{"id":8660,"date":"2021-05-13T16:03:17","date_gmt":"2021-05-13T15:03:17","guid":{"rendered":"https:\/\/bis-space.com\/shop\/?post_type=product&#038;p=8660"},"modified":"2021-05-13T16:03:17","modified_gmt":"2021-05-13T15:03:17","slug":"optimization-and-guidance-of-very-low-thrust-transfers-to-geostationary-orbit","status":"publish","type":"product","link":"https:\/\/bis-space.com\/shop\/product\/optimization-and-guidance-of-very-low-thrust-transfers-to-geostationary-orbit\/","title":{"rendered":"Optimization and Guidance of Very Low-Thrust Transfers to Geostationary Orbit"},"content":{"rendered":"","protected":false},"excerpt":{"rendered":"<h3>J. Gil-Fernandez; L. Tarabini; M. Graziano; M. A. Gomez-Tierno (2008),\u00a0<i>JBIS<\/i>,\u00a0<b>61<\/b>, 139-145<\/h3>\n<p><b>Refcode<\/b>: 2008.61.139<br \/>\n<b>Keywords<\/b>: Trajectory optimization, low-thrust, optimal control, non-linear programming, guidance<\/p>\n<p><b>Abstract:<\/b><br \/>\nA new hybrid direct-indirect optimization algorithm is presented to compute the minimum-time transfer between two orbits, including the phasing with a desired spacecraft. Very-low thrust means several hundred revolutions to perform the large change in orbital elements. The optimal control solution of the fast-evolution problem combined with a direct method for the secular trajectory avoids the numerical instability arising in very long propagations, decreases the computational time, reduces the sensitivity to the initial guess and provides a feasible transfer at every optimization step. Optimization of transfers from GTO to GEO is presented and two types of trajectories are analysed, sub-synchronous (apogee constrained below GEO altitude) and super-synchronous (free apogee altitude). The optimization of a transfer from LEO to a very high orbit (11 x 23 R<sub>E<\/sub>) is presented, showing the applicability of the method to different problems. A guidance algorithm is presented to compensate the deviations of the real trajectory from the optimal one due to off-nominal conditions. The results in closed-loop simulation of the guidance scheme to compensate deterministic perturbations not considered in the optimization show good performances in both analysed missions.<\/p>\n","protected":false},"featured_media":8662,"template":"","meta":{"_members_access_role":[],"_members_access_error":""},"pwb-brand":[],"product_brand":[],"product_cat":[56,59,158],"product_tag":[1861,1369,1862,1863,1864],"class_list":["post-8660","product","type-product","status-publish","has-post-thumbnail","product_cat-journal-of-the-bis","product_cat-papers","product_cat-2008papers","product_tag-guidance","product_tag-low-thrust","product_tag-non-linear-programming","product_tag-optimal-control","product_tag-trajectory-optimization","first","instock","downloadable","virtual","purchasable","product-type-simple","czr-hentry"],"jetpack_sharing_enabled":true,"brands":[],"_links":{"self":[{"href":"https:\/\/bis-space.com\/shop\/wp-json\/wp\/v2\/product\/8660","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/bis-space.com\/shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/bis-space.com\/shop\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/bis-space.com\/shop\/wp-json\/wp\/v2\/media\/8662"}],"wp:attachment":[{"href":"https:\/\/bis-space.com\/shop\/wp-json\/wp\/v2\/media?parent=8660"}],"wp:term":[{"taxonomy":"pwb-brand","embeddable":true,"href":"https:\/\/bis-space.com\/shop\/wp-json\/wp\/v2\/pwb-brand?post=8660"},{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/bis-space.com\/shop\/wp-json\/wp\/v2\/product_brand?post=8660"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/bis-space.com\/shop\/wp-json\/wp\/v2\/product_cat?post=8660"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/bis-space.com\/shop\/wp-json\/wp\/v2\/product_tag?post=8660"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}