APPARATUS AND METHOD FOR PROVIDING AN ADJUSTABLE POSITIVE STOP IN SPACE

• US 20080161829A1
• Filed: 12/21/2007
• Published: 07/03/2008
• Est. Priority Date: 12/27/2006
• Status: Active Grant

• Current Assignee: MAKO Surgical Corporation (Stryker Corporation)
• Original Assignee: MAKO Surgical Corporation (Stryker Corporation)
• Inventors: Kang, Hyosig
• Granted Patent: US 9,399,298 B2
• Time in Patent Office: Days
• US Class Current: 606/130
• CPC Class Codes: A61B 2034/102 Modelling of surgical devices, implants or prosthesis
• CPC Class Codes: A61B 2034/2055 Optical tracking systems
• CPC Class Codes: A61B 2034/2065 Tracking using image or pattern recognition
• CPC Class Codes: A61B 2034/304 including a freely orientable platform, e.g. so called 'Stewart platforms'
• CPC Class Codes: A61B 2090/034 abutting on parts of the device itself
• CPC Class Codes: A61B 2090/3945 Active visible markers, e.g. light emitting diodes
• CPC Class Codes: A61B 2090/3983 Reference marker arrangements for use with image guided surgery
• 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 34/70 Manipulators specially adapted for use in surgery
• CPC Class Codes: A61B 90/03 Automatic limiting or abutting means, e.g. for safety
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: B25J 17/0266 comprising more than two actuating or connecting rods
• CPC Class Codes: B25J 9/0042 with kinematics chains of the type prismatic-universal-universal
• CPC Class Codes: B25J 9/101 using limit-switches, -stops
• CPC Class Codes: G05B 2219/36432 By putting some constraints on some DOF, move within limited volumes, areas, planes, limits motion in x, y or z planes, virtual reality constraints
• CPC Class Codes: G05B 2219/39432 Direct robot control, click on mouse on variety of display command buttons
• CPC Class Codes: G05B 2219/45118 Endoscopic, laparoscopic manipulator
• CPC Class Codes: G05B 2219/45123 Electrogoniometer, neuronavigator, medical robot used by surgeon to operate
• CPC Class Codes: G05G 2009/04766 : providing feel, e.g. indexing means, means to create counterforce
• CPC Class Codes: G05G 5/03 : Means for enhancing the operator's awareness of arrival of the controlling member at a command or datum position; Providing feel, e.g. means for creating a counterforce arrangements for indicating the position of the controlling member G05G1/015
• CPC Class Codes: G05G 9/047 : the controlling member being movable by hand about orthogonal axes, e.g. joysticks for switches H01H25/04

Abstract

A method and apparatus for constraining motion of an end-effector in space. In one embodiment, the apparatus comprises a mechanical positioner and first and second stops. The first and second stops are controllable by a drive mechanism to constrain movement of the mechanical positioner and thereby to constrain the ability of a user to manipulate an end-effector outside a predetermined range of motion. The first and second stops are further controllable by the drive mechanism to permit movement of the end-effector within the predetermined range of motion.

Claims

1. An apparatus comprising:

a mechanical positioner for an end-effector; and

first and second stops controllable by a drive mechanism to constrain movement of the mechanical positioner and thereby to constrain the ability of a user to manipulate the end-effector outside a predetermined range of motion, and wherein the first and second stops are controllable by the drive mechanism to permit movement of the end-effector within the predetermined range of motion.

2. The apparatus of claim 1, wherein the drive mechanism is controllable to adjust at least one of the first stop and the second stop in response to movement of the mechanical positioner.

3. The apparatus of claim 1, wherein the drive mechanism is controllable to adjust at least one of the first stop and the second stop in response to movement of a workpiece.

4. The apparatus of claim 1, wherein the drive mechanism is controllable to adjust at least one of the first stop and the second stop to adjust at least a portion of the predetermined range of motion.

5. The apparatus of claim 1, wherein the first stop is moveable by a first actuator and the second stop is moveable by a second actuator.

6. The apparatus of claim 1, further comprising:

a proximal link;

a distal link; and

a joint assembly for controlling the relative position of the proximal and distal links, wherein the joint assembly comprises

an actuated linkage joint, and

a passive linkage joint; and

wherein the actuated linkage joint and the passive linkage joint in combination include the first and second stops and the mechanical positioner;

wherein, within the predetermined range of motion, the passive linkage joint moves freely to permit free movement of the end-effector; and

wherein, outside the predetermined range of motion, the passive linkage joint is constrained from moving by at least one of the first and second stops.

7. The apparatus of claim 6, wherein the joint assembly forms a prismatic joint assembly which permits a relative linear motion between the actuated linkage joint and the passive linkage joint.

8. The apparatus of claim 6, wherein the joint assembly forms a revolute joint assembly which permits a relative rotational motion between the actuated linkage joint and the passive linkage joint.

9. The apparatus of claim 1, wherein the distance between the first and second stops is adjustable.

10. A method for constraining movement of an end-effector in space, the method comprising:

permitting a linkage joint to move freely when the end-effector is positioned a distance greater than a first predetermined value from a predetermined location in space;

permitting the linkage joint to move freely within a predetermined range of motion defined by first and second stops when the end-effector is positioned a distance less than or equal to the first predetermined value and greater than a second predetermined value from the predetermined location in space; and

constraining the linkage joint from moving in a specific direction by one of the first and second stops when the end-effector is positioned a distance approximately equal to or less than the second predetermined value from the predetermined location in space, the constraining of the linkage joint constraining the movement of the end-effector in space.

11. The method of claim 10, further comprising adjusting at least one of the first and second stops in response to workpiece movement.

12. The method of claim 10, further comprising setting the location of at least one of the first and second stops in space.

13. The method of claim 10, wherein the linkage joint includes a mechanical positioner, and wherein the method further comprises tracking movement of the mechanical positioner and positioning at least one of the first and second stops in response to the movement of the mechanical positioner.

14. The method of claim 13,

wherein the positioning of the first and second stops tracks with the mechanical positioner when a haptic interaction point is positioned a distance greater than the first predetermined value from the predetermined location in space;

and

wherein the first and second stops remain stationary when the haptic interaction point is positioned a distance less than or equal to the first predetermined value from the predetermined location in space.

15. The method of claim 10, further comprising:

determining a pose of a workpiece;

determining a pose of the end-effector;

defining a relationship between the pose of the workpiece and at least one of a position, an orientation, a velocity and an acceleration of the end-effector;

associating the pose of the workpiece, the pose of the end-effector, and the relationship; and

updating the association in response to at least one motion of the workpiece and a motion of the end-effector without interrupting operation of the end-effector during use.

16. A robot comprising:

an end-effector;

a base; and

a robot arm having a positive stop apparatus comprising

a proximal link,

a distal link, and

a joint assembly for controlling the relative position of the two links, wherein the joint assembly comprises

an actuated linkage joint including a pair of stops; and

a passive linkage joint including a mechanical positioner located between the stops.

17. The robot of claim 16, wherein the base and end-effector are connected by a chain of joint and link assemblies.

18. The robot of claim 16, further comprising a drive mechanism coupled to the joint assembly, the drive mechanism controlling the pair of stops to constrain movement of the mechanical positioner and thereby to constrain the ability of a user to manipulate the end-effector outside a predetermined range of motion, and the drive mechanism moving the pair of stops to permit movement of the end-effector within the predetermined range of motion.

19. The robot of claim 16,

wherein the passive linkage joint moves freely when the end-effector is positioned a distance greater than a first predetermined value from a predetermined location in space,

wherein the passive linkage joint moves freely within a distance defined by the pair of stops when the end-effector is positioned a distance less than or equal to the first predetermined value and greater than a second predetermined value from the predetermined location in space, and

wherein the passive linkage joint is constrained from moving in a specific direction by one of the pair of stops when the end-effector is positioned a distance approximately equal to or less than the second predetermined value from the predetermined location in space.

20. The robot of claim 16, further comprising a drive mechanism configured to adjust at least one of the first or second stops in response to movement of a workpiece.

21. The robot of claim 16, further comprising a computing system programmed to:

determine a pose of a workpiece;

determine a pose of the end-effector;

define a relationship between the pose of the workpiece and at least one of a position, an orientation, a velocity and an acceleration of the end-effector;

associate the pose of the workpiece, the pose of the end-effector, and the relationship; and

update the association in response to at least one of a motion of the workpiece and a motion of the end-effector without interrupting operation of the end-effector during use.

22. An apparatus comprising:

a mechanical positioner for an end-effector; and

first and second stops controllable by a drive mechanism to constrain movement of the mechanical positioner and thereby to constrain the ability of a user to manipulate the end-effector into a forbidden region of a workspace, and wherein the first and second stops are controllable by the drive mechanism to permit movement of the end-effector within a desired region of the workspace.