The long-serving Celtic captain left Parkhead to sign a deal as No.2 to former Hibs colleague Stephen Glass, who took the reins at Pittodrie in March.
Former Scotland midfielder Brown, who turns 36 later this month, will be combining assistant manager duties with a playing role and insists he hasn’t lost his appetite for winning.
Speaking to RedTV as he helped launch the Dons’ new strip, Brown said: “Everyone knows I've been at Celtic for so long, but now it’s a different chapter in my career.
"It’s to help Stephen [Glass] out as well by becoming assistant manager and having a chance to play for Aberdeen as well.
"Aberdeen is a huge club. They have done well over the last few seasons and it’s always been a very, very hard place to come.
"I’m going to enjoy it; I’m sure there will be a few different opinions but I’ve had that all the way through my career and it’s part and parcel of who I am and what I am.
"I’m not always pleasant on the eye but I’ll give 110 per cent. I’m a willing winner and I want to win every game I’m involved in and I think that’s why I came here.
"The challenge is great. I spoke to Dave [Cormack], and Stephen as well. The way they want to play football and push forward is going to be exceptional so we need to make sure we all buy into that and we get some good attacking football at this club.”