{"id":1477,"date":"2011-07-20T04:14:11","date_gmt":"2011-07-20T08:14:11","guid":{"rendered":"http:\/\/www.etotheipiplusone.net\/?p=1477"},"modified":"2011-07-20T14:02:52","modified_gmt":"2011-07-20T18:02:52","slug":"a-slightly-less-sculpture-like-quadrotor","status":"publish","type":"post","link":"https:\/\/www.etotheipiplusone.net\/?p=1477","title":{"rendered":"A Slightly Less Sculpture-Like Quadrotor"},"content":{"rendered":"<p>Greetings, Internets. What&#8217;s the deal this time, I can&#8217;t even finish something before it goes live?! Anyways, to answer pretty much all questions about why the thing may or may not work, here&#8217;s a nice little video.<\/p>\n<p><iframe loading=\"lazy\" src=\"http:\/\/www.youtube.com\/embed\/_wrCEvWXME8\" frameborder=\"0\" width=\"425\" height=\"349\"><\/iframe><\/p>\n<p>That&#8217;s right, <em>it wiggles<\/em>. Having no left-handed fans (ball is in your court, <a href=\"http:\/\/www.hobbyking.com\/hobbyking\/store\/uh_viewItem.asp?idProduct=17617\" target=\"_blank\">Hobbyking<\/a>!), I could either use movable vanes or fixed angularly mounted fans to cancel the resultant torque from everything spinning in one direction. And by Robot Jesus if I&#8217;m going to have to mount something cockeyed or make something motorized and adjustable, I&#8217;m gonna do both of it at once. Hence, 1 dimensional thrust vectoring. Would that be like, thrust scalaring or something? The controlled wiggling should also let the vehicle translate and rotate without requiring thrust differential &#8211; it&#8217;s pointing the exhaust opposite the direction it wants to move the most in. This is the riskiest part of the whole project, and I am itching to see if it even makes sense.<\/p>\n<p>As the video shows, the electrical system is now fully wired up and ready. I spent the evening coding up a storm, getting some basic running code completed that lets me test the\u00a0 servos and determine their correct directions, and also calibrate the Turnigy S100A-HV controllers in software (as opposed to me twiddling a stick).<\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.etotheipiplusone.net\/pics\/edf\/edf52.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/www.etotheipiplusone.net\/pics\/edf\/edf52-mid.jpg\" alt=\"\" width=\"512\" height=\"384\" \/><\/a><\/p>\n<p>This is the primary wiring for one side. I ended up ditching the switch-in-the-middle idea after determining that the channels of the <a href=\"http:\/\/www.hobbyking.com\/hobbyking\/store\/uh_viewitem.asp?idproduct=10327&amp;aff=15144\" target=\"_blank\">HK Quattro<\/a> battery charger which charged the &#8220;high side&#8221; battery pack would also be mistakenly supplying power to the controllers. To eliminate this problem, I&#8217;d either have to add a second switch (pointless) or isolate all the battery charger channels from each other.<\/p>\n<p>Turning the Quattro from a single 4-channel charger into four isolated one-channel chargers takes a little bit of trace-cutting and the result needs 4 independent isolated power supplies, like laptop or monitor brick adapters. It&#8217;s been done before on the <a href=\"http:\/\/mitrocketscience.blogspot.com\/2010\/11\/mid-november.html\" target=\"_blank\">Jedboard project<\/a>, with a different model, but the Quattro isn&#8217;t that different. I&#8217;ll throw up some details on it later after my aforementioned laptop power bricks arrive.<\/p>\n<p>Once I decided to go with the four channel isolated charger route, I wired up the power normally &#8211; the master switch governs the positive battery rail only. There are two switches on my <a href=\"https:\/\/www.etotheipiplusone.net\/pics\/edf\/edf40.jpg\" target=\"_blank\">switch panel<\/a>, and the little one is a &#8220;precharge bypass&#8221; for the larger. Flipping this switch on before the larger key switch powers on the logic and also connects the controllers to the battery through a 10 ohm power resistor, letting the capacitance fill up slowly (instead of stepping from zero to 40 volts instantly, which would theoretically result in infinity amps). I decided there was enough bus capacitance involved in this whole system to warrant a precharge circuit.<\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.etotheipiplusone.net\/pics\/edf\/edf53.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/www.etotheipiplusone.net\/pics\/edf\/edf53-mid.jpg\" alt=\"\" width=\"512\" height=\"384\" \/><\/a><\/p>\n<p>I whipped up a quick charger panel with Deans connectors. The &#8220;isolation required&#8221; notice is just to make sure I never try shoving all the leads into eachother. There are no cell balance connectors here, though the packs have them; I&#8217;m going to balance the cells on a need basis only.<\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.etotheipiplusone.net\/pics\/edf\/edf54.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/www.etotheipiplusone.net\/pics\/edf\/edf54-mid.jpg\" alt=\"\" width=\"512\" height=\"384\" \/><\/a><\/p>\n<p>There was really no &#8220;signal wiring&#8221; to speak of for this build &#8211; the signals just plugged into eachother. In the center of the show is a <a href=\"https:\/\/sites.google.com\/site\/2007arduino\/\" target=\"_blank\">2.007 Arduino Nano incubato<\/a>r board, which was <em>custom-made, custom-paid, and cuuuuustom-fitted<\/em> for the 2.007 class.<\/p>\n<p style=\"text-align: center;\"><a href=\"https:\/\/www.etotheipiplusone.net\/pics\/edf\/edf55.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/www.etotheipiplusone.net\/pics\/edf\/edf55-mid.jpg\" alt=\"\" width=\"512\" height=\"384\" \/><\/a><\/p>\n<p>Each circuit has a 5v BEC module that feeds into the carrier board. This gives me a degree of redundancy in the logic power and also relieves the stress of feeding four (or more?) unhappy servos from one BEC. The BECs are the entry-level <a href=\"http:\/\/www.hobbyking.com\/hobbyking\/store\/uh_viewitem.asp?idproduct=10313&amp;aff=15144\" target=\"_blank\">Hobbyking HV 3 amp unit<\/a>.<\/p>\n<p>There&#8217;s nothing left but the software. Or is there?<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Greetings, Internets. What&#8217;s the deal this time, I can&#8217;t even finish something before it goes live?! Anyways, to answer pretty much all questions about why the thing may or may not work, here&#8217;s a nice little video. That&#8217;s right, it wiggles. Having no left-handed fans (ball is in your court, Hobbyking!), I could either use [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[81,5],"tags":[],"class_list":["post-1477","post","type-post","status-publish","format-standard","hentry","category-edf-quadrotor","category-project-build-reports"],"_links":{"self":[{"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=\/wp\/v2\/posts\/1477","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1477"}],"version-history":[{"count":3,"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=\/wp\/v2\/posts\/1477\/revisions"}],"predecessor-version":[{"id":1482,"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=\/wp\/v2\/posts\/1477\/revisions\/1482"}],"wp:attachment":[{"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1477"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1477"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1477"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}