I have two situations-
A) One, the body with sensor embedded in it kept at rest. B) Second, the body is at rest for 10 secs, then undergoes some movement randomly and comes back to the exact orientation as the initial one (at rest) and kept there for rest for 10 secs again.
In the first case, the quaternion values are constant and that is what is expected. But in the second case, these values from the first 10 secs do not match with the last 10 secs. As the orientation is unchanged in both the situations, how can the quaternion values be different? Also, the accelerometer, gyroscope and magnetometer values for corresponding situations is same.
The sensors which I am using are accelerometer and gyroscope. I dont know the exact way how the quaternion values are getting computed from these sensor values here but I will try to give you a better understanding. So, the quaternion values initially at rest are [1,0,0,0]. If the object is kept at rest, it remains the same (should be like that) but if it moves randomly and then again comes to rest with the exact same orientation as the initial point, the quaternion values are [0.708547,-0.4962,-.4316,-0.2556]. If this is not matching, then what are the absolute quaternion values signifying?
Is there any flaw from my end in understanding the derivation of quaternion values at the conceptual level or I am missing something substantial?