I think it's some kind of radar scanning function that KMF have

It's trying to get a good look at you. For research purposes.

Just think of it like when you rip your foreskin all the way

>>19273286
It's a scanner my dude
Big fancy camera

SCAN MODO

Imagine actually getting a mecha and using it for no other purpose than peeping on people, haha. Asking for a friend, haha.

pretty clear that is scan-radar apparatus.
the reason why he have his own personal armor is because it should be very delicate piece of machinery and thus they put armor on to avoid day to day debris or any environment garbage that may damage it.
but you don't need to have high IQ to think that putting a armor on something like that could come with his own downsides as well that could and probably have show itself in reduction of range and sensible of the sensor if we go by what we saw in the anime.
thus we have that design when they are in fight or normal operation they use it with smaller range of scan because of it's protective armor but we also have the option to open up the armor when you are in a controlled environment and increase the range and probably the sensibility of the sensor, allowing for bigger and better search.

>>19273286
Scans the terrain and probably creates a 3d image of it