Trajectory control device

A trajectory control device for moving a trajectory tracking member along a trajectory on a workpiece that is placed in an arbitrary position, the trajectory control device comprising:

• a contact sensor configured to contact side surfaces of the workpiece;
• an actuator configured to move the trajectory tracking member and the contact sensor;
• and
• a trajectory controller configured to calculate XY coordinates of the trajectory on the workpiece placed in the arbitrary position, by transforming XY coordinates of the trajectory on the workpiece in a reference position, based on positional information about the side surfaces of the workpiece in the reference position and positional information about the side surfaces of the workpiece placed in the arbitrary position, wherein
• the positional information about the side surfaces of the workpiece placed in the arbitrary position is obtained by the contact sensor.