Aspects of a control system of a minimally invasive surgical apparatus

Abstract

A surgical method and a control system can be used in a minimally invasive surgical apparatus. The method includes generating a desired surgical instrument movement command signal. It further includes comparing the desired surgical instrument movement command signal with at least one preset surgical instrument movement limitation. Should the desired surgical instrument command signal transgress the preset surgical instrument movement limitation, the desired surgical instrument movement command signal is restricted to yield a restricted surgical instrument movement command signal. A surgical instrument is then caused to move in response to the restricted surgical instrument movement command signal. The method further provides for haptic feedback on a master control in response to restriction of the desired surgical instrument movement command signal.

Description

BACKGROUND OF THE INVENTION Minimally invasive medical techniques are aimed at reducing the amount of extraneous tissue which is damaged during diagnostic or surgical procedures, thereby reducing patient recovery time, discomfort, and deleterious side effects. Millions of 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 currently use these techniques due to limitations in minimally invasive surgical instruments and techniques and the additional surgical training required to master them. Advances in minimally invasive surgical technology could dramatically increase the number of surgeries performed in a minimally invasive manner. The average length of a hospital stay for a standard surgery is significantly longer than the average length for the equivalent surgery performed in a minimally invasive surgical manner. Thus, the complete adoptio...

AI Technical Summary

Benefits of technology

In accordance with another aspect of the invention, there is provided a method of effecting control between a master and a slave of a minimally invasive surgical apparatus, the method including generating slave movement commands in response to and corresponding with master movement; inputting the slave movement commands into a simulated domain, the simulated domain having at least one preset movement limitation; determining whether or not the slave movement command transgresses the movement limitation in the simulated domain; restricting the slave movement command in the simulated domain, if it transgresses the limitation, by a value calculated to yield a restricted slave movement command not transgressing the movement limitation; forwarding the restricted slave movement command to the slave to cause the slave to move in sympathy with the restricted slave movement command; and causing a master movement command, corresponding to the value by which the slave movement command was restricted, to be sent to the master to cause the master to resist movement promoting corresponding slave movement commands which transgress the slave movement limitation set in the simulated domain.

Problems solved by technology

However, only a relatively small number of surgeries currently use these techniques due to limitations in minimally invasive surgical instruments and techniques and the additional surgical training required to master them.

Thus, the complete adoption of minimally invasive techniques could save millions of hospital days, and consequently millions of dollars annually in hospital residency costs alone.

There are many disadvantages relating to current minimally invasive surgical (MIS) technology.

For example, existing MIS instruments deny the surgeon the flexibility of tool placement found in open surgery.

Most current laparoscopic tools have rigid shafts and difficulty is experienced in approaching the surgical site through the small incision.

Additionally, the length and construction of many surgical instruments reduces the surgeon's ability to feel forces exerted by tissues and organs on the end effector of the associated tool.

The lack of dexterity and sensitivity of surgical tools is a major impediment to the expansion of minimally invasive surgery.

Unfortunately, robotic arms often have responsive limitations which may be more restrictive than the controller.

Furthermore, the robotic arm joints often have limits in their displacement capability or range of achievable position relative to each other.

Yet further, the robotic arm and surgical instrument assemblies may have positional limits beyond which it is not possible to move.

One such obstacle is constraining master control movement input within bounds dictated by mechanically achievable positional movements and velocity of its associated arm and surgical instrument assembly.

Images