI the operator enters the coordinates on its own position and the targets position. Hereafter a bearing is calculated and it will be sent up to the control unit.The control unit will sense its own direction by a magnetic sensor that works as an electronic compass.

This rapport is result of a project. The purpose of which was to design a circuit that is used in a heat glove. The heat glove is the technical aid which provides heat inside a glove.It is specially suited for old people who have problems with cold hands because of decreased blood circulation.There already was an old circuit in the glove that gives a constant current which develops heat from battery to glove through a circuit. The temperature is between 32 and 34 degrees.The problem with the existing circuit was to regulate the temperature. There is only on/off switch and there is no way to adjust desirable value of the temperature.In order to solve the problem the old circuit was investigated.

Denna rapport presenterar en metod som möjliggör bestämning av bredbandiga signalers infallsvinklar. Studien är gjord i Matlab där infallande signaler samplades med ett antal sensorer utplacerade ekvidistant på en rätlinje. Den samplade informationen viktades sedan med konstanter framtagna med en konvex optimeringsrutin för att bilda en vinkelberoende utsignal.Rutinerna testades för insignaler med ett få antal frekvenser och gav för alla testade insgnaler en mycket bra bestämmning av infallsvinklen. Studien visar även att det är möjligt att göra systemet mer robust mot störningar i sensorernas positioner genom att ställa kriterier på den konvexa optimerings rutinen..

To build high-rise buildings made of timber has for long been limited by national laws, due to the lack of knowledge in engineering solutions. Frame structures made of wood has for a long time been associated with major fire hazards and consequently lower safety and this connection is still being made today. The increased environmental awareness in recent years has contributed to the exploitation of indigenous building materials, including wood from our own Swedish forests and has become increasingly common. Increased knowledge about how structures behave in fire and how they can be protected in order to achieve safe timber structures has resulted in a growing interest in these structures in the construction industry. Research in the area is constantly updated and new laws allow any number of storeys in wooden buildings in Sweden as long as the performance requirements are fulfilled.The main part of this work has involved calculations of the fire resistance and load bearing capacity of floor and wall constructions.

This examination work on studies and research in articles is mostly from other countries. The purpose of the examination work have been to find out if there are any means you can work with to find out when its time to start irrigation, how they works and if they are credible. In Sweden there is not many means for decide when it?s time to irrigate and how much water you should appear. Swedish farmers think they have so much experience that they don?t need techniques like this.

This Master thesis is about a postal- and telegraphic building in Eskilstuna, Sweden. The construction methods for the specific building and buildings in general from the same time are described. The purpose of the report is to describe the loads acting on the building and how it has been built and why it has been rebuilt during the years. After this, possibilities of reconstruction and adaptation for today?s demands can be evaluated.

The global climate-change means increasing mean-temperature and higher precipitation in Sweden, which leads to shorter periods of frozen ground in the forest. At the same time the harvesting machines are getting bigger and more powerful. The forest industry aim at an even wood flow, and the ground damage has to be as low as possible. The two biggest causes for ground-damage is the bearing capacity of the forest ground and the ground-pressure of the harvesting machines. The aim of this study was to find out some rules for the machine choice considering ground pressure, when harvesting on ground with low bearing capacity.A field study, using a Valmet 890.3 forwarder, was carried out where different ground pressures and their effect on the ground were tested on two different types of ground.Additionally, an inventory of damaged harvesting grounds was made.

The master thesis, conducted at Metrima AB, concerns the development of a non-intrusivedistribution meter as a basis for individual tap water billing in apartments.The project is conducted in response to the market interest in individual tap water billing inapartments as an answer to environmental concerns regarding water consumption. Due to thehigh installation cost of traditional water meters, a new method of determining waterconsumption, without having to cut water pipes, is proposed.The proposed method distributes the total water consumption for an apartment complex toindividual apartments according to distribution meters, measuring water run-time, in eachapartment. The water run-time is estimated by measuring the water pipe?s outward vibrationsand temperature changes.A test environment was established and a prototype built, using a tilt- and vibration sensor forvibration sensing and a precision temperature sensor to measure temperature changes. As bothsensors work well in the test environment, further testing was done in 3 apartments for aduration of 5 days.

The purpose of this report is to examine various roof structures that can operate in a warehouse with large spans. The building that is examined in the report is currently under construction, and the roof construction has already been selected. The selected roof system will therefore be compared with some other structures and materials that have been possible. The report will evaluate three different frame materials, two insulating barriers and two overlaying materials. Another important part in major construction projects is the roof safety.

A method for equine intra oral radiology has been tested. In the study, both a digital system with an intraoral sensor connected to a laptop and a system utilizing image plates and digital developing was tested, initially on cadaver sculls and finally on sedated horses. The digital sensor was not considered viable for this purpose, while the system with image plates and digital developing worked very well. Two different techniques, i.e. parallel and bisectris, are suggested for the best visualization of different parts of the teeth. Intra carious injections of Mixobar oesophaghus contrast fluid was found useful when evaluating the extent of carious lesions. Compared to extra oral radiology, the new method had several advantages and can be used both in clinic and field practices..

Piled friction soil show a set-up which is increasing with the time after installation. The cost could be reduced if the set-up had been taken into account when designing but in Sweden it is very unusual to do that. Previous studies showed that set-up can vary between 25 % and 75 % during the first 90 days after pile installation. This showed that the effect of the phenomenon is difficult to predict. A study involving five projects have been carried out by specifying certain parameters like pile type, method for pile installation and test method for measure the bearing capacity in friction soils located in Sweden.