Hardware-related security features range from simple to very complex and difficult ones. “Simple” safety features are uncomplicated things such as when the surgeon removes his head from the console (perhaps take a sip of his or her coffee) the camera will cease to move, the instruments will always freeze and the whole system will enter a standby mode (BMJ 2007). An example of a “complex” safety feature is the AESOP endoscope pointing robot (Harvard 2005). The AESOP robot is used for minimally invasive general surgery. The end of the arm of the AESOP is attached to the endoscope through a gimbal and magnetic coupling. Since the incisions in the patient’s body prevents lateral movement of the endoscope tube, the gimbal allows the endoscope tube to pivot about the incision while the robot moves the endoscope tube, in any direction, above the patient (HF issues 2008). This feature makes it, impossible for the endoscope tube to perform lateral movement thus reducing pain to the patient’s body. Harvard 2005 states that another safety feature of the AESOP is the magnetic coupling. This acts as an emergency release. If ever the forces on the endoscope tube exceed the magnetic holding force, the endoscope will disconnect from the arm and will usually fall harmlessly on the patient’s abdomen. Other robotic surgery systems use low-pressure pneumatic power to reduce the dangers of electrical actuation (BMJ 2007). As well, this feature limits the size of the robots workspace in the patient’s body to eliminate the possibility of damage to tissue away from the intended surgical site (Harvard 2005).
There are many software safety features in robotic surgery systems. Most systems use mathematical logic, or algorithms, to control safety features. Ng & Tan, along with other companies, use mathematical logic to analyze the robot’s program flow and determines if it is possible for the control to evade safety features incorporated into the code. It is a completely independent safety monitor that can arrest the servo runway, if it detects anything is abnormal. BMJ 2007 states that such safety features can detect “out-of-safe-boundary” conditions. It is possible to do so by using joint encoder signals (Harvard 2005).
The field of robotic surgery requires many safety features to protect patients ranging from, backup generators to mathematical logic. These safety features can be classified mainly into two distinct categories, hardware-related and software-based (Harvard 2005).
Another software safety feature that is installed in certain systems is a nifty feature in knee surgery systems. It allows the surgeon to control the cutting tools and camera while the robot prevents any motion to occur outside of the designated surgery area (Harvard 2005). This aids the surgeon tremendously because he does not have to worry about movements of the body while he is about to make a very important knot or incision (BMJ 2007).
ROBODOC hip replacement
One final example of safety features in robotic surgery is one that lies in the ROBODOC hip surgery system (Harvard 2005). This feature is basically the opposite of the knee surgery feature. In this safety attribute, the robot moves the cutting tools and camera, while the surgeon is the one who keeps everything under control and monitors the progress.