METHOD AND SYSTEM FOR AUTOMATICALLY MAINTAINING AN OPERATOR SELECTED ROLL ORIENTATION AT A DISTAL TIP OF A ROBOTIC ENDOSCOPE

• US 20110196199A1
• Filed: 01/26/2011
• Published: 08/11/2011
• Est. Priority Date: 02/11/2010
• Status: Active Grant

• Current Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Original Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Inventors: Donhowe, Caitlin Q., Prisco, Giuseppe Maria
• Granted Patent: US 8,668,638 B2
• Time in Patent Office: Days
• US Class Current: 600/102
• CPC Class Codes: A61B 1/00147 Holding or positioning arrangements
• CPC Class Codes: A61B 1/0051 with controlled bending of insertion part
• CPC Class Codes: A61B 1/0055 Constructional details of insertion parts, e.g. vertebral elements
• CPC Class Codes: A61B 1/009 with bending or curvature detection of the insertion part
• CPC Class Codes: A61B 2034/2061 using shape-sensors, e.g. fiber shape sensors with Bragg gratings
• CPC Class Codes: A61B 5/065 Determining position of the probe employing exclusively positioning means located on or in the probe, e.g. using position sensors arranged on the probe

Abstract

In a robotic endoscope system, the orientation of a captured camera view at a distal tip of a robotic endoscope and displayed on a screen viewable by an operator of the endoscope is automatically maintained at a roll orientation associated with a setpoint so as not to disorient the operator as the endoscope is moved, flexed and its tip turned in different orientations. A processor generates a current commanded state of the tip from operator input and modifies it to maintain the setpoint roll orientation. To generate the modified current commanded state, the current commanded roll position and velocity are constrained to be a modified current commanded roll position and velocity that have been modified according to a roll angular adjustment indicated by a prior process period commanded state of the tip and the setpoint. The processor then commands the robotic endoscope to be driven to the modified commanded state.

Claims

1. A method for controlling operator commanded movement of a distal tip of a robotic endoscope while maintaining a roll orientation at the tip, the method comprising:

receiving a control input from an operator manipulatable input control device;

determining a current commanded state of the tip of the robotic endoscope from the control input, wherein the commanded state includes a current commanded roll position and velocity;

modifying the current commanded state by constraining the current commanded roll position and velocity to be a modified current commanded roll position and velocity according to a roll angular adjustment indicated by a prior process period commanded state of the tip and a setpoint indicative of the roll orientation to be maintained at the tip; and

commanding the tip of the robotic endoscope to be driven to the modified current commanded state.

2. The method according to claim 1, wherein a tip reference frame is defined at the tip of the endoscope so as to have a Z_TIP axis indicative of a depth direction of a view captured at the tip, a X_TIP axis indicative of a horizontal direction of the view, and a Y_TIP axis indicative a vertical direction of the view, the method further comprising:

receiving a reference vector indicative of the setpoint;

projecting the reference vector onto a plane containing the Y_TIP axis and the Z_TIP axis; and

determining the roll angular adjustment as an angle between the reference vector and the projected reference vector.

3. The method according to claim 1, where the current commanded roll velocity is modified by setting it to zero and the commanded roll position is modified by setting it to the prior process period commanded roll position as long as the roll angular adjustment is less than a threshold value.

4. The method according to claim 1, wherein the current commanded roll velocity is modified by setting it to a fixed value and the commanded roll position is adjusted to a value consistent with the modified current commanded roll velocity whenever the roll angular adjustment is greater than a threshold value.

5. The method according to claim 1, wherein the current commanded roll velocity is modified so as to be a function of the roll angular adjustment and the current commanded roll position is adjusted to a value consistent with the modified current commanded roll velocity whenever the roll angular adjustment is greater than a threshold value.

6. The method according to claim 1, wherein the setpoint is established so as to be orthogonal to gravity.

7. The method according to claim 1, further comprising:

receiving an indication of the setpoint from an operator manipulated input device.

8. The method according to claim 7, wherein the setpoint is established by a roll orientation at the tip at the time that the indication of the setpoint is received from the operator.

9. The method according to claim 7, further comprising:

displaying a graphical representation of the setpoint on a display screen viewable by the operator;

receiving an input from the operator manipulated input device;

adjusting an orientation of the graphical representation of the setpoint on the display screen according to the received input; and

determining the setpoint from the adjusted orientation of the graphical representation of the setpoint.

10. The method according to claim 1, wherein the commanding of the tip of the robotic endoscope to be driven to the modified current commanded state comprises:

determining a combination of states for one or more joints of a manipulator that manipulates the robotic endoscope in corresponding degrees of freedom movement and bending angles for one or more bending segments of the robotic endoscope to bend a body of the robotic endoscope so as to achieve the modified current commanded state of the tip of the robotic endoscope; and

commanding the one or more joints of the manipulator to be driven to the determined joint states and the one or more bending segments of the robotic endoscope to be driven to the determined bending angles.

11. The method according to claim 10, wherein the one or more joints of the manipulator includes a prismatic joint for moving a proximal end of the robotic endoscope forward and backward along a linear path and a rotary joint for rotating the proximal end of the robotic endoscope about the linear path.

12. The method according to claim 10, wherein the determining of the current commanded state of the tip of the robotic endoscope from the control input comprises:

determining translational and angular tip states from the control input and stored information of control inputs for one or more prior process periods.

13. The method according to claim 10, wherein the determining of the current commanded state of the tip of the robotic endoscope from the control input comprises:

transforming the control input to a desired state of the tip of the robotic endoscope relative to a fixed Cartesian reference frame.

14. The method according to claim 13, wherein the determining of the states of the one or more joints of the manipulator and bending angles for the one or more bending segments of the robotic endoscope comprises:

applying the modified current commanded state to inverse kinematics of the combined serial kinematic chain composed of the manipulator and the robotic endoscope.

15. A medical robotic system comprising:

a robotic endoscope having an elongate body including one or more bendable segments and a distal tip;

a manipulator having one or more drivable joints for manipulating the robotic endoscope in corresponding degrees of freedom movement;

an operator manipulatable input control device; and

a processor configured to receive a control input from the operator manipulatable input control device, determine a current commanded state of the tip of the robotic endoscope from the control input wherein the current commanded state includes a commanded roll position and velocity, modify the current commanded state by constraining the current commanded roll position and velocity to be a modified current commanded roll position and velocity according to a roll angular adjustment indicated by a prior process period commanded state of the tip and a setpoint indicative of the roll orientation to be maintained at the tip, and command the tip of the robotic endoscope to be driven to the modified current commanded state.

16. The medical robotic system according to claim 15, wherein a tip reference frame is defined at the tip of the endoscope so as to have a Z_TIP axis indicative of a depth direction of a view captured at the tip, a X_TIP axis indicative of a horizontal direction of the view, and a Y_TIP axis indicative a vertical direction of the view;

and wherein the processor is further configured to receive a reference vector indicative of the setpoint, project the reference vector onto a plane containing the Y_TIP axis and the Z_TIP axis, and determine the roll angular adjustment as an angle between the reference vector and the projected reference vector.

17. The medical robotic system according to claim 15, where the processor is configured to modify the current commanded roll velocity by setting it to zero and modify the current commanded roll position by setting it to the prior process period commanded roll position as long as the roll angular adjustment is less than a threshold value.

18. The medical robotic system according to claim 15, wherein the processor is configured to modify the current commanded roll velocity by setting it to a fixed value and adjust the current commanded roll position to a value consistent with the modified current commanded roll velocity whenever the roll angular adjustment is greater than a threshold value.

19. The medical robotic system according to claim 15, wherein the processor is configured to modify the current commanded roll velocity so as to be a function of the roll angular adjustment and adjust the commanded roll position to a value consistent with the modified current commanded roll velocity whenever the roll angular adjustment is greater than a threshold value.

20. The medical robotic system according to claim 15, wherein the setpoint has been established so as to be orthogonal to gravity.

21. The medical robotic system according to claim 15, wherein the processor is configured to receive an indication of the setpoint from an operator manipulated input device.

22. The medical robotic system according to claim 21, wherein the processor is configured to establish the setpoint by a roll orientation at the tip at the time that the indication of the setpoint is received from the operator.

23. The medical robotic system according to claim 21, further comprising:

a display screen; and

an operator manipulatable input device;

wherein the processor is configured to display a graphical representation of the roll setpoint on the display screen, receive an input from the operator manipulatable input device, adjust an orientation of the graphical representation of the roll setpoint on the display screen according to the received input, and determine the roll setpoint from the adjusted orientation of the graphical representation of the roll setpoint.

24. The medical robotic system according to claim 15, wherein the processor is configured to command the tip of the robotic endoscope to be driven to the modified current commanded state by determining a combination of states for the one or more joints of the manipulator and bending angles for the one or more bendable segments of the elongate body so as to achieve the modified current commanded state of the tip of the robotic endoscope;

and commanding the one or more joints of the manipulator to be driven to the determined joint states and the one or more bendable segments of the robotic endoscope to be driven to the determined bending angles.

25. The medical robotic system according to claim 24, wherein the one or more joints of the manipulator includes a prismatic joint for moving a proximal end of the robotic endoscope forward and backward along a linear path and a rotary joint for rotating the proximal end of the robotic endoscope about the linear path.

26. The medical robotic system according to claim 20, wherein the processor is configured to determine the current commanded state of the tip of the robotic endoscope from the control input by determining translational and angular tip states from the control input and stored information of control inputs for one or more prior process periods.

27. The medical robotic system according to claim 24, wherein the processor is configured to determine the commanded state of the tip of the robotic endoscope from the control input by transforming the control input to a desired state of the tip of the robotic endoscope relative to a fixed Cartesian reference frame.

28. The medical robotic system according to claim 27, wherein the processor is configured to determine the states of the one or more joints of the manipulator and the bending angles for the one or more bendable segments of the robotic endoscope by applying the modified current commanded state to inverse kinematics of the combined serial kinematic chain composed of the manipulator and the robotic endoscope.