{"id":144,"date":"2015-07-22T16:08:20","date_gmt":"2015-07-22T16:08:20","guid":{"rendered":"http:\/\/airborne.geophysicsgpr.com\/?page_id=144"},"modified":"2017-03-09T15:25:11","modified_gmt":"2017-03-09T15:25:11","slug":"gravimetrie","status":"publish","type":"page","link":"https:\/\/airborne.geophysicsgpr.com\/fr\/techniques\/gravimetrie\/","title":{"rendered":"Gravim\u00e9trie"},"content":{"rendered":"<div id=\"pl-144\"  class=\"panel-layout\" ><div id=\"pg-144-0\"  class=\"panel-grid panel-no-style\" ><div id=\"pgc-144-0-0\"  class=\"panel-grid-cell\" ><div id=\"panel-144-0-0-0\" class=\"so-panel widget widget_sow-editor panel-first-child panel-last-child\" data-index=\"0\" ><div class=\"texte-home-right article panel-widget-style panel-widget-style-for-144-0-0-0\" ><div\n\t\t\t\n\t\t\tclass=\"so-widget-sow-editor so-widget-sow-editor-base\"\n\t\t\t\n\t\t>\n<div class=\"siteorigin-widget-tinymce textwidget\">\n\t<p>La gravim\u00e9trie a\u00e9roport\u00e9e est une technologie de pointe qui sollicite autant la mesure du champ gravitationnel terrestre que l\u2019extr\u00eame pr\u00e9cision du positionnement et de l\u2019attitude de l\u2019avion. Le d\u00e9fi est de soustraire \u00e0 la mesure de l\u2019acc\u00e9l\u00e9ration verticale due \u00e0 l\u2019attraction terrestre, l\u2019ensemble des acc\u00e9l\u00e9rations subies par l\u2019avion ou l\u2019h\u00e9licopt\u00e8re lors du vol.<\/p>\n<h2 class=\"h2resize\">Type de senseur utilis\u00e9 pour la gravim\u00e9trie<\/h2>\n<p>Le GT-1A est un senseur gravim\u00e9trique GPS-INS scalaire vertical install\u00e9 sur une plateforme inertielle \u00e0 trois axes, elle-m\u00eame install\u00e9e sur un support antivibratoire. Ce system peut aussi bien \u00eatre utilis\u00e9 dans un avion que dans un h\u00e9licopt\u00e8re.<\/p>\n<p>Le senseur principal p\u00e8se environ 50 kg. Ensemble, le senseur et la plateforme inertielle mesurent 40 x 40 x 70 cm. Le support antivibratoire poss\u00e8de une fr\u00e9quence de coupure d\u2019approximativement 5 Hz et a une dimension de 60 cm de diam\u00e8tre par 22 cm de hauteur, donnant au syst\u00e8me complet une taille de 92 cm.<\/p>\n<p>Les performances du syst\u00e8me se d\u00e9crivent comme suit :<\/p>\n<p>Sous les conditions suivantes, l\u2019erreur sur la mesure de l\u2019anomalie gravim\u00e9trique est \u00e9valu\u00e9e \u00e0 0.6 mGal RMS utilisant un filtre de 100 secs (fr\u00e9quence de coupure de 0.01 Hz) :<\/p>\n<ul>\n<li>Acc\u00e9l\u00e9ration verticale inf\u00e9rieure \u00e0 +\/- 500 mGal \u00e0 300 Hz;<\/li>\n<li>Installation optimale des antennes GPS sur l\u2019a\u00e9ronef et au sol;<\/li>\n<li>Utilisation de r\u00e9cepteurs GPS double fr\u00e9quences;<\/li>\n<li>Taux d\u2019\u00e9chantillonnage GPS \u00e0 2 Hz.<\/li>\n<\/ul>\n<p>\u00a0<\/p>\n<p>\u00a0<\/p>\n<p>Pour plus d'informations, veuillez contacter notre <a style=\"color: #3a5568\" href=\"mailto:info@geophysicsgpr.com\">\u00c9quipe de lev\u00e9 a\u00e9roport\u00e9<\/a>.<\/p>\n<\/div>\n<\/div><\/div><\/div><\/div><\/div><div id=\"pg-144-1\"  class=\"panel-grid panel-no-style\" ><div id=\"pgc-144-1-0\"  class=\"panel-grid-cell\" ><div id=\"panel-144-1-0-0\" class=\"so-panel widget widget_sow-image panel-first-child panel-last-child\" data-index=\"1\" ><div class=\"panel-widget-style panel-widget-style-for-144-1-0-0\" ><div\n\t\t\t\n\t\t\tclass=\"so-widget-sow-image so-widget-sow-image-default-8b5b6f678277-144\"\n\t\t\t\n\t\t>\n<div class=\"sow-image-container\">\n\t\t<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/airborne.geophysicsgpr.com\/wp-content\/uploads\/sites\/8\/2015\/07\/grav_heli.jpg\" width=\"412\" height=\"275\" srcset=\"https:\/\/airborne.geophysicsgpr.com\/wp-content\/uploads\/sites\/8\/2015\/07\/grav_heli.jpg 412w, https:\/\/airborne.geophysicsgpr.com\/wp-content\/uploads\/sites\/8\/2015\/07\/grav_heli-300x200.jpg 300w, https:\/\/airborne.geophysicsgpr.com\/wp-content\/uploads\/sites\/8\/2015\/07\/grav_heli-272x182.jpg 272w\" sizes=\"auto, (max-width: 412px) 100vw, 412px\" title=\"Gravim\u00e9trie\" alt=\"Gravim\u00e9trie\" \t\tclass=\"so-widget-image\"\/>\n\t<\/div>\n\n<\/div><\/div><\/div><\/div><div id=\"pgc-144-1-1\"  class=\"panel-grid-cell\" ><div id=\"panel-144-1-1-0\" class=\"so-panel widget widget_sow-image panel-first-child panel-last-child\" data-index=\"2\" ><div class=\"panel-widget-style panel-widget-style-for-144-1-1-0\" ><div\n\t\t\t\n\t\t\tclass=\"so-widget-sow-image so-widget-sow-image-default-8b5b6f678277-144\"\n\t\t\t\n\t\t>\n<div class=\"sow-image-container\">\n\t\t<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/airborne.geophysicsgpr.com\/wp-content\/uploads\/sites\/8\/2015\/07\/grav.jpg\" width=\"367\" height=\"531\" srcset=\"https:\/\/airborne.geophysicsgpr.com\/wp-content\/uploads\/sites\/8\/2015\/07\/grav.jpg 367w, https:\/\/airborne.geophysicsgpr.com\/wp-content\/uploads\/sites\/8\/2015\/07\/grav-207x300.jpg 207w\" sizes=\"auto, (max-width: 367px) 100vw, 367px\" title=\"Airoborne_Technique_Gravimetry\" alt=\"Gravim\u00e9trie\" \t\tclass=\"so-widget-image\"\/>\n\t<\/div>\n\n<\/div><\/div><\/div><\/div><\/div><\/div>","protected":false},"excerpt":{"rendered":"<p>La gravim\u00e9trie a\u00e9roport\u00e9e est une technologie de pointe qui sollicite autant la mesure du champ gravitationnel terrestre que l\u2019extr\u00eame pr\u00e9cision du positionnement et de l\u2019attitude de l\u2019avion. Le d\u00e9fi est de soustraire \u00e0 la mesure de l\u2019acc\u00e9l\u00e9ration verticale due \u00e0 l\u2019attraction terrestre, l\u2019ensemble des acc\u00e9l\u00e9rations subies par l\u2019avion ou l\u2019h\u00e9licopt\u00e8re lors du vol.Type de senseur&#8230;  <a href=\"https:\/\/airborne.geophysicsgpr.com\/fr\/techniques\/gravimetrie\/\" class=\"more-link\" title=\"Read Gravim\u00e9trie\">Read more &raquo;<\/a><\/p>\n","protected":false},"author":1,"featured_media":632,"parent":15,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"page-full-width.php","meta":{"content-type":"","footnotes":""},"class_list":["post-144","page","type-page","status-publish","has-post-thumbnail","hentry"],"_links":{"self":[{"href":"https:\/\/airborne.geophysicsgpr.com\/fr\/wp-json\/wp\/v2\/pages\/144","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/airborne.geophysicsgpr.com\/fr\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/airborne.geophysicsgpr.com\/fr\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/airborne.geophysicsgpr.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/airborne.geophysicsgpr.com\/fr\/wp-json\/wp\/v2\/comments?post=144"}],"version-history":[{"count":12,"href":"https:\/\/airborne.geophysicsgpr.com\/fr\/wp-json\/wp\/v2\/pages\/144\/revisions"}],"predecessor-version":[{"id":1011,"href":"https:\/\/airborne.geophysicsgpr.com\/fr\/wp-json\/wp\/v2\/pages\/144\/revisions\/1011"}],"up":[{"embeddable":true,"href":"https:\/\/airborne.geophysicsgpr.com\/fr\/wp-json\/wp\/v2\/pages\/15"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/airborne.geophysicsgpr.com\/fr\/wp-json\/wp\/v2\/media\/632"}],"wp:attachment":[{"href":"https:\/\/airborne.geophysicsgpr.com\/fr\/wp-json\/wp\/v2\/media?parent=144"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}