Search results for "propulsion"
showing 4 items of 44 documents
A Hybrid Storage Systems for All Electric Aircraft
2021
A hybrid energy storage system specifically designed for a fully electric aircraft is presented in the paper. The analysis of the time evolution of the power demand of the electric propulsion system during a test mission of Maxwell X-57, an all-electric aircraft developed by NASA, has pointed out the presence of significant peak power during take-off and air tack. Considered the issues related to weight and the volume of the energy storage systems (ESSs) in all-electric aircraft, a hybridization of aircraft ESS with a Supercapacitors (SCs) bank, devoted to smooth peak power demand, has been investigated. A comparison between the simulation results of an electrochemical battery and hybrid ES…
Energy minimization of single input orbit transfer by averaging and continuation
2006
AbstractThis article deals with the transfer between Keplerian coplanar orbits using low propulsion. We focus on the energy minimization problem and compute the averaged system, proving integrability and relating the corresponding trajectories to a three-dimensional Riemannian problem that is analyzed in details. The geodesics provide approximations of the extremals of the energy minimization problem and can be used in order to evaluate the optimal trajectories of the time optimal and the minimization of the consumption problems with continuation methods. In particular, minimizing trajectories for transfer towards the geostationary orbit can be approximated in suitable coordinates by straig…
The Aquatic Surface Robot (AnSweR), a Lightweight, Low Cost, Multipurpose Unmanned Research Vessel
2021
Even though a few examples of aquatic surface robots exist, they are generally expensive, relatively large and heavy and tailored to custom-made hardware/software components that are not openly available to a broad public. In this work, the Aquatic Surface Robot (AnSweR), a newly-designed, lightweight, low cost, open-source, multipurpose unmanned research vessel is presented. The AnSweR features a lightweight and compact design that makes it fit in a backpack. Low-noise operation (in and above the surface) is achieved with a propulsion system based on two water-jets. Only affordable commercial-off-the-shelf (COTS) components are adopted. The primary goal of the AnSweR is to map underwater l…
A innovative laterals hydro floating tilting systems for USV or surface nautical vehicles
2015
The proposed project shows the results obtained in the implementation and testing in lacustrine and marine environment of an innovative laterals hydro floating tilting systems control for USV or remote/autonomous surface nautical vehicles. This vehicle is based on a pending patent belonging to Palermo University (Patent Pending RM2012A000209 and RM2012A000209). The system allows, during operation as a vehicle USV, set changes sailing trim and make turns with very narrow angle with little shunting movements. In fact the main benefits obtained were able to change or adjust the navigation structure by changing the tilt of one or two hydro floating during navigation without intervening directly…