Accelerometer on RC Car — Parallax Forums

# Accelerometer on RC Car

Posts: 1,919
edited 2010-05-06 09:08
The attached "Smart Sensors Excerpt - RC Car.pdf" demonstrates techniques for datalogging an RC car's acceleration with the MX2125 accelerometer and transferring those measurements from the Debug Terminal to a Microsoft Excel spreadsheet.· Once in·the spreadsheet, the measurements can be substituted into v = v0 + at and·x = x0 + v0t + 1/2at2 to reconstruct the car's velocity and position.· Over the eight second test segment graphed in the spreadsheet, the position graph turned out to be remarkably accurate.· The MS Excel spreadsheet is attached as "Spreadsheet - Acceleration Velocity Position Data and Graphs.zip".· Three screen captures are also attached that show acceleration, velocity and position plots.

Post Edited (Andy Lindsay (Parallax)) : 5/1/2006 6:31:12 PM GMT

• Posts: 1,919
edited 2006-05-01 18:44
Attached is DatalogAcceleration.bs2, the program used to collect the RC car's accleration samples.· Also attached is "Smart Sensors - Datalogging Acceleration.pdf", which is used to test the program before mounting the board on the car.

Post Edited (Andy Lindsay (Parallax)) : 5/1/2006 6:57:03 PM GMT
• Posts: 109
edited 2006-05-19 09:45
Can you explain the formula v = v0 + at and x = x0 + v0t + 1/2at2 And a little more on velocity from acceleration.
I need to find the velocity of a rocket from the acceleration.
Here is the StampDAQ spreedsheet I have come up with so far.
I'm having a little trouble getting velocity and distance traveled. Any suggestions would be great.
• Posts: 1,919
edited 2006-05-19 17:16
Mike,

A revised version of the RC Car PDF with equation explanations is attached: Smart Sensors Excerpt - Rc Car (Revised).pdf··

Also, try downloading the spreadsheet where I graphed the RC car acceleration and examine the equations in the cells.· Here's a link to the earlier post with the spreadsheet: Spreadsheet - Acceleration Velocity Position Data and Graphs.zip

Andy
• Posts: 109
edited 2006-05-20 19:30
Thanks that was very helpful!
• Posts: 1
edited 2010-05-06 09:08
That is quite helpful...
Thank you for sharing this with us....

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BORROWS
• Posts: 1
x = (x MIN 1875 MAX 3125) - 1875 ** 10538

where does the 10538 come from? The doc on accelerometer had only -127 for scaling. Also the pdf with equations (not first) does not read for me.
Thanks
• Posts: 12,366
edited 2017-10-30 14:19
Welcome to the forums!

I'm trying to get the author of this thread to repost the pdf, and maybe answer your question.