The background to this study is that the forest company, Holmen, has found large discrepancies between harvested volume and the measured volume at the industry. Factors like bark features, breakage, double tops, bends and stem damages was noted, and all stems were measured manually. Hypothesis testing with the method "random in pairs" were used to examine whether the harvester measured values significantly differed from the manually measured. The result of a properly calibrated harvester shows in average underestimation of the volume with Skogforsk Pine as a bark function. This means that the harvester isn´t the reason why the volume measured in the industry is lower, the fault is elsewhere. The study also indicates a need for a unique bark function for logepole pine..

Bergkvist Insjön AB är ett familjeägt företag som äger och driver ett sågverk i Insjön. Flödet av timmer in till sågverket består både av tall och gran. Av grantimret utgörs en relativt liten del av långt timmer, 6,10 meter, vilket upptar plats i timmersortering och på timmerplan. Ett alternativ kan vara att satsa på andra längder. Syftet med detta arbete är att göra en ekonomisk utvärdering av sortimentet 6,10 meters grantimmer.

In this study we have examined the possible quality standards and methods for applications with service workshops in the forest industry. The purpose of the methods presented here was to start the work of standarardising the maintenance service in the industry and be of use for service providers in their quality effort.The methods we used to accomplish the study were interviews and field visits together with a comprehensive literature research. Our results are presented in the form of four solution proposals: a standard based on existing SIS standards for terminology and key indicators, checklists that are filled in by mechanics with customer participation, the construction of a instructions database, and the implementation of the method 5s.We believe our suggestions can help the service providers in the four problem areas that we have identified: long term strategy, documentation, recruitment of competent technicians, and standard procedures in their operations. These improvements will be beneficial for both the service provider and the customer..

This report is a thesis work for a B.Sc. in Forestry exam at the School for Forest Engineers, SLU. The aim of the work was to compare fuel consumption during work in practical field conditions with a standardized method developed by Skogforsk (The Forestry Research Institute of Sweden), (Brunberg, 2005) for harvesters and forwarders from different manufacturers and of different sizes in order to promote the development of more fuel efficient machines. Two studies were carried out. - Statistics of fuel consumption were collected. - An inquiry was sent out in order to get more detailed information of different aspects influencing the fuel consumption. The studied machines were divided into two classes, large machines (> 150 kW), and average size machines (100 ? 150 kW), and of the manufacturer Timberjack and Valmet. Our results shows a 15 % lower fuel consumption for average size harvesters and an 8 % higher fuel consumption for large harvesters compared with Skogforsks model.

This is a thesis report from SLU in Skinnskatteberg, the Swedish university of agricultural sciences. This study is an evaluation of a course in attitudes and behavior for participants of the ETT- project led by Skogforsk, the forestry research institute of Sweden. They do research for the benefit of Swedish forestry. The ETT-project is a project where there are both 74 tons ST-trucks and 90 tons ETT-trucks in test on the public roads. This study is concentrated on the ST-trucks and their drivers, company owners and logistics managers. The evaluation is done by interviews with the various participants.

In this study, pollen contamination (measured by the number of seeds pollinated by pollen not belonging to any of the clones on the seed orchard) is compared between open pollination and isolated pollination environments in a Scots pine (Pinus sylvestris) seed orchard called Västerhus, located outside Önsköldsvik. In this seed orchard a tent experiment is taking place. Skogforsk has built six large tents covering 12-14 trees with each tent. Fertilization patterns were compared between one tree in a tent with a supplementation of pollen from five clones not represented in the tent and another tree of the same clone subject to open pollination outside the tents. By using DNA markers the paternity was determined for 48 seeds from each tree.

In this study, pollen contamination (measured by the number of seeds pollinated by pollen not belonging to any of the clones on the seed orchard) is compared between open pollination and isolated pollination environments in a Scots pine (Pinus sylvestris) seed orchard called Västerhus, located outside Önsköldsvik. In this seed orchard a tent experiment is taking place. Skogforsk has built six large tents covering 12-14 trees with each tent. Fertilization patterns were compared between one tree in a tent with a supplementation of pollen from five clones not represented in the tent and another tree of the same clone subject to open pollination outside the tents. By using DNA markers the paternity was determined for 48 seeds from each tree.

Syftet med studien var att utvärdera om kranspetsstyrning i skogsmaskiner är ett enklare styrsystem att lära sig från grunden och om arbetsbelastningen värderades lägre, än den konventionella styrningen. Meningen var även att kartlägga skillnader i inlärningsprocessen samt i upplevd arbetsbelastning. Detta krävde konstruktion av mätmetoder för insamling av relevant information. Utvärderingen gjordes i enskogsmaskinsimulator vid manövrering av skotare samt genom enkätundersökningar. Studien genomfördes med hjälp av försöksdeltagare från naturbruksgymnasiet Jällaskolan i Uppsala.

Södras maskinentreprenörer följer i dagsläget upp utvalda bestånd med linjetaxering men i framtiden finns förhoppningar om att gallringsuppföljningen ska ske i realtid i skördardatorn. Skogforsk bedriver för närvarande ett projekt om automatisk gallringsuppföljning där Södra är delaktiga. Studien gick ut på att utreda om beståndets grundyta före gallring kan skattas utifrån stickvägsuttaget. Skördarförarna klassade sin egen stickvägsutläggning för att få fram en bedömd slingerkoefficient. Slingerkoefficienten är en kvot som beskriver hur grundytan i stickvägarna förhåller sig till den genomsnittliga grundytan i beståndet före gallring. Vid gallring av de utvalda försöksbestånden skiljdes skördade stammar i stickvägarna från stammar uttagna från mellanzonen. För att få information om bestånden före gallring totalklavades bestånden direkt efter gallring och sedan adderades klavdata samman med data om uttagna träd.

The predominant forestry harvesting method is based on the harvester-forwarder method, theharvester folds, branches and cuts trees, and sorts the logs into piles, while a forwarder transportsthe logs to a landing area.This master thesis work is about realization of a dynamic forwarder simulation model, and itspurpose is to provide an integrated forwarder simulation model in MATLAB/SimMechanicswhere the forwarder is based on a concept using pendulum arms to connect wheels and chassis.Active suspension control is developed and implemented into the simulation model, and finallycompared in simulation with passive suspension.In a first step, an integrated forwarder simulation model is developed, containing a simplifiedforwarder model, a tire-to-ground interaction model and a test track model. The simplifiedforwarder model is based a rigid multi-body system with a spring-damper suspension of thependulum arms. The tire-to-ground interaction model calculates the reaction forces, friction fromthe ground and applies the propulsion force. The test track model is a simplified version of thereal test track in Skogforsk. The propulsion wheel torque control is used to regulate theforwarder speed.

Syftet med denna studie var att utreda hur röststyrning kan användas för kontroll av aggregatet på en engreppsskördare. För att studera röststyrning genomfördes en så kallad Wizard of Oz-studie. Metoden går ut på att en människa ersätter en funktion i ett system som ännu inte finns eller är färdigutvecklad. I studien var det röstigenkänningen och inmatningen av korrekt respons som utfördes av en människa, trollkarlen. Rollen som trollkarl utfördes av en före detta skördarförare som numera arbetar som forskare på Skogforsk. Studien genomfördes i Skogforsks skogsmaskinsimulator. I den kan en försöksperson på ett verklighetstroget sätt arbeta med en engreppsskördare.

Over the past few years the Swedish forestry industry has become increasing interested in direct seeding. Although, in practice, this interest has been restricted to pine seed, the knowledge and techniques that have been developed for pine seeding can readily be transferred to spruce. Direct seeding is a method that is of interest to the forestry industry since it can lead to lower regeneration costs, denser stands and better root development than the more conventional planting method. This study evaluated experiments that focused on direct seeding of spruce in the northern Sweden. Skogforsk set-up the experiments in Gideå and Sävar in 2003.

This thesis is made on behalf of SCA's Forestry Division and is a comparison of two bucking simulation tools: Aptan (manufactured by Skogforsk) and Best/upr (from Berget Systemdesign). The data is based on 32 stands from SCA's forests in Norrbotten and Västerbotten. The objective is to compare the simulations created by the tools with the harvested volumes from those stands. Three variables are needed for the bucking simulation; these are the diameter distribution (at breast height), the relationship function between diameter and height, and the taper coefficients. The volumes of five different assortments from the stands are compared.

Arbetet som skogsmaskinförare är mycket belastande både fysiskt och mentalt. För att minska arbetsskador och sjukskrivningar, vilket i längden kan leda till brist på förare och svårigheter att rekrytera nya, behöver arbetsbelastningen minskas. Genom att automatisera vissa delar av skördarförarens arbete kan vinster avseende både den fysiska och mentala belastningen göras. Detta genom att föraren får mer tid att ta de många beslut som ingår i arbetet medan maskinen tar över enkla, upprepade handlingar. Därmed minskar också reglageanvändningen och det ges fler möjligheter till mikropauser då musklerna kan återhämta sig.Målet med examensarbetet var att genom studier av kommunikationen mellan människa och maskin komma med förslag på hur belastningsproblemen kan lindras.

Det finns ett behov av hjälpmedel i skogsbranschen som underlättar det dagliga beslutstagandet som personalen ställs inför. Detta kan vara datamodeller som simulerar och optimerar olika beslutstaganden på beståndsnivå eller på skogsinnehavsnivå. Inom ramen för detta arbete programmerades ett kalkylstöd i Microsoft Excel med verktyget Visual Basic ©. Kalkylstödet kopplades samman med den av Skogforsk publicerade produktionsmodellen ProdMod (Ekö 1985) via makron. Med dessa två program kan beståndsutveckling och åtgärder simuleras på beståndsnivå med tillväxt, avverkningsuttag samt avverkningskostnad och intäkter som utdata.