Flexible tube insertion apparatus, insertion control apparatus, and flexible tube insertion method

An insertion control apparatus comprising:

• a processor comprising hardware, the processor being configured to:
• control a stiffness of each of various portions of a flexible tube configured to be inserted into a tract of a target;
• detect occurrence of a buckling in the flexible tube;
• detect that a pulling operation of the flexible tube is performed, after detecting the occurrence of the buckling;
• store position information of a stiffness-to-be-enhanced portion including a portion of the flexible tube adjacent to a buckling portion of the flexible tube and located on a distal side of the buckling portion, and
• increase a stiffness of the stiffness-to-be-enhanced portion, based on the position information stored in the storage device, when the pulling operation is detected.

A flexible tube insertion method comprising:

• controlling a stiffness of each of various portions of a flexible tube to be inserted into a tract of a target;
• detecting occurrence of a buckling in the flexible tube;
• detecting that a pulling operation of the flexible tube is performed, after detecting the occurrence of the buckling;
• storing position information of a stiffness-to-be-enhanced portion including a portion of the flexible tube adjacent to a buckling portion of the flexible tube and located on a distal side of the buckling portion;
• and
• increasing a stiffness of the stiffness-to-be-enhanced portion, based on the stored position information, when detecting the pulling operation.

A flexible tube insertion method comprising:

• inserting a flexible tube into a tract of a target, the flexible tube including stiffness changing devices arranged along a longitudinal axis of the flexible tube;
• performing a pulling operation of the flexible tube after a buckling occurs in the flexible tube;
• and
• increasing a stiffness of a stiffness changing device that is located at a stiffness-to-be-enhanced portion including a portion of the flexible tube adjacent to a buckling portion of the flexible tube and located on a distal side of the buckling portion, after the pulling operation is performed.