In an apparatus, a coordinate obtaining unit drives a robot to move a camera opposing a workpiece in a first direction such that the workpiece is captured in an FOV of the camera. The coordinate obtaining unit obtains second and third coordinates of a preset point of the robot arm in respective second and third axes of a three-dimensional coordinate system with the workpiece being captured in the FOV. The first, second, and third coordinates are defined as coordinates of a temporally defined reference point of the workpiece in the three-dimensional coordinate system. A pose determining unit drives, at a given timing, the robot arm to determine a pose of the preset point based on a positional relationship between the first, second, and third coordinates of the temporally defined reference point of the workpiece and actual coordinates of the preset point of the robot arm.