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The Scotch yoke in its various forms and inversions has received considerable attention as possible alternatives to the slider-crank for internal combustion engine use. As a recent entry, the Stiller-Smith Mechanism has shown promise as being a viable and strong option. In this study emphasis was placed on comparing the number and similarity of mechanism components and the balancing aspects of these components, implications of component and linkage motions, the severity of loading experienced by similar bearing surfaces within the engines, and some of the friction losses associated with these new motions. It was found that the Stiller-Smith Engine has significantly fewer moving parts. It was also found that journal bearings in the slider-crank engine were more severely loaded than those in the Stiller-Smith Engine. The linear reciprocating bearings in the Stiller-Smith Engine were more heavily loaded than the slider-crank piston skirts.

Continuously variable transmissions (CVTs) are usually used in small vehicles due to power limitations on the variable elements. Continuously variable power-split transmissions (CVPST) were developed in order to reduce the fraction of power passing through the variable elements [1,2]. The configuration presented in this paper includes a planetary gear train (PGT), which in combination with the CVT allows the power to be split and therefore increase the power envelope of the system. The PGT also provides a branch that can be used in a hybrid electric vehicle (HEV) operation through an electric motor. A conceptual design of a CVPST for a HEV is presented in this paper. The objectives are to show the different operational modes, with diagrams, perform a power analysis, develop the velocity and force equations and finally show the performance of the system with an example application.

Continuously variable transmissions, commonly known as CVT's, have been shown to be feasible alternatives to the conventional multi-step gear transmissions (standard or automatic) typically used in automotive applications. Most CVT applications, however, rely on a shaft-to-shaft transmission arrangement, in which the belt-sheave action limits the load capacity of the transmission, particularly at the high power ranges (low speed, high torque). In this paper, a system based on a combined planetary gear train and a continuously variable pulley system is presented. The uniqueness of this arrangement is that the variable pulleys provide a power/torque split and recirculation function, which, when combined with the planetary gear train function, produces a continuously variable power split transmission system.

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.

This paper describes the strategy for engineering design, modeling, and analysis of a planetary - CVT (Continuously Variable Transmission) system. The uniqueness of this mechanism arrangement resides in the combination of features associated to two conventional systems, namely a planetary gear train and a CVT pulley system, acting as a power circulation control unit. The pulley system features a manually activated control over the variable pitch ratios of the CVT, by means of which the overall system input/output velocity and power ratios can be controlled according the operational requirements. By using the belt drive as a feedback control unit (as opposed to the main driveline), one of the major problems or limitations of conventional CVT arrangements is overcome, namely the belt capacity of the system. Specifically, the output torque obtained through the planetary output shaft is greater than the torque circulating through the pulleys.

Corona discharge from a RF quarter wave coaxial cavity resonator is considered as a plasma ignition source for spark ignited (SI) internal combustion (IC) engines. The gaseous discharge processes associated with this device are analyzed using principles of gas kinetics and gaseous electronics, with assumed values for the electric field strength. Corona discharge occurs when the electric field shaped and concentrated by a single electrode exceeds the breakdown potential of the surrounding gas. Ambient electrons, naturally present due to ionizing radiation, drift in the direction of the externally applied field, gaining energy while undergoing elastic collisions with neutral molecules. After gaining sufficient energy they dissociate, excite, or ionize the neutral particles through inelastic collision, creating additional electrons. This process leads to avalanche electrical breakdown of the gas within about 10-8 sec.

The Oculus sensor deployment platform research and development was conducted by the Center for Industrial Research Applications (CIRA) at West Virginia University (WVU). Oculus is a cost-effective reconnaissance platform available for use on a C-130 aircraft variants B through H. This system has a base of two standard MIL-463L pallets, an operators station and sensor pallet, that are loaded and rolled into place. The fore pallet or operator’s station holds three controllers, processing equipment for sensor data, and power regulation equipment. The aft pallet, or sensor pallet, located on the cargo ramp, contains sensors that, when in position, can be pointed at the ground. These reconnaissance sensors are situated in a pod that is mounted to four arms to allow more than 200 degrees of rotation, and are mounted to a movable plate that allow for linear movement.

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.

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.

The commercially available RNG k-e turbulence model with enhanced wall treatment found in Fluent 6.1 was used to solve the flow over a V-22 Osprey wing equipped with blowing slots. The solutions were then compared to experimental data. Good correlation between the computational and experimental data was found. Download on the wing from the rotors while the aircraft is operating in vertical take-off and landing mode was found to be reduced by the blowing slots.

Previous studies have shown that using blowing slots can reduce the effects of the rotor downwash on the main wing of a tilt-rotor aircraft, particularly the V-22 Osprey. The current study investigates the placement and air velocity of the leading edge blowing slot for optimization of the download reduction. The realizable turbulent kinetic energy - rate of dissipation (rke) numerical model available in Fluent 6.2.12 was used to model the flow involved under the rotors and the subsequent downwash around the main wing. It was found that the leading edge blowing slot is most beneficial when it is placed just upwind of the separation point without blowing slots. In the current investigation the optimal configuration is found between 0 percent and 1 percent of the chord length.

Crashworthiness is a measure of a vehicle's structural integrity during mechanical impact and of its ability to absorb energy and provide occupant protection in crash situations. Finite element modeling has been successfully used to simulate collision events; the present work uses these techniques to simulate the side impact of a mid-size car in order to investigate the crash characteristics of a 45 km/hr impact. Five different analyses were conducted on orthogonal and oblique impacts under varying conditions. The numerical results from the first analysis were compared with published experimental crash results, showing favorable comparisons for this numerical model prediction.

In order to prepare for flight on-board a military aircraft with an experimental prototype system, a crash scenario analysis was performed to ensure safety of the aircraft and its crew. The following describes the crash analysis of the Oculus sensor pallet system in preparation for a flight test on a C-130 aircraft. In this particular case, the two units were analyzed individually in accordance with the loading standards outlined in MIL-HDBK-1791. The unit that deploys outside of the rear cargo ramp of the aircraft (sensor platform) was analyzed more closely than the system that remains locked (operator station) into the rail system of the aircraft. As the results show, both systems are capable of being subjected to crash loading forces.

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.

The Federal Test Procedure (FTP) for heavy-duty engines requires the use of a full-flow tunnel based constant volume sampler (CVS). These are costly to build and maintain, and require a large workspace. A small portable micro-dilution system that could be used on-board, for measuring emissions of in-use, heavy-duty vehicles would be an inexpensive alternative. This paper presents the rationale behind the design of such a portable particulate matter measuring system. The presented micro-dilution tunnel operates on the same principle as a full-flow tunnel, however given the reduced size dilution ratios can be more easily controlled with the micro dilution system. The design targets dilution ratios of at least four to one, in accordance with the ISO 8178 requirements. The unique features of the micro-dilution system are the use of only a single pump and a porous sintered stainless steel tube for mixing dilution air and raw exhaust sample.

The development of a standardized roll-on, roll-off (RoRo) sensor pallet system for a C-130 aircraft was conceived by the National Guard and the Counter Narco-Terrorism Technology Development Office to assist in counterdrug reconnaissance activities within the United States and surveillance and reconnaissance missions worldwide. West Virginia University was contracted to perform the design and development of this system because of their innovative design ideas. Before development, the design parameters were established by these two DoD agencies, their mission requirements and by the limitations of the C-130 aircraft. These limitations include using Commercial off the Shelf (COTS) and Government off the Shelf (GOTS) items when developing the system that must be universal on all C-130 aircrafts variants B thru H. Further design criteria are by the limitations of the C-130 aircraft and its existing mission requirements.

Enhancing the capabilities of established airframes to meet expanded mission requirements is preferential to the design of specialized aircraft. The high cost associated with the research and development of a specialized aircraft platform has shifted the concentration towards the modification of existing aircraft to support multiple C4ISR missions. The recently developed Oculus sensor deployment system is one such example of this trend, providing a fully integrated aerial visual enhancement platform with multi-mission capabilities. This paper provides a short survey of the Oculus sensor pallet system and overviews some of the multiple guidelines used which ensure that various remote sensing technologies may be securely and simultaneously deployed.

The downwash of the prop-rotor blades of the Bell/Boeing V-22 “Osprey” in hover mode creates an undesirable negative lift on the wing of the aircraft. This downforce can be reduced through a number of methods. Neglecting all other effects, such as power requirements, this research investigated the feasibility of using circulation control, through blowing slots on the leading and trailing edge of the airfoil to reduce the wake profile under the wing. A model was built at West Virginia University (WVU) and tested in a Closed Loop Wind Tunnel. The airfoil was placed normal to the airflow using the tunnel air to simulate the vertical component of the downwash experienced in hover mode. The standard hover mode flap angle of 67 degrees was used throughout the testing covered in this paper. All of these tests were conducted at a free stream velocity of 59 fps, and the baseline downforce on the model was measured to be 5.45 lbs.

During structural engineering design two of the most overlooked design facets of a finished product is understanding the behavior characteristics of how the product will react when resonated at its natural frequencies and actually defining and understanding the overall vibration profile responsible for the excitation of the structure. A C-130 mechanical arm/pod system has been developed to accommodate 1,000-pounds of sensor payload deployable in flight from a C-130 Hercules military aircraft (variants B thru J). The mechanical arm/pod system will be subjected to a profile of vibration from numerous sources during deployment and while in the final operating position. A general vibration profile for the mechanical arm/pod will be compiled from the plane’s four T-56-A-15 turboprop engines, the atmospheric turbulence and random gust loads.

The development of a mathematical model of StillerSmith Mechanism for the application of a 4-cylinder plunger pump system is presented. The magnitude and direction of the internal dynamic load are obtained by solving a set of equations using the overall geometric parameters, prescribed motions, inertia distribution, and applied torques on the system. The simulation presented here yields the history of the internal loads, which are then normalized with respect to the required peak output load on the plungers, through an entire rotary cycle. The approach allows for the development of further design criteria through parametric sensitivity studies.