Browse Topic: Fuels and Energy Sources
ABSTRACT The recent climate change plan for the United States Army states that hybridized combat vehicles will enter the fleet by 2050. The Bradley Fighting Vehicle (BFV) and its family of vehicles are prime candidates for hybridization. This paper sets out to perform a drive cycle analysis for the BFV using its traditional powertrain along with hybridized powertrains. The analysis considers both series and parallel hybrid architectures, where the size of the batteries are based on modifications to the existing powertrain. Three different drive cycles are considered – stationary, highway, and off-road. The model accounts for accelerative forces, transmission losses, cooling losses, drag, road grade, tractive losses, and ancillary equipment. The results indicate that both parallel and series hybrids provide reduced fuel consumption and increased range. Of the two, the series hybrid architecture provides more overall benefits. The study concludes by discussion of the technical challenges
In non-cooperative environments, unmanned aerial vehicles (UAVs) have to land without artificial markers, which is a key step towards achieving full autonomy. However, the existing vision-based schemes have the common problems of poor robustness and generalization, and the LiDAR-based schemes have the disadvantages of low resolution, high power consumption and high weight. In this paper, we propose an UAV landing system equipped with a binocular camera to preform 3D reconstruction and select the safe landing zone. The whole system only consists of a stereo camera, and the innovation of the solution is fusing the stereo matching algorithm and monocular depth estimation(MDE) model to get a robust prediction on the metric depth. The whole landing system consists of a stereo matching module, a monocular depth estimation (MDE) module, a depth fusion module, and a safe landing zone selection module. The stereo matching module uses Semi-Global Matching (SGM) algorithm to calculate the
ABSTRACT The US Army is seeking improvements in the fuel efficiency of their military vehicles.. They have initiated a number of R&D projects aimed at advancing the state-of-the-art of powertrain efficiency including demonstration in a laboratory environment. This effort will set a benchmark for the vehicle integrators, allowing them to improve future vehicle offerings. The SAIC, AVL, Badenoch, QinetiQ and Ker-Train Research team offered powertrain solutions from 7 Tons to 40 Tons that achieved the goal of 44% thermal efficiency and the stringent flexible fuel and emissions requirements. In each of these offerings the team was able to identify modifications to existing engines that allowed dramatic improvements in the thermal efficiency. These efficiency improvements were achieved through a combination of techniques, combustion cycle adjustments using in-cylinder pressure monitoring and precise control of fuel injector timing, and turbo-compounding. For the R&D project, the fuel
ABSTRACT Connected and automated vehicles (CAVs) leverage onboard sensing and external connectivity using Vehicle-to-Vehicle (V2V), Vehicle-to-Infrastructure (V2I) and Vehicle-to-Everything (V2X) technologies to "know" the upcoming operating environment with some degree of certainty, significantly narrowing prior information gaps. These technologies have been traditionally developed and used for driver assistance and safety but are now being used to operate the vehicle more efficiently [1–5]. The eco-driving algorithm, which leverages the data available through these streams, performs two key functions: (1) acceleration smoothing and (2) eco-approach and departure (Eco-AND) at signalized intersections. The algorithm uses information from neighboring vehicles and signalized intersections to calculate an energy-efficient speed trajectory. This paper presents the development of an Android-based driver advisory application that leverages cellular Internet connectivity and Traffic
Abstract Military vehicles need prime power and auxiliary power systems with ever-increasing power density and specific power, as well as greater fuel economy, lower noise, lower exhaust emissions and greater stealth. D-STAR technologies, funded by the Army, DARPA, Marine Corps / Navy and others, are enabling a new generation of modified-HCCI (homogenous charge compression ignition) engines that simultaneously offer power density and specific power of racing-quality gasoline engines, operation on JP-8 and other heavy fuels, as well as the other desirable qualities mentioned above. D-STAR Engineering has recently developed a prototype for a 1 kW man-portable heavy-fuel hybrid power system, that has been successfully tested by the ONR / USMC, and has demonstrated the power core for a 2 kW hybrid power system (for Army TARDEC). D-STAR is also developing, based on funding from the Army, a 500 Watt hybrid power system, and has designs for hybrid heavy fuel power systems and APUs for 10 and
ABSTRACT Situations exist that require the ability to preposition a basic level of energy infrastructure. Exploring and developing the arctic’s oil potential, providing power to areas damaged by natural or man-made disasters, and deploying forward operating bases are some examples. This project will develop and create a proof-of-concept electric power prepositioning system using small autonomous swarm robots each containing a power electronic building block. Given a high-level power delivery requirement, the robots will self-organize and physically link with each other to connect power sources to storage and end loads. Each robot mobile agent will need to determine both its positioning and energy conversion strategy that will deliver energy generated at one voltage and frequency to an end load requiring a different voltage and frequency. Although small-scale robots will be used to develop the negotiation strategies, scalability to existing, large-scale robotic vehicles will be
ABSTRACT The demand for electrical power in ground combat vehicles has been consistently increasing over the years. In the years to come, abundant onboard electrical power, along with a modernized power system to manage and distribute it, will enable leap ahead capabilities for the warfighter. A carefully architected electrical power system will also help to improve fuel efficiency while reducing maintenance and logistics burden
ABSTRACT This paper summarizes development and demonstration of F-24/JP-8-fueled Fuel-Cell Electric-Vehicle that offers silent-mobility, silent-watch, and export-power. The prototype electric vehicle was fueled with MIL-SPEC F-24/JP-8. It can potentially be operated with other logistic fuels and does not require onboard hydrogen storage. An onboard fuel reformer with integrated sulfur trap was used for processing MIL-SPEC F-24/JP-8. The 10-kW electric (kWe) generator included a solid oxide fuel cell and balance of plant components (oxidizer, pumps, blowers, sensors, power and control electronics). It was hybridized with a rechargeable battery for startup, peak loads, and load following. Water neutrality and silent operation (i.e., ~60 dBA at 1-meter) was confirmed. The power produced was sufficient for vehicle propulsion and export power. Both 28-32 VDC and 110 VAC for charging batteries and supporting external load demands were available onboard. Initial off-road demonstrations were
ABSTRACT The roll-up roll-away Tactical Vehicle-to-Grid / Vehicle-to-Vehicle (V2G/V2V) system provides a plug-and-play, very fast forming, smart, aggregated, and efficient power solution for an emerging (including austere) contingency base that is ready to generate up to 240kW of 208 VAC 3-phase power in less than 20 minutes. The system is designed to provide grid services (peak shaving, Volt/VAR control, power regulation, and current source mode) beneficial to emerging and mature grids (CONUS or OCONUS). The system uses vehicle Transmission-Integrated Generators (TIGs) to produce 600VDC power for use by vehicle hotel-loads (electrification) and off-board loads (tents/shelters, communications centers, or other electrical loads). Each vehicle is equipped with a Vehicle Communication Module (VCM), which provided the communication capability prior to initiation of transfer of up to 100kW of power via the J1772 SAE Combo Connector between vehicles (V2V) and/or for export power off-vehicle
ABSTRACT To realize the full potential of simulation-based evaluation and validation of autonomous ground vehicle systems, the next generation of modeling and simulation (M&S) solutions must provide real-time closed-loop environments that feature the latest physics-based modeling approaches and simulation solvers. Real-time capabilities enable seamless integration of human-in/on-the-loop training and hardware-in-the-loop evaluation and validation studies. Using an open modular architecture to close the loop between the physics-based solvers and autonomy stack components allows for full simulation of unmanned ground vehicles (UGVs) for comprehensive development, training, and testing of artificial intelligence vehicle-based agents and their human team members. This paper presents an introduction to a Proof of Concept for such a UGV M&S solution for severe terrain environments with a discussion of simulation results and future research directions. This conceptual approach features: 1
ABSTRACT The U.S. Department of Defense faces growing fuel demand, resulting in increasing costs and compromised operational capability. In response to this issue, the Fuel Efficient Ground Vehicle Demonstrator (FED) program was initiated in order to demonstrate a tactical vehicle with significantly greater fuel efficiency than a Humvee while maintaining capability. This article provides an overview of a systems engineering methodology for maximizing fuel efficiency and its application in concept development for the FED program. Engineering tools and methods used include tradespace definition, provisional baseline product models, decomposition of energy expenditure over the product usage cycle, structured technology market surveys, complex systems modeling & simulation tools, and design space exploration / Pareto optimization. The methodology explores the impact of technology on fuel efficiency along with other aspects of vehicle development including drive cycle definition
ABSTRACT Cylinder Pressure Monitoring (AVL CYPRESS™) is a technology which provides closed-loop feedback to enable real-time control of combustion in a compression ignition engine. This makes it possible to adapt to the fuel ignition quality and energy density by adjusting the main injection quantity and the placement of the injection events. The engine control system can thus detect fuel quality and adapt the combustion phasing quickly and robustly – and without any prior knowledge of fuel properties. By using a cylinder pressure sensor(s), the engine controller will be able to map the development of the apparent rate of heat release (ARHR) and the mass fuel burn curve - which provides good thermal efficiency correlation. The cylinder pressure map detects the combustion event and the feedback controller adjusts the start of injection to maintain the combustion event at the desired crank position. The cylinder pressure sensor allows for accurate measurement of the power produced. By
ABSTRACT This paper will discuss via case study both military and civilian hybrid vehicle development focusing on the processes required from the selection of the hybrid propulsion system architecture, component down-selection using advanced modeling and simulation tools, body/chassis development and integration, design verification testing using an advanced dynamometer test facility, and final full vehicle validation on the test track. The paper will incorporate results from the FED (Fuel Efficiency Demonstrator) program where AVL is responsible in collaboration with World Technical Services Inc., for delivering a fully developed hybrid propulsion system integrated into the demonstrator vehicle
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