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1	Elstart Motorsåg Martinsen, Dan, Danielsson, Henrik Unknown Date (has links) <p>As requested by the company Husqvarna AB, we have developed a prototype of an electrical start device to a chainsaw. </p><p>This was done through the development of new details in Catia, which has been integrated with existing details. Electrical components have been purchased by HAB electronics.</p><p> </p><p>In parallel with the modeling calculations was done, which was the basis for determine dimensions and the choice of an electric motor and gears. </p><p>Prototype 1 improved gradually and led to prototype number 2, which became the final result. </p><p>Prototype 2 made the chainsaw start, which was the goal of the project.</p> Electrical starter Chainsaw Husqvarna AB
2	Elstart Motorsåg Martinsen, Dan, Danielsson, Henrik Unknown Date (has links) As requested by the company Husqvarna AB, we have developed a prototype of an electrical start device to a chainsaw. This was done through the development of new details in Catia, which has been integrated with existing details. Electrical components have been purchased by HAB electronics. In parallel with the modeling calculations was done, which was the basis for determine dimensions and the choice of an electric motor and gears. Prototype 1 improved gradually and led to prototype number 2, which became the final result. Prototype 2 made the chainsaw start, which was the goal of the project. Electrical starter Chainsaw Husqvarna AB
3	Correlation between chainsaw type and tool marks in sectioned bone Moore, Gregory 22 January 2016 (has links) This research determined if the patterns resulting from different chainsaw chain types impacting bone leave tool marks are dissimilar enough from one another to determine which type of chainsaw was used in dismemberment mimicking homicide cases. Multiple styles of commercially available chainsaw chains were used. The long bones of adult white tailed deer (Odocoileus virginianus) were cut to produce false start cuts and complete sectioning to mimic typical human dismemberment. The cut areas were examined macroscopically and microscopically to note features common to each chain. The chains were compared to one another to note differences. It was proposed that each chainsaw would leave different tool marks. It was found that the style of tooth significantly affects the size of the exit chipping, size of the breakaway notch, angling of the kerf floor, and the mass of bone wastage produced. The most significant differences were produced with a standard tooth. The skip of the chainsaw did not create significant differences. This research has applications in forensic anthropology through the additional information on tool marks and the ability to identify specific tool types. The information is also useful to law enforcement investigations involving dismemberments. Forensic anthropology Chainsaw Tool marks Trauma
4	Rotational system with variable inertia Sjunka, Albin, Larsson, Samuel January 2022 (has links) Chainsaws have seen a constant improvement over the time of their production and are still an object of improvement by the bigger chainsaw companies. The chainsaw engine is highly developed and optimised for the assigned uses. This thesis project aims to further optimise the engine by implementing a system that allows for variable inertia on the rotational system. A high inertia is needed at higher velocity to reduce speed fluctuations but a high inertia also makes it harder for an object to accelerate, a low start inertia could help accelerate the system and then reach a higher inertia for stability at higher velocities. The variable inertia system were developed for a Husqvarna 550 XP mk.II. Concepts were developed using the product development process and the evaluation is based on the interpreted needs of the product. The most promising concepts underwent dynamic system simulations to ensure the best performing concept is selected. The chosen concept were then further designed with an iterative process where each iteration was analysed with the finite element method to ensure structural rigidity. The developed product indicates a performance increase. The magnitude of this performance increase is mainly governed by the size constraints in the chainsaw. Variable inertia flywheel chainsaw Mechanical Engineering Maskinteknik
5	A Study of Small Engine Testing Josefsson, Eric, Henningsson, Henrik January 2015 (has links) Today the environmental issues are a lot on the agenda and the environmental awareness are more and more common. New laws and restrictions on engines emissions are enforced and the demand on the engines gets higher and tougher. This leads to the engine testing playing a more crucial part than ever. Engine tests are done using an engine dynamometer. The dynamometer loads the engine by, in many different ways, absorbing the power and torque generated by engine. The most important functions of a dyno are to convey the power from the engine to the dyno, to load the engine, to measure the power and torque generated by the engine and to remove the excess heat that is generated. Husqvarna is a Swedish company that produces garden and forest cutting tools, their most famous products are their chainsaws. Husqvarna does an extensive amount of engine testing, long time testing, functional testing and field testing. Some functional tests, such as start-ability after use is done in a climate chamber where the humidity and temperature can be set. Today, loading a chainsaw in -25 °C is a problem due to the fact that the most used dynamometer at Husqvarna is a water brake that freezes in minus degrees. This master thesis will answer the question on how to, for small engine, simulate the load that occurs during normal use of the engine and how to develop a dynamometer suitable for Husqvarna’s needs? The focus when developing the dynamometer will lie on solving the problem with minus degrees and having a good detachable coupling between the dyno and the chainsaw. The result is a hydraulic oil dynamometer. A hydraulic pump is attached to the guide bar and chainsaw using a detachable key way coupling and bearings. By controlling restriction of the flow in the hydraulic system the load can be controlled and also ultimately the RPM of the chainsaw. The hydraulic oil works fine in the minus degree as long as the right oil with the right viscosity range is used although a problem with the small chainsaws are that they are not reaching the full RPM in -25 °C. Mainly because of the backpressure created by the components in the system. This can be solved by minimizing the hydraulic systems total flow restriction. However this problem doesn’t affect the testing methods as long as the chainsaw easily can be disconnected and freed from the dynamometer and then be run to full RPM which the coupling between the pump and chainsaw enables. Engine Test Small Engine Husqvarna Chainsaw Subzero Temperatures
6	Learning approaches for the early detection of kickback in chainsaws Arnold, Drew D. 27 November 2012 (has links) Among the many safety hazards facing chainsaw operators, the phenomenon known as kickback is the most dangerous. Kickback occurs when the chain at the tip of the chainsaw is caused to stop abruptly, and transfers the energy of the cutting chain to motion of the saw. The saw will rotate backward toward the operator rapidly. The limited amount of published research on the topic of chainsaw kickback was conducted to develop standardized testing for consumer chainsaws. Modern chainsaws are equipped with safety measures such as low-kickback cutting chains and hand-guard braking mechanisms. These mechanisms have greatly improved the safety of chainsaws, but their inherent mechanical simplicity leaves room for improvement. The current work presents the research that analyzed the possible methods for detecting kickback electronically. Phase 1 of this work utilized a set of two accelerometers and a single gyroscope to determine if it is possible to distinguish a kickback event from normal cutting operations. A method for applying weighting coefficients to the three sensor readings, then summing the three signal values was optimized to obtain the greatest margin between kickback and normal cutting. The result of this study was that kickback is most easily identified by using only a gyroscope and setting a threshold. Phase 2 focused on detecting kickback as early as possible. Three methods were attempted: Signal Differentiation, a Simplified Bag of Words method, and applying a Support Vector Machine with selective undersampling and a stack of classifier vectors. Signal differentiation, while detecting the kickback events earlier, also suffered from many false positives. The Bag of Words method was unsuccessful in creating results different than the threshold method from Phase 1. The Support Vector Machine classification was able to detect kickback an average of 19.4 ms before the simple threshold method with no occurrence of either false positives or false negatives. This method is the most reliable and provides the greatest likelihood of detecting kickback early. / Graduation Date: 2013 Chainsaw Kickback Gyroscope Chain saws -- Safety measures Gyroscopic instruments
7	Development of an analytical model of the safety brake system for a chainsaw Olsson, Martin, Låstberg, Walter January 2018 (has links) The safety braking system with the hand guard is the most important safety equipment for the user of a chainsaw. The safety system prevents serious injuries caused by a kickback. A kickback is when the running chain suddenly gets stuck e.g. by getting stuck in wood or hit a rock. Due to the potentially serious consequences of a kickback, the braking system has to fulfil strict requirements formulated by the authorities. In the present thesis, a generic analytical model of the braking system for a typical Husqvarna chainsaw is developed. The model is implemented as an Excel work sheet, which will facilitate future projects. The thesis includes sections of analytical calculations with information provided from both Catia and resources at Husqvarna. Several experiments were accomplished to strengthen and prove the analysis. The torque, index and activation force are tested. The static activation force is then completed in a simulation program to provide spread in the model. The parameters with most impact are also detected in the Excel simulation. A matrix of testing is constructed with parameters outside the tolerances for the dynamic experiment. Due to the collected data of the test, the relation between the two types of activation can be established. In comparison between samples of production with the simulation on equal numbers of 24 tests gave adifference on 4.75 % in mean value. 6 out of 32 tests could not be approved within the authorities’requirements for the acceleration with respect to the higher tolerances than production in the testing matrix. The most significant parameters for the static force were the brake spring and the angle of the knee joint. For the dynamic activation, the dimensions of the knee joint is crucial. Reasoning for errors are implemented in the discussion section e.g. the importance of data for the band. To improve the accuracy of the model a section of future work contains suggestments. One suggestion for improvement is to deliver more production values to ensure the comprehension of the experiments. Husqvarna chainsaw band brake components Mechanical Engineering Maskinteknik
8	Detection of lubrication and chain tension in chainsaws using acoustic emissions Aldea, Madalina-Iolanda, Pettersson, Kristoffer January 2022 (has links) The lubrication and tension levels are two important parameters when running a chainsaw, both impacting the cutting performance and lifespan of the tool. An appropriate level of lubrication and tension leads to maximum performance of the chainsaw and direct benefits for the end-user. This thesis addresses the problem of detecting the lubrication status and the tension level using the information contained in the acoustic emissions captured in the guidebar of the chainsaw. Data was collected by running controlled experiments using an acoustic emissions sensor.Information was extracted from acoustic emissions by using a number of features computed on different frequency ranges.Three machine learning models were trained and evaluated on data corresponding to different combinations of lubrication status and tension levels. The models' performances were evaluated using the well-known metrics accuracy, precision, and recall. A pattern was found for each lubrication and tension setup, and the model that registered the highest performance was the Random Forest. The impact of temperature, guidebar, and chain on acoustic emissions is also analyzed. The detection of different lubrication levels using the information contained by acoustic signals is also addressed, the patterns in data being determined by computing features in the time and frequency domains. The analysis shows that the temperature does not have an impact when the running time is less than 10 minutes, and the chain has a bigger impact than the guidebar for the specific setup of the experiments. Moreover, a pattern dependent on the guidebar and chain combination correlated with the lubrication level was identified. The main contribution of this thesis consists of detecting a pattern representative of lubrication and tension setup in acoustic emission using a number of features computed in different frequency ranges. acoustic emissions artificial intelligence chainsaw lubrication machine learning Computer Systems Datorsystem
9	Six-Bullets Faith Lazor, Justin Ryan 02 June 2022 (has links) No description available. American Literature Ancient Languages Animals Astrophysics Bible
10	Stereotyper och Traditionell Könsrepresentation : En semiotisk analys angående final girl stereotypen i The Texas Chain Saw Massacre / Stereotypes and Traditional Gender Representation : A semiotic analysis regarding the final girl stereotype in The Texas Chain Saw Massacre Söderholm Mogensen, Hugo January 2022 (has links) Denna uppsats har skapats med syftet att undersöka och jämföra skildringen av stereotypen the final girl i filmerna The Texas Chain Saw Massacre (1974) och The Texas Chainsaw Massacre (2003), med utgångspunkt i teori om genusrepresentation och slasherfilmstereotyper. För detta använde undersökningen en komparativ metod i form av en filmsemiotisk analys. Metoden utformades också för att särskilt avläsa karaktärers beteende och agerande. För att stärka undersökningen har analys – och resultatdelen grundats på teori om stereotyper, slasherfilmer, och genusrepresentation, med särskild hänvisning till Carol J. Clovers uppsats: Her Body, Himself (1987). Undersökningens resultat påvisade att filmernas skildring och representation av stereotypen hanteras olika, där den senare nämna filmen skildras som mer stereotypisk enligt sin representation. Detta kan ha berott på det stora tidsspannet mellan filmerna, och de feministiska rörelser som har påverkat filmindustrin under denna tid. / The purpose of this essay was to examine and compare the portrayal of the final girl stereotype in The Texas Chain Saw Massacre (1974) and The Texas Chainsaw Massacre (2003), based on literature about gender representation and slasher movie stereotypes. To achieve the purpose of the study, a comparative method was used in the form of a film semiotic analysis. This method was also purposefully adjusted for analyzing the representation of a character’s manners and behavior. To strengthen the analysis, theoretical approaches about stereotypes, slasher movies, and gender representation was used, with special reference to Carol J. Clovers essay: Her Body, Himself (1978). The result proved that the stereotype was portrayed differently in both movies, and that the latter mentioned one included a stronger and more obvious stereotypical representation. This outcome may have been affected by the large time-gap between the two movies, as well as the feminist movements that had influence on the movie industry during the time of their respective productions. Stereotypes Gender Semiotics Film Horror Texas Chainsaw Massacre Final Girl Gender Stereotypes Femininity Masculinity Gender Roles Feminism Slasher Stereotyper Genus Semiotik Film Skräck Texas Chainsaw Massacre Final Girl Könstereotyper Femininitet Maskulinitet Könsroller Feminism Slasher Humanities and the Arts Humaniora och konst

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