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There are 30 million people in remote, rural communities in China without access to electricity. The government of China has initiated an ongoing effort to provide constant, reliable power to these citizens. Renewable energy is being utilized to solve this problem, which necessitates the use of a storage medium for energy, because renewable energies (i.e. wind and/or solar power) are inherently intermittent, variable, and largely unpredictable. By storing excess energy when it is plentiful (for a maximum feasible time of two days) and distributing it to the community in times of scarcity, the intermittent power is effectively leveled and auxiliary power is provided. A high-inertia flywheel was designed for this application because of its simplicity, ease of maintenance, low cost, and reliability. This design addresses many problems including bearing losses, aerodynamic losses, and distribution losses. The proposed design consists of a six spoke layout with a large outer ring.

Significant environmental and economic benefit could be obtained if spark ignited (SI) engines could be made more efficient. Engine operation using leaner fuel air mixtures at higher power densities and pressures promise higher thermal efficiencies. Mixtures required for such operation are often difficult to ignite with traditional spark plugs. In pursuit of better ignition sources, this paper presents a high-level model of an alternative microwave plasma ignition source under development. In this publication, atmospheric measurements of a pulsed microwave ignitor are used to derive an empirical model that will allow for control and increased energy delivery to the device. The model accounts for a simplistic plasma formation delay, a drop in resonance frequency as a result of plasma formation, and a subsequent change in associated microwave reflection coefficient.

At flight levels above the ceiling of 10,000 feet, during the operational phase of a sensor deployment system for a C-130 aircraft, it becomes necessary to seal the cargo hold to maintain pressure for the safety and comfort of the crew and operators. In order for the sensor deployment System to have full mission support capabilities for DoD reconnaissance needs, a system must be designed where-by the cargo area may be sealed once the system has been deployed. Currently, with the sensor pod in position, the ramp can be closed to within a few inches of the locked position. The door in this position, for stability during flight, must be locked and structurally supported to maintain the aircrafts design requirements. This presents the first of a series of issues that must be examined for the success of the final design. To seal the remaining area, an expanding “bladder-seal” has been developed.

Current research has involved manipulating the ignition inside of the combustion chamber. It has been demonstrated that an RF plasma flame can be generated from microwaves in a Quarter Wave Coaxial Cavity Resonator (QWCCR). By using this method, it may become possible for researchers to improve combustion and ignition characteristics of a modern internal combustion engine. Filling a plasma cavity with an appropriate dielectric medium can both alter electromagnetic properties and provide a suitable protective barrier to the harsh condition inside of a combustion cylinder. It is the purpose of this paper is to investigate both the operating frequency and quality factor of dielectric-filled cavities, as well as to suggest dielectrics that would be suitable for such an application.

The Federal Test Procedure (FTP) for heavy-duty engines requires the use of a full-flow tunnel based constant volume sampler (CVS) which is costly to build and maintain, and requires a large workspace. A portable micro-dilution system that could be used for measuring on-board, in use emissions from heavy duty vehicles would be an inexpensive alternative compared to a full-flow CVS tunnel, as well as requiring significantly less workspace. This paper evaluates such a portable particulate matter measuring system. This micro-dilution tunnel operates on the same principle as a full-flow tunnel, however dilution ratios can be more easily controlled with the micro dilution system. The dilution ratios for the micro-dilution system were maintained at least four to one, as per ISO 8178 requirements, by measuring the mass flow rates of the dilution air and dilute exhaust.

When designing the Oculus sensor platform, many safety issues such as designing fail safes, adapting to flying situations, and examining situations produced by exposure to real-world conditions were taken into consideration. When predicting maintenance issues, environmental conditions that the platform will have to encounter were assessed. A material that was lightweight and strong enough to withstand the harsh environmental conditions experienced outside the C-130 aircraft was needed. In addition to the material used, another issue addressed was the ability to repair the platform easily and efficiently. Normal operations expose the components to significant wear and tear, which requires the replacement of parts to maintain safe operations. Oculus was constructed to allow for component replacement without deconstruction of the entire platform. While environmental factors were a concern, mechanical design and functionality, along with safety, was vital to the project.

Project Oculus is an in-flight deployable mechanical arm/pod system that will accommodate 500 pounds of sensor payload, developed for a C-130 military aircraft. The system is designed for use in counter narco-terrorism and surveillance applications by the Department of Defense and the National Guard [1]. A prototype of the system has been built and is in the testing/analysis phase. The purpose of this study was to analyze the actual stresses and strains in the critical areas found using previous Finite Element (FE) simulations and to ensure that acceptable safety requirements have been met. The system components tested will be redesigned, tested, and reconstructed in the case of unacceptable safety factors or if more reliable methods can be implemented. The system was built to be deployed and retracted in flight, to avoid causing any problems in take off and landing.

In this analysis the structural integrity of the rotational system of a standardized roll-on, roll-off sensor pallet system was authenticated. The driving force behind this analysis was to ensure the structural integrity of the system and to locate the areas with optimization potential. This process will ideally lead to the weight reduction of individual components thereby allowing for the transportation of greater cargo during flight. Scaling down of these excessive areas will also allow for a reduced production cost and an increase in efficiency of the system. The study was comprised of the failure susceptibility of the individual components of the system. The major results include the optimization potential of individual components, as well as strategically rating and categorizing the failure capability of the components.

Project Oculus, an experimental configurable sensor platform for deploying airborne sensors on a C-130 aircraft, is currently in its pre-flight testing phase. The electronics driving the platform are available commercially off the shelf (COTS) and as such are not automatically rated to comply with stringent military electromagnetic standards as defined in MIL-STD-461. These COTS electronics include efficient switching power converters, variable frequency motor drives (VFD), and microprocessor based equipment, all of which can present electromagnetic interference (EMI) issues. Even in a design where EMI issues were not considered up front, it is often possible to bring the overall configuration into compliance. Switching and digital clock signals produce both conducted and radiated noise emissions. Long cable runs and enclosure apertures become noise transmitting antennas. Large switching currents place noise on the power lines causing interference with other equipment.

The purpose of this study was to optimize the current design of the roll-on, roll-off sensor deployment system support arm for the C-130 Hercules. The Department of Defense (DOD) and the National Guard (NG) will be using these sensor pallet systems in a variety of command and control configurations for counter narco-terrorism applications along with several other applications. The original design for the sensor deployment arm will be drawn using CAD, and then a Finite Element Analysis will be modeled and analyzed using Pro/ENGINEER and Pro/MECHANICA. This will show the stress concentrations and the areas where weight can be saved. The most concerning variable will be the height of the mechanical arm attachment. By decreasing that height, and shortening the mechanical arm, the moments will decrease, and the required torque will be less.

The Quarter Wave Coaxial Cavity Resonator (QWCCR) plasma igniter is designed, from previous theoretical work, as an ignition source for an internal combustion engine. The present research has explored the implementation of the QWCCR into an internal combustion (IC) engine. The QWCCR design parameters of inner conductor length, loop geometry, and loop position were varied for two igniters of differing operating frequency. Variations of the QWCCR radio frequency (RF) parameters, as a function of engine geometry, were studied by placing the igniter in a combustion chamber and manually varying the crank position. Three identical igniters were fitted with dielectric inserts and the parameters were studied before and after ignition was sustained in a twin-cylinder engine. Optimal resonator geometries were determined. Radio frequency parameter invariance was found with respect to crank angle and piston distance. The first successful IC engine ignition using a QWCCR was achieved.

A quarter-wave radio frequency coaxial cavity plasma ignitor can be used to generate a combustion-initiating energy source in an internal combustion engine. This paper outlines research results on the development of such an ignitor. The system, which operates in the 820 - 900 MHz frequency range, uses a high Q quarter-wave cavity that generates plasma when resonating. Pressure testing has shown that the device can generate plasmas at spark ignition compression pressures. A resonator operating at these frequencies has been attached to a static combustion chamber and modeled numerically in order to determine the operational characteristics of the device in a combustion chamber.

A complete three-dimensional thermal finite element analysis has been performed for the Beta version of an axial vane rotary engine. This work investigated the effects of the heat flow for two different geometric designs (kinematic inversions): rotor turning with vane turning and cams turning with a non-rotating vane. The output from a modified zero dimensional combustion code was used to establish the thermal boundary conditions in the finite element model. An iterative procedure between the thermal finite element model and the zero dimensional code was used to obtain the component wall temperature profile. Updating the combustion model wall temperature resulted in different thermal characteristics than those from the constant wall temperature solution. The thermal analysis provided a quantitative comparison of the different geometric versions of the engine, showing where improvements must be made.

It has been proposed that an automated remote color inspection of automobile body panels is possible with a reasonably precise color measurement. This paper outlines a test of a new 3D color measurement technology as applied to this task and presents the results of the first test. A camera is set up several feet away from a car body; a 3D orientation measuring system takes both 3D and color data from the car. The raw data is presented as a set of 3D graphs; the geometry-corrected data is also provided. Statistical analysis is presented to indicate system precision.

A family of transmission systems based on a “Planetary Gear - CVT” mechanism is presented here. The systems considered consist of two compound planetary gear trains connected through a CVT pulley system to provide the power/torque split and recirculation function, without the use of additional clutches and/or chain drives. A two degree of freedom system results in which one of the degrees of freedom is directly related to the CVT ratio. The mechanisms considered here combine the gear reduction function of compound planetary gear trains with the continuously variable trans- used as a circulating power control unit. The kinematics and dynamics of this family of systems is presented with emphasis on the belt forces, torques on the various shafts and the overall input/output velocity ratios through the CVT ratio span. Then a parametric analysis is conducted to characterize the effect of the various functional ratios and parameters of the system in terms of the overall performance.

In this paper, a new method for the hydro-dynamic analysis of a sliding cylinder in a fully lubricated parallel track is presented. The method is an extension of Booker's “Mobility Method” (developed for cylindrical journal bearings) to the case of sliding cylinders, in which the clearance between the track and the cylinder, the viscosity of the lubricant, the radius and length of the pin, the sliding velocity and the applied transverse load determine the hydrodynamic behavior of the cylinder. In the Rand Cam™ Engine [1]*, the axicycloidal motion of vanes is driven by a rotor and a cylindrical cam, and one of the alternative designs to provide this function is based on a cylindrical pin sliding within a track which follows the profile of the motion of the main cams of the engine. This function is very important for the engine, since it separates the load bearing function from the sealing function left to the apex-like seals.

Analysis of two types of bearings has been performed for the rotor shaft of the Rand Cam™ engine. Rolling element bearings and a combination of journal and thrust bearings for selected engine configurations have been considered. The engine configurations consist of four, five, six, seven, and eight vanes. The bearing geometry and orientation was also addressed. This analysis is crucial due to the potentially large axial loading on the bearings and the need for the bearing arrangement to be compact and reliable. An emphasis was placed on the combination of fluctuating axial and radial loads and the resulting effect upon the bearings. Tapered roller bearings were found to be effective. However, a combination of journal and thrust bearings is a more compact bearing arrangement for this application. The eight vane configuration is the most desirable configuration based upon the bearing analysis.

The Rand-Cam engine is a positive displacement machine, operating on a four stroke cycle, which consists of a rotor with multiple axial vanes forming combustion chambers as the rotor and vanes rotate in a cam shaped housing. The cam housing, consisting of two “half-housings” or stators, contains a toroidal trough of varying depth machined into each stator. The two stators are phased so that the shallowest point on one trough corresponds to the deepest on the other. A set of six vanes, able to move axially through machined holes in the rotor, traverses the troughs creating six captured zones per side. These zones vary in volume with rotor rotation. Since each trough has two deep sections and two shallow sections with ramps in between, full four stroke operation is obtained between each pair of vanes in each trough, corresponding to twelve power “strokes” per revolution.

The Rand Cam engine is a novel design which avoids the use of pistons in favor of a cavity of varying size and shape. A set of vanes protrudes from a rotor into a circular trough in a stator. The vanes seal to the walls and base of the trough, which is of varying depth, and progress around the trough with rotation of the rotor. These vanes therefore pass through the rotor and are constrained to move parallel to the rotational axis. Intake and exhaust processes occur through ports in the stator wall which are revealed by the passing vanes. Advantages of the basic design include an absence of valves, reduction in reciprocating masses, presence of an integral flywheel in the rotor and strong fluid movement akin a swirl induced by the relative velocity between the rotor and stator.

In this paper an approach is presented for the system parameterization and synthesis of a Rand-Cam® Engine configuration based on an axial-cylindrical cam driven mechanism. This engine consists of a stationary axial-cylindrical cam on which axially moving pistons (vanes) sweep around the cam as they are driven by the rotor, providing the volume displacement as the rotor delivers the rotary output torque directly to the shaft. It has been documented that this engine configuration has some unique features that make it particularly suitable for high power to weight ratio applications. The modeling strategy makes use of higher order curve and surface modeling techniques and object modeling approaches based on profile extruding, blending operations and constructive solid geometry. Some of the resulting models are further used for finite element engineering analysis through a programmatic logic built into the parameterized general model.