METHODS FOR MAXIMUM TORQUE DRIVING OF ROBOTIC SURGICAL TOOLS

• US 20130110130A1
• Filed: 11/13/2012
• Published: 05/02/2013
• Est. Priority Date: 06/30/2003
• Status: Active Grant

• Current Assignee: Nitish Swarup, Scott Manzo
• Original Assignee: Nitish Swarup, Scott Manzo
• Inventors: MANZO, SCOTT, SWARUP, NITISH
• Granted Patent: US 9,014,856 B2
• Time in Patent Office: Days
• US Class Current: 606/130
• CPC Class Codes: A61B 1/00149 using articulated arms
• CPC Class Codes: A61B 2017/00203 with speech control or speech recognition
• CPC Class Codes: A61B 2017/00477 Coupling A61B2017/0046 takes precedence
• CPC Class Codes: A61B 2017/00482 with a code
• CPC Class Codes: A61B 2017/2825 Inserts of different material in jaws
• CPC Class Codes: A61B 2017/2829 with a removable cover
• CPC Class Codes: A61B 2017/2929 with a head rotatable about the longitudinal axis of the shaft
• CPC Class Codes: A61B 2017/2932 Transmission of forces to jaw members
• CPC Class Codes: A61B 2034/305 Details of wrist mechanisms at distal ends of robotic arms
• CPC Class Codes: A61B 2034/715 Cable tensioning mechanisms for removing slack
• CPC Class Codes: A61B 2090/031 torque limiting
• CPC Class Codes: A61B 2090/064 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61B 34/30 Surgical robots
• CPC Class Codes: A61B 34/37 Master-slave robots A61B34/35 takes precedence
• CPC Class Codes: A61B 34/71 Manipulators operated by drive cable mechanisms
• CPC Class Codes: A61B 34/74 Manipulators with manual electric input means
• CPC Class Codes: A61B 34/76 Manipulators having means for providing feel, e.g. force or tactile feedback
• CPC Class Codes: A61B 90/361 Image-producing devices, e.g. surgical cameras
• CPC Class Codes: A61B 90/98 using electromagnetic means, e.g. transponders
• CPC Class Codes: B25J 9/1689 Teleoperation
• CPC Class Codes: G05B 2219/40144 : Force sensation feedback from slave
• CPC Class Codes: G05B 2219/42289 : Avoid overload servo motor, actuator limit servo torque
• CPC Class Codes: G05B 2219/45123 : Electrogoniometer, neuronavigator, medical robot used by surgeon to operate
• CPC Class Codes: G16H 20/40 : relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture
• CPC Class Codes: G16H 40/63 : for local operation
• CPC Class Codes: Y10S 901/02 : Arm motion controller
• CPC Class Codes: Y10S 901/19 : Drive system for arm
• CPC Class Codes: Y10S 901/21 : Flaccid drive element

Abstract

In one embodiment of the invention, a control system for a robotic surgical instrument is provided including a torque saturation limiter, a torque to current converter coupled to the torque saturation limiter, and a motor coupled to the torque to current converter. The torque saturation limiter receives a desired torque signal for one or more end effectors and limits the desired torque to a range between an upper torque limit and a lower torque limit generating a bounded torque signal. The torque to current converter transforms a torque signal into a current signal. The motor drives an end effector of one or more end effectors to the bounded torque signal in response to the first current signal.

Claims

1-13. -13. (canceled)

14. A method for a robotic surgical instrument comprising:

limiting a desired torque to a range between an upper torque limit and a lower torque limit;

transforming the desired torque into a first current signal; and

driving a first end effector to the limited desired torque in response to the first current signal.

15. The method of claim 14, further comprising:

prior to driving the first end effector, requesting a control system to position the first end effector at a negative angle with respect to a second end effector, the second end effector rotatably coupled to the first end effector at a first axis.

16. The method of claim 14, further comprising:

prior to driving the first end effector, transforming the desired torque into the first current signal and a second current signal; and

driving the first end effector and a second end effector to the desired torque in response to the first current signal and the second current signal, respectively.

17. The method of claim 14, wherein

in transforming the desired torque, the desired torque is split and transformed into the first current signal and the second current signal,

18. A method for a robotic surgical instrument comprising:

mounting the robotic surgical instrument to a robotic surgical arm;

reading a memory in the robotic surgical tool to determine a tool type and any control system adjustments;

adjusting a control system to drive a first end effector to a torque in a range between an upper torque limit and a lower torque limit; and

driving the first end effector to the torque in the range.

19. The method of claim 18, further comprising:

prior to driving the first end effector,

adjusting the control system to drive a first end effector and a second end effector to a torque in a range between an upper torque limit and a lower torque limit; and

driving the first end effector and the second end effector to the torque in the range.

20. The method of claim 18, wherein

the torque is a desired joint torque at the first end effector.

21. The method of claim 19, wherein

the torque is a desired joint torque at the pivot pin of the first end effector and the second end effector.

22. The method of claim 18, wherein

driving the first end effector includes driving a first drive pulley to the torque in the range the torque is a desired joint torque at the first end effector.

23. The method of claim 19, wherein

driving the first end effector and the second end effector includes driving a first drive pulley and a second drive pulley to the torque in the range.

24. A method for a robotic surgical system comprising:

calibrating a robotic surgical instrument coupled to a robotic surgical arm prior to a robotic surgical procedure to determine a bump point between a first end effector and a second end effector;

first squeezing grips of a touch sensitive handle to close the first end effector and the second end effector around tissue;

second squeezing the grips of the touch sensitive handle to apply additional torque to the first end effector and the second end effector to apply a tip force to the tissue; and

applying a maximum torque to the first end effector and the second end effector to apply a maximum tip force to the tissue regardless of cable stretch in the robotic surgical instrument.

25. The method of claim 24, further comprising:

after applying maximum torque, supplying electrical energy to the first end effector and the second end effector to cauterize the tissue.

26. The method of claim 24, further comprising:

after applying maximum torque,

supplying electrical energy to the first end effector and the second end effector to seal the tissue closed.

27. The method of claim 24, further comprising:

determining if the grips have been released to reduce the torque at the first end effector and the second end effector,

if so, then reducing the torque to the first end effector and the second end effector, and

if not, then repeating the applying of the maximum torque.