Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: vidam on January 26, 2008, 07:30:32 AM

Title: Accelerometer Use
Post by: vidam on January 26, 2008, 07:30:32 AM
Dimension Engineering has a 3D Accelerometer which I would like to experiment on using for velocity controlling a robot on different terrain type hills, flat and so forth. Is this a good use for an accelerometer?

http://www.dimensionengineering.com/DE-ACCM3D.htm

Title: Re: Accelerometer Use
Post by: vidam on January 26, 2008, 09:19:17 AM
I just found Admin's tutorial on accelerometers: http://www.societyofrobots.com/sensors_accelerometer.shtml
Is it just me but I see no mention of controlling motor speed with an accelerometer by taking the square root of acceleration and you get the velocity of the robot right?
Title: Re: Accelerometer Use
Post by: paulstreats on January 26, 2008, 09:28:44 AM
not exactly.
if you get an initaial reading of say 4m/s, as your robot starts moving along say the x axis, this reading should become less and less until it is 0 m/s, at this point your robot is moving at 4m/s but has stopped accelerating
Title: Re: Accelerometer Use
Post by: Admin on January 26, 2008, 04:45:44 PM
Quote
using for velocity controlling a robot on different terrain type hills
how will your accelerometer know the difference between robot acceleration and the gravity vector? it can't . . .

you will need other sensors . . . an IMU actually . . .
Title: Re: Accelerometer Use
Post by: vidam on January 26, 2008, 07:01:24 PM
This is not what I would like to hear. An IMU means more $$$. :-/
Title: Re: Accelerometer Use
Post by: SmAsH on January 26, 2008, 08:37:51 PM
yea well thats what you get for choosing robotics for a hobby. $_$

~smash