The Surgical Assistant Workstation (SAW) provides a software framework, written in C++, that enables the integration of new research with a telesurgical robot system such as the daVinci. Although the daVinci System (with its research interface) was a primary motivator, the SAW framework contains a generic robot interface and can therefore be used with other robot systems. The framework does not rely on stereo video or a stereo display, but some functionality is not available if only a mono video and/or display is available.
The SAW framework provides the capability to integrate patient models (such as those based on preoperative images) and intraoperative imaging (such as ultrasound) within the video display of a telesurgical robot system. A real-time data pipeline processes the feedback, which is mostly video but includes other data such as robot positions. The video is rendered on the display, possibly with image fusion and/or overlay of patient models or intraoperative images, as described below. The framework supports the use of the "master" manipulators to interact with the graphical objects rendered within the display (e.g., as "6 degree-of-freedom mice"). Other components include registration methods that can be used to co-register the different information sources, such as stereo video, patient models, and laparoscopic ultrasound. The interface supports overlay of registered patient models (with adjustable transparency) onto the stereo display, as well as the manipulation of unregistered models (e.g., the ability to view CT cross-sections). Laparoscopic ultrasound images appear on a 2D plane that is correctly positioned within the 3D view; this registration is achieved by a tool tracking module that uses a combination of robot position feedback and visual tracking.