{"id":164,"date":"2012-11-23T16:21:39","date_gmt":"2012-11-23T23:21:39","guid":{"rendered":"http:\/\/www.meanboyfriend.com\/overdue\/?p=164"},"modified":"2012-11-30T05:51:27","modified_gmt":"2012-11-30T12:51:27","slug":"arduino-powered-dinosaur","status":"publish","type":"post","link":"http:\/\/www.meanboyfriend.com\/overdue\/2012\/11\/arduino-powered-dinosaur\/","title":{"rendered":"Arduino powered dinosaur"},"content":{"rendered":"

Bryn’s recent 5th birthday brought with it an extremely cool Dinosaur toy (available from Maplins<\/a> in the UK). It consisted of a set of cleverly engineered cardboard cutouts which you fold and join to make a T-Rex, coupled with a motor, cogs, wires, battery box, switch and plastic stick, which all join together to make the cardboard T-Rex move and gnash it’s teeth when you’ve put it all together.<\/p>\n

Bryn and I built it (although to be honest the cardboard folding\/joining was pretty fiddly, and while he pushed the motor, battery box etc. in the base confidently, I had to do most of the construction of the cardboard model. The result was much much better than I really expected. The dinosaur moved (on the spot) and it’s teeth gnashed pretty effectively – enough for Bryn to play a game of putting his finger near it’s mouth and getting ‘bitten’.<\/p>\n

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The next day, I had an idea that if the dinosaur’s motor could be driven off our arduino, we could wire the dinosaur up. I asked Bryn, if he’d like to do this as a project and he was keen, so the next day we sat down to do this.<\/p>\n

The most recent project we’d done with the arduino had been using a light sensitive resistor to detect light levels and switch an LED on\/off, so making the dinosaur light activated seemed an obvious way to go. I got the basic motor circuit design out (details at\u00a0http:\/\/www.oomlout.com\/oom.php\/products\/ardx\/circ-03<\/a>) and started to try to work out how wire the photo-resistor.<\/p>\n

While I was doing this, I was pretty impressed that Bryn just got on and wired up the motor circuit from the diagram pinned to the breadboard. While I had to put the more fiddly components in, all the wires Bryn did without prompting or help.<\/p>\n

I was able to wire up the photo-resistor separately on the same breadboard (using\u00a0http:\/\/www.oomlout.com\/oom.php\/products\/ardx\/circ-09) – including (at Bryn’s request) an LED also to be controlled by light levels. I have to admit it took me a little while to work out the wiring, and this led me to just write the code to run the circuit without really getting Bryn to help – which I was sorry about afterwards.<\/p>\n

I’d got some concerns about whether the arduino board would drive the motor OK, as I hadn’t been able to establish what voltage\/current was required for the motor. The circuit above uses a transistor to enable the arduino to drive a small toy motor, but I wasn’t sure if it would be enough for the dinosaurs motor (which usually runs off two AA batteries).<\/p>\n

We covered the photo-resistor – and success. The dinosaur leapt (if slightly lethargically as the motor clearly not quite getting the power it really needed) to life. A dinosaur that comes to life when you switch the lights off!<\/p>\n

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I guess the next step would be to get some LEDs on wires to push through the cardboard as eyes, and some sound effects …<\/p>\n","protected":false},"excerpt":{"rendered":"

Bryn’s recent 5th birthday brought with it an extremely cool Dinosaur toy (available from Maplins in the UK). It consisted of a set of cleverly engineered cardboard cutouts which you fold and join to make a T-Rex, coupled with a motor, cogs, wires, battery box, switch and plastic stick, which all join together to make…<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[1],"tags":[7,8,9],"class_list":["post-164","post","type-post","status-publish","format-standard","hentry","category-uncategorized","tag-arduino","tag-coding","tag-codingforkids"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"http:\/\/www.meanboyfriend.com\/overdue\/wp-json\/wp\/v2\/posts\/164","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.meanboyfriend.com\/overdue\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.meanboyfriend.com\/overdue\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.meanboyfriend.com\/overdue\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/www.meanboyfriend.com\/overdue\/wp-json\/wp\/v2\/comments?post=164"}],"version-history":[{"count":7,"href":"http:\/\/www.meanboyfriend.com\/overdue\/wp-json\/wp\/v2\/posts\/164\/revisions"}],"predecessor-version":[{"id":171,"href":"http:\/\/www.meanboyfriend.com\/overdue\/wp-json\/wp\/v2\/posts\/164\/revisions\/171"}],"wp:attachment":[{"href":"http:\/\/www.meanboyfriend.com\/overdue\/wp-json\/wp\/v2\/media?parent=164"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.meanboyfriend.com\/overdue\/wp-json\/wp\/v2\/categories?post=164"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.meanboyfriend.com\/overdue\/wp-json\/wp\/v2\/tags?post=164"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}