Filtering and Estimation of State and Wind Disturbances Aiming Airship Control and Guidance
, José Raul Azinheira 2, André Ricardo Fioravanti 1, Ely Carneiro De Paiva 1,*, José Reginaldo H Carvalho 3 and Ramiro Romankevicius Costa 4
Round 1
Reviewer 1 Report
There are mistakes in sensor modeling. Accelerometers do not measure gravitational acceleration as stated in line 125.
the angular rate measurement coming from the IMU is not just from the body frame (p, q, r), but includes the flexible modes. Failure to consider this phenomenon can perfectly destabilize the desired estimate.
the simulation results must come from a monte-carlo simulation. This is not mentioned by the authors.
no comment is made for the choices of the various gains involved in the simulated algorithms.
Author Response
"Please see the attachment."
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The authors should give more details of how dP measured by the PItot-Static tube is related to the angle formed between the axis of the tube and the air velocity vector.
Author Response
"Please see the attachment."
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Considering only slow movements for the balloon does not make it have dynamics equivalent to a rigid body. Not considering flexibility is a huge modeling error. Unless it is proved that there is no influence on the sensors (what was not done) the conclusions of the study will be invalid.
Author Response
Dear Editors and reviewers,
Please find ATTACHED our letter answering the specific point questioned by reviewer 1, with five new references in the paper to justify our arguments.
I didnt find a link to upload the new version of the paper. However, the only change made now is the inclusion of the paragraph below.
Thank you for your attention,
Prof. Dr. Ely Paiva
"The weights of the diagonal covariance matrix (15 × 15) of the process are shown in Table 6. The gains were chosen empirically, considering that the vehicle has slow dynamics and that the airship can be assumed to be a rigid body. The hypothesis of enough stiffness of the hull is true if we consider that the envelope is under full operational volume and pressure [19–21]. The rigidity assumption of a conventional airship is broken for extremely high speeds or if the envelope is made of thin films to reduce the weight [22,23], which is
not the case of the NOAMAY airship."
Author Response File: Author Response.pdf
Round 3
Reviewer 1 Report
the design must conform to the assumptions. I'm not sure if this is the case.
