The present invention generally provides improved surgical and/or robotic devices, systems, and methods.
Minimally invasive medical techniques are aimed at reducing the amount of tissue which is damaged during diagnostic or surgical procedures, thereby reducing patient recovery time, discomfort, and deleterious side effects. Millions of “open” or traditional surgeries are performed each year in the United States; many of these surgeries can potentially be performed in a minimally invasive manner. However, only a relatively small number of surgeries concurrently use minimally invasive techniques due to limitations in minimally invasive surgical instruments and techniques and the additional surgical training required to master them.
Minimally invasive telesurgical systems for use in surgery are being developed to increase a surgeon's dexterity as well as to allow a surgeon to operate on a patient from a remote location. Telesurgery is a general term for surgical systems where the surgeon uses some form of remote control, e.g., a servomechanism, or the like, to manipulate surgical instrument movements rather than directly holding and moving the instruments by hand. In such a telesurgery system, the surgeon is provided with an image of the surgical site at the remote location. While viewing typically a three-dimensional image of the surgical site on a suitable viewer or display, the surgeon performs the surgical procedures on the patient by manipulating master control input devices, which in turn control the motion of robotic instruments. The robotic surgical instruments can be inserted through small, minimally invasive surgical apertures to treat tissues at surgical sites within the patient, often the trauma associated with accessing for open surgery. These robotic systems can move the working ends of the surgical instruments with sufficient dexterity to perform quite intricate surgical tasks, often by pivoting shafts of the instruments at the minimally invasive aperture, sliding of the shaft axially through the aperture, rotating of the shaft within the aperture, and/or the like.
The servomechanism used for telesurgery will often accept input from two master controllers (one for each of the surgeon's hands) and may include two or more robotic arms or manipulators. Mapping of the hand movements to the image of the robotic instruments displayed by the image capture device can help provide the surgeon with accurate control over the instruments associated with each hand. In many surgical robotic systems, one or more additional robotic manipulator arms are included for moving an endoscope or other image capture device, additional surgical instruments, or the like.
A variety of structural arrangements can be used to support the surgical instrument at the surgical site during robotic surgery. The driven linkage or “slave” is often called a robotic surgical manipulator, and example linkage arrangements for use as a robotic surgical manipulator during minimally invasive robotic surgery are described in U.S. Pat. Nos. 6,758,843; 6,246,200; and 5,800,423, the full disclosures of which are incorporated herein by reference. These linkages often make use of a parallelogram arrangement to hold an instrument having a shaft. Such a manipulator structure can constrain movement of the instrument so that the instrument shaft pivots about a remote center of spherical rotation positioned in space along the length of the rigid shaft. By aligning this center of rotation with the incision point to the internal surgical site (for example, with a trocar or cannula at an abdominal wall during laparoscopic surgery), an end effector of the surgical instrument can be positioned safely by moving the proximal end of the shaft using the manipulator linkage without imposing potentially dangerous forces against the abdominal wall. Alternative manipulator structures are described, for example, in U.S. Pat. Nos. 6,702,805; 6,676,669; 5,855,583; 5,808,665; 5,445,166; and 5,184,601, the full disclosures of which are incorporated herein by reference.
While the new robotic surgical systems and devices have proven highly effective and advantageous, still further improvements would be desirable. For example, when moving the surgical instruments within a minimally invasive surgical site, robotic surgical manipulators may exhibit a significant amount of movement outside the patient, particularly when pivoting instruments about minimally invasive apertures through large angular ranges, which can lead to the moving manipulators inadvertently coming into contact with each other, with instrument carts or other structures in the surgical room, with surgical personnel, and/or with the outer surface of the patient. In particular, the manipulator arm near a distal instrument may inadvertently contact the outer patient surface as the manipulator pivots about the minimally invasive aperture. Alternative highly configurable “software center” surgical manipulator systems have been proposed and may provide significant advantages, but may also present different challenges. In particular, the proposed software center systems may not have all the safety advantages of the mechanically constrained remote-center linkages in some conditions. Regardless, as the range of surgeries being performed using telesurgical systems continues to expand, there is an increasing demand for expanding the available configurations and the range of motion of the instruments within the patient. Unfortunately, both of these changes can increase the challenges associated with controlling and predicting the motion of the manipulators outside the body, and increase the importance of avoiding undesirable contact or collision between components of the manipulator arm and an outer surface of the patient.
For these and other reasons, it would be advantageous to provide improved devices, systems, and methods for surgery, robotic surgery, and other robotic applications. It would be particularly beneficial if these improved technologies provided the ability to avoid collisions between the manipulator arm and the patient while maintaining a desired end effector state or a desired location of a remote center about which the instrument shaft pivots. Ideally, these improvements would allow for improved movement of one or more manipulator arms during a surgical procedure while avoiding collisions between the manipulator arms and the patient during end effector movement. Additionally, it would be desirable to provide such improvements while increasing the range of motion of the instruments for at least some procedures and without significantly increasing the size, mechanical complexity, or costs of these systems, and while maintaining or improving their dexterity.