Sort of a computer-animated riff on Back to the Future, Robinsons follows a young orphan named Lewis who flits among the past, present and future in search of his parents. The movie underwent an overhaul after Pixar founder John Lasseter took over as animation chief at Walt Disney Pictures, and it still feels like a project in flux. There are enough smart and funny moments, though, most of which involve the inept villain and his artificially intelligent hat. Whenever these two are on the screen scheming and bickering like an oddball, villainous comedy team, the movie offers clear evidence of Pixar’s trademark wit.