Endoscope system, endoscope movement control method, and recording medium

An endoscope movement control method for controlling a robotic arm for moving an endoscope, the endoscope comprising an insertion portion extending in a longitudinal axis direction, an imaging sensor disposed at a proximal end of the insertion portion so as to be rotatable about a longitudinal axis, and an optical element that is provided in the insertion portion to tilt an optical axis in a direction offset from the longitudinal axis direction, and the robotic arm holding the endoscope such that the endoscope is rotatable about the longitudinal axis, the endoscope movement control method comprising:

• moving the endoscope in the longitudinal axis direction by the robotic arm;
• detecting a first moving direction of an object in first two images by using the first two images captured by the imaging sensor before and after the movement in the longitudinal axis direction;
• estimating a first amount of rotation of the optical element about the longitudinal axis with respect to the imaging sensor based on the first moving direction;
• moving the endoscope in a direction perpendicular to the longitudinal axis direction by the robotic arm;
• detecting a second moving direction of the object in second two images using two images captured by the imaging sensor before and after the movement in the direction perpendicular to the longitudinal axis direction;
• and
• estimating a second amount of rotation about the longitudinal axis between the robotic arm and the endoscope based on the second moving direction and the first amount of rotation.

A non-transitory computer-readable recording medium in which an endoscope movement control program for controlling a robotic arm for moving an endoscope is stored, the endoscope comprising an insertion portion extending in a longitudinal axis direction, an imaging sensor disposed at a proximal end of the insertion portion so as to be rotatable about a longitudinal axis, and an optical element that is provided in the insertion portion to incline an optical axis in a direction offset from the longitudinal axis direction, the robotic arm holding the endoscope such that the endoscope is rotatable about the longitudinal axis, and the endoscope movement control program causing a computer to:

• move the endoscope in the longitudinal axis direction by the robotic arm;
• detect a first moving direction of an object in first two images by using two images captured by the imaging sensor before and after the movement in the longitudinal axis direction;
• estimate a first amount of rotation of the optical element about the longitudinal axis with respect to the imaging sensor based on the first moving direction;
• move the endoscope in a direction perpendicular to the longitudinal axis direction by the robotic arm;
• detect a second moving direction of the object in the second two images by using the second two images captured by the imaging sensor before and after the movement in the direction perpendicular to the longitudinal axis direction;
• and
• estimate a second amount of rotation about the longitudinal axis between the robotic arm and the endoscope based on the second moving direction and the first amount of rotation.