Dual-Rotor Vtol simulation

Hello all,
Sorry to ask my question here but I really need some help and I can’t manage to ask my question on the gazebo answer part.
I’m trying to create a gazebo model of a vtol with two motors, for this I started from the standard vtol model that I turned and removed two motors. I put you my final results below.

My goal is to make a model much lighter than the standard vtol (1,5 kg instead of 5kg). But this changes the inertia matrix and as I want to use my model with PX4 this one is very important.
I tried to calculate it on meshlab but they tell me that my model is not watertight.
Would someone have another solution to calculate the inertia matrix or has he already worked on this kind of drone and knows the coefficients?
I thank you in advance for your help

Hi there, Gazebo Answers had some downtime during the past days, but it should be back to normal now. Do you mind trying again? That’s the best place for you to get the help you need.