Core Motion Framework issue about device distance form time1 to time2

[ccko]

Hello,

i want to get device distance (x, y, z separately) from time1 to time2

can I get the result from coreMotion( MotionUpdate or accelerometer)?

I can get CMRotationMatrix, attitude.

but i don't know how to use it to meet my need.

is there any document for this kind of issue?

thanks for your help.

Regards