Hi, Please could someone explain how they think an accelerometer would work if positioned within the center of a freely rotating sphere (e.g a kicked football)? If using triple axis accelerometer and the ball was kicked from a standstill but with no spin, I would imagine that the accelerometer would give the linear acceleration in the X,Y and Z axis. Is this correct? What would then happen if the ball was kicked with an amount of spin? Would the accelerometer readings be meaningless due to the change in orientation of the sensor due to the spin? Also, would it be possible to determine the spin rate/axis using some form of accelerometer configuration? Any help would be most appreciated. Many Thanks. Andy.