{"id":13140,"date":"2018-03-26T13:26:56","date_gmt":"2018-03-26T02:26:56","guid":{"rendered":"http:\/\/legoeng.local\/?p=13140"},"modified":"2019-03-26T18:28:21","modified_gmt":"2019-03-26T07:28:21","slug":"diy-walkers-klanns-mechanical-spider","status":"publish","type":"post","link":"http:\/\/legoeng.local\/diy-walkers-klanns-mechanical-spider\/","title":{"rendered":"DIY Walkers: Klann&#8217;s Mechanical Spider"},"content":{"rendered":"<p>This creation is a LEGO-based version of Klann&#8217;s Mechanical Spider, which makes use of one of the best known walking mechanisms, the Klann linkage. The Klann linkage was designed by mechanical engineer Joe Klann and is very sturdy.<\/p>\n<figure id=\"attachment_13141\" aria-describedby=\"caption-attachment-13141\" style=\"width: 300px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/legoeng.local\/wp-content\/uploads\/2018\/03\/IMG_0835.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-13141 size-medium\" src=\"http:\/\/legoeng.local\/wp-content\/uploads\/2018\/03\/IMG_0835-300x225.jpg\" alt=\"\" width=\"300\" height=\"225\" srcset=\"http:\/\/legoeng.local\/wp-content\/uploads\/2018\/03\/IMG_0835-300x225.jpg 300w, http:\/\/legoeng.local\/wp-content\/uploads\/2018\/03\/IMG_0835-768x576.jpg 768w, http:\/\/legoeng.local\/wp-content\/uploads\/2018\/03\/IMG_0835.jpg 1024w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-13141\" class=\"wp-caption-text\">An EV3 version of Klann&#8217;s Mechanical Spider<\/figcaption><\/figure>\n<p>Several large creations based on Klann&#8217;s linkage have appeared at the annual <a href=\"https:\/\/burningman.org\/\" target=\"_blank\" rel=\"noopener\">Burning Man festival<\/a>, including a 7 ton version built by MoltenSteelMan:<\/p>\n<p><iframe loading=\"lazy\" title=\"Burning Man 2010 - The Beast Spider Walker\" width=\"500\" height=\"375\" src=\"https:\/\/www.youtube.com\/embed\/B3fqNVr1LLc?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen><\/iframe><\/p>\n<p>There were two main challenges in creating our design: approximating Klann&#8217;s linkage in LEGO and achieving consistent foot speed.<\/p>\n<h2>Challenge 1: Approximating Klann&#8217;s linkage in LEGO<\/h2>\n<p>Walking machine linkages can be modified to produce different types of foot paths.<\/p>\n<p>A foot path is the way in which the part of the walking linkage in contact with the ground moves.<\/p>\n<p>Desirable characteristics of foot paths are:<\/p>\n<ul>\n<li>A high percentage of foot contact with the ground per axle rotation. (Represented by the flat, lower part of the dotted foot path in the below video).<\/li>\n<li>Consistent foot-speed while in contact with the ground, so that the feet don\u2019t skid or shake the machine (Represented by the density of dots, high density = slow, low density = high, in the below video).<\/li>\n<li>The ability to &#8220;step&#8221; reasonably high to walk on rugged terrain (Represented by the height of the dotted foot path in the below video).<\/li>\n<\/ul>\n<p>I was able to do a simple optimization of the Klann linkage by creating a simulator of Klann\u2019s linkage in the computer program Scratch.<\/p>\n<p><a href=\"https:\/\/www.diywalkers.com\/klann-linkage-optimizer.html\" target=\"_blank\" rel=\"noopener\">You can use this simulator to create your own customized Klann linkages here.<\/a><\/p>\n<p>Scratch allowed me to adjust the mechanism\u2019s bar lengths by integer numbers to find a combination that created an optimal foot path in LEGO.<\/p>\n<p><iframe loading=\"lazy\" title=\"Klann Linkage Optimizer\" width=\"500\" height=\"375\" src=\"https:\/\/www.youtube.com\/embed\/7hENmWD0yoQ?start=1&#038;feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen><\/iframe><\/p>\n<h2>Challenge 2: Achieving consistent foot speed<\/h2>\n<p>Even with a linkage optimizer, it is still difficult achieve consistent foot speed with Klann\u2019s linkage. This isn\u2019t an issue when on smooth surfaces, as the feet can slide. When on rough terrain, however, the increased traction of each foot causes Klann to lurch, as seen below:<\/p>\n<p><a href=\"http:\/\/legoeng.local\/wp-content\/uploads\/2018\/03\/Klann-Robot-Shaking-1-1.gif\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-13230 size-full\" src=\"http:\/\/legoeng.local\/wp-content\/uploads\/2018\/03\/Klann-Robot-Shaking-1-1.gif\" alt=\"\" width=\"440\" height=\"247\" \/><\/a><\/p>\n<p>How does one go about solving this? One way to stabilize the foot speed is to add rotating feet, decreasing the traction of each foot, which dampens the lurching effect.<\/p>\n<p>You can see this solution implemented in this video.<\/p>\n<p><iframe loading=\"lazy\" title=\"Smoothing Klann&#039;s Speed with Feet that Rotate\" width=\"500\" height=\"281\" src=\"https:\/\/www.youtube.com\/embed\/16Dn6Jij99I?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen><\/iframe><\/p>\n<p>Finally, here\u2019s our latest version of Klann, which incorporates the linkage optimized in Scratch along with longer legs so that the EV3 brick can be mounted underneath Klann\u2019s frame.<\/p>\n<p><a href=\"http:\/\/legoeng.local\/wp-content\/uploads\/2018\/03\/IMG_0747.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-13143 size-medium\" src=\"http:\/\/legoeng.local\/wp-content\/uploads\/2018\/03\/IMG_0747-300x225.jpg\" alt=\"\" width=\"300\" height=\"225\" srcset=\"http:\/\/legoeng.local\/wp-content\/uploads\/2018\/03\/IMG_0747-300x225.jpg 300w, http:\/\/legoeng.local\/wp-content\/uploads\/2018\/03\/IMG_0747-768x576.jpg 768w, http:\/\/legoeng.local\/wp-content\/uploads\/2018\/03\/IMG_0747.jpg 1024w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p>Note that this version does not have rotating feet. You\u2019re encouraged to add them, or to come up with your own solution if you want to improve performance on terrain that has traction.<\/p>\n<p><iframe loading=\"lazy\" title=\"Klann&#039;s Spider - Mindstorms Long Legs\" width=\"500\" height=\"281\" src=\"https:\/\/www.youtube.com\/embed\/9BJrf4ADpc0?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen><\/iframe><\/p>\n<p>For more information, visit\u00a0<a href=\"https:\/\/www.diywalkers.com\/klanns-spider-ev3-long-legs.html\" target=\"_blank\" rel=\"noopener\">Klann&#8217;s Mechanical Spider with Longer Legs (Ver 3)<\/a>\u00a0 at\u00a0<a href=\"http:\/\/www.diywalkers.com\/\">www.DIYwalkers.com<\/a>. If you decide to build your own, please let us know.<\/p>\n<p>&nbsp;<\/p>\n<div class=\"also-in-this-series\">\n<h3 class=\"series-title\">Also in <q>DIY Walkers<\/q><\/h3>\n<ol start=\"1\">\n<li class=\"series-post\">\n\t\t\t<a href=\"http:\/\/legoeng.local\/diy-walkers-explorations-of-the-trotbot-walking-mechanism\/\" title=\"DIY Walkers: The TrotBot walking mechanism\">DIY Walkers: The TrotBot walking mechanism<\/a>\n\t\t<\/li>\n<li class=\"series-post\">\n\t\t\t<a href=\"http:\/\/legoeng.local\/diy-walkers-trotbot-using-ev3\/\" title=\"DIY Walkers: TrotBot using EV3\">DIY Walkers: TrotBot using EV3<\/a>\n\t\t<\/li>\n<li class=\"series-post\">\n\t\t\t<a href=\"http:\/\/legoeng.local\/diy-walkers-strider\/\" title=\"DIY Walkers: Strider\">DIY Walkers: Strider<\/a>\n\t\t<\/li>\n<li class=\"series-post\">\n\t\t\t<a href=\"http:\/\/legoeng.local\/ev3-trotbot-version-2-inspired-by-a-galloping-horse\/\" title=\"EV3 TrotBot Version 2: Inspired by a Galloping Horse\">EV3 TrotBot Version 2: Inspired by a Galloping Horse<\/a>\n\t\t<\/li>\n<li class=\"series-post\">\n\t\t\t<a href=\"http:\/\/legoeng.local\/hexapod-trotbot-a-classroom-friendly-diy-walker\/\" title=\"Hexapod TrotBot: A classroom-friendly DIY walker\">Hexapod TrotBot: A classroom-friendly DIY walker<\/a>\n\t\t<\/li>\n<li class=\"series-post\">\n\t\t\t<a href=\"http:\/\/legoeng.local\/diy-walkers-klanns-mechanical-spider\/\" title=\"DIY Walkers: Klann&#8217;s Mechanical Spider\">DIY Walkers: Klann&#8217;s Mechanical Spider<\/a>\n\t\t<\/li>\n<li class=\"series-post\">\n\t\t\t<a href=\"http:\/\/legoeng.local\/rapidly-prototyping-strider-ver-3-to-be-smoother-stronger-faster\/\" title=\"Rapidly Prototyping Strider &#8211; Smoother, Stronger, Faster\">Rapidly Prototyping Strider &#8211; Smoother, Stronger, Faster<\/a>\n\t\t<\/li>\n<li class=\"series-post\">\n\t\t\t<a href=\"http:\/\/legoeng.local\/linkage-warm-ups-1\/\" title=\"Linkage Warm Ups 1: LEGO Punchers and the 4-Bar Linkage\">Linkage Warm Ups 1: LEGO Punchers and the 4-Bar Linkage<\/a>\n\t\t<\/li>\n<li class=\"series-post\">\n\t\t\t<a href=\"http:\/\/legoeng.local\/linkage-warm-ups-2-lego-jumpers-and-hoppers\/\" title=\"Linkage Warm Ups 2: LEGO Jumpers and Hoppers\">Linkage Warm Ups 2: LEGO Jumpers and Hoppers<\/a>\n\t\t<\/li>\n<\/ol>\n<p><a href=\"http:\/\/legoeng.local\/series\/diy-walkers\/\">View the entire series<\/a><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>This creation is a LEGO-based version of Klann&#8217;s Mechanical Spider, which makes use of one of the best known walking mechanisms, the Klann linkage. The Klann linkage was designed by mechanical engineer Joe Klann and is very sturdy. Several large creations based on Klann&#8217;s linkage have appeared at the annual Burning Man festival, including a [&hellip;]<\/p>\n","protected":false},"author":591,"featured_media":13143,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[99,8,502],"tags":[],"_links":{"self":[{"href":"http:\/\/legoeng.local\/wp-json\/wp\/v2\/posts\/13140"}],"collection":[{"href":"http:\/\/legoeng.local\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/legoeng.local\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/legoeng.local\/wp-json\/wp\/v2\/users\/591"}],"replies":[{"embeddable":true,"href":"http:\/\/legoeng.local\/wp-json\/wp\/v2\/comments?post=13140"}],"version-history":[{"count":0,"href":"http:\/\/legoeng.local\/wp-json\/wp\/v2\/posts\/13140\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/legoeng.local\/wp-json\/wp\/v2\/media\/13143"}],"wp:attachment":[{"href":"http:\/\/legoeng.local\/wp-json\/wp\/v2\/media?parent=13140"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/legoeng.local\/wp-json\/wp\/v2\/categories?post=13140"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/legoeng.local\/wp-json\/wp\/v2\/tags?post=13140"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}