{"id":892,"date":"2011-12-28T01:38:47","date_gmt":"2011-12-27T14:38:47","guid":{"rendered":"http:\/\/www.madox.net\/blog\/?p=892"},"modified":"2011-12-28T01:38:47","modified_gmt":"2011-12-27T14:38:47","slug":"its-a-runaway-succ-failure","status":"publish","type":"post","link":"http:\/\/www.madox.net\/blog\/2011\/12\/28\/its-a-runaway-succ-failure\/","title":{"rendered":"It’s a runaway succ…. failure"},"content":{"rendered":"

Another failure! \u00a0Though all signs pointed to it working…<\/p>\n

So I got a freebie OddBot<\/a>\u00a0sent to me a couple of weeks ago, it basically is a derivative of my Mecanum Rover<\/a>\u00a0and Olaf was kind enough to sent it with almost everything attached less the Chumby<\/a>. \u00a0Since I’ve been on a TI Launchpad<\/a> buying spree, I thought I’ll tack one on in place of the Chumby to drive it.<\/p>\n

So far this post reads like a gigantic spam with all those links…no enlargement links coming up, I promise…just one short video of it not working and running away on me.<\/p>\n

<\/p>\n

So I figured, how hard can it be? \u00a0I procrastinated soldering 2 header pins onto the Launchpad’s TP1 and TP3 tie points for power but after doing that everything was almost recycling :-<\/p>\n

Code – Copied from Madox Kart prototype code and original Rover code…took around 15-30 minutes to copy\/paste and tidy up some comments.
\nCarrier for Launchpad + Battery + \u00a0Breadboard – Almost a direct copy of the Madox Kart prototype again… 15minutes to tweak and 1+ hour to print. \u00a0[Ok 3+ hours, 1+ hour on 0.4mm layers but 3+ hours on 0.2mm layers which I’m a sucker for].<\/p>\n

Everything seemed ‘too easy’ so far, even the code compiled first time which I didn’t believe<\/a>. \u00a0Then the problems started mounting…<\/p>\n

Problem 1 – Cheap mini-USB cables from eBay failed to connect to the Launchpad properly. \u00a0Cable 1 was a complete no go (marked for butchering into a power cable), cable 2 worked only if the connector was held at a particular angle. \u00a0I programmed the Launchpad while keeping my hand steady holding the cable. \u00a0Cheap eBay USB cables, you disappoint me yet again.<\/p>\n

Problem 2 – Connected everything up onto the breadboard and all, no blinky lights on the Launchpad!!! \u00a0Head scratch for a total of ~30 seconds. \u00a0It turns out it is the age old problem of ‘slightly too fat’ AA cells. \u00a0The AA cells are just a bit too wide for the battery holder and because of such, the friction between batteries was stronger than the spring and the + terminal wasn’t making contact. \u00a0Don’t know whether to blame this on the battery holder or the batteries…<\/p>\n

Problem 3 – Continuous rotation servos were not zero’ed, and they were a pain to do so, the slightest adjustment movement will have it spinning the other way. \u00a02 minutes later the zero’ing seems to have been gone, probably due to temperature drift (heating up) – PITA.<\/p>\n

Problem 4 – My favorite – it didn’t work. \u00a0Initially because I didn’t pair the Wii Nunchuk (Duh! moment) and then probably down to the hackity software code \ud83d\ude42 \u00a0The movement matrices seemed wrong and the servo control was very odd, need to debug that later. \u00a0Highlight – IT RAN AWAY ON ME. \u00a0<\/strong>Best illustrated in video form :-<\/p>\n

<\/object><\/p>\n

Problem 4.5 – The wheels haven’t been treated with Plasti-Dip or any other grippy surface, so its still very slippery…<\/p>\n

I’ll upload the code etc when I get around to fixing it…<\/p>\n","protected":false},"excerpt":{"rendered":"

Another failure! \u00a0Though all signs pointed to it working… So I got a freebie OddBot\u00a0sent to me a couple of weeks ago, it basically is a derivative of my Mecanum Rover\u00a0and Olaf was kind enough to sent it with almost everything attached less the Chumby. \u00a0Since I’ve been on a TI Launchpad buying spree, I … Continue reading “It’s a runaway succ…. failure”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-892","post","type-post","status-publish","format-standard","hentry","category-engineering"],"_links":{"self":[{"href":"http:\/\/www.madox.net\/blog\/wp-json\/wp\/v2\/posts\/892","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.madox.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.madox.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.madox.net\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.madox.net\/blog\/wp-json\/wp\/v2\/comments?post=892"}],"version-history":[{"count":11,"href":"http:\/\/www.madox.net\/blog\/wp-json\/wp\/v2\/posts\/892\/revisions"}],"predecessor-version":[{"id":904,"href":"http:\/\/www.madox.net\/blog\/wp-json\/wp\/v2\/posts\/892\/revisions\/904"}],"wp:attachment":[{"href":"http:\/\/www.madox.net\/blog\/wp-json\/wp\/v2\/media?parent=892"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.madox.net\/blog\/wp-json\/wp\/v2\/categories?post=892"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.madox.net\/blog\/wp-json\/wp\/v2\/tags?post=892"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}