Imaging device for calculating three-dimensional position on the basis of image captured by visual sensor

An imaging device, comprising:

• a vision sensor configured to capture a two-dimensional image of a target object;
• and
• a processor configured to
• detect a focus position where the vision sensor is focused;
• set a parameter for calculating a three-dimensional position corresponding to a specific position in the two-dimensional image captured by the vision sensor;
• store, in a memory, setting information for setting the parameter corresponding to the focus position;
• detect a predetermined feature portion in the two-dimensional image of the target object;
• and
• calculate a three-dimensional position of the predetermined feature portion by using the parameter, wherein
• the vision sensor is a single two-dimensional camera,
• a distance from the target object to the vision sensor is predetermined and maintained at a predetermined value,
• the processor is configured to calculate the three-dimensional position of the predetermined feature portion based on the specific position of the predetermined feature portion in the two-dimensional image by using a camera model and the distance from the target object to the vision sensor,
• the camera model includes an extrinsic parameter and an intrinsic parameter, and
• the processor is configured to calculate the intrinsic parameter included in the camera model based on the focus position and the setting information.