Surgical Manipulator Capable of Controlling a Surgical Instrument in Multiple Modes

• US 20140039681A1
• Filed: 08/02/2013
• Published: 02/06/2014
• Est. Priority Date: 08/03/2012
• Status: Active Grant

• Current Assignee: Stryker Corporation
• Original Assignee: Stryker Corporation
• Inventors: Bowling, David Gene, Stuart, John Michael, Culp, Jerry A., Malackowski, Donald W., Moctezuma de la Barrera, Jose Luis, Roessler, Patrick, Beer, Joel N., Ketchel, John
• Granted Patent: US 9,119,655 B2
• Time in Patent Office: Days
• US Class Current: 700/261
• CPC Class Codes: A61B 17/16 Bone cutting, breaking or removal means other than saws, e.g. Osteoclasts; Drills or chisels for bones; Trepans arthroscopic bone cutters A61B17/320016; dental implant drills potentially for other surgical use A61C8/0089; bone grinders A61F2/4644, A22C17/06; A61B17/1662 takes precedence over all other subgroups except A61B17/17
• CPC Class Codes: A61B 2017/2908 Multiple segments connected by articulations
• CPC Class Codes: A61B 2034/104 Modelling the effect of the tool, e.g. the effect of an implanted prosthesis or for predicting the effect of ablation or burring
• CPC Class Codes: A61B 2034/107 Visualisation of planned trajectories or target regions
• CPC Class Codes: A61B 2034/2046 Tracking techniques
• CPC Class Codes: A61B 2034/2055 Optical tracking systems
• CPC Class Codes: A61B 2034/2059 Mechanical position encoders
• CPC Class Codes: A61B 2090/066 for measuring torque
• CPC Class Codes: A61B 34/10 Computer-aided planning, simulation or modelling of surgical operations
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 34/30 Surgical robots
• CPC Class Codes: A61B 34/32 operating autonomously
• CPC Class Codes: A61B 34/37 Master-slave robots A61B34/35 takes precedence
• CPC Class Codes: A61B 34/70 Manipulators specially adapted for use in surgery
• 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: B25J 13/00 Controls for manipulators programme controls B25J9/16; control in general G05
• CPC Class Codes: B25J 9/161 Hardware, e.g. neural networks, fuzzy logic, interfaces, processor
• CPC Class Codes: B25J 9/1633 compliant, force, torque control, e.g. combined with position control
• CPC Class Codes: Y10S 901/09 Closed loop, sensor feedback controls arm movement

Abstract

A surgical manipulator for manipulating a surgical instrument and an energy applicator extending from the surgical instrument. The surgical manipulator further includes at least one controller configured to determine a commanded pose to which the energy applicator is advanced, wherein the commanded pose is determined based on a summation of a plurality of force and torque signals.

Claims

1. A surgical manipulator for manipulating a surgical instrument and an energy applicator extending from the surgical instrument, said surgical manipulator comprising:

at least one controller configured to determine a commanded pose to which the energy applicator is advanced, wherein said commanded pose is determined based on a summation of a plurality of force and torque signals.

2. The surgical manipulator of claim 1, wherein said at least one controller is further configured to determine a commanded velocity at which the energy applicator is advanced, wherein said commanded velocity is determined based on said summation of said plurality of force and torque signals.

3. The surgical manipulator of claim 1, wherein said at least one controller is configured to control the operation of said surgical manipulator in a manual mode or a semi-autonomous mode.

4. The surgical manipulator of claim 3, wherein the operation of said surgical manipulator in manual mode or semi-autonomous mode is controlled by selectively adjusting said plurality of force and torque signals.

5. The surgical manipulator of claim 1, further including at least one arm connected at one end to said surgical instrument, said at least one arm having a plurality of links, wherein a connection between two links forms a joint and wherein an angle between two links forms a joint angle.

6. The surgical manipulator of claim 5, wherein said at least one controller includes a plurality of modules, and wherein at least one of said plurality of modules is a behavior control module configured to determine said commanded pose, and wherein at least another of said plurality of modules is a motion control module configured to determine joint angles that position the energy applicator according to said commanded pose.

7. The surgical manipulator of claim 6, wherein said behavior control module is configured to model the surgical instrument and the energy applicator as a virtual rigid body having virtual mass and virtual inertia.

8. The surgical manipulator of claim 7, wherein said behavior control module is configured to selectively apply said plurality of force and torque signals to said virtual rigid body to emulate orientation and movement of the energy applicator.

9. The surgical manipulator of claim 7, wherein said behavior control module is further configured to determine a total force and a total torque, wherein said total force and total torque are applied to a center of gravity of said virtual rigid body.

10. The surgical manipulator of claim 9, wherein said behavior control module includes a total force summer module configured to calculate said total force and said total torque based on said plurality of force and torque signals.

11. The surgical manipulator of claim 9, wherein said total force and said total torque are a sum of an instrument force vector, an orientation force vector, and an environmental force.

12. The surgical manipulator of claim 11, wherein said instrument force vector is a vector having three distinct forces and three distinct torques, said instrument force vector being selectively applied to said virtual rigid body to emulate advancement the energy applicator at a particular velocity, and wherein said orientation force vector is a force and torque vector selectively applied to said virtual rigid body to emulate repositioning of an axis of said instrument towards a centering point, and wherein said environmental force is a weighted sum.

13. The surgical manipulator of claim 12, wherein said behavior control module further includes a tool path force calculator module configured to determine said instrument force vector and said orientation force vector.

14. The surgical manipulator of claim 12, wherein said behavior control module further includes an environmental force summer configured to determine said environmental force.

15. The surgical manipulator of claim 14, wherein said environmental force summer is configured to receive a plurality of force inputs that include one or more of:

a joint limit force, an interference limit force, a workspace boundary force, an external force and a damping force.

16. The surgical manipulator of claim 15, wherein said environmental force is determined by summing said plurality of force inputs.

17. The surgical manipulator of claim 16, wherein said environmental force summer is configured to selectively balance a relative contribution of each force input by applying coefficients to each of said plurality of force inputs.

18. The surgical manipulator of claim 17, wherein said coefficients vary as a function of a transition between a manual mode of operation and a semi-autonomous mode of operation such that said coefficients are increased or decreased over a time interval following said transition.

19. A surgical manipulator for manipulating a surgical instrument and an energy applicator extending from said surgical instrument, said surgical manipulator comprising:

at least one arm connected at one end to said surgical instrument, said at least one arm having a plurality of links, wherein an angle between two links forms a joint angle;

at least one controller configured to;

model the surgical instrument and the energy applicator as a virtual rigid body;

determine a commanded pose of the energy applicator based on a summation of a plurality of force and torque signals, wherein said plurality of force and torque signals are selectively applied to said virtual rigid body to emulate orientation and movement of the energy applicator; and

determine commanded joint angles that position the energy applicator according to said commanded pose.

20. The surgical manipulator of claim 19, wherein said at least one controller is configured to control the operation of said surgical manipulator in a manual mode or a semi-autonomous mode.

21. The surgical manipulator of claim 20, wherein the operation of said surgical manipulator in manual mode or semi-autonomous mode is controlled by selectively adjusting said plurality of force and torque signals.

22. The surgical manipulator of claim 20, wherein in manual mode, said plurality of force and torque signals include forces and torques applied to the surgical instrument by a practitioner, wherein said forces and torques applied by the practitioner indicate the practitioner'"'"'s desired positioning of the surgical instrument, and wherein said at least one controller emulates the practitioner'"'"'s desired positioning of the surgical instrument by positioning the surgical instrument according to said commanded pose.

23. The surgical manipulator of claim 20, wherein in semi-autonomous mode, said plurality of force and torque signals include forces and torques directed to advancing and maintaining an orientation of the surgical instrument along a predefined path.

24. The surgical manipulator of claim 19, wherein said at least one controller is configured to selectively balance a relative contribution of each of said summed plurality of forces by applying coefficients to each of said plurality of forces.

25. A method for controlling a surgical instrument of a surgical manipulator, wherein the surgical manipulator includes at least one arm connected at one end to said surgical instrument, and wherein the at least one arm includes a plurality of links, and wherein an angle between two links forms a joint angle, and wherein an energy applicator extends from the surgical instrument, said method comprising the steps of:

modeling the surgical instrument and the energy applicator as a virtual rigid body;

determining a commanded pose for the energy applicator based on a summation of a plurality of force and torque signals, wherein said plurality of force and torque signals are selectively applied to said virtual rigid body to emulate orientation and movement of the energy applicator; and

determining commanded joint angles that position the energy applicator according to said commanded pose.

26. The method of claim 25, further including determining a commanded velocity at which the energy applicator is advanced, wherein said commanded velocity is determined based on a summation of said plurality of force and torque signals.

27. The method of claim 25, further including controlling the operation of said surgical manipulator in a manual mode or a semi-autonomous mode.

28. The method of claim 27, further including controlling the operation of said surgical manipulator in a manual mode or a semi-autonomous mode by selectively adjusting said plurality of force and torque signals.

29. The method of claim 25, further including computing a total force and a total torque, wherein said total force and total torque are applied to a center of gravity of said virtual rigid body.

30. The method of claim 29, wherein said total force and said total torque are a sum of an instrument force vector, an orientation force vector, and an environmental force.

31. The method of claim 30, wherein said instrument force vector is a vector having three distinct forces and three distinct torques, said instrument force vector being selectively applied to said virtual rigid body to emulate advancement the energy applicator at a particular velocity, and wherein said orientation force vector is a force and torque vector selectively applied to said virtual rigid body to emulate repositioning of an axis of the instrument towards a centering point, and wherein said environmental force is a weighted sum.

32. The method of claim 30, wherein said environmental force includes a plurality of force inputs that include one or more of:

a joint limit force, an interference limit force, a workspace boundary force, an external force and a damping force.

33. The method of claim 32, wherein determining said environmental force includes summing said plurality of force inputs.

34. The method of claim 33, further including selectively balancing a relative contribution of each force input by applying coefficients to each of said plurality of force inputs.

35. The surgical manipulator of claim 34, wherein said coefficients vary as a function of a transition between a manual mode of operation and a semi-autonomous mode of operation such that said coefficients are increased or decreased over a time interval following said transition.

36. A surgical system for removing a volume of material from a patient'"'"'s anatomy:

a surgical manipulator including at least one controller;

a surgical instrument manipulated by said surgical manipulator; and

an energy applicator extending from said surgical instrument to be applied to the volume of material to remove the volume of material;

said at least one controller configured to control operation of said surgical manipulator in a manual mode or a semi-autonomous mode, said at least one controller including a material logger module configured to collect data relating to locations at which said energy applicator has been applied to the volume of material in said manual mode to guide movement of said energy applicator in said semi-autonomous mode.

37. A surgical manipulator for manipulating a surgical instrument and an energy applicator extending from the surgical instrument, the surgical manipulator comprising:

at least one controller configured to operate said surgical manipulator in a manual mode or a semi-autonomous mode, said at least one controller including a feed rate calculator configured to calculate an instrument feed rate.

38. The surgical manipulator of claim 37, wherein said instrument feed rate is a velocity at which a distal end of the energy applicator advances along a path segment.

39. The surgical manipulator of claim 38, wherein said instrument feed rate is calculated by adjusting a defined feed rate.

40. The surgical manipulator of claim 39, wherein said defined feed rate is based on one or more of:

a shape of a space for which the energy applicator is applied, a type of energy applicator, patient health, nature of tissue to which the energy applicator is applied and a geometry of said path segment.

41. The surgical manipulator of claim 40, wherein adjusting said defined feed rate includes multiplying said defined feed rate by a plurality of coefficients.

42. The surgical manipulator of claim 41, wherein each of said plurality of coefficients varies as a function of a variable that is applied to said feed rate calculator.

43. The surgical manipulator of claim 42, wherein said variables includes one or more of:

a practitioner adjustment of said instrument feed rate, forces and torques to which the energy applicator is exposed, curvature of said path segment, an amount of power the surgical instrument applies through the energy applicator to a patient, temperature of a tissue to which the energy applicator is applied and a computed force that is applied to a virtual rigid body.