Hi Robert,
  Thank you for your reply.  Are you suggesting to only use the gyro and forget about the accelerator?  how about the Freescale accelerator?  Is it noisy too?  Thanks!

Robert Rolf <Robert.Rolf@ualberta.ca> wrote:
  The accelerometer signal needs to be differentiated to get
velocity. The ADXL signals are quite noisy so you are better
off having a direct velocity signal from a gyro, particularly if
using PID control.
Robert

James James wrote:

> Hi everyone,
> 
> I am thinking to build something like the nBot from
> David:
> http://www.geology.smu.edu/~dpa-www/robo/nbot/
> 
> I think it would be very cool to put the Feedback
> Control Theory I learned to practice. I am currently
> gathering information/parts to build the robot. 
> Anyways, I have few questions:
> 
> 1. Isn't the accelerator alone enough? I mean all
> you need to know are how fast the robot is tilting and
> the current tilt angle, right? Couldn't the
> accelerator alone do all that?
> 
> 2. What's the role of the gyroscope? I understand
> that the output voltage change of the gyro is
> proportional to the speed or rate of the tilt angle. 
> Isn't it the same as what the accelerator does?
> 
> I am refering to the DXRS150 gyro and the
> ADXL203/MMA7260 accelerators.
> 
> Best regards,
> James
> 
> 
> 
> 
> 
> __________________________________ 
> Yahoo! FareChase: Search multiple travel sites in one click.
> http://farechase.yahoo.com
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist

  

		
---------------------------------
 Yahoo! FareChase - Search multiple travel sites in one click.  
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist