A series of questions regarding the usage of 6 DOF integrator and Gyroscope sensor blocks - Aerospace blockset

Greetings mates,

We are designing a small spacecraft, and performing its simulation via Simulink. But during the work, some questions arise regarding the usage of some of the blocks of the Aerospace blockset; our questions are related to the 6 Degree of Freedom integrator and the gyroscope sensor blocks.

Questions regarding 6 DOF integrator:

1 - It is possible to define our body axes as we prefer or they have to be located in the center of mass of the body? As I understand, if we introduce the inertia matrix as an input, we can compute it considering another body-fixed coordinate system than the center of mass (through the Steiner’s theorem), and then the integrator would perform all the analysis in our body-fixed system. Is this right?

2- Considering question 1 is true, all the information obtained from the integrator in the help center of Mathworks is identified as “referred to body frame”, “expressed in body frame”, etc. Would always be our defined body-fixed frame? For example “Euler rotation angles are those between the body and north-east-down (NED) coordinate systems”

3 - Regarding the Vb velocity, as it is not referred to any point, should we consider that is the velocity of the origin of coordinates of our body fixed system?

4 - Where is located the origin of the NED coordinate system? At the same point as our body-fixed frame or at the center of mass? I understand that it will be located following the initial position introduced in terms of longitude, latitude and altitude.

5 - There is a sentence that says “The rotational dynamics of the body defined in a body-fixed frame are given below, where the applied moments are [L M N]T, and the inertia tensor I is with respect to the origin O”. Again, can this origin O be the origin of our body-fixed frame?

6 - Regarding the subscripts, I understand that “b” stands for body, “f” for ECEF and “e” for ECI. Is this correct?

7 - What “Abb” refers to? Is it the acceleration of the body with respect to the ECEF frame (as indicated in output thirteenth), expressed in the body frame?

Then, “Abecef” should be understood as the acceleration of the body, respect to the ECEF frame, expressed in ECEF frame?

8 - The twelfth output refers to “Contains the accelerations in body-fixed axes with respect to body frame”. But, the accelerations at which point? The origin of our body-fixed frame? The center of mass?. Same for output thirdstenth.

9 - The Assumptions and Limitations section says “This implementation assumes that the applied forces are acting at the center of gravity of the body”. Is there any possibility to introduce a drag force for example, knowing that it is applied at the center of pressure of our rigid body?

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Now the questions regarding Gyroscope sensor block:

1 - In the input of the three axis gyroscope it is required to input certain angular rates in rad/s, as shown in the image below. The question is whether these angular rates in body-fixed axis are the ones of the body with respect to an inertial frame (such as ECI, tenth output of the 6DOF ECEF Quaternion) or with respect to a non inertial one (such as the NED frame, ninth output of the 6DOF ECEF Quaternion).

2 - A similar question arises for the other input, G’s, I do not know whether these accelerations are with respect to the body frame (twelfth output of the 6DOF ECEF Quaternion) or with respect to the ECEF (Thirteenth output of the 6DOF ECEF Quaternion)

3 - Then, the angular rates measured as output are the angular rates with respect to the axes of the gyroscope? Or with respect to an inertial reference frame?.

4 - What are exactly the scale factors and cross coupling asked for inside the block? The only similar information I have from the manufacturer of the gyroscope I am modelling is shown in the images below and I do not know how to reshape it into a 3 by 3 matrix as it is needed.

5 - Is the measurement bias of the block what is known as bias instability of the gyroscope?

6 - Regarding the noise performance of the gyroscope, would the noise power needed for the block be the same as the rate noise spectral density shown in the image below?

Thanks for your help!