So your request is not your saftey approach but only to meet some other requirements which are unknown to us. Is it possible to show all of these requirements?
The quality of an external sensor not only depends on the sensor chip itself but also on the module design and quality. The best sensor will not work best if for example the power design of the board is bad.
Also I didn’t find a parameter to set different rotation values for each imu. So, f this is not possible you must nearly 100% align the external imu with the internal imu in all three axis. But maybe I’d looked correct.
in propulsion, they have specified that a few components are not allowed, like those generic golden-silver motors and generic escs and also generic lipos. fc is of choice, so arducopter pixhawk here. rc needs to be min 250m range so flysky tx meets this.
I also dont know why the added this requirement but it exists
i have written the requirements in the other post.
I think I can align it properly, the remaining rotation thing can be fixed from define in hwdef.
i have used that type of board (601n1) in other fc (inav) which i built in the past and it worked flawlessly without issues, so the board is probably good enough.
Sounds like they’re trying to get folks away from old FCs and force them into something like an H7 FC that already has 2+ IMUs. (or some of the F7s.)
They just didn’t come out and say “no old FC clones”
I would classify buying these old f4 fcs as a mistake too, but I dont have the budget needed to buy a good h7 fc, so I am using it only.
Its not just about imus, its also about the pcb quality, signal wire routing, component quality and much more, and since those fcs are made by brands they are same as long as you buy from a genuine seller.
There is also more work being done on the newer versions so if someone faces issue it is likely to have more easier solution finding