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A simulation tool for flight dynamics and control investigations of three different Vertical Take Off and Landing (VTOL) unmanned aircraft configurations has been developed. A control concept has been proposed in order to take advantage of the fast response characteristics of the ordinary small engine/propeller propulsion systems in such aircraft, as well as replacing the complex rotors used previously in VTOL concepts for small unmanned aircraft. The simulation model has been established on the basis of the proposed concept so that it can also be used to study the feasibility of this idea. An Object-based methodology has been introduced so as to reduce the amount of aerodynamic required data for the simulation model. The equations of motion associated with the aircraft multibody system with ten degrees of freedom have been derived using the Newton-Euler method. The modelling of various subsystems including the propeller model, the airframe aerodynamics and the engine model has been carried out. A method for calculating the propellers' slipstream effects on the other components has been presented. Input data for the simulation model have been estimated, using different sources. The Advanced Continuous Simulation Language (ACSL) has been used for the programming of the mathematical model. A series of comprehensive tests have been carried out in order to demonstrate the validity of the simulation model. The ability of the simulation model to explain the aircraft modes of motion as well as to discover unknown nonlinear behaviours and to describe them has been demonstrated.

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The aim of this study was to determine how the performance of the Egyptian high jumpers is depending on the kinematic parameters of a take-off phase. The sample of the study has been selected from competitors of the high jump event - three jumpers representing the Egyptian international athletic team. The researcher has studied the sample using a direct measurement by a synchronized 3D video system to measure the kinematic parameters. The researcher has found a relation between record level and vertical velocity components with improvement in technique and better fitness levels, thus the Egyptian jumpers can achieve further progress in their results. This raises optimism because Omer Samir (A2) is very young and his current record 2.02m gives hope for future World - Class. Key words High jump, kinematic parameters, take-off phase.

The aim of this study was to determine how the performance of the Egyptian high jumpers is depending on the kinematic parameters of a take-off phase. The sample of the study has been selected from competitors of the high jump event - three jumpers representing the Egyptian international athletic team. The researcher has studied the sample using a direct measurement by a synchronized 3D video system to measure the kinematic parameters. The researcher has found a relation between record level and vertical velocity components with improvement in technique and better fitness levels, thus the Egyptian jumpers can achieve further progress in their results. This raises optimism because Omer Samir (A2) is very young and his current record 2.02m gives hope for future World - Class. Key words High jump, kinematic parameters, take-off phase.

The aerials event of freestyle skiing is a relatively new discipline having only been introduced into the Olympic Games as a medal event in 1994. The purpose of this study was to develop a simulation model for the takeoff phase of aerials, with the intention of learning more about how the requisite linear and angular velocities at takeoff are generated. Experimental data was collected for six triple somersaulting aerial jumps. The jumps were filmed with four high-speed video cameras and a total of 17 points were manually digitised for each camera view of each jump. The digitised coordinates were reconstructed using a three dimensional direct linear transformation (3D-DLT) and processed using a film program written in FORTRAN. The program produced kinematic data for the takeoff phase of the six jumps. A simulation model for takeoff was developed, comprising of a rod (body) and a ski. At the connection between the rod and the ski is a passive torque, governed by the stiffness coefficient K. Experimental values for the height of the centre of mass (CoM), moment of inertia (MoI), initial linear velocity (VG) and initial angular velocity (ωpg) were used as model inputs. A combined drag and air resistance coefficient (D) was varied with K to match the experimental VG and ωpg at takeoff, resulting in an average difference of -0.07% for VG, and -16.10% for ωpg. A straight body simulation was run, eliminating the effect of joint angle changes on CoM height and MoI, it was found that a straight body matches the experimental data just as well as a simulation using joint angles. This result suggests that joint angles changes play a different role, other than to generate angular and linear velocity. Further alterations were made to the model parameters; K was varied, which increased the angle of the CoM behind the normal to the skis (ψ) as K increased. Initial angular velocity was varied with results suggesting that a forwards leaning motion at the start of the kicker generated a larger angular velocity at takeoff. An additional ankle torque was implemented for the final 0.1s of takeoff, this increased ωpg and reduced the difference to just -3.01%. Conclusions were drawn that the passive torque of the skis and an additional ankle torque prior to takeoff play a large role in governing takeoff conditions.

För att utöka ett fordons användningsområde kan det utrustas med olika typer av arbetsredskap och lasthanteringsutrustning. För att driva dessa finns möjlighet till kraftuttag (PTO - Power Take-Off) från ett antal anslutningar vid motor och drivlina. I dagsläget saknar motorns styrsystem information om dessa laster vilket kan påverka styrningen negativt. I detta arbete presenteras en metod för att estimera det okända lastmomentet på kraftuttaget. Metoden utgår från Newtons andra lag för svänghjulet och det drivande momentet till drivlinan beskrivs av en dynamisk modell. Genom att beräkna hur mycket moment som borde krävas vid aktuellt körfall och jämföra detta med det moment som motorn levererar kan parasitförluster och okända externa laster estimeras. En känslighetsanalys av omgivningens inverkan på modellen och PTO-estimeringen visar att estimeringen i dagsläget inte går att utföra på ett robust och tillförlitligt sätt. De fel som uppstår till följd av bristfällig information om bland annat väglutning och fordonsmassa ger upphov till fel i PTO-estimeringen som är vida större än de lastmoment som ska estimeras. Vidare konstateras att värdet på det levererade motormomentet i motorstyrsystemet (EMS) kan ha ett statiskt fel på upp till cirka 70Nm. / To extend the possible use of a truck it can be equipped with auxillary equipment for handling cargo and different working tools. These are powered using a Power Take-Off (PTO) connected to the vehicle´s drivetrain. In the current situation the control system lacks information about these loads, which can have a negative impact on the control. In this thesis a method for estimating the unknown PTO torque is presented. The method is based on Newtons second law of motion describing the motion of the flywheel. The driving torque from the drivetrain is described by a dynamic model. By calculating how much torque that should suffice in the present driving situation and comparing this to the torque delivered by the engine, the parasitic losses and unknown external loads can be estimated. A sensitivity analysis of the ambient influence on the model and the PTO estimation shows that the estimation cannot be performed in a robust and reliable way. The errors that arise from faulty input to the model such as deficient road slope and vehicle mass information result in errors with greater magnitude than the load torque to be estimated. It is also concluded that in the Engine Management System (EMS), the calculation of the torque delivered by the engine can show a static error of up to approximately 70Nm.

No description available.

Thesis (M.S.)--California Polytechnic State University, 2008. / Mode of access: Internet. Title from PDF title page; viewed on March 17, 2009. Major professor: David D. Marshall. "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree of Master of Science in Aerospace Engineering." "June 2008." Includes bibliographical references (p. 126-127). Also available on microfiche.

Thesis (Ph. D.)--Aerospace Engineering, Georgia Institute of Technology, 2007. / Dimitri N. Mavris, Committee Chair ; Lakshmi N. Sankar, Committee Member ; Daniel P. Schrage, Committee Member ; Robert J. Englar, Committee Member ; Robert C. Michelson, Committee Member.