Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: o0tsubasa0o on April 08, 2010, 12:49:00 AM

Title: need help with this graph
Post by: o0tsubasa0o on April 08, 2010, 12:49:00 AM
I have given a task by my teacher to use a Crossbow CXL04GP3 Accelerometer to measure the tilt when it is mount on a SUMO Robot .

By using the Hyper terminal to record the readings ( when the SUMO moves and stop ) and the transfer it to microsoft excel to plot a line graph .

the readings is -> Tilt value x:50944 , i will use the list of the readings to plot the graph .
 
Graph :
(http://i283.photobucket.com/albums/kk309/o0tsubasa0o/untitled.jpg)

this is a pitch graph isnt it ? . erm the Y axis is the data and what does the X axis represents ? and how do i see the tilt from this graph ?

Kinda new to this things would anyone help me out thx
Title: Re: need help with this graph
Post by: nottoooily on April 08, 2010, 02:56:19 AM
Should be 2.4V at 0g and 3.4V/1.4V at 1g. So you need to scale the ADC output.

Unless the robot is also converting it to an angle you'll have to do that yourself.

Angle from vertical = cos^-1(acceleration/g)

Assuming it's not actually accelerating.
Title: Re: need help with this graph
Post by: waltr on April 08, 2010, 08:15:36 AM
Quote
what does the X axis represents
time
Title: Re: need help with this graph
Post by: o0tsubasa0o on April 08, 2010, 06:21:12 PM
thx for the help :) to the both of you