The continuously increasing demand for clean renewable energy has rekindled interest in multi-terminal high voltage direct current (HVDC) grids. Although such grids have several advantages and a great potential, their materialization has been thwarted due to the absence of HVDC breakers. In comparison with traditional alternating current (AC) breakers, they should operate and interrupt fault currents in a time frame of a few milliseconds. The aim of this thesis is focused on the design of ultra-fast electro-mechanical actuator systems suitable for such HVDC breakers.Initially, holistic multi-physics and hybrid models with different levels of complexity and computation time were developed to simulate the entire switch. These models were validated by laboratory experiments. Following a generalized analysis, in depth investigations involving simulations complemented with experiments were carried out on two of the sub-components of the switch: the ultra-fast actuator and the damper. The actuator efficiency, final speed, peak current, and maximum force were explored for different design data.The results show that models with different levels of complexity should be used to model the entire switch based on the magnitude of the impulsive forces. Deformations in the form of bending or elongation may deteriorate the efficiency of the actuator losing as much as 35%. If that cannot be avoided, then the developed first order hybrid model should be used since it can simulate the behavior of the mechanical switch with a very good accuracy. Otherwise, a model comprising of an electric circuit coupled to an electromagnetic FEM model with a simple mechanics model, is sufficient.It has been shown that using a housing made of magnetic material such as Permedyn, can boost the efficiency of an actuator by as much as 80%. In light of further optimizing the ultra-fast actuator, a robust optimization algorithm was developed and parallelized. In total, 20520 FEM models were computed successfully for a total simulation time of 7 weeks. One output from this optimization was that a capacitance of 2 mF, a charging voltage of 1100 V and 40 turns yields the highest efficiency (15%) if the desired velocity is between 10 m/s and 12 m/s.The performed studies on the passive magnetic damper showed that the Halbach arrangement gives a damping force that is two and a half times larger than oppositely oriented axially magnetized magnets. Furthermore, the 2D optimization model showed that a copper thickness of 1.5 mm and an iron tube that is 2 mm thick is the optimum damper configuration. / <p>QC 20150422</p>

Vibratory gyroscopes have gained immense popularity in the microsystem technology because of their suitability to planar fabrication techniques. With considerable effort in design and fabrication, MEMS (Micro-electro-mechanical-system) vibratory gyroscopes have started pervading consumer electronics apart from their well known applications in aerospace and defence systems. Vibratory gyroscopes operate on the Coriolis principle for sensing rates of rotation of the r tating body. They typically employ capacitive or piezoresistive sensing for detecting the Coriolis force induced motion which is, in turn, used to determine the impressed rate of rotation. Interestingly, Nature also uses vibratory gyroscopes in its designs. Over several years, it has evolved an incredibly elegant design for vibratory gyroscopes in the form of dipteran halteres. Dipterans are known to receive mechanosensory feedback on their aerial rotations from halteres for their flight navigation. Insect biologists have also studied this sensor and continue to be fascinated by the intricate mechanism employed to sense the rate of rotation. In most Diptera, including the soldier fly, Hermetia illucens, the halteres are simple cantilever like structures with an end mass that probably evolved from the hind wings of the ancestral four-winged insect form. The halteres along with their connecting joint with the fly’s body constitute a mechanism that is used for muscle-actuated oscillations of the halteres along the actuation direction. These oscillations occur in the actuation plane such that any rotation of the insect body, induces Coriolis force on the halteres causing their plane of vibration to shift laterally by a small degree. This induced deflection along the sensing plane (out of the haltere’s actuation plane) results in strain variation at the base of the haltere shaft, which is sensed by the campaniform sensilla. The goal of the current study is to understand the strain sensing mechanism of the haltere, the nature of boundary attachments of the haltere with the fly’s body, the reasons of asymmetrical geometry of the haltere, and the interaction between both wings and the contralateral wing and haltere. In order to understand the haltere’s strain sensing mechanism, we estimate the strain pattern at the haltere base induced due to rotations about the body’s pitch, roll, and yaw axes. We model the haltere as a cantilever structure (cylindrical stalk with a spherical end knob) with experimentally determined material properties from nanoindentation and carry out analytical and numerical (finite element) analysis to estimate strains in the haltere due to Coriolis forces and inertia forces resulting from various body rotations. From the strain pattern, we establish a correlation between the location of maximum strain and the position of the campaniform sensilla and propose strain sensing mechanisms. The haltere is connected to the meta thoracic region of the fly’s body by a complicated hinge mechanism that actuates the haltere into angular oscillations with a large amplitude of 170 ◦ in the actuation plane and very small oscillation in the sensing plane. We aim to understand the reason behind the dissimilar boundary attachments along the two directions. We carry out bending experiments using micro Newton force sensor and estimate the stiffness along the actuation and sensing directions. We observe that the haltere behaves as a rigid body in the actuation direction and a flexible body in the sensing direction. We find the haltere to be a resonating structure with two different kinds of boundary attachments in the actuation and sensing directions. We create a finite element model of the haltere joint based on the optical and scanning microscope images, approximate material properties, and stiffness properties obtained from the bending experiments. We subsequently validate the model with experimental results. The haltere geometry has asymmetry along the length and the cross-section. This specific design of the haltere is in contrast to the the existing MEMS vibratory gyroscope, where the elastic beams supporting the proof mass are typically designed with symmetric cross-sections so that there is a mode matching between the actuation and the sensing vibrations. The mode matching provides high sensitivity and low bandwidth. Hence, we are interested in understanding the mechanical significance of the haltere’s asymmetry. First, we estimate the location of the maximum stress by using the actual geometry of the haltere. Next, by using the stiffness determined from bending experiments and mass properties from the geometric model, we find the natural frequencies along both actuation and sensing directions. We compare these findings with existing MEMS vibratory gyroscopes. The dipteran halteres always vibrate at the wing beat frequency. Each wing maintains 180 ◦ phase difference with its contralateral haltere and the opposite wing. Both wings and the contralateral wing-haltere mechanism exhibit coupled oscillatory motion through passive linkages. These linkages modulate the frequency and maintain the out- of-phase relationship. We explore the dynamics behind the out-of-phase behaviour and the frequency modulation of the wing-wing and wing-haltere coupled oscillatory motion. We observe that the linear coupled oscillatory model can explain the out-of-phase relationship between the two wings. However, a nonlinear coupled oscillator model is required to explain both frequency synchronization and frequency modulation of the wing with the haltere. We also carry out a finite element analysis of the wing-haltere mechanism and show that the out-of-phase motion between the wing and the haltere is due to the passive mechanical linkage of finite strength and high actuation force. The results of this study reveal the mechanics of the haltere as a rate sensing gyroscope and show the basis of the Nature’s design of this elegant sensor. This study brings out two specific features— the large amplitude actuated oscillations and the asymmetric geometry of the haltere structure— that are not found in current vibratory gyroscope designs. We hope that our findings inspire new designs of MEMS gyroscopes that have elegance and simplicity of the haltere along with the desired performance.

Microdispositivos piezelétricos tem uma vasta aplicação em mecânica de precisão, como, por exemplo, manipulação de células, microcirurgias, equipamentos de nanotecnologia e principalmente em microeletromecanismos (MEMS). Os microdispositivos piezelétricos considerados nesta tese essencialmente consistem de uma estrutura multi-flexível atuada por duas ou mais piezocerâmicas, que geram deslocamentos e forças em direções e regiões pré-determinadas do domínio, ou seja, a estrutura multi-flexível atua como um transformador mecânico amplificando e alterando os deslocamentos gerados pelas piezocerâmicas nos movimentos de atuação. O desenvolvimento destes microdispositivos piezelétricos em sua grande maioria não utiliza ferramentas sistemáticas e genéricas. A complexidade dos movimentos de atuação torna o desenvolvimento dos microdispositivos piezelétricos complexo, principalmente devido ao surgimento de movimentos indesejados ou acoplados durante a sua atuação. Portanto, é necessário um método sistemático e eficiente como o método de otimização topológica (MOT), que incorpore na sua formulação as principais exigências de projeto dos microdispositivos, como apresentado nesse trabalho. O MOT implementado é baseado na abordagem CAMD (Distribuição Contínua da Distribuição de Material), onde as pseudo-densidades são interpoladas nos nós de cada elemento finito, resultando numa distribuição contínua de material no domínio. Um método adjunto foi implementado para o cálculo das sensibilidades. São consideradas três formulações. A primeira denominada de MAPs (Multi-Atuadores Piezelétricos) considera as regiões piezocerâmicas fixas, otimizando apenas a estrutura multi-flexível no domínio de projeto. Nesta formulação materiais não-piezelétricos (como, por exemplo, Alumínio) e vazio são distribuídos no domínio de projeto, mantendo as regiões piezocerâmicas fixas e homogêneas. Para validar os resultados obtidos com essa formulação foram fabricados protótipos de nanoposicionadores $XY$, que foram caracterizados experimentalmente utilizando técnicas de interferometria laser, considerando excitação quasi-estática. No entanto, essa primeira formulação impõe restrições no problema, limitando a optimalidade da solução obtida pela otimização topológica. Assim, surgiu a necessidade de desenvolver uma segunda formulação, que permite distribuir simultaneamente material não-piezelétrico, piezelétrico e vazio no domínio de projeto, denominada de LOMPs (Localização Ótima do Material Piezelétrico). A formulação dos LOMPs obtém simultaneamente a localização do material piezelétrico na estrutura flexível otimizada pela OT, e inclui também uma variável de projeto para determinar o ângulo ótimo entre as direções de polarização e do campo elétrico. Nesta formulação como as posições dos eletrodos não são conhecidas, ``a priori\'\', é utilizado como abordagem aplicar um campo elétrico constante para determinar a localização do material piezelétrico e conseqüentemente dos eletrodos. Finalmente, foi explorado o conceito de materiais com gradação funcional (MGFs) no projeto dos MAPs. Os MGFs apresentam uma distribuição contínua de materiais na sua microestrutura, não possuindo interface entre os materiais distribuídos, o que possibilita aumentar a vida útil do dispositivo piezelétrico. Assim, foi implementado uma terceira formulação denominada de MAPs MGFs, que permite obter a gradação ótima de materiais piezelétricos e não-piezelétricos no domínio piezocerâmico dos MAPs, conjuntamente com a topologia da estrutura multi-flexível. Essa formulação foi estendida para projetar atuadores bilaminares MGFs. Todas as formulações desenvolvidas utilizam uma função multi-objetivo, que permite controlar a rigidez e a flexibilidade minimizando o movimento acoplado, de cada movimento de atuação. Os exemplos numéricos são limitados a modelos bi-dimensionais, utilizando o estado plano de tensões e deformações mecânicas e elétricas, uma vez que a grande maioria das aplicações dos microdispositivos piezelétricos são bi-dimensionais. / Microtools offer significant promise in a wide range of applications such as cell manipulation, microsurgery, nanotechnology processes, and many other fields. The microtools considered in this doctoral thesis essentially consist of a multi-flexible structure actuated by two or more piezoceramic devices that when each piezoceramic is actuated, it generates an output displacement and force at a specified point of the domain and direction. The multi-flexible structure acts as a mechanical transformer by amplifying and changing the direction of the piezoceramic output displacements. Thus, the development of microtools requires the design of actuated flexible structures that can perform complex movements. The development of these microtools is still in the beginning and it can be strongly enhanced by using design tools. In addition, when multiple piezoceramic devices are involved, coupling effects in their movements become critical, especially the appearance of undesired movements, which makes the design task very complex. One way to avoid such undesirable effects is the use of a systematic design method, such as topology optimization, with appropriate formulation of the optimization problem. The topology optimization method implemented is based on the CAMD (Continuous Approximation of Material Distribution) approach where fictitious densities are interpolated at each finite element, providing a continuum material distribution in the domain. The corresponding sensitivity analysis is presented using the adjoint method. Three formulations are considered. The first formulation, called Piezoelectric Multi-Actuators (PMAs), keeps fixed piezoceramic positions in the design domain and only the flexible structure is designed by distributing some non-piezoelectric material (Aluminum, for example). $XY$ Piezoelectric Nanopositioner are manufactured and experimentally analyzed to validate the results of the topology optimization obtained using this formulation. Experimental analyses are conducted using laser interferometry to measure displacement, while considering a quasi-static excitation. However, this first formulation imposes a constraint to the position of piezoelectric material in the optimization problem limiting the optimality of the solution. Thus, the second formulation presented, called LOMPs, allows the simultaneous distribution of non-piezoelectric and piezoelectric material in the design domain, to achieve certain specified actuation movements. The optimization problem is posed as the simultaneous search for an optimal topology of a flexible structure as well as the optimal position of piezoceramics in the design domain and optimal rotation angle of piezoceramic material axes that maximize output displacements or output forces at a specified point of the domain and direction. When the distribution of a non-piezoelectric conductor material and a piezoceramic material is considered in the design domain, the electrode positions are not known ``a priori\'\'. To circumvent this problem, an electric field is applied as electrical excitation. Finally, the concept of functionally graded materials (FGM) is applied to PMAs design. FGMs are special materials that possess continuously graded properties without interfaces which can increase lifetime of piezoelectric devices. Thus, a third formulation is implemented to find the optimum gradation and polarization sign variation of piezoceramic FGMs, while simultaneously optimizing the multi-flexible structural configuration. This formulation is extended to design bimorph type FGM actuators. For all developed formulations, a multi-objective function is defined that controls the stiffness and flexibility, minimizing the coupling movement of each actuated movement. The present examples are limited to two-dimensional models because most part of the applications for such micro-tools are planar devices.

No description available.

This thesis presents a new mechanical design for an exoskeleton actuator to power the sagittal plane motion in the human hip. The device uses a DC motor to drive a Scotch yoke mechanism and series elasticity to take advantage of the cyclic nature of human gait and to reduce the maximum power and control requirements of the exoskeleton. The Scotch yoke actuator creates a position-dependent transmission that varies between 4:1 and infinity, with the peak transmission ratio aligned to the peak torque periods of the human gait cycle. Simulation results show that both the peak and average motor torque can be reduced using this mechanism, potentially allowing a less powerful motor to be used. Furthermore, the motor never needs to reverse direction even when the hip joint does. Preliminary testing shows the exoskeleton can provide an assistive torque and is capable of accurate position tracking at speeds covering the range of human walking. This thesis provides a detailed analysis of how the dynamic nature of human walking can be leveraged, how the hip actuator was designed, and shows how the exoskeleton performed during preliminary human trials.

The main goal of this work is to introduce with the basic technologies of manufacturing MEMS (Micro-electro-mechanical-systems). Further there is mentioned properties and manufacturing of CNT (Carbon nanotubes), used in manufacturing of capacitance pressure sensor.

The main goal of this work is to introduce new carbon structures - carbon nanotubes. The main objective of this work is to take advantage of the unique characteristic of carbon nanotubes to emit electrons at very low supply voltage.

A la croisée des chemins entre médecine et physique des ultrasons, ce travail de thèse s’est intéressé à l’apport de solutions diagnostiques et de thérapeutiques novatrices dans le domaine de l’électrophysiologie cardiaque. Un système capable de délivrer des ultrasons focalisés dans le cœur par voie transoesophagienne sous guidage par ultrasons a été développé et testé in vivo chez 6 porcs. Les tirs HIFU ont été délivrés sur les oreillettes et les ventricules. Lors de l'autopsie, une analyse visuelle a démontré la présence de lésions thermiques dans les zones ciblées chez 3 animaux. Ces lésions ont été confirmées par analyse histologique (taille moyenne: 5,5 mm2 x 11 mm2). Aucune lésion thermique œsophagienne n'a été observée. Un animal a présenté une bradycardie due à un bloc auriculo-ventriculaire, ce qui a permis de confirmer une réelle interaction entre les tirs HIFU et le tissu nodal cardiaque. Nous avons cependant observé un manque de précision, principalement lié aux mouvements cardiaques ainsi qu’aux structures anatomiques situées entre les zones ciblées et le transducteur de thérapie. Ces difficultés ont été principalement reliées à l’anatomie du modèle porcin, loin de celle de l’être humain. La recherche d'un meilleur modèle a conduit à des tests d'imagerie concluants sur des babouins.Des expériences supplémentaires ont été conduites afin d'améliorer la cartographie des arythmies ventriculaires et le suivi de la formation de lésions pendant l'ablation.Des expériences ont été menées sur les ventricules gauches de quatre coeurs de porcs en mode travaillant. Le protocole visait à démontrer que différents modèles d'activation mécanique pouvaient être observés, que le ventricule soit en rythme sinusal, stimulé depuis l'épicarde ou l'endocarde. Des acquisitions d’imagerie de déformation électromécanique (EWI) ont été enregistrées sur les faces antérieures, latérales et postérieures du ventricule gauche. Les boucles ont été ensuite analysées à l’aveugle par deux lecteurs indépendants.Les interprétations des séquences EWI étaient correctes dans 89% des cas. Le taux de concordance globale entre les deux lecteurs était de 83%. Dans un ventricule stimulé, l'origine du front d'onde était focale et provenait de l'endocarde ou de l'épicarde stimulé. En rythme sinusal, le front d'onde était activé depuis tout l'endocarde, en direction de l'épicarde, à une vitesse de 1,7 ± 0,28 m.s-1. Les vitesses du front d'onde ont été mesurées respectivement lorsque l'endocarde ou l'épicarde étaient stimulés à une vitesse de 1,1 ± 0,35 m.s -1 et 1,3 ± 0,34 m.s-1 (p = NS). Nous avons aussi démontré sur des échantillons ex-vivo que l'imagerie trans oesophagienne par analyse des ondes de cisaillement (élastographie) pouvait cartographier l'étendue des lésions HIFU. Des tirs HIFU ont été réalisés à l'aide de la sonde trans oesophagienne sur des échantillons de blancs de poulet (n = 3), puis sur un modèle porcin ex vivo d'oreillette (gauche, n = 2) et de ventricule gauche (n = 1). L’élastographie a fourni des cartes de rigidité des tissus avant et après l'ablation. Les zones des lésions ont été obtenues par analyse et quantification des changements de couleur des tissus puis ont été comparées aux images par élastographie. Dans le blanc de poulet, la rigidité est passée en moyenne de 4.8±1.1 kPa à 20.5±10.0 kPa (ratio 5.0±3.2). Dans le ventricule gauche, la rigidité est passée en moyenne de 21.2±3.3kPa à 73.8±13.9kPa (ratio 3.7±1.2). Dans l’oreillette gauche, la rigidité est passée en moyenne de 12.2±4.3 kPa à 30.3±10.3 (ratio 3.2±2.0). En histologie, la taille des lésions variait de 0.1 à 1.5 cm2 dans la zone du plan d'imagerie. Les caractéristiques morphométriques étaient similaires entre histologie et élastographie / At the crossroads of medicine and physics, this work aimed to provide innovative diagnostic and therapeutic tools based on ultrasound, in the field of cardiac electrophysiology. A system capable of delivering HIFU into the heart by a transesophageal route using ultrasound (US) imaging guidance was developed and tested in vivo in six male pigs. HIFU exposures were performed on atria and ventricles. At the time of autopsy, visual inspection identified thermal lesions in the targeted areas in three of the animals. These lesions were confirmed by histologic analysis (mean size: 5.5 mm2 x 11mm2). No esophageal thermal injury was observed. One animal presented with bradycardia due to an atrio-ventricular block, which provides real-time confirmation of an interaction between HIFU and the electrical circuits of the heart. There was still a lack of accuracy, mainly related to cardiac motion, and to anatomical structures in between the targets and the transducer. It was mainly related to the in vivo model and its anatomy, far from the human’s. The search for a better model led to conclusive imaging tests on baboons. Additional experiments were conduced in order to improve the mapping of ventricular arrhythmias and the monitoring of lesion formation during ablation. First, experiments were conducted on left ventricles of four isolated working mode swine hearts. The protocol aimed at demonstrating that different patterns of mechanical activation could be observed whether the ventricle was in sinus rhythm, paced from the epicardium, or from the endocardium. Electromechanical wave imaging (EWI) acquisitions were recorded on the anterior, lateral, and posterior segments of the left ventricle. Loop records were blindly assigned to two readers. EWI sequences interpretations were correct in 89% of cases. The overall agreement rate between the two readers was 83%. When in a paced ventricle, the origin of the wave front was focal and originating from the endocardium or the epicardium. In sinus rhythm, wave front was global and activated within the entire endocardium towards the epicardium at a speed of 1.7±0.28 m.s-1. Wave front speeds were respectively measured when the endocardium or the epicardium were paced at a speed of 1.1 ± 0.35 m.s-1 vs 1.3±0.34 m.s-1 (p=NS). Lastly, we investigated the feasibility of a dual therapy and imaging approach with the same transoesophageal device. We demonstrated on ex-vivo samples that transoesophageal shear wave imaging (SWE) can map the extent of the HIFU lesions. HIFU ablation was performed with the transoesophageal probe on ex-vivo chicken breast samples (n=3), then atrium (left, n=2) and ventricle (left n=1, right n=1) of swine heart tissues. SWE provided stiffness maps of the tissues before and after ablation. Areas of the lesions were obtained by tissue color change with gross pathology and compared to SWE. Shear modulus of the ablated zones increased from 4.8±1.1 kPa to 20.5+/-10.0 kPa (ratio 5.0±3.2) in the chicken breast, from 12.2±4.3 kPa to 30.3±10.3 (ratio 3.2±2.0) in the atria and from 21.2±3.3kPa to 73.8±13.9kPa (ratio 3.7±1.2) in the ventricles. On gross pathology, the size of the lesions ranged from 0.1 to 1.5cm2 in the imaging plane area and morphometric characteristics were fitting with elasticity-estimated depths and widths of the lesions

Les récupérateurs d'énergie vibratoire électrostatiques (REV) sont des systèmes convertissant une partie de l'énergie cinétique de leur environnement en énergie électrique, afin d'alimenter de petits systèmes électroniques. Les REV inertiels sont constituées d'un sous-système mécanique bâti autour d'une masse mobile, ainsi que d'une interface électrique. Ces deux blocs sont couplés par un transducteur électrostatique. Cette thèse étudie l'amélioration des performances des REV par la conception optimisée de leur interface électrique. La première partie de cette thèse étudie une famille d'interfaces électriques appelées pompes de charge (PC). On commence par la construction d'une théorie formelle des PC. Des interfaces rapportées dans la littérature sont identifiées comme membres de cette famille. Cette dernière est ensuite complétée par une nouvelle topologie de PC. Une comparaison des différents PC est alors faite dans le domaine électrique, puis un outil semi-analytique est présenté pour la comparaison des PC en prenant en compte le couplage électromécanique. L'étude des PC se termine par la présentation d'une nouvelle méthode de mesure du potentiel d'électret des REV. La deuxième partie de la thèse présente une approche de conception radicalement différente de ce qui est présenté dans les travaux actuels sur les REV. Elle préconise une synthèse active de la dynamique de la masse des REV à travers leur interface électrique. Nous montrons d'abord que cela permet la conversion d'énergie en quantités proches des limites physiques, et ce à partir de vibrations d'entrée de forme arbitraire. Enfin, une architecture pour un tel REV est proposée et testée en simulation. / Electrostatic vibration energy harvesters (e-VEHs) are systems that convert part of their surroundings' kinetic energy into electrical energy, in order to supply small-scale electronic systems. Inertial E-VEHs are comprised of a mechanical subsystem that revolves around a mobile mass, and of an electrical interface. The mechanical and electrical parts are coupled by an electrostatic transducer. This thesis is focused on improving the performances of e-VEHs by the design of their electrical interface. The first part of this thesis consists in the study of a family of electrical interfaces called charge-pumps conditioning circuits (CPCC). It starts by building a formal theory of CPCCs. State-of-the-art reported conditioning circuits are shown to belong to this family. This family is then completed by a new CPCC topology. An electrical domain comparison of different CPCCs is then reported. Next, a semi-analytical tool allowing for the comparison of CPCC-based e-VEHs accounting for electromechanical effects is reported. The first part of the thesis ends by presenting a novel method for the measurement of e-VEHs' built-in electret potential. The second part of the thesis presents a radically different design approach than what is followed in most of state-of-the-art works on e-VEHs. It advocates for e-VEHs that actively synthesize the dynamics of their mobile mass through their electrical interface. We first show that this enables to convert energy in amounts approaching the physical limits, and from arbitrary types of input vibrations. Then, a complete architecture such an e-VEH is proposed and tested in simulations submitted to human body vibrations.

This paper describes the changes made from Cal Poly’s initial railgun system, the Mk. 1 railgun, to the Mk. 1.1 system, as well as the design, fabrication, and testing of a newer and larger Mk. 2 railgun system. The Mk. 1.1 system is developed as a more efficient alteration of the original Mk. 1 system, but is found to be defective due to hardware deficiencies and failure, as well as unforeseen efficiency losses. A Mk. 2 system is developed and built around donated hardware from the Naval Postgraduate School. The Mk. 2 system strove to implement an efficient, augmented, electromagnetic railgun and projectile system capable of firing an approximate 1g aluminum projectile to speeds exceeding 2 km/s. A novel three part projectile is proposed to mitigate rail and projectile degradation. Projectile and sabot system kinematic equations are derived and the projectile is designed and tested along with Mk. 2 barrel. A numerical electromechanical model is developed to predict the performance of the Mk. 2 system and projectile assembly, and predicts a final velocity for the fabricated system exceeding 3.5 km/s and an efficiency as high as 24%. Testing of the Mk. 2 system showed catastrophic failure of the projectile during initial acceleration, resulting in very short acceleration times and distance, low velocity projectiles, and low efficiencies. During further testing of various projectile configurations, the barrel structure failed due to a large internal arc. Future work for the Mk. 2 system is discussed, a revised external barrel structure suggested, and a solid, more conventional solid chevron projectile design suggested.