This report describes a Bachelor thesis work in which a robotised laser welding cell has been modelled and simulated for the purpose of making a presentation movie. The report shows that the work has been concentrated on making the movie from the modelling phase through the recording of the movie and ending up with the editing of the final presentation movie. A pre-study was made prior the Bachelor thesis work. In the pre-study a literature study was conducted about measurement and calibration of a welding cell. Measurement of almost all equipment in the entire cell was also conducted in the pre-study.

An investigation of the heat impact of laser cutting on the material properties when producing tensile and impact test specimens of different steel types of varying thickness has been performed. The purpose of the thesis project was to provide recommendations regarding how much material that needs to be milled from the laser cut edge before tensile and impact tests. The study has been performed partly by investigating the test specimens by heat camera when the specimens were cut in the laser cutting line and partly by performing hardness tests, investigation by microscopy, and tolerance and roughness measurements and tensile tests of the laser cut material and material produced in the traditional multi operation machine. The results show that the heat affected zone in the thicker materials is greater than previously thought of, and that the currently used recommendation has to be adjusted. The study clearly shows that the thicker the material, the greater the heat affected zone, independently of the steel type, since the thicker material takes longer time to cut.

Bergvik Skog is one of the leading forest companies in Sweden who use airborne laser scanning for forestry information. They utilize laser data retrieved by the Swedish National Land Survey to describe the forest holdings and facilitate planning for thinning and final felling operations. However, the possibility to identify stands with clearing needs by using laser scanning data has not been tested in a large scale. The data used in the current study are field data from The Swedish National Forest Inventory in combination with laser data from the Swedish National Land Survey acquired in 2009. The collected data is used to find one or several laser variables that best describe the relationship of the field measured samples with clearing needs.

This master thesis includes a description of how a number of sensors are put together in a sensor platform. It also gives a description of how localization and mapping has been performed with data collected from the sensor platform. Localization is a prerequisite for most of the tasks that can be requested from an autonomous mobile robot. In many situations the GPS signal is not available and hence an additional localization system is required. One approach is to apply localization based on landmarks extracted from the robots surrounding.

An investigation of the heat impact of laser cutting on the material properties when producing tensile and impact test specimens of different steel types of varying thickness has been performed. The purpose of the thesis project was to provide recommendations regarding how much material that needs to be milled from the laser cut edge before tensile and impact tests. The study has been performed partly by investigating the test specimens by heat camera when the specimens were cut in the laser cutting line and partly by performing hardness tests, investigation by microscopy, and tolerance and roughness measurements and tensile tests of the laser cut material and material produced in the traditional multi operation machine. The results show that the heat affected zone in the thicker materials is greater than previously thought of, and that the currently used recommendation has to be adjusted. The study clearly shows that the thicker the material, the greater the heat affected zone, independently of the steel type, since the thicker material takes longer time to cut.

This master?s thesis is a remote sensing study of an area-based method used to detect forest in need of thinning by use of laser data and field samples. Only pine-dominated forest has been included in the study and height limits were set to match empirical restrictions. The study area was in the municipality of Älvsbyn (Latitude 65° 40´ N, Longitude 21° 00´ E), in northern Sweden.The Swedish authority Lantmäteriet is currently laser scanning most parts of Sweden, providing new opportunities and applications. The primary aim of the national laser scanning is to create a new elevation model, useful in consequence analysis of climate changes.

Data retrieved from airborne laser scanning represents a new source of forest data. Today, the technology has matured so that it can function in an operational environment. The aim of this study was to compile areas of application of laserdata in forestry. Moreover to analyze costs and accessibility of laserdata. The goal was to provide private forest owners information to support assessments of possible benefits of laserdata.

 The purpose with this thesis was to develop a designguideline which will simplify the development of new products that will be laser welded. The need for this thesis has come forward from the quality problems that Volvo Construction Equipment, Components Division is having with their laser welding manufacturing unit. The reason for the problems emerges from the bad communication between the development unit and the manufacturing unit within the company when the products produced today was developed. This resulted in products that were hard to and in some cases almost impossible to weld. To avoid these problems from occurring again it was needed to gather the experiences within this area and compile it and present in a brief a pedagogical manner. The information for the groundwork of our results has been gathered by interviews of several key persons in Volvo Construction Equipment, Components Division.

Test bench for air bearingsThis thesis work consisted of bringing forward and defining the test parameters relevant for a test bench and constructing a test bench that can test and verify the largest existing air bearings that are of use in Micronic Laser Systems AB machines. Because the knowledge about air bearings is limited it is thought that with the help of the test bench the knowledge would increase and in that way improve the air bearings.After learning more about air bearings and their purpose at Micronic Laser Systems AB, I started the concept phase for the test bench. For each part in the test bench I consulted my two tutors, Torbjörn Hedevärn and Johan Bergqvist, at Micronic Laser Systems AB. The final concepts where documented as 3D-modells in Solidworks and some of them have been tested in Solidworks FEM-program.The test bench is designed so that, with the help of a pneumatic cylinder, 25 kilo weights are placed on the air bearing to test its stiffness, damping and the pressure performance under its surface area. To test these parameters the test bench has to have a pressure meter, accelerometer and a microcator.

Today Holmen Skog finds and selects suitable thinning stands using data on upper height and basal area. These figures are often based on basic forest data that has been updated with the help of growth prediction models. The problem is that these figures are not always correct. The aim of this study was to investigate if a combination of data from a profiling laser and a digital camera for low elevation photography, can be used for collecting data on number of stems per ha, tree species mixture as well as basal area weighted mean height and upper height for stands. The possibility to use these data to assess the need for thinning cutting was also investigated.Laser data and aerial photographs were collected from a helicopter operating at an approximate height of 100 meters.

Laser scanning is a method of surveying that has evolved rapidly in recentyears. The technique is based on a laser scanner set up, which can document a structureusing pulsed laser beams. Each time the laser hits a surface it is partly reflectedback to the scanner that stores the point. By using strategically placed targets, storedpoints from different scans can be merged into a point cloud. A point cloud is avisualization of the scanned object with a very high accuracy.

The requirements for operative planning activities are increasing. The forest industry wants to gain better control over wood flow. A felling that is more market adjusted is desirable. However, this causes problems in the operative planning process because of the data collection methods used today. Data about timber assortments and data about the distribution of the tree diameter, etc., are often lacking. Airborne laser scanning is used to a greater extent than before for estimation of forest variables and should perhaps be used to the same extent in operative planning activities as well.

Lantmäteriet (the Swedish mapping, cadastral and land registration authority) has been laser scanning Sweden since 2009. From the laser scanned data a digital elevation model (DEM) in grid format, with a resolution of 2 m, is produced. This DEM is called GSD-Höjddata, grid 2+ and from its data and the laser point cloud itself (in the form of a las-file) contour lines can be extracted. Lantmäteriet has not yet done this, but plans to update the contour lines in their cartographic products exist. If this is to be done in a satisfactory way an evaluation of different methods for it is needed.

Lars Höglund AB is one of Scandinavia?s most qualified manufacturers of sheet metal products and provides custom designed products of very detailed precision. One of the main methods of manufacturing is laser cutting. When Lars Höglund AB signed up a new customer, with high demands in tolerances for the products, Lars Höglund AB thought it would be necessary to know the capability of the laser cutting machine. Also the process of how to retrieve this capability was interesting. The capability will be researched for the following elements: Cutting right angles in squares with a corner radius of 1 mmCutting corners which are not right angleCutting of circles with constant radius Measurements were made on 150 pieces of sheet metal details, which had been cut out by the machine.  The data from the measurements where later used to study the capability.

Sweden?s forestry legislation was updated in 2010 and a new definition of forest land was introduced. This definition was adapted to the one used by the Food and Agriculture Organization of the United Nations (FAO) for international statistics on the state of the world's forests. It is in short based on the lands ability to grow forest that reaches 5 meters, 10 % canopy closure and has a continuous distribution, according to FAO at least 0.5 hectares. A country-wide laser scanning is now carried out for the production of a new national elevation model; the laser data also provides information on forest height and density.