The control device includes a target setter that sets the target travel distance of the driving object in every predetermined period when the driving object is moved, and an operation amount determiner that determines whether or not the operation amount calculated by the operation amount calculator is equal to or more than a predetermined upper limit. The target setter sets the target travel distance according to a first rule when the operation amount is determined by the operation amount determiner to be less than the upper limit. When the operation amount is determined to be equal to or more than the upper limit by the operation amount determiner, the target setter sets according to a second rule.