Talking to reporters this afternoon, Smith said: "It's a challenge, you're talking about playing against teams - particularly a couple of teams, England and France - and physical development that's important, so there's some catching up to do.
"I've been really impressed since I've started, with the attitude of the girls.
"It's a big challenge, but I'm excited. I never thought that at this time in my career I'd be embarking on something new again, and that's what I'm doing."
Whitney Hansen, the daughter of former All Black coach Sir Steve Hansen, and Wesley Clarke will be Smith's assistants.
"Whitney was already with the group as an intern coach, she's highly thought of within the group ... both by players and coaches.
"This is a step up for her, and so she's going to be in charge of the forwards with Mike Cron helping as a mentor - more than mentor, he's going to be here quite a bit leading up to the World Cup.
"So it's a great opportunity, and she's a smart woman who comes across well and has a very good influence on this team of girls."
Former Black Ferns head coach Glenn Moore stepped down following the release of a recent scathing review into the team's culture and environment.
He had coached the Black Ferns since 2015 and was in charge when they won the 2017 World Cup.
Smith's first major coaching role was for the Crusaders in the Super 12 competition in 1997. He coached the Christchurch-based side to two titles in 1998 and 1999 before being appointed All Blacks coach after the 1999 Rugby World Cup.
The Black Ferns defend their World Cup title on home soil later this year.
