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In this paper, a mild hybrid drive train has been proposed. A small electric motor with low rated voltage (42 V) is used to (1) propel the vehicle at low speed, (2) replace the fluid-coupled torque converter and (3) realize regenerative braking. With proper design and control, the fuel economy in urban driving can be significantly improved without much change from conventional drive train to the mild hybrid drive train.

Significant amount of energy is lost in frequent braking, automatic transmission and engine idling for a conventional engine powered passenger car while driving in cities. In this paper, a mild hybrid vehicle drive train has been introduced. It uses a small electric motor with floating stator, called TRANSMOTOR and small and a battery pack. The transmotor functions as a generator, engine starter, frictionless clutch (electric torque coupler), regenerative braking and propelling. The mild hybrid drive train can effectively reduce the urban-driving fuel consumption by regenerative braking, eliminate of energy losses in conventional automatic transmission and engine idling. The drive train can use low voltage system (42V for example), due to the low electric power rating, and is more similar to conventional drive train than full hybrid vehicle. Therefore, less effort is needed to evolve it from conventional vehicles.

The rotary-vee engine is a novel and unusual internal combustion engine. The rotary-vee engine is unique in that all of the components have rotary motion, but the combustion chamber and piston design is similar to a reciprocating engine. Of particular significance, the rotary-vee engine design includes pistons with rings to accomplish the sealing of the combustion chamber. Thus, the rotary-vee engine may offer the sealing benefits of the conventional piston engine, and the vibration and balance characteristics of a rotary engine. This paper includes a review of rotary engines, and places the rotary-vee engine in the context of all rotary engines. In addition, a thermodynamic analysis of the operation of a rotary-vee engine is reported. The rotary-vee engine possesses some advantages relative to other rotary engine designs such as piston ring sealing, and the thermodynamic analysis indicates similar performance as compared to conventional reciprocating engines.

There is a growing interest in electric and hybrid electric vehicles (EV and HEV) due to their high efficiency and low emission. In EV and HEV, the characteristic of the traction motor is essential for the performance and efficiency of the EV and HEV. In this paper, the advantages of the extended constant power range characteristic of the traction motor for both propulsion and regenerative braking are analyzed. Simulation results are presented to verify the conclusions. Due to its several inherent advantages, especially its capability of having an extended constant power range, Switched Reluctance Motor (SRM) is proposed as the candidate of the traction motor in EV and HEV. The design methodology of SRM for achieving an extended constant power range and the control strategy of SRM for regenerative braking in EV and HEV are presented.

The desirable braking system of a land vehicle is that it can stop the vehicle or reduce the vehicle speed as quickly as possible, maintain the vehicle direction stable and recover kinetic energy of the vehicle as much as possible. In this paper, an electronically controlled braking system for EV and HEV has been proposed, which integrates regenerative braking, automatic control of the braking forces of front and rear wheels and wheels antilock function together. When failure occurs in the electric system, the braking system can function as a conventional man-actuated braking system. Control strategies for controlling the braking forces on front and rear wheels, regenerative braking and mechanical braking forces have been developed. The braking energy that can be potentially recovered in typical driving cycle has been calculated. The antilock performance of the braking system has been simulated.

A scoping thermal analysis was done to evaluate the general feasibility of capillary pumped heat engines. The analysis was motivated by recent advances in nanoscale materials science that have made it increasingly practical to manufacture high porosity wicks with a median pore diameter on the order of a few nanometers. Capillary pumped heat engines are shown to be generally feasible for wick evaporation rates equivalent to about 1 watt per square centimeter when wick material thermal conductivity on the order of a few W/m-K is assumed. A compact heat engine architecture, referred to as an integrated capillary engine, is introduced.

The possibility of recovering vehicle kinetic energy is one inherent advantage of electric and hybrid electric vehicles. When a vehicle drives in heavy traffic, for example in New York City, more than half of the total energy is dissipated in the brakes. Therefore, recovering braking energy is an effective approach for improving the driving range of EV and the energy efficiency of HEV. In this paper, three different braking patterns are investigated for evaluating the availability of braking energy recovery. The results indicate that even without active braking control, a significant amount of braking energy can be recovered, and the brake system does not need much changing from the brake systems of conventional passenger cars.

Electric power generation and conditioning have experienced revolutionary development over the past two decades. Furthermore, new materials such as high energy magnets and high temperature superconductors are either available or on the horizon. Our work is based on the promise that new technologies are an important driver of new power system concepts and architectures. This observation is born out by the historical evolution of power systems both in terrestrial and aerospace applications. This paper will introduce new approaches to designing space power systems by using several new technologies.

Computer algorithms were developed for generating the guidance parameters necessary to steer an agricultural tractor. A variety of field operations were considered in order that the guidance program be suited for general applications including travel in curved rows and following a single edge. Testing of the guidance algorithm was performed in the laboratory using simulated and videotaped images of rowcrops and tilled soil. From the images, yaw angle change of the tractor, direction value and offset error were computed. Prediction of the direction value and offset error compared well to measured values. Accuracy of the direction value was within +/- 0.5 degrees while the offset error was within +/- 0.05 meters. Good performance was observed for straight and curved rows as well as following a single edge.

The opportunity for the application of Wireless Power Transmission (WPT) technologies is growing. Applications covering terrestrial, airborne and space missions are evolving. Concepts for terrestrial systems for powering remotely located regions by the use of renewable energy sources; airborne systems used for remote observation, communication relay, and environmental monitoring; and space based systems for potentially powering the elements of a space infrastructure are being developed. This paper will present the history of wireless power transmission systems and summarize current and future applications and technology. Design constraints for terrestrial systems, airborne platforms and space systems will be presented.