{"id":44,"date":"2012-04-26T17:19:34","date_gmt":"2012-04-26T17:19:34","guid":{"rendered":"http:\/\/projecthexapod.com\/blog\/?p=44"},"modified":"2012-04-26T17:20:16","modified_gmt":"2012-04-26T17:20:16","slug":"leg-cart-progress","status":"publish","type":"post","link":"http:\/\/projecthexapod.com\/blog\/2012\/04\/leg-cart-progress\/","title":{"rendered":"Leg Cart Progress"},"content":{"rendered":"<p>Well, we just wrapped up our second class session. We kept lecture time pretty short &#8211; we only did a brief introductory presentation on steel weldments (which you can <a href=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/Intro-to-Steel-Fabrication-2012-04-24.pdf\" target=\"_blank\">check out here<\/a>) and reviewed a couple of homework assignments from the first class &#8211; and then spent most of the class on (a) prepping the controls team to work with the upcoming Leg Cart simulation and (b) coordinating the mechanical team&#8217;s build progress. James or Dan will post some simulation videos soon, but in the meantime I thought I&#8217;d show off some of the mechanical work.<\/p>\n<p>To get started, let&#8217;s review the hardware we bought before class, starting with&#8230;<\/p>\n<figure id=\"attachment_45\" aria-describedby=\"caption-attachment-45\" style=\"width: 300px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/IMG_2574.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-45 \" title=\"The Engine\" src=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/IMG_2574-300x200.jpg\" alt=\"\" width=\"300\" height=\"200\" srcset=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/IMG_2574-300x200.jpg 300w, http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/IMG_2574-1024x682.jpg 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-45\" class=\"wp-caption-text\">Our &quot;new&quot;, 135 HP Toyota 2F engine<\/figcaption><\/figure>\n<figure id=\"attachment_46\" aria-describedby=\"caption-attachment-46\" style=\"width: 300px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/GearPump-0001.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-46 \" title=\"Gear Pump\" src=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/GearPump-0001-300x200.jpg\" alt=\"\" width=\"300\" height=\"200\" srcset=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/GearPump-0001-300x200.jpg 300w, http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/GearPump-0001-1024x682.jpg 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-46\" class=\"wp-caption-text\">The pump and driveshaft that match the engine<\/figcaption><\/figure>\n<p>One of the sets of decisions we made as instructors early on was deciding on the powerplant. We needed something that provided sufficient power to provide hydraulic fluid for a 1-2 ton robot, that was (a) robust, (b) relatively affordable, and (c) as off-the-shelf as possible. We decided to rip the hydraulic powerplant out of a forklift (specifically, a Toyota FGC-45 from 1991) and repurpose it. The net result is that we have a 135 horsepower, propane-powered powerplant that produces upwards of 35 gallons per minute of hydraulic fluid at 2,500 psi. The fact that it&#8217;s propane fired means the robot can operate for brief periods indoors, and also means that we can swap industrial-grade fuel tanks good for 6 hours of runtime without having to custom build or fill any of the fuel system components.<\/p>\n<p>So that&#8217;s what we have &#8211; what we&#8217;re working on now is making the <a href=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/LegKart-Isometric.png\" target=\"_blank\">Leg Cart<\/a>, our prototype hydraulics platform. The idea here is to make a platform on &#8220;rails&#8221; (i.e., only able to move in one dimension) that has a single leg and a hydraulic powerplant on board (we&#8217;re borrowing the pump from our full system and running it off of a giant electric motor). This will be the students&#8217; introduction to hydraulic systems, so we&#8217;re building something small (relative to the final system &#8211; the cart will still be 600 pounds&#8230;) at first so we can screw up and figure out what we&#8217;re doing. Without further ado, here&#8217;s the progress we made on the cart chassis in the past week:<\/p>\n<figure id=\"attachment_49\" aria-describedby=\"caption-attachment-49\" style=\"width: 200px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/IMG_2576.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-49\" title=\"Leg Cart Chassis Progress\" src=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/IMG_2576-200x300.jpg\" alt=\"\" width=\"200\" height=\"300\" srcset=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/IMG_2576-200x300.jpg 200w, http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/IMG_2576-682x1024.jpg 682w\" sizes=\"auto, (max-width: 200px) 100vw, 200px\" \/><\/a><figcaption id=\"caption-attachment-49\" class=\"wp-caption-text\">The Leg Cart chassis as of 4\/26\/2012<\/figcaption><\/figure>\n<p>Spark and Mac have been working hard at it for the past week or two &#8211; good work guys! Next up, we have the base weldment for the arm pivot:<\/p>\n<figure id=\"attachment_50\" aria-describedby=\"caption-attachment-50\" style=\"width: 300px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/IMG_2573.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium wp-image-50\" title=\"Base Weldment Progress\" src=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/IMG_2573-300x200.jpg\" alt=\"\" width=\"300\" height=\"200\" srcset=\"http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/IMG_2573-300x200.jpg 300w, http:\/\/projecthexapod.com\/blog\/wp-content\/uploads\/2012\/04\/IMG_2573-1024x682.jpg 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-50\" class=\"wp-caption-text\">Base weldment progress as of 4\/26\/2012<\/figcaption><\/figure>\n<p>Adam and Andy teamed up to work on this over the past week. Unfortunately, some material was backordered, but we&#8217;ll be resolving that shortly.<\/p>\n<p>Joel, Joe, Mike and Jona are all working on parts that are heavy on machining and low on welding, so we&#8217;ll see updates from them a bit later on in the process.<\/p>\n<p>That&#8217;s it for now. Keep an eye out for an update on simulations!<\/p>\n<p>-Gui<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Well, we just wrapped up our second class session. We kept lecture time pretty short &#8211; we only did a brief introductory presentation on steel weldments (which you can check out here) and reviewed a couple of homework assignments from the first class &#8211; and then spent most of the class on (a) prepping the &hellip; <a href=\"http:\/\/projecthexapod.com\/blog\/2012\/04\/leg-cart-progress\/\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Leg Cart Progress<\/span><\/a><\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":["post-44","post","type-post","status-publish","format-standard","hentry","category-class-update"],"_links":{"self":[{"href":"http:\/\/projecthexapod.com\/blog\/wp-json\/wp\/v2\/posts\/44","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/projecthexapod.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/projecthexapod.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/projecthexapod.com\/blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"http:\/\/projecthexapod.com\/blog\/wp-json\/wp\/v2\/comments?post=44"}],"version-history":[{"count":7,"href":"http:\/\/projecthexapod.com\/blog\/wp-json\/wp\/v2\/posts\/44\/revisions"}],"predecessor-version":[{"id":55,"href":"http:\/\/projecthexapod.com\/blog\/wp-json\/wp\/v2\/posts\/44\/revisions\/55"}],"wp:attachment":[{"href":"http:\/\/projecthexapod.com\/blog\/wp-json\/wp\/v2\/media?parent=44"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/projecthexapod.com\/blog\/wp-json\/wp\/v2\/categories?post=44"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/projecthexapod.com\/blog\/wp-json\/wp\/v2\/tags?post=44"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}