My Fallout 4 is closing by itself when I enter the Machinist's chamber in the Robots mission. What can it be?

One of the "few" bugs in this game.
Right after you open the steel door from inside RobCo, you'll reach a left turn. If you turn your head too much to the left here, the game will just close.
So keep your eyes straight at this point and strafe to the left a short distance until you can proceed further inside the lair.

I don't know if this will solve your problem, but I was having trouble with the texture of a door and it solved mine.

https://steamcommunity.com/app/377160/discussions/0/1741090847736306170/

I don't even know how to thank you, thank you very much in advance. I'll try it here and I'll be back to give feedback. Hehehe Obrigado Fábio, essa dica parece ser mais promissora. Vou tentar aqui!

Thanks man, your tip worked perfectly! I managed to complete the Machinist's mission \o/