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	<title>Hack a Day &#187; eric archer</title>
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		<title>Hack a Day &#187; eric archer</title>
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		<title>Bouncing ball analog computer</title>
		<link>http://hackaday.com/2009/01/07/bouncing-ball-analog-computer/</link>
		<comments>http://hackaday.com/2009/01/07/bouncing-ball-analog-computer/#comments</comments>
		<pubDate>Thu, 08 Jan 2009 03:22:50 +0000</pubDate>
		<dc:creator>Eliot</dc:creator>
				<category><![CDATA[misc hacks]]></category>
		<category><![CDATA[analog]]></category>
		<category><![CDATA[analog computer]]></category>
		<category><![CDATA[aphex twin]]></category>
		<category><![CDATA[bouncing ball]]></category>
		<category><![CDATA[eric archer]]></category>
		<category><![CDATA[opamp]]></category>
		<category><![CDATA[oscilloscope]]></category>
		<category><![CDATA[video]]></category>

		<guid isPermaLink="false">http://hackaday.com/?p=7621</guid>
		<description><![CDATA[[Eric Archer] constructed an analog computer to model the physics of a bouncing ball. The core is a TL074 opamp that does all the integral math. He had no trouble finding descriptions of analog computers, but how to set the initial conditions was rarely covered. The controls include potentiometers to set the initial velocity, force [...]<img alt="" border="0" src="http://stats.wordpress.com/b.gif?host=hackaday.com&amp;blog=4779443&amp;post=7621&amp;subd=hackadaycom&amp;ref=&amp;feed=1" width="1" height="1" />]]></description>
			<content:encoded><![CDATA[<p><img class="alignnone size-full wp-image-7622" title="bounce" src="http://hackadaycom.files.wordpress.com/2009/01/bounce.jpg" alt="bounce" width="450" height="303" /></p>
<p>[Eric Archer] constructed an analog computer to <a href="http://ericarcher.net/devices/analog-computer-bouncing-ball/" title="eric archer . net   &raquo; Analog Computer Bouncing Ball">model the physics of a bouncing ball</a>. The core is a TL074 opamp that does all the integral math. He had no trouble finding descriptions of analog computers, but how to set the initial conditions was rarely covered. The controls include potentiometers to set the initial velocity, force of gravity, and coefficient of restitution (how much energy is lost in the bounce). The output is displayed on an oscilloscope. He mentions that this output could be used in electronic music, citing <a href="http://www.last.fm/music/Aphex+Twin/_/Bucephalus+Bouncing+Ball" title="Aphex Twin – Bucephalus Bouncing Ball – Listen free and discover music at Last.fm">Aphex Twin&#8217;s Bucephalus Bouncing Ball</a>. Watch the video below for a demo of all the features.</p>
<p><span id="more-7621"></span></p>
<span style="text-align:center; display: block;"><a href="http://hackaday.com/2009/01/07/bouncing-ball-analog-computer/"><img src="http://img.youtube.com/vi/qt6RVrmvh-o/2.jpg" alt="" /></a></span>
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		<slash:comments>12</slash:comments>
	
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			<media:title type="html">RobotSkirts</media:title>
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		<media:content url="http://hackadaycom.files.wordpress.com/2009/01/bounce.jpg" medium="image">
			<media:title type="html">bounce</media:title>
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