{"id":154,"date":"2008-03-22T05:31:13","date_gmt":"2008-03-22T09:31:13","guid":{"rendered":"http:\/\/www.etotheipiplusone.net\/?p=154"},"modified":"2008-03-22T05:48:39","modified_gmt":"2008-03-22T09:48:39","slug":"media-lab-shenanigans-continued","status":"publish","type":"post","link":"https:\/\/www.etotheipiplusone.net\/?p=154","title":{"rendered":"Media Lab Shenanigans continued"},"content":{"rendered":"<p>Even though neither the <a href=\"\/pics\/4-wheeler-whole.jpg\">omnidirectional 4WD vehicle<\/a> nor the <a href=\"http:\/\/cities.media.mit.edu\/projects\/scooter.html\" target=\"_blank\">Roboscooter<\/a> are my own projects, per se, I still feel like taking a bunch of pictures and writing about their development as Media Lab Sponsors Week approaches, especially since I&#8217;m pretty heavily involved in the R&amp;D.<\/p>\n<p>And of course I feel like showing off all the shiny toys. Here&#8217;s some stuff from today.<\/p>\n<p style=\"text-align: center\"><a href=\"\/pics\/ml5.jpg\" title=\"If these are lifepo cells, are conventional ones deadpos?\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.etotheipiplusone.net\/pics\/ml5_mid.jpg\" height=\"384\" width=\"512\" \/><\/a><\/p>\n<p>40AH large-scale rectangular <a href=\"http:\/\/en.wikipedia.org\/wiki\/Lithium_iron_phosphate_battery\" target=\"_blank\">LiFePO4<\/a> cells. Yes, this is one cell. It&#8217;s roughly the size of a construction brick, but a little flatter. 3.2 volts per cell. These are from Thunder Sky, which is a big enough name in the R\/C hobby world to make me consider them legit.<\/p>\n<p>The 4-wheeler will use one 48v(15S)  pack for drive and one 24V (7S? 8S? 7.5S?!) pack for steering and the rest of the electrical system.<\/p>\n<p style=\"text-align: center\"><a href=\"\/pics\/ml6.jpg\" title=\"What would you do with a 1000w soldering iron?\"><img decoding=\"async\" src=\"https:\/\/www.etotheipiplusone.net\/pics\/ml6_mid.jpg\" \/><\/a><\/p>\n<p>Packs under construction. The shipment of cells came with a bucket of formed copper battery bars that mounted to the terminals with screws. Handy, since nobody had to wield a kilowatt soldering iron.<\/p>\n<p style=\"text-align: center\"><a href=\"\/pics\/ml7.jpg\" title=\"I *PROMISE* this is not the chassis to an Unlimited Class bot.\"><img decoding=\"async\" src=\"https:\/\/www.etotheipiplusone.net\/pics\/ml7_mid.jpg\" \/><\/a><\/p>\n<p>The chassis hasn&#8217;t changed much from last week, but that will not be the case soon.<\/p>\n<p style=\"text-align: center\"><a href=\"\/pics\/ml10.jpg\" title=\"Kit. Car.\"><img decoding=\"async\" src=\"https:\/\/www.etotheipiplusone.net\/pics\/ml10_mid.jpg\" \/><\/a><\/p>\n<p>Some waterjet-cut aluminum plate that will be eventually assembled into the steering arms and motor mounts. I love this method of construction and will probably be using it more in my own stuff &#8211; that is, 2D plates cut with slots and keys that assemble puzzle-like into a 3D shape, which is then retained by screws.  With a 5-axis nozzle, I&#8217;m sure we could make even weirder shapes.<\/p>\n<p style=\"text-align: center\"><a href=\"\/pics\/ml8.jpg\" title=\"Damn Asians all look alike....\"><img decoding=\"async\" src=\"https:\/\/www.etotheipiplusone.net\/pics\/ml8_mid.jpg\" \/><\/a><\/p>\n<p>Here&#8217;s a shot of the (mostly) functional scooter in folded form. No, that&#8217;s not me fiddling with it.<\/p>\n<p>When folded, the scooter is strangely aesthetic in a way, like someone in various yoga positions. It has a strangely organic yet still very mechanical look. But now I&#8217;m getting too artsy. The parking stand is only a mockup at the moment, as the above picture shows. A hardc\u00c3\u00b8re metal stand will be made for the presentations.<\/p>\n<p>There&#8217;s been both mechanical and electrical work on the thing done, since some parts weren&#8217;t made to spec or weren&#8217;t there at all (Hey, how much moving does it need to do at a show? None!). I&#8217;ve been working on a closed-loop controller for the folding process as well as doing some fabrication work.<\/p>\n<p style=\"text-align: center\"><img decoding=\"async\" src=\"\/pics\/ml9_mid.jpg\" \/><\/p>\n<p>Like this. This is the main seat folding control link. The 4-bar linkage which folds the seat in sync with the chassis was made with some links too long (I think it was a revision control issue). Fortunately, they were too long, becuase they could be shortened. The process was to slit each link, mill a bit off each end, then recombine them with a &#8220;connector block&#8221;. The links are C-channel in profile, so making this block was simple.<\/p>\n<p>I also discovered that having the depth stop on the drill press work with your countersink is a wonderful thing. Those are the best countersunk holes I&#8217;ve made to date.<\/p>\n<p>So, what on earth am I working on anyways? Well, sort of both projects at once. I&#8217;ve been rather general purpose, building whatever needs building, but focusing somewhat on the electronics. This is great, since I get the best of all the worlds involved, but get to work on a field which I don&#8217;t have as much experience in.<\/p>\n<p>The whole of spring break will probably be filled with build pics, so stay tuned!<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Even though neither the omnidirectional 4WD vehicle nor the Roboscooter are my own projects, per se, I still feel like taking a bunch of pictures and writing about their development as Media Lab Sponsors Week approaches, especially since I&#8217;m pretty heavily involved in the R&amp;D. And of course I feel like showing off all the [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8,1],"tags":[40,46,44,42,43],"class_list":["post-154","post","type-post","status-publish","format-standard","hentry","category-mit-boston","category-stuff","tag-electric-scooter","tag-electric-vehicle","tag-media-lab","tag-mit","tag-smart-cities"],"_links":{"self":[{"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=\/wp\/v2\/posts\/154","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=154"}],"version-history":[{"count":0,"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=\/wp\/v2\/posts\/154\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=154"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=154"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.etotheipiplusone.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=154"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}