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[on:]

Hello,
Has anybody got any experience with gryo and accelerometer sensors?  I'm wondering how fast the errors accumulate when calculating relative-position by dead-reckoning.  For example, if a rover equipped with one of these sensors sets off to do a lap of a room, how near could it get to its starting point after (say) a minute?

[Reply #1 on:]

I don't have any experience with your parts, but I was recently looking into the issue - which isn't technically "dead reckoning", but more "inertial navigation":

http://en.wikipedia.org/wiki/Inertial_navigation_system

Note the graph at the top - note how poor the accuracy is compared to say, D/GPS...

With that said, I am sure those numbers have to do with actual vehicles (airplanes and/or missles/rockets - most likely) in real-world conditions over large distances. A robot in a room with a perfectly flat floor (and little wheel slipage) would likely fair better. But as soon as you start adding other needs (carpeted floor, irregular surfaces, etc) - navigational accuracy likely goes down quickly...

[Reply #2 on:]

Yes, sorry, I used completely the wrong term.  Inertial positioning is what I should have said.

What I have in mind is double-integrating the 3D acceleration to get position, assuming the sensor does not rotate.  Then I'd like to remove the rotation constraint by incorporating readings from a gyro.

The specs for reasonably-priced sensors seem amazingly good, but of course the errors will grow enormously once integrated over time.  The 650m/hr figure on Wikipedia is discouraging.