The former Liverpool defender, who moved from Nottingham Forest to the Blades today on a two-and-a-half-year deal, will start out providing back-up on the left.
Current occupier of that role, Enda Stevens, has been one of United's most consistent players sicne moving to the club but there is little in the way of cover.
Robinson’s United career is expected to begin as a challege to Stevens but Wilder says the 26-year-old ‘isn't there to make up the numbers’.
"Jack's got a great pedigree and he will make our squad stronger,” he said.
"But he isn't just coming in to make the numbers up, it's a specific position in our system and we feel he is the best option for us at this time.
"Jack can comfortably play in a couple of roles and we're delighted to add him to the group. He's got a fantastic attitude and he's ambitious to earn a place in the team."
Robinson become United’s second signing of the transfer window, with the former England under 21 international joining fellow defender Jack Rodwell at the Lane, following his surprise arrival earlier this month.
United's activity is not expected to be finished with that. They have been linked with central defenders, central midfielder and forwards already during this window.