<blockquote style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;" class="gmail_quote"><blockquote>--------- Forwarded message ----------<br>From: Gabriel Ambuehl <<a href="mailto:gabriel_ambuehl@buz.ch">
gabriel_ambuehl@buz.ch</a>><br>To: <a href="mailto:community@lists.openmoko.org">community@lists.openmoko.org</a><br>Date: Fri, 26 Jan 2007 19:13:49 +0100<br>Subject: Re: idea for Neo 2nd generation: Accelerometer<br>On Friday 26 January 2007 18:41:50 Tim Newsom wrote:
<br>> > yes, accelerometers measure acceleration. The first derivative of<br>> > acceleration is velocity.<br>> Ok Steve. I grant you that the first derivative of acceleration is<br>> velocity...<br><br>
I don't think so. The first derivative of VELOCITY is acceleration (i.e.<br>integrate acceleration to get velocity as acceleration is the rate of change<br>of velocity) if my high school physics doesn't totally fail me right now.
<br><br>This also means that if acceleration is zero, velocity simply is constant. And<br>in order to have velocity >0 you must have encountered some acceleration at<br>some point.<br></blockquote></blockquote><br><br>
Wow, I can't believe I got that backwards, thanks for the correction. Kind of embarrassing considering I actually work on this stuff. However, it doesn't invalidate that you don't need any more information than the accelerometer and a starting point in order to track velocity and position. I'm going to go work on removing the foot I shoved so far into my mouth earlier.
<br><br>--Steve<br>