The vastly experienced 34-year-old told BBC WM: "You're always looking over your shoulder when the summer comes.
"But I've really enjoyed my football this season and I want to stay in the game as long as I can.
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"It was tough when I first came as I'd not played since April, but I settled in straightaway."
After being released by Bolton Wanderers a year ago, Robinson was without a club when he first joined injury-hit Blues in September 2012 on an initial one-month deal.
But the former Watford, West Bromwich Albion, Bolton and on-loan Leeds United left-back had an outstanding season at St Andrew's, playing all across the back four.
"The lads called me Polyfilla after all the positions I've had to fill in this season," he joked. "God knows what position I'm going to play in next season."
He ended up making 37 appearances, latterly as a makeshift centre-half, alongside his former Albion team-mate Curtis Davies.
"I knew Curt from our days at West Brom together," said Robinson. "He's a fantastic player. It could be tough to keep him this summer."
Robinson's consistent form over the final two months of the campaign was enough to persuade Blues boss Lee Clark that he could release another release another experienced defender, former skipper Gary Caldwell, at the end of the season.
Allied to his dressing room presence, he played a big part in Blues climbing away from the wrong end of the Championship to even briefly flirt as outside play-off contenders before an ultimately respectable top-half finish.
And the work he has done in helping young Mitch Hancox along has hinted at a role on the touchline when his playing days finally come to an end.
"I'm doing my badges at the moment," said Robinson. "When the time is right, I'll be looking for a club to take me on the coaching side."
He becomes the fifth of Blues' out-of-contract players to sign a new deal.
Blues are still waiting on a similar offer to another 34-year-old, midfielder Wade Elliott, born on the same day as Robinson in December 1978.
Defender Jonathan Spector and keeper Colin Doyle, both 27, have been offered two-year contracts.
Scottish winger Chris Burke, 29, has taken up his year's option, while youngsters Akwasi Asante, Amari'i Bell and Will Packwood have all signed new one-year contracts.
Veteran Birmingham City defender Paul Robinson has signed a new 12-month contract, with the option of another year in the club's favour.