This master´s thesis solves design of a mobile crane for handling air aggregates and ejection seats. Handling crane provides lifting a maximum weight of 300 kg to a height of 4600 mm. Subject of the work is the choice of appropriate technical solutions, design of lifting mechanisms, supporting structures and accessories. The suitability of the solution is checked by strength analysis of individual units. Another task is to provide mobility equipment and control stability against overturning. The appendix includes protocols static analysis of the program Nexis32, drawing overall crane assembly and manufacturing drawings selected parts.

No description available.

No description available.

The purpose of this project is to create a light weight robotic version of an ant that can withstand great forces, trying to come close to the ant’s lifting technique as much as possible. This idea was chosen with inspiration from nature, especially from the obscure forces of an ant. These insects are proven to be able to lift and carry heavy loads, up to a thousand times their body weight. Various lifting technologies are used by several facilities today and therefore there is a need for improvements in this field. By trying to come close to an ant’s appearance and mimic certain ant movements, a hexapod was designed over a period of four months. The tests made in this project were divided into three categories; stability, lifting and gripping ability. The best balance was achieved by placing the legs’ contact points on the ground as far away from each other as possible. In total the robot ant could lift about 1.02 times its own weight and bear 3.01 times its own weight on the thorax. / Målet med projektet är att konstruera en lågvikts robotmyra som kan uthärda stora krafter och härma myrors rörelse vid lyft så mycket som möjligt. Projektidén valdes med inspiration från naturen, speciellt från de otroliga krafter hos en myra. Myror har bevisats kunna lyfta och bära tunga laster eller mer exakt tusen gånger sin egen vikt. Olika lyfttekniker används av flera faciliteter idag och därmed finns det behov av förbättringar i detta område. Genom att efterlikna en myras utseende och härma dess rörelser designades en sexfoting under en period på fyra månader. Testerna delades in i tre olika kategorier; stabilitet, lyft- och greppförmåga. Den bästa balansen uppnåddes då benens kontaktpunkter med marken placerades så långt ifrån varandra som möjligt. Totalt klarade robotmyran att lyfta 1.02 gånger sin egen vikt och bära 3.01 gånger egna vikten på ryggen.

enlighet med Maskindirektiv (MD)2006/42/EG ska alla lyftredskap som tas i bruk eller omsätts på marknaden CE-märkas. Att ett lyftredskap är CE-märkt innebär att det uppfyller kraven det Europeiska ekonomiska samarbetsområdet (EES) har på hur säkert, hälsosamt och miljövänligt lyftredskapet är över hela sin livscykel. I dagsläget anlitar Hakfelt Produktion AB, fortsättningsvis Hakfelt, som är legotillverkare av plåtdetaljer externa certifieringsfirmor för att utföra CE-märkningen av deras egenproducerade lyftredskap. Arbetets syfte var att utarbeta en enkel, systematisk process för konstruktion av lyftredskap som dels uppfyllde Hakfelts krav och dels uppfyllde kraven för att kunna anbringa CE-märket. Det skulle spara tid, resurser samt ge ökad kontroll över processen och därigenom möjlighet att förädla den för Hakfelt. Arbetets mål var en handbok för att konstruera och CE-märka lyftredskap. Arbetets delmål var att konstruera och CEmärka ett lyftredskap som skulle utgöra fundament och exempel för handboken. Vid konstruktion av det exemplifierande lyftredskapet användes nulägesanalys, kravspecifikationer och konceptgenerering för att finna tänkbara koncept. 3D-modeller och prototyper användes för att bestämma en primärkonstruktion. Teknisk dokumentation, riskbedömning och hållfasthetsanalyser utfördes för att bevisa överensstämmelse med rådande standard. Från metoderna utarbetades mallar och tillvägagångssätt som sammanställdes till en handbok. Arbetets resultat, handboken, bedömdes vara till hjälp och överlämnades till Hakfelt Produktion AB. Lyftredskapet tillverkades, CE-märktes och används i dagsläget. Effekten av arbetet har inte kunnat plockats hem inom ramarna för detta arbete. Frågetecken kvarstår kring om Hakfelt Produktion AB faktiskt skulle spara tid och resurser genom att följa handboken och utföra CEmärkningen internt. Fortsatt arbete krävs för implementering av handboken, alternativt förfining av den genom att utse en processägare, för att kunna fastslå om handboken leder till den önskade resurseffektiviseringen. / In accordance with the Directive of Machinery (MD) 2006/42 / EC, all lifting equipment that is put into use or placed on the market must be CE marked. A CE-marked lifting equipment means that it meets the requirements of the European Economic Area (EEA) on how safe, healthy and environmentally friendly the lifting equipment is throughout its lifecycle. At the present, Hakfelt Produktion AB, hereinafter Hakfelt, which is a subcontractor of sheet metal parts, enlists external certification companies to carry out the CE-marking of their self-produced lifting equipment. The purpose of this thesis was to develop a simple, systematic process for the construction of lifting equipment that met both Hakfelt's requirements and the requirements for CE-marking. This would save time, resources and provide increased control over the process and thereby the opportunity to refine it for Hakfelt. The goal of this thesis was a handbook for designing and CE-marking lifting equipment. The subgoal of this thesis was to design and CE-mark a lifting tool that would act as foundation and example for the handbook. In the design of the exemplary lifting tool situation analysis, specifications of requirements and concept generation-methods were used to find possible solutions. 3D models and prototypes were used to combine solutions and determine a primary design. Technical documentation, risk assessment and strength analyses were generated and performed to prove compliance with current standards. From the methods used, templates and approaches were developed and compiled into a handbook. The results of the work, the handbook, was deemed to be of help and handed over to Hakfelt Produktion AB. The lifting equipment was manufactured, CE-marked and is currently used. The effect of this thesis and the resulting handbook has not been proven within the framework of this work. Question marks remain as to whether Hakfelt Produktion AB would actually save time and resources by following the manual and carrying out the CE-marking internally. Further work is required for the implementation of the handbook, or alternatively refinement of it by appointing a process owner, in order to then be able to determine whether the handbook leads to the desired resource efficiency. / <p>2022-07-01</p>

Travis, SK, Pritchard, HJ, Mujika, I, Gentles, JA, Stone, MH, and Bazyler, CD. Characterizing the tapering practices of United States and Canadian raw powerlifters. J Strength Cond Res 35(12S): S26-S35, 2021-The purpose of this study was to characterize the tapering practices used by North American powerlifters. A total of 364 powerlifters completed a 41-item survey encompassing demographics, general training, general tapering, and specific tapering practices. Nonparametric statistics were used to assess sex (male and female), competition level (regional/provincial, national, and international), and competition lift (squat, bench press, and deadlift). The highest training volume most frequently took place 5-8 weeks before competition, whereas the highest training intensity was completed 2 weeks before competition. A step taper was primarily used over 7-10 days while decreasing the training volume by 41-50% with varied intensity. The final heavy (>85% 1 repetition maximum [1RM]) back squat and deadlift sessions were completed 7-10 days before competition, whereas the final heavy bench press session was completed <7 days before competition. Final heavy lifts were completed at 90.0-92.5% 1RM but reduced to 75-80% 1RM for back squat and bench press and 70-75% for deadlift during the final training session of each lift. Set and repetition schemes during the taper varied between lifts with most frequent reports of 3 × 2, 3 × 3, and 3 × 1 for back squat, bench press, and deadlift, respectively. Training cessation durations before competition varied between deadlift (5.8 ± 2.5 days), back squat (4.1 ± 1.9 days), and bench press (3.9 ± 1.8 days). Complete training cessation was implemented 2.8 ± 1.1 days before competition and varied between sex and competition level. These findings provide novel insights into the tapering practices of North American powerlifters and can be used to inform powerlifting coaches and athlete's tapering decisions.

Offshore floating wind turbines represent the future of wind energy. However, significant challenges must be overcome before these systems can be widely used. Because of the dynamics of offshore floating wind turbines -- surge, sway, heave, roll, pitch, and yaw -- and the resulting interactions between the rotor and generated wake, the aerodynamic analysis methods and design codes that have found wide use throughout the wind energy industry may be inadequate. Application of these techniques to offshore floating wind turbine aerodynamics may result in off-optimal designs, effectively handicapping these next-generation systems, thereby minimizing their full potential. This dissertation will demonstrate that the aerodynamics of offshore floating wind turbines are sufficiently different from conventional offshore and onshore wind turbines, warranting the use of higher fidelity analysis approaches. It will outline the development and validation of a free vortex wake code, the Wake Induced Dynamics Simulator, or WInDS, which uses a more physically realistic Lagrangian approach to modeling complex rotor-wake interactions. Finally, results from WInDS simulations of various offshore floating wind turbines under different load conditions will be presented. The simulation results indicate that offshore floating wind turbine aerodynamics are more complex than conventional offshore or onshore wind turbines and require higher fidelity analysis approaches to model adequately. Additionally, platform pitching modes appear to drive the most aerodynamically-significant motions, followed by yawing modes. Momentum balance approaches are shown to be unable to accurately model these dynamic systems, and the associated dynamic inflow methods respond to velocity changes at the rotor incorrectly. Future offshore floating wind turbine designs should strive to either minimize platform motions or be complementarily optimized, via higher fidelity aerodynamic analysis techniques, to account for them. It is believed that this dissertation is the first in-depth study of offshore floating wind turbine aerodynamics and the applicability of various analysis methods.

En vindtunnel används för att simulera luftflödet som verkar på till exempel en nerskalad modell av en verklig flygplansvinge eller ett fordon. Detta hjälper att förstå och ta fram de komponenter som påverkar interaktionen samt krafter och moment.  Mittuniversitetets laboratorium är i behov av en ny kraftsensors-rigg, detta är en rigg som mäter krafter som påverkar på en vinge profil inuti en vindtunnel. En vidareutveckling av den befintliga kraftsensors-riggen skulle innebära en alltför lång arbetsprocess, därför bestämdes det att utvecklas en ny design av sensor-riggen som löser några felkällor som den tidigare sensor- riggen har; vilka är inexakta mätvärde samt att den befintliga riggen mäter enbart lyftkraften. Genom framtagning av en ny kraftsensors-rigg som går att tillverka i Mittuniversitetets lokaler minskar tiden för att utföra vindtunnel tester samt ökar mätvärdenas noggrannhet. Syftet med detta arbete har varit att ta fram konstruktion av en ny kraftsensors-rigg som kan mäta krafter i x- och y-axeln det vill säga lyft och dragkraft. Kraftsensors-riggen kommer att installeras i vindtunneln som finns i Mittuniversitets laboratorium.  I detta projekt följs det designprocessens arbetsgång som är uppdelat i fyra faser. Den första fasen, förstudiefasen, definierades produktens kravspecifikation och funktionsanalys. Den andra fasen, kreativa fasen, inleddes med brainstorming för att generera konceptlösnings idéer. Sedan används Pugh-matrisen i konceptutvärdering- och framtagningsfasen för att utvärdera och välja konceptet utifrån en kvantitativ-metod. Sedan modellerades en tredimensionell modell för det färdiga konceptet med hjälp av CAD. Slutligen i konstruktion-utvecklingsfasen framställdes konstruktionen med hjälp av CAD:s modeller. därefter skrevs de komplexa delarna ut med en 3D-utskrivare samtidigt som de mindre komplexa delar framställdes av trä med en laser skärare för att spara på material samt kostnader, till slut byggdes och testades riggen i Mittuniversitets verkstad.  Projektet resulterade i en kraftsensors-rigg som kan mäta både luftmotstånd-och lyftkraften i en låg hastighet vindtunnel med noggrannare mätvärde än den tidigare riggen. / A wind tunnel is used to simulate the air flow that acts on, for example, a scaled-down model of a real aircraft wing or a vehicle. Which allows a better understanding of the components that affect the interactions between the air and the object of study, that is to say the forces and torque affecting the object. In order to fully utilize the wind tunnel in the laboratory at Mid Sweden, it has proved necessary to design a new wind tunnel force balance, which is a structure that measures forces affecting objects inside the wind tunnel. The reason being is that the current force balance sensor has some issues concerning accuracy of measurement and the lack of measuring other forces than lifting forces. A further development of the existing force balance would involve too long a work process, so it was decided to develop a new design of a wind tunnel force balance that solves some sources of error that the previous design of the force balance has and introduce an air resistance measurement component. By developing a new force balance that can be manufactured in Mid Sweden University's premises, the time for performing wind tunnel testing is reduced and the accuracy of the measured values is increased. The purpose of this project has been to develop a construction of a new force balance that can measure forces in the x- and y-axis, meaning lifting and air resistance. The force balance will be installed in the wind tunnel located in Mid Sweden University's laboratory.  In this project, the workflow of the design process is followed, which is divided into four phases. The first phase, the research phase, defined the product's requirements specification and functional analysis. The second phase, concept development and control art, began with brainstorming to generate concept solution ideas. The Pugh matrix was then used in the prototyping and validation phase to evaluate and select the concept based on a quantitative method. Then a three-dimensional model for the finalized concept was modelled using CAD. Finally, in the testing and refining phase, the design was produced using the CAD models. Then the complex components were printed with a 3D-printer while the less complex component were made of wood using a laser cutter to save on materials and costs, finally the rig was built and tested in Mid Sweden University's workshop.  The project resulted in a force balance that can measure both air resistance and lifting force in a low-speed wind tunnel with a more accurate measurements than the previous force balance.

No description available.

In the thesis, a lifting body has been designed aiming to generate lift force for the pentacopter,called TILT LR (Long Range), at higher velocities during flights to improve the aerodynamicperformances. The configuration, which is used as the skeleton of the long range drone for upto 75 kilometers flights, is based upon a tilting system allowing the rotors to rotate around theirown axis in both pitch and roll angles. This offers the possibility to the TILT LR flying withoutany vertical excess thrust at a proper angle of attack and velocity. This new drone can be directlyapplied to missions require long flight time or cover long distance, such as Search &amp; Rescue(SAR), power lines and off-shore structures inspection, fire monitoring or surveillance.Several main CAD models have been created during the process of design and presented in thereport together with the final design. For each model in the process, CFD simulations have beenapplied to observe the behaviors of the flows around the surfaces of the body during steadyflights, followed by a brief analysis for further modification. A series of simulations withvarying velocities and angle of attack have been performed for the final design, analyzing itsperformances under different air conditions. Flight envelope of the design has been presentedalso, together with some ideas of possible further studies on the pentacopter.