Robot arm apparatus and calibration method

A calibration method, comprising:

• in a medical arm system comprising an arm unit and an imaging unit attachable to the arm unit, the arm unit comprising a plurality of links joined by at least one joint unit, and the imaging unit configured to capture an image of a surgical field:
• acquiring internal model information;
• and
• updating an internal model based on the internal model information, wherein
• the internal model is used to drive the medical arm system,
• the internal model information is acquired in a state in which the imaging unit pointed at a specific point on a jig attachable to the arm unit as a reference point in a real space, and
• the internal model information comprises first geometric information of the arm unit, second geometric information of the jig attachable to the arm unit, and focus position information of the imaging unit.

A non-transitory computer-readable medium having stored thereon, computer-executable instructions, which when executed by a computer, cause the computer to execute operations, the operations comprising:

• in a medical arm system comprising an arm unit and an imaging unit attachable to the arm unit, the arm unit comprising a plurality of links joined by at least one joint unit, and the imaging unit configured to capture an image of a surgical field:
• acquiring internal model information;
• and
• updating an internal model based on the internal model information, wherein
• the internal model is used to drive the medical arm system,
• the internal model information is acquired in a state in which the imaging unit is pointed at a specific point on a jig attachable to the arm unit as a reference point in a real space, and
• the internal model information comprises first geometric information of the arm unit, second geometric information of the jig attachable to the arm unit, and focus position information of the imaging unit.