Revolutionary Vertical Lift Technology (RVLT) Side-By-Side Hybrid Concept Vehicle Powertrain Dynamic Model

The Side-by-Side (SBS) Hybrid is one of several Revolutionary Vertical Lift Technology (RVLT) concept aircraft identified by NASA to investigate Urban Air Mobility (UAM) requirements. This paper presents a dynamic model of the SBS Hybrid powertrain built using the Toolbox for the Modeling and Analysis of Thermodynamic Systems (T-MATS) and the Electrical Modeling and Thermal Analysis Toolbox (EMTAT). The model consists of the rotors, electrical power system, and turboshaft engines connected through freewheeling clutches, gearboxes, and multiple shafts. This research effort models the complex behavior of the powertrain, including the operation of the freewheeling clutches and electrical power system at the simulation time scale of the shaft dynamics. Several simulations highlight the key features present in the model and demonstrate its operation.

Development and Evaluation of Personal Urban Concept Vehicle Powered by a Hydrogen Fuel Cell

To reduce the levels of harmful emissions and to minimize the noise pollution, many leading countries have started pilot projects and initiatives for gradual transition to electrical vehicles or vehicles powered by alternative fuel sources, including natural gas, hydrogen, propane, biofuels, and methanol. Parallel to this, many automotive companies are also exploring and using every possibility to introduce newer manufacturing technologies and materials in the vehicle development and construction processes. The results of these efforts are vehicles that are lighter and have lower fuel consumption, but at the same time are capable to provide the industry approved levels of comfort, reliability, and protection to the passengers. One of the many drivers for the abovementioned evolution of the automotive industry are the numerous events and races, where teams from different countries and continents are competing for dominance. The focus of this paper is to present the processes for design, development and evaluation of a hydrogen fuel cell powered racing vehicle, which was developed at the “Angel Kanchev” University of Ruse in Bulgaria. The paper presents results from simulated and real on-track experiments with the vehicle prototype. Emulations and analysis on the possibilities to improve the vehicle performance, as well as to increase the effectiveness of the vehicle power supply system, using a system for regenerative braking, are also provided in the last section of the paper.

Comparison of two community noise models applied to a NASA urban air mobility concept vehicle

Predictions of community noise exposure from the NASA urban air mobility (UAM) concept vehicles have been conducted for representative operations using the FAA Aviation Environmental Design Tool (AEDT) in order to demonstrate modeling tool interoperability and assess applicability, capabilities and limitations of integrated noise modeling tools. To both quantify limitations and highlight other capabilities, a comparative analysis is performed using a time simulation method, in particular, using the Volpe Advanced Acoustic Model (AAM). Starting with the same source noise model, the 3D directivity of a UAM concept vehicle is predicted in terms of aeroacoustic pressure time histories at a sphere of observers near the vehicle. In addition to distilling those data to a set of noise-power-distance data for input to AEDT, the data are processed preserving directivity, into narrowband, one-twelfth and one-third octave bands for input to AAM. Results from AEDT and AAM modeling are provided for a variety of metrics to demonstrate the effect that source noise and propagation modeling fidelity have on predicted results at receptors over a study area.

Revolutionary Vertical Lift Technology (RVLT) Side-by-Side Hybrid Concept Vehicle Powertrain Dynamic Model

The Side-by-Side (SBS) Hybrid is one of several Revolutionary Vertical Lift Technology (RVLT) concept aircraft identified by NASA to investigate Urban Air Mobility (UAM) requirements. This paper presents a dynamic model of the SBS Hybrid powertrain built using the Toolbox for the Modeling and Analysis of Thermodynamic Systems (T-MATS) and the Electrical Modeling and Thermal Analysis Toolbox (EMTAT). The model consists of the rotors, electrical power system, and turboshaft engines connected through freewheeling clutches, gearboxes, and multiple shafts. This research effort models the complex behavior of the powertrain, including the operation of the freewheeling clutches and electrical power system at the simulation time scale of the shaft dynamics. Several simulations highlight the key features present in the model and demonstrate its operation.

Balloon Locomotion for Extreme Terrain

BALLET (BALloon Locomotion for Extreme Terrain) is a new concept vehicle for robotic surface mobility on planetary bodies with atmospheres. The vehicle is composed of a buoyant balloon with 6 evenly-distributed suspended payload modules each serving as a foot for locomotion over inaccessible rugged terrain. While the physics of BALLET will apply on Venus and Mars, the environmental conditions and available component technology limit our consideration to Titan. We describe the concept in detail, its applications for science missions on Titan, mission deployment scenarios, analyses of the concept under varying environmental conditions and simulations of its locomotion. The concept is shown to be feasible and provides a new approach for exploration of rugged lakes, dunes, shorelines and cryovolcanic regions on Titan.

Innovative Chassis Made From EPP and CFRP of an Urban-Concept Vehicle

The paper presents a fully new chassis of a high efficiency vehicle for the Shell Eco-marathon competition. The chassis is realized by a sandwich structure with an expanded polypropylene (EPP) core and carbon fiber reinforced plastic (CFRP) external skins. The chassis is connected to the body to realize a safe and stiff structure. Numerical analyses have been performed to assess the stiffness, safety and dynamic eigenfrequencies of the chassis. A Finite Element model of the entire chassis and body was developed. The manufacturing process of the entire chassis and body is described in the paper and some data obtained during on-track tests of the vehicle are presented. The vehicle reached the 4th place at the 2019 edition of the Shell Eco-marathon competition, with an equivalent energy consumption of 184 km/kWh.