Thesis (M.S. in Operations Research)--Naval Postgraduate School, March 2010. / Thesis Advisor(s): Chung, Timothy H. Second Reader: Johnson, Rachel T. "March 2010." Description based on title screen as viewed on April 27, 2010. Author(s) subject terms: Situational awareness, surveillance, interdiction, Vehicle-Borne Improvised Explosive Devices (VBIED), cross-validation, design of experiments, experimental design. Includes bibliographical references (p. 61-62). Also available in print.

Made available in DSpace on 2014-06-11T19:28:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-01Bitstream added on 2014-06-13T19:37:20Z : No. of bitstreams: 1 akiyama_mk_me_guara.pdf: 2877437 bytes, checksum: f64beca66421f23a46b9c0d6fe1c82e0 (MD5) / Universidade Estadual Paulista (UNESP) / Neste trabalho é feito um estudo de comportamento dinâmico de um veículo pequeno com suspensão passiva trafegando em pista com ondulações regulares, e análise da estabilidade. O veículo é modelado considerando-o como um sistema multicorpo rígido, com sete graus de liberdade, utilizando-se o método de Kane. As equações do movimento são definidas sobre uma listagem de programa preparada segundo o programa AUTOLEV, o qual emite um programa em linguagem FORTRAN para as simulações. Foi necessário obter-se diretamente do veículo dados característicos como: centros de gravidade, coeficientes de rigidez dos pneus e das molas, e coeficientes de amortecimento para a realização das simulações. Além disso, foram definidos dois tipos de rugosidade, quatro velocidades, duas seqüências de rugosidade, sendo uma com cinco ondas e outra com vinte ondas, bem como a consideração do veículo com um ocupante e cinco ocupantes. Com os resultados do processamento dos dados, foram traçados gráficos e realizadas análises dos efeitos das rugosidades sobre a dinâmica do veículo, conclusões e apresentações de sugestões. / In this paper we study the dynamic behaviour of a small vehicle provided with passive suspension, riding on regularly rugged roads, and stability analysis. The vehicle is modelled considering as a rigid multibody system, with seven degrees of freedom, applying the Kaneþs method. Motion equations are defined on a program list according to the AUTOLEV software, which gives a FORTRAN language program for simulations. It was necessary to obtain directly from the vehicle, characteristic datas as centres of gravity, tires and springs stiffnesses, damper characteristics. In addition, it was defined two road roughnesses, four riding speeds, two sequences of roughness, one with five and other with twenty waves, as well as the consideration of vehicle with one and five occupants. With the results of processing, graphics were plotted, and analysis realized about roughness effects on vehicle dynamics and presentations of suggestions.

In an effort to increase the available capacity of a lead-acid battery, the effects of pulsed discharge currents as opposed to the effects of continuous discharge currents on the battery were investigated, for a wide range of frequency, mark/space ratio and peak current of the discharge waveform. It was found that for certain conditions of pulsed discharge, the use of pulsed currents can provide a considerable increase in available capacity when compared to that obtained from using conventional continuous currents. In order to increase the efficiency and reduce the time of the lead-acid battery charge, the effects of using pulsed charging currents with ·and without depolarisation discharge pulses interspersed throughout the charging period as opposed to using conventional continuous current charging was investigated. For the tests performed, it was found that pulsed current charging without depolarisation pulses offers no advantages over conventional continuous current charging for three-stage and single-stage charging techniques. The use of pulsed currents with depolarisation pulses was found to be less effective than using conventional continuous current or straight pulsed current charging. A model for the cell terminal voltage and state-of-charge of the battery is derived from the results of an extensive series of tests performed by the author. In this writing for the first time a model accurately accounts for the dependence of recuperation, regeneration and wide variations in the discharge rate on the temperature of the electrolyte and the effects of these factors on the terminal voltage and state-of-charge. Additionally, for the first time a comprehensive model for use with pulsed discharge currents is derived. The models were tested under dynamic conditions of battery operation and were found to be able to predict battery state to a high degree of accuracy, and were also found to be more accurate than existing models.

Designing a Kids Train body and Chassis, where Body of a train plays an important role as it should be attractive, fun, educational, comfortable and safer for the kids. and the chassis should be able to withstand sufficient load and able to accommodate steering, battery, seating, motor, axles and bumper at all sides which is developed for SB international AB.A literature study is carried out to review various designs body of train and chassis, latest innovations and advanced materials used to manufacture the same. The various types of forces and stresses commonly acting on chassis structures are analyzed and their effects on the vehicle is understood and different types of train design is studied in order to make an attractive train for the kids by using Waterfall method to understand the concepts in designing a Train body. The pro-con analysis is conducted to evaluate merits and demerits of each alternative type of body of a train and the material to manufacture it. The most essential  design criteria are derived from the QFD (Quality function deployment) which then acts as important guidelines during the actual design process.Structural chassis frame is designed as per the design criteria with little modification and designing a body of a train using the CAD software CATIAV5R20 and the structural stability of the same is tested and analyzed using Inspire (solid thinking) software.

This Master of Science Thesis focuses on the modeling of an automotive system. Several of the main automotive systems are combined to represent a full vehicle model. One system is a road plane model with degrees of freedom in yaw and lateral acceleration. The model at first includes a two dimensional representation of a steering system and then later expands the steering model to three dimensions. Also included is a five degree of freedom, two-dimensional multibody model in order to model the response of the chassis/suspension system due to an applied step steer input. The tire system incorporates the Magic Formula tire model. Furthermore, a graphic user interface is developed to facilitate setting up the initial conditions and inputs to the full vehicle model, and to ease the use of the simulation.

This thesis discusses a general approach to hybrid powertrain control based on optimisation and optimal control techniques. A typical strategy comprises a high level non-linear control for optimised energy efficiency, and a lower level Linear Quadratic Regulator (LQR) to track the high-level demand signals and minimise the first torsional vibration mode. The approach is demonstrated in simulation using a model of the Toyota Prius hybrid vehicle, and comparisons are made with a simpler control system which uses proportional integral (PI) control at the lower level. The powertrain of the Toyota Prius has a parallel configuration, comprising a motor, engine and generator connected via an epicyclic gear train. High level control is determined by a Power Efficient Controller (PE C) which dynamically varies the operating demands for the motor, engine and generator. The PEC is an integrated nonlinear controller based on an iterative downhill search strategy for optimising energy efficiency and battery state of charge criteria, and fully accounts for the non-linear nature of the various efficiency maps. The PEC demand signals are passed onto the LQR controller where a cost function balances the importance of deviations from these demands against an additional criterion relating to the amplitude of driveline vibrations. System non-linearity is again accounted for at the lower level through gain scheduling of the LQR controller. Controller performance is assessed. in simulation, the results being compared with a reference system that uses simple PI action to deliver low-level control. Consideration is also given to assessing performance against that of a more general, fully non-linear dynamic optimal controller.

No description available.

The research project 'Controllability of Road Vehicles at the Limits of Tyre Adhesion' (CROVLA) was established to investigate how tyre and chassis properties contribute to the handling characteristics and stability of vehicles operating at or near to the limit condition. The project involved the Department of Transport, SP Tyres UK Limited, Jaguar Cars and Cranfield University. An extensive proving ground test program of typical limit handling tests provided characteristic driver input and vehicle response data for a variety of vehicle configurations. The test data analysis was based on the concept of correlation. Cross- correlation coefficients and average response time delays were obtained for various pairs of quantities, namely steering angle and torque for the input and yaw rate and lateral acceleration for the response. The predictability of the vehicle response was evaluated by the rate by which the correlation coefficients change with severity. Analogous to the proving ground work, vehicle dynamics simulations were carried out. Two programs were employed to study the steady state performance and the transient limit handling behaviour. The 'Steady State Cornering Model' was used to confirm some basic suspension design rules established for optimising the lateral adhesion of a suspension design. The importance of controlling camber and vehicle jacking by an appropriate suspension design was identified. A detailed vehicle model was built-up using the simulation code AUTOSIM. After validating the model against proving ground data, some parametric studies were conducted to quantify the effects of suspension and tyre properties on the transient limit response behaviour. Proving ground and simulation results suggest that response time lags and cross- correlation coefficients in combination with other handling parameters can be used as objective quality measures. The results quantified to what extent tyre and chassis modifications change the limit handling behaviour.

The robust loop-shaping control methodology is applied in the flight control system design of the Cranfield A3 Observer unmanned, unstable, catapult launched air vehicle. Detailed linear models for the full operational flight envelope of the air vehicle are developed. The nominal and worst-case models are determined using the v-gap metric. The effect of neglecting subsystems such as actuators and/or computation delays on modelling uncertainty is determined using the v-gap metric and shown to be significant. Detailed designs for the longitudinal, lateral, and the combined full dynamics TDF controllers were carried out. The Hanus command signal conditioning technique is also implemented to overcome actuator saturation and windup. The robust control system is then successfully evaluated in the high fidelity 6DOF non-linear simulation to assess its capability of launch stabilization in extreme cross-wind conditions, control effectiveness in climb, and navigation precision through the prescribed 3D flight path in level cruise. Robust performance and stability of the single-point non-scheduled control law is also demonstrated throughout the full operational flight envelope the air vehicle is capable of and for all flight phases and beyond, to severe launch conditions, such as 33knots crosswind and exaggerated CG shifts. The robust TDF control law is finally compared with the classical PMC law where the actual number of variables to be manipulated manually in the design process are shown to be much less, due to the scheduling process elimination, although the size of the final controller was much higher. The robust control law performance superiority is demonstrated in the non-linear simulation for the full flight envelope and in extreme flight conditions.

This thesis presents the development of a computerized design synthesis for canard-delta combat aircraft. This is complementary to, and follows the philosophy of, an existing RAE system for conventional combat aircraft with swept wings (Ref. 1). The background to the work and the Research Programme objectives and limitations are initially examined. The design of a baseline canard-delta combat aircraft is then described together with all the assumptions and decisions which led to its final configuration. The philosophy behind the progressive evolution of the aircraft geometry and packaging modules from the baseline configuration is explained in detail. The development of detailed modules for the estimation of the aircraft aerodynamics and performance is then presented. A full description of the investigations into the effects of canard-delta interference on the aircraft aerodynamics is also included. The mathematical content of the aircraft geometry, packaging, aerodynamics and performance modules is presented separately in the appendices in greater detail. The development and architecture of the design synthesis and graphics programs are finally presented and the program operation is described with the aid of flow-charts. A comprehensive user's manual and a design example are also provided.