ADAPTER CONFIGURED TO MAINTAIN A SURGICAL TOOL IN A PREDETERMINED POSE WHEN DISCONNECTED FROM DRIVE UNIT

A surgical tool configured to selectively connect to a drive unit includes an elongate shaft, an end effector, an adapter, and first, second, third, and fourth cables. The end effector includes a first and second jaws. The cables extend through the elongate shaft with a distal portion of the first and fourth cables secured to a first side of the first and second jaws, respectively, and a distal portion of the second and third cables secured to a second side of the first and second jaws, respectively. The adapter is configured to selectively connect to the drive unit and includes a differential drive mechanism configured to manipulate proximal portions of the cables which manipulate the end effector in pitch, yaw, and jaw DOFs. Each of the cables are biased proximally and configured to maintain the end effector in a desired pose when the tool is disconnected from the drive unit.