John Brown, the current incumbent, has given Knox a wide-ranging scouting role in an effort to enhance the squad as they push for a return to the SPFL Premiership.
Knox, who has also been assistant manager at Manchester United and Aberdeen, has not worked since leaving Pittodrie last season but Brown is delighted to see him return to Tayside.
"Archie has done it all in football. I have great respect for him and he's one I can trust 100%," he said. "He has far too much experience not to be doing anything in football. So I felt Archie's wealth of contacts would be invaluable. I've asked him to come in a role which would develop the squad, identifying what we need to strengthen."