A controller calculates a correction amount of a position of a robot 1 at a movement point in a first movement path, and drives the robot 1 in a second movement path obtained by correcting the first movement path. The controller includes a second camera configured to detect a shape of a part after a robot apparatus performs a task, and a variable calculating unit configured to calculate, based on an output of the second camera, a quality variable representing quality of a workpiece. When the quality variable deviates from a predetermined determination range, a determination unit of the controller determines that the position or an orientation of the robot 1 needs to be modified based on a correlation between the correction amount of the position in the first movement path and the quality variable.