Visiting SRI

Stanford Research International (SRI) has had a great role in the development of surgical robotics. First, they developed the Green Telepresence system that was the very first robot to allow remote patient care. The technology was licensed by Intuitive Surgical, and it genarates a great source of revenue through the royalty fees. Later, they developed the light-weight verson of the robot, the M7, around 1998. The system weights only 15 kg, and it is equipped with two 7 DOF arms, motion scaling (max. 1:10), tremor filtering and haptic feedback. The end-effectors can be changed very rapidly, and even a laser tissue welding tool can be mounted on it. The controller has been designed to operate under extremely different atmospheric conditions, therefore it only contains solid-state memory drives. The software of the M7 was updated later to better suit the requirements of teleoperation and communication via Ethernet link. The M7 performed the world’s first automated ultrasound guided tumor biopsy in 2007, and was also used for suturing lacerations of the cornea. SRI developed a very neat master controller and various tools for it. I was given a unique opportunity to visit their facility, guided by Dr. Tom Low, the director of the medical robotics group.

Most of SRI's development was achieved within the frames of the Trauma Pod (TP); Operating room of the future project, which was a "DARPA program to develop a semi-autonomous telerobotic surgical system that could be rapidly deployed and provide critical diagnostic and life-saving interventions in the field.  The footprint was 8ft x 18ft so that it could to fit within an ISO shipment container for ready deployment. The Phase I proof of concept platform was comprised of a da Vinci Classic surgical robot supported by an automated suite of commercially available and custom designed robots. The surgeon remotely controlled the robotic suite to perform representative tasks that included placing a shunt in a simulated blood vessel and performing a bowel anastamosis. The Scrub Nurse Subsystem (SNS) system, developed by Oak Ridge National Laboratory, automatically delivered instruments and supplies to the surgical robot within 10 sec (typically faster than a human). The Tool Rack System (TRS), developed by the University of Washington, held, accepted, and dispensed each of fourteen surgical tools.  The Supply Dispensing System (SDS), developed by General Dynamic Robotic Systems, provided sterile storage, delivery and tracking of standard surgical supplies. The Supervisory Controller System SCS, developed by University of Texas, provided high-level control of all automated subsystems involved in supply dispensing / tool changing and coordinated these functions with the surgical robot.  The Patient Imaging (GE Research) utilized the L-STAT platform to embed CT like capabilities as well as 2-D fluoroscopic data. The User Interface System (UIS) developed by SRI International provided a visual, verbal, aural, and gesture-based interface between the surgeon and TP system.  The visual display consisted of a stereoscopic view of the surgical site augmented by physiologic data, icons and other supporting information.  Results from the Phase I demonstration in 2007 included:

• Automatic storing and dispensing of surgical tools by the TRS with 100% accuracy
• Automatic storing, de-packaging dispensing and counting supplies by the SDS
• Automatic change of surgical tools and delivery and removal of supplies by SNS
• Speech-based interface between a tele-operating surgeon and the system through the UIS
• Automatic coordination and interaction between system components such as the SRS and SNS
• Performing iliac shunt and bowel anastamosis procedures on a phantom by a tele-operated SRS.

Moreover, RST and SRI International joined forces in May 2006 for a first-ever demonstration of unmanned telesurgery involving a robotic surgeon and a robotic scrub technician.  Penelope 3.0 delivered supplies to SRI’s M7 which used them to carry out sponging and suturing of a simulated surgical wound."

"U.S. Army TATRC also funded University of Cincinnati and SRI to explore distributed, automated surgical robotics as a means to augment en route care of injured warfighters. In 2007, the M7 was modified to overcome acceleration and movement routinely encountered during vehicle transport. Three-axis acceleration compensation was developed to dampen turbulence and apply a neutralizing force during periods ofmore constant acceleration.Multiple military personnel, including a U.S. Air Force Critical Care Air Transport (CCAT) surgeon, demonstrated robust performance of the acceleration compensating M7 during parabolic flight aboard NASA’s DC-9 aircraft."

Source: - Broderick et al. "Distributed Automated Medical Robotics to Improve Medical Field Operations"
- Yoo et al. "Military Robotic Combat Casualty Extraction and Care"

More of the M7 robot: H. King et al. “Acceleration compensation for vehicle based telesurgery on earth or in space”.