The Republic of Ireland Under-21 international, who is 21, has agreed a deal until January 2 and could make his debut at Preston on Saturday.
Manager Uwe Rosler told the club website: "Rob is a player who I know, one who has been with us before. We had him here last summer and he has made big strides at Wigan since then.
"He has been on loan to Burton and now (Latics boss) Roberto Martinez and everybody at Wigan think he is ready for the next step. We have been looking for somebody who has the qualities that Rob has, and that is why we have brought him in.
"I know what Rob is about and I have already seen him in training.
"I have got a good relationship with Roberto Martinez and we have been following Rob closely, not just now when we have been trying to get him but for a long time. We never really lost contact, I was always asking after Rob."