Grip strength with tactile feedback for robotic surgery

Details Grip strength with tactile feedback for robotic surgery Grip strength with tactile feedback for robotic surgery

2000-04-06

2003-07-15

Cuchlinski, Jr., William A. (Department: 3661)

Data processing: generic control systems or specific application

Specific application, apparatus or process

Robot control

C700S213000, C700S245000, C700S248000, C700S251000, C700S253000, C700S257000, C700S259000, C700S261000, C700S262000, C606S130000, C606S139000, C606S142000, C606S206000, C606S208000, C606S170000, C600S102000, C600S109000, C600S117000, C600S118000, C600S587000, C600S103000, C318S568110, C318S568130, C318S568160, C318S568200, C318S568220

Reexamination Certificate

active

06594552

ABSTRACT:

BACKGROUND OF THE INVENTION
The present invention is related to medical devices, systems, and methods, and is also relevant to robotic devices, systems, and methods for their use in medical and other robotic applications. In one embodiment, the invention provides a grip actuation system within a master/slave robot arrangement to give a system operator tactile feedback of grip strength when gripping small objects.
Minimally invasive surgical techniques are intended to reduce the amount of an extraneous tissue which is damaged during diagnostic or surgical procedures. By reducing the trauma to surrounding tissues, patient recovery time, discomfort, and deleterious side effects can be reduced. While many surgeries are performed each year in the United States, and although many of these surgeries could potentially be performed in a minimally invasive manner, only a relatively small percentage of surgeries currently use the new minimally invasive techniques now being developed. This may be in part due to limitations in minimally invasive surgical instruments and techniques, as well as the additional surgical training involved in mastering these techniques.
While known minimally invasive surgical techniques hold great promise, there are significant disadvantages which have, to date, limited the applications for these promising techniques. For example, the standard laparoscopic instruments used in many minimally invasive procedures do not provide the surgeon the flexibility of tool placement found in open surgery. Additionally, manipulation of delicate and sensitive tissues can be difficult while manipulating these long-handled tools from outside the body. Many surgical procedures are complicated by the limited access provided to the surgical site, in which tools and viewing scopes are often inserted through narrow cannulae, all while viewing the procedure in a monitor which is often positioned at a significantly different angle than the patient.
To overcome these disadvantages, minimally invasive telesurgical systems are now being developed. These systems will increase a surgeon's dexterity and effectiveness within constrained internal surgical sites. In a robotic surgery system, an image of the surgical site can be displayed adjacent master input devices. The system operator will manually manipulate these input devices, thereby controlling the motion of robotic surgical instruments. A servomechanism will generally move surgical end effectors in response to the operator's manipulation of the input devices, ideally providing translation, rotation, and grip actuation modes. As the servomechanism moves the surgical end effectors in response to movement of the input devices, the system operator retains control over the surgical procedure. The servomechanism may move the devices in position and orientation, and a processor of the servomechanism can transform the inputs from the system operator so that the end effector movements, as displayed to the system operator at the master control station, follow the position and orientation of the input devices as perceived by the system operator. This provides the system operator with a sense of “telepresence” at the internal surgical site.
The robotic surgical systems now being developed show tremendous promise for increasing the number and types of surgeries which may be performed in a minimally invasive manner. Nonetheless, these known systems could benefit from still further improvements. For example, although force feedback systems for robotic surgery have been proposed, the added cost and complexity of these proposed force feedback systems has often limited their implementation. Additionally, work in connection with the present invention has shown that known force reflecting master/slave robotic arrangements without force sensors may not be ideal for implementation of tactile feedback to the system operator in all the actuation modes within a telesurgical system, particularly in grip.
In light of the above, it would be desirable to provide improved surgical devices, systems, and methods. It would also be desirable to provide improved robotic devices, systems, and methods, both for use in robotic surgical systems and other robotic applications. It would be beneficial if these improvements enhanced the operator's control over, and tactile feedback from, the robotic end effectors. It would further be desirable if these improvements did not unnecessarily complicate the system, and if these improved techniques recognized differences between grip and other actuation modes that might justify specialized grip systems.
SUMMARY OF THE INVENTION
The present invention provides improved robotic devices, systems, and methods, particularly for use in telesurgical systems. In general, the invention provides an improved master/slave arrangement for enhanced telepresence, particularly for grip actuation within a multiple degree of freedom telepresence system. By applying the present invention, slave grip strength can be enhanced and/or tailored when master grip elements approach their closed configuration, rather than relying on gripping forces which are only a function of position error.
The invention provides an enhanced sense of feel by using a programmable grip strength amplification, generally without having to resort to slave force sensors. Instead, a grip error signal can be artificially altered beginning at a predetermined grip configuration. For example, where a grip input handle includes first and second grip members that move relative to each other to define a variable grip separation, and where an end effector similarly includes first and second elements defining a variable end effector separation, when above a predetermined grip separation, actuation of the grip members will preferably result in one-to-one corresponding actuation of end effector elements. This allows, for example, a robotic surgical system operator to change the separation angle of the jaws of a surgical forceps by corresponding changes to a separation angle of an input handle. In many embodiments, contact between the elements of the forceps may begin just as the gripping members pass the predetermined grip member separation (assuming the jaws are free to move with negligible tissue or other matter between the jaw elements). Continuing to squeeze the grip members beyond this predetermined point can quickly impose the maximum allowable gripping force on the jaws, thereby allowing the jaws to squeeze very small or thin objects such as sutures, tissue membranes, and the like, without having to push the grip members to an unnatural angle. In the exemplary embodiment, a biasing spring assembly may be provided between the grip members, with the grip members beginning to compress the spring assembly just as they pass the predetermined grip enhancement point. This provides tactile feedback to the robotic system operator indicating that the enhanced grip strength is being applied, and can simulate the resilient deflection of handles (such as the handles of a medical forceps or hemostat) felt when squeezing a small object using a traditional surgical tool.
In a first aspect, the invention provides a method comprising squeezing first and second grip members together with a hand of an operator. First and second end effector elements are moved in response to the squeezing of the grip members according to a control relationship. The control relationship is altered when the grip members are near a closed configuration.
The end effectors will often be moved by applying following forces in response to a misalignment between a grip separation (between grip members) and an end effector separation (between end effector elements). The separations may comprise angles, linear distances, vectors, or the like. In an exemplary embodiment, the moving step can be effected by measuring separations between the grip members and between the instrument elements. The end effector elements can then be moved by producing an error signal from a comparison between the measured grip separation and the

Affiliated with

Also associated with

Rating

Grip strength with tactile feedback for robotic surgery does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Grip strength with tactile feedback for robotic surgery, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Grip strength with tactile feedback for robotic surgery will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3045040