Alternate instrument removal

A method of mounting a surgical instrument to a surgical system manipulator and demounting the surgical instrument from the surgical system manipulator, the surgical instrument including an end effector, the manipulator having a holding fixture, the method comprising:

• mounting a surgical instrument assembly to the holding fixture by moving the surgical instrument assembly relative to the holding fixture in a mounting direction to produce a mounted configuration in which the surgical instrument assembly is held by the holding fixture;
• the surgical instrument assembly including the surgical instrument, an interface fitting mounted to a chassis of the surgical instrument, and a securing feature that secures the interface fitting to the chassis;
• in response to binding of the surgical instrument within a surgical site so as to inhibit removal of the end effector from the surgical site:
• operating the securing feature to accommodate demounting of the interface fitting from the chassis;
• demounting the interface fitting from the chassis to produce a demountable configuration in which the chassis is demountable from the holding fixture via movement of the chassis relative to the holding fixture in a demounting direction transverse to the mounting direction;
• and
• demounting the chassis from the holding fixture by moving the chassis in the demounting direction relative to the holding fixture.

A surgical system, comprising:

• a surgical system manipulator comprising a holding fixture;
• and
• a surgical instrument comprising:
• a chassis;
• an end effector coupled with the chassis;
• an interface fitting removably mounted to the chassis;
• and
• a securing feature;
• the chassis and the interface fitting coupled together being a combined assembly;
• the combined assembly being mountable to the holding fixture via movement of the combined assembly relative to the holding fixture in a mounting direction to produce a mounted configuration in which the combined assembly is held by the holding fixture and in which the chassis is in a mounted position and orientation relative to the holding fixture;
• the interface fitting being demountable from both the chassis and the holding fixture, while the chassis is in the mounted position and orientation relative to the holding fixture, to produce a demountable configuration in which the chassis is demountable from the holding fixture via movement of the chassis relative to the holding fixture in a demounting direction transverse to the mounting direction;
• the interface fitting constraining the combined assembly in the mounted configuration from moving in the demounting direction relative to the holding fixture;
• and
• the securing feature configured to be operable to secure the interface fitting to the chassis in the combined assembly and to release the interface fitting from the chassis to accommodate demounting of the interface fitting from both the chassis and the holding fixture.

A surgical instrument, comprising:

• a chassis;
• an end effector coupled with the chassis;
• a securing feature;
• and
• an interface fitting;
• wherein the chassis and the interface fitting are removably secured to each other by the securing feature;
• and
• wherein the surgical instrument is configurable to:
• a mounting configuration of the surgical instrument to a holding fixture of a surgical system manipulator, in which the chassis and the interface fitting are secured to each other by the securing feature and are mountable to the holding fixture by sliding the chassis and the interface fitting in a mounting direction relative to the holding fixture;
• a first dismounting configuration of the surgical instrument from the holding fixture of the surgical system manipulator, in which the chassis and the interface fitting are secured to each other by the securing feature and are demountable from the holding fixture by sliding the chassis and the interface fitting in a direction opposite to the mounting direction relative to the holding fixture;
• and
• a second dismounting configuration of the surgical instrument from the holding fixture of the surgical system manipulator, in which the chassis and the interface fitting are not secured to each other by the securing feature, the interface fitting is demountable from both the chassis and the holding fixture by sliding the interface fitting in the direction opposite to the mounting direction relative to the holding fixture, and with the interface fitting demounted from both the chassis and the holding fixture, the chassis is demountable from the holding fixture by moving the chassis in a direction transverse to the mounting direction relative to the holding fixture.