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Novel numerical optimisation of the Hohmann Spiral Transfer
No full textAs the revenue of commercial spacecraft platforms is generated by its payload, of which the capacity is maximised when fuel-mass is minimised, there is great interest in ensuring the fuel required for the trajectory to deliver the satellite to its working orbit is minimum. This paper presents an optimisation study of a novel orbit transfer, recently introduced by the authors through an analytical analysis, known as the Hohmann Spiral Transfer . The transfer is analogous to the bi-elliptic transfer but incorporating high and low-thrust propulsion. This paper has shown that substantial fuel mass savings are possible when utilizing the HST. For a transfer to Geostationary Earth Orbit it is shown that a fuel mass saving of approximately 320 kg (~ 5 - 10% of mwet ) is possible for a wet mass of 3000-6000 kg – whilst satisfying a time constraint of 90 days. Several trends in the gathered data are also identified that determine when the HST with high or low-thrust plane change should be used to offer the greatest fuel mass benefit
Hohmann spiral transfer with inclination change performed by low-thrust system
No full textThis paper investigates the Hohmann Spiral Transfer (HST), an orbit transfer method previously developed by the authors incorporating both high and low-thrust propulsion systems, using the low-thrust system to perform an inclination change as well as orbit transfer. The HST is similar to the bi-elliptic transfer as the high-thrust system is first used to propel the spacecraft beyond the target where it is used again to circularize at an intermediate orbit. The low-thrust system is then activated and, while maintaining this orbit altitude, used to change the orbit inclination to suit the mission specification. The low-thrust system is then used again to reduce the spacecraft altitude by spiraling in-toward the target orbit. An analytical analysis of the HST utilizing the low-thrust system for the inclination change is performed which allows a critical specific impulse ratio to be derived determining the point at which the HST consumes the same amount of fuel as the Hohmann transfer. A critical ratio is found for both a circular and elliptical initial orbit. These equations are validated by a numerical approach before being compared to the HST utilizing the high-thrust system to perform the inclination change. An additional critical ratio comparing the HST utilizing the low-thrust system for the inclination change with its high-thrust counterpart is derived and by using these three critical ratios together, it can be determined when each transfer offers the lowest fuel mass consumption. Initial analyses have shown the HST utilizing low-thrust inclination change to offer the greatest benefit at low R2 (R2 - R1) and large AI (AI > 30º). A novel numerical optimization process which could be used to optimize the trajectory is also introduced
Transferencia de Hohmann
Get PDFEn este artículo se define la Transferencia de Hohmann, una de las transferencias orbitales más utilizadas, por su economía y simplicidad.
En su descripción se deducen el valor de los impulsos necesarios para su ejecución y el propelente requerido.
En el estudio se considera que las maniobras aplicadas son todas impulsivas (tiempo breve de encendido).
Se describe y estudia la transferencia de Hohmann entre dos órbitas circulares y se hace un análisis de ellas dando una explicación de la paradoja
de Hohmann. Finalmente se muestran las posibilidades de realizar transferencias de Hohmann entre dos órbitas elípticas.
Tras cada razonamiento se presenta algún ejemplo para mostrar su aplicación a diferentes situaciones.Moraño Fernández, JA. (2021). Transferencia de Hohmann. https://riunet.upv.es/handle/10251/164021DE
Father Othmar Hohmann
No full textFather Othmar Hohmann helps on the construction of the St. James Catholic Church
Raw data and scripts for "The Period-Modulated Harmonic Locked Loop (PM-HLL): A low-effort algorithm for rapid time-domain multi-periodicity estimation"
No full textThis package contains all required scripts to generate the simulations and figures from the study "The Period-Modulated Harmonic Locked Loop (PM-HLL): A low-effort algorithm for rapid time-domain multi-periodicity estimation" by Volker Hohmann, published in Acta Acustica:
The Period-Modulated Harmonic Locked Loop (PM-HLL): A low-effort algorithm for rapid time-domain multi-periodicity estimation
Volker Hohmann
Acta Acust. 5 56 (2021)
DOI: 10.1051/aacus/2021050
When referring to this work, please cite the journal paper.
Note that additive noise is generated at random, i.e., small differences in the estimation accuracy occur when repeating a simulation. For further details see the journal paper.
Thank you for downloading the package. Your comments are very welcome!
Method patented: DE Patent DE102021207339B3
Author: Volker Hohmann, Carl von Ossietzky University of Oldenburg, GermanyFunded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – Project-ID 352015383 – SFB 1330 – project B2
Variaciones de la Transferencia de Hohmann: Segmentada y Bielíptica
Get PDFAunque la transferencia de Hohmann es la maniobra de dos impulsos más eficiente entre dos órbitas circulares si permitimos más de dos impulsos aparecen otras posibilidades.
En este artículo se presentan dos variantes de la transferencia de Hohmann: La Transferencia de Hohmann Segmentada y la Transferencia de Hohmann Bielíptica. Tras cada exposición se presentan ejemplos para mostrar su aplicación a diferentes situaciones. Además se hace una comparativa entre las transferencias de Hohmann estándard y bielíptica.Moraño Fernández, JA. (2021). Variaciones de la Transferencia de Hohmann: Segmentada y Bielíptica. https://riunet.upv.es/handle/10251/164017DE
Rendezvous con transferencias de Hohmann
Get PDFEste artículo presenta dos formas de hacer una primera aproximación al rendezvous entre dos objetos mediante transferencias de Hohmann. En realidad se muestran las condiciones de posicionamiento en las que se puede realizar, los tiempos necesarios para su transición y los impulsos requeridos para su ejecución.
En el caso de transferencias interplanetarias se estudian solo los
casos entre órbitas circulares y coplanarias.Moraño Fernández, JA. (2022). Rendezvous con transferencias de Hohmann. https://riunet.upv.es/handle/10251/183741DE
On properties of the Hohmann transfer
No full textIn this work, we present a complete study of the Hohmann transfer maneuver between two circular coplanar orbits. After revisiting its known properties, we present a number of supplementary properties which are essential to the qualitative understanding of the maneuver. Specifically, along a Hohmann transfer trajectory, there exists a point where the path inclination is maximum: this point occurs at midradius and is such that the spacecraft velocity equals the local circular velocity. This implies that, in a Hohmann transfer, the spacecraft velocity is equal to the local circular velocity three times: before departure, at midradius, and after arrival. In turn, this allows the subdivision of the Hohmann transfer trajectory into a region where the velocity is subcircular and a region where the velocity is supercircular, with the transition from one region to another occurring at midradius.
Also, we present a simple analytical proof of the optimality of the Hohmann transfer and complement it with a numerical study via the sequential gradient-restoration algorithm. Finally, as an application, we present a numerical study of the transfer of a spacecraft from the Earth orbit around the Sun to another planetary orbit around the Sun for both the case of an ascending transfer (orbits of Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto) and the case of a descending transfer (orbits of Mercury and Venus)
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