Excuse me If you don't feel that this question is good enough, but at the moment this is my level of entry knowledge.
Imagine that you have 200 recordings from the sensors, and information that you have are linear acceleration on X, Y, Z axis and angular velocity for the X, Y, Z axis.
How could I interpret this data to gain more information, if I also have orientation in quaternions?
Could I somehow get a disposition from this information, is there a way to use DFT that is other than removing noise?
Is there a way maybe to find out how much power or energy was spent while moving?
Also, note that you don't know the time interval, between that 200 points of data.