May one slaughter kosher animals with a machine? I don't mean to ask this question about restraining animals, what I want to know is if one may use a machine to actually make the cut, to actually shecht with a machine.
Yes and no.
Surprisingly, Simlah Chadasha says (siman 7) that you may slaughter with a knife that is attached to a wheel (though only b'dieved, because of a wheel that is not כח אדם; and because it's difficult to do correctly).
However, restrictions apply:
Probably every mass-production kosher company read through these halachos, hoping for a way to make it work -- but the restrictions are too difficult, especially the one about not having the machine attached to the ground. So we still do need shochtim ;).