A system and method of registering a surgical table and a computer-assisted device includes an articulated arm and a control unit coupled to the articulated arm. The articulated arm has a distally mounted instrument configured to be inserted into a patient at a body opening. The control unit is configured to detect a first motion of a surgical table coupled to the control unit via a communications connection. The first motion of the surgical table causes a corresponding second motion of a control point of the articulated arm. The control unit is further configured to determine a first angular direction of the first motion in a surgical table coordinate frame, determine a second angular direction of the second motion in a computer-assisted medical device coordinate frame, and determine a third angular relationship between the surgical table and the computer-assisted medical device based on the first and second angular directions.
