Staged force feedback transitioning between control states

Abstract

A surgical system is provided comprising: an input device; and a controller for receiving control inputs from the input device and for providing haptic feedback at the input device, the controller configured to apply a staged transition from a first haptic feedback profile at the input device to a second haptic feedback profile at the input device.

Claims

1. A surgical system comprising: an input device; and a controller coupled to receive control inputs from the input device and to provide haptic feedback at the input device; wherein a first non-zero haptic force feedback profile is associated with a first control state of the surgical system; wherein a second non-zero haptic force feedback profile is associated with a second control state of the surgical system; wherein the controller is configured to apply a staged transition of the haptic feedback at the input device from the first non-zero haptic force feedback profile to the second non-zero haptic force feedback profile in response to the surgical system transitioning from the first control state to the second control state; and wherein the staged transition includes one or more intermediate direction vectors produced based on summing a scaled version of a first force vector of the first non-zero haptic force feedback profile and a scaled version of a second force vector of the second non-zero haptic force feedback profile.

2. The surgical system of claim 1, wherein: the staged transition includes a curvilinear scaling.

3. The surgical system of claim 2, wherein: the curvilinear scaling is a curvilinear multi-directional scaling.

4. The surgical system of claim 1, wherein: the staged transition includes at least one discontinuity.

5. The surgical system of claim 1, wherein: the staged transition includes a zero force state.

6. The surgical system of claim 1, wherein: the staged transition includes a force-angle change.

7. The surgical system of claim 6, wherein: the staged transition includes a force-magnitude change.

8. The surgical system of claim 1, wherein: the surgical system further includes an instrument; and the first control state is an instrument control state in which the control inputs from the input device control the instrument.

9. The surgical system of claim 1, wherein: the staged transition includes maintaining the first non-zero haptic force feedback profile at the input device for a predetermined interval.

10. The surgical system of claim 1, wherein: the controller is further configured to overlay one or more haptic effects onto the staged transition; and the one or more haptic effects are associated with the second control state.

11. The surgical system of claim 10, wherein: the one or more haptic effects are overlayed onto the first non-zero haptic force feedback profile.

12. The surgical system of claim 11, wherein: the controller is further configured to restore the first non-zero haptic force feedback profile at the input device in response to the surgical system transitioning from the second control state back to the first control state.

Description

DRAWINGS

(1) Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

(2) FIGS. 1A-1B show methods of providing intuitive haptic feedback to a user of a surgical system during control state changes, in accordance with various embodiments of the invention.

(3) FIG. 2A shows an exemplary haptic force vector transition during a control state change, in accordance with various embodiments of the invention.

(4) FIG. 2B shows exemplary haptic force feedback transition profiles in accordance with various embodiments of the invention.

(5) FIGS. 3A-3C show an exemplary surgical system providing a haptic force feedback transition in response to a change in control state, in accordance with various embodiments of the invention.

DETAILED DESCRIPTION

(6) In the following detailed description of the aspects of the invention, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, it will be obvious to one skilled in the art that the embodiments of this disclosure may be practiced without these specific details. In other instances well known methods, procedures, components, and circuits have not been described in detail so as not to unnecessarily obscure aspects of the embodiments of the invention. And, to avoid needless descriptive repetition, one or more components or actions described in accordance with one illustrative embodiment can be used or omitted as applicable from other illustrative embodiments.

(7) By providing a staged transition between force feedback profiles when the control state of a surgical system changes, an intuitive haptic experience can be maintained for the user of the surgical system.

(8) FIG. 1A shows an exemplary method for providing such a staged haptic transition. In a PROVIDE HAPTIC FEEDBACK step 110, a surgical system that allows a user (e.g., surgeon) to control a surgical instrument (and/or other elements of the surgical system, such as a robotic arm, set up structure, or positioning element such as a boom or cart) via an input device(s) (e.g., lever(s), gripper(s), joystick(s), and/or any other structure capable of receiving user input) and then provides force feedback to that input device based on a desired haptic feedback profile (a set of one or more haptic feedback effects that at least partially reproduce or represent the physical experience of a real or virtual/modeled interaction). The haptic feedback profile can be based on any haptic model input, such as sensed forces at the instrument (e.g., tissue or other instrument interactions) or robotic arm (e.g., arm collisions with structures or staff), user guidance (e.g., haptic detents, fences, or other profiles to provide guidance for the user to move the input device(s) along a desired path or trajectory), and user interface (UI) elements (e.g., presenting a virtual handle or steering wheel to the user). The transformation applied to the desired haptic feedback profile to generate the haptic feedback at the input device can be anything from direct replication of the haptic feedback profile, to scaling of the haptic feedback profile, to applying a non-linear modification of the haptic feedback profile, or any other transformation (e.g., force scaling that varies depending on one or more other factors such as instrument state/speed, viewing magnification, etc.). The haptic feedback in step 110 may also include forces that are computed based on additional sensors of the surgical system such as position sensors, buttons, or contact sensors.

(9) Then in a CHANGE CONTROL STATE step 120, a control state change in the surgical system occurs (typically in response to user command/action, but in other examples in response to external commands such as system timer or warning, or third-party action/command), such that inputs at the input device are no longer providing the same effect at the surgical instrument. For example, in a surgical system that includes both a surgical instrument and a camera (e.g., endoscope), there can be instances where the control state changes from one in which the input device is controlling the surgical instrument, to a “camera control mode” where the input device is controlling the viewpoint of the camera/field of view of the surgical site. If the input device is providing haptic feedback to the user when such a control state change occurs, then immediately removing the haptic feedback in response to the change would result in an abrupt loss of force feedback at the input device, which could be disconcerting and/or disorienting to the user.

(10) Therefore, in an APPLY STAGED HAPTIC FEEDBACK TRANSITION step 130, a staged transition is performed from the original haptic feedback profile to the desired haptic feedback profile for the new control state. In other words, the transition from the original haptic feedback profile to the desired haptic feedback profile includes at least one intermediate stage that reduces the sudden change in haptic feedback that would occur from an immediate switch between the old and new haptic profiles corresponding to the switch between control states.

(11) Often, this transition from the original haptic feedback profile to the desired (new) haptic feedback profile will involve an adjustment to the force feedback vector expressed at the input device. FIG. 2A shows an exemplary haptic force feedback vector transition from an initial force F.sub.A to a new force F.sub.B. Force F.sub.A can be greater than or less than force F.sub.B (or in some embodiments equivalent, where the transition is one of direction only). The staged transition from force F.sub.A to a new force F.sub.B can take any path, including linear or curvilinear transitions, and can include discontinuities (e.g., steps) as part of the transition. For example, FIG. 2B shows several exemplary staged transitions between haptic feedback profiles that could occur in response to step 120, including a straight linear scaling (#1), a monotonic scaling (#2), a sawtooth bidirectional scaling (#3), and a curvilinear multi-directional scaling (#4). In some instances, the transition may move the force magnitude through a zero force state (e.g., #3 and #4). In various other embodiments, the transition from force F.sub.A to force F.sub.B could use several algorithms, including summing scaled versions of forces F.sub.A and F.sub.B to create intermediate direction vectors or remaining aligned with force F.sub.A for a period of time and then with force F.sub.B.

(12) Note that in some embodiments, a “phantom” haptic feedback can be maintained when changing between a control state having haptic feedback and a control state that normally would not generate haptic feedback. FIG. 1B shows an exemplary method for providing this type of stable transition.

(13) As described above with respect to FIG. 1A, in a PROVIDE HAPTIC FEEDBACK step 110, the surgical system is in a control state that provides force feedback to the input device based on haptic model input, such as sensed forces at the instrument and/or other system structure, or haptic feedback profiles based on virtual or synthetic interactive elements (e.g., user interface elements, virtual fences, and/or virtual control features, among others). Also as above, the haptic feedback in step 110 may also include forces that are computed based on additional sensors of the surgical system such as position sensors, buttons, or contact sensors. And in a CHANGE CONTROL STATE step 120, the control state of the surgical system changes to a control state for which haptic feedback is not associated (or is different than the original haptic feedback profile), such as a system settings mode, an arm change mode (i.e., switching control to a different instrument on the surgical system), or an exit following mode (i.e., simply disabling the control link between the input device and the surgical instrument), among others.

(14) Then, in a MAINTAIN HAPTIC FEEDBACK step 125, the haptic feedback profile is left unchanged even as the control state of the system changes. Such haptic feedback consistency can sometimes provide a more intuitive experience for the user, compared to changing or eliminating feedback altogether. For example, changing from an instrument control state (having haptic feedback) to a control state in which the input device is used to change system parameters (e.g., selecting menu options) and therefore does not have any logical haptic feedback relationship to the surgical instrument forces, it can be beneficial to simply maintain the feedback profile from the instrument control state even during the system settings control state, so that when the control state changes back to the instrument control state, the user is not surprised by a sudden appearance of force feedback at the input device. Thus, even though the haptic feedback profile in the new state is technically inconsistent with the control actions performed at the input device for the new state, that haptic inconsistency can actually provide a more consistent user experience.

(15) Note that in some embodiments, step 125 can include overlaying or adding additional haptic feedback associated with the new control state to the original haptic feedback profile. For in the system settings example described above, certain haptic feedback effects could be associated with the system settings control state, such as haptic “clicks” or “bumps” when settings are changed or selected. In some embodiments, such haptic effects could be provided along with the original force feedback from the previous control state.

(16) Note further that in some embodiments, the haptic feedback maintenance of step 125 can be followed by an APPLY STAGED HAPTIC FEEDBACK TRANSITION step 130, as described above with respect to FIG. 1A. In such case, the haptic feedback profile would be initially unchanged after the control state change of step 120, but would eventually undergo a staged transition to a new haptic feedback profile.

(17) FIG. 3A shows a block diagram of a surgical system 300 incorporating haptic feedback and means for providing an intuitive haptic experience for the user as described above with respect to FIGS. 1A and/or 1B. Surgical system 300 includes an instrument 310 for performing a surgical task (e.g., forceps, cutter, retractor, vessel sealer, needle driver, catheter, etc.), an input device 330 (e.g., a lever(s), gripper(s), joystick(s), or any other structure capable of receiving user input) for receiving inputs from a user (e.g., surgeon), and a controller 320 for receiving input instructions from input device 330, controlling the actions of instrument 310 accordingly via a manipulation structure 313, and providing instructions to a haptic feedback actuator 340 to provide haptic feedback to input device 330 according to a desired haptic feedback profile. In various embodiments, manipulation structure 313 can include any number of systems and structures for maneuvering, positioning, actuating, or otherwise controlling the behavior of instrument 310, including a robotic arm(s)/manipulator(s), set up structure(s), and/or positioning element(s) such as a boom(s) or cart(s), among others. Controller 320 can include any combination of hardware, software, firmware, and other modalities for generating, managing, controlling, and effecting the actions described herein. In various embodiments, controller 320 can be integrated with instrument 310, input device 330, and/or discrete control hardware (e.g., a standalone processing unit or computing platform).

(18) For exemplary purposes, FIG. 3A shows surgical system 300 in a control state A, in which input device 330 is controlling instrument 310. As depicted in FIG. 3A, the surgeon has used input device 330 to grasp and retract a portion of tissue 390 with an end effector 311 on shaft 312 of instrument 310. This results in a downward force Fs at end effector 311, and in response controller 320 delivers a haptic feedback force F.sub.A to input device 330 (e.g., as described with respect to step 110 above). In this manner, the surgeon would “feel” the resistance being provided by tissue 390 as it is being retracted.

(19) Note that this description of control state A is for exemplary purposes only, as this initial control state A could be any state of surgical system 300. For example, while the haptic feedback profile force F.sub.A is described as being derived from a force FS sensed at end effector 311 of instrument 310 for exemplary purposes, in various other embodiments, force FS could be sensed at any location for which corresponding haptic feedback at input device 330 would be beneficial, such as interactions at shaft 312 or any other element of manipulation structure 313 (e.g., arm pressure against structures or staff).

(20) In various other embodiments, force FS can be defined according to non-physical parameters, such as the synthetic interactive elements described above. For example, in some embodiments, surgical system 300 can include an optional display 350 (e.g., a monitor(s), a head-in viewer(s), projections, video glasses/helmet(s), and/or any other graphical presentation element). In various embodiments, display 350 can present a virtual or synthetic element 361 that can be interacted with via input device 330. In some embodiments, synthetic element 361 can be used as a supplemental interface for interacting with a physical component of surgical system 300. For example, as shown in FIG. 3A, synthetic element 361 can be a virtual handle or knob that can be “grasped” and dragged around using input device 330 to reposition instrument 310 at the surgical site. In other embodiments, synthetic element 361 can provide a purely virtual interaction element, such as a dial, toggle, lever, or any other structure for controlling surgical system 300. In any case, by generating a haptic feedback profile based on model forces FS1 associated with interacting with synthetic element 361 (e.g., radially outward resistive force produced with grasping a round knob), controller 320 can then attempt to provide an appropriate haptic feedback profile force F.sub.A at input device 330.

(21) In various other embodiments, surgical system 300 may provide guidance to the user with respect to movement of instrument 310 and/or input device 330. For example, a desired motion of instrument 310 (e.g., a targeted or safe dissection path, a desired retraction movement, or any other beneficial articulation) could optionally be defined as a trajectory 362. By generating a haptic feedback profile based on model forces FS2 associated with maintaining the position of instrument 310 along trajectory 362 (e.g., inwardly directed forces produced upon deviations from trajectory 362), controller 320 can then attempt to provide an appropriate haptic feedback profile force F.sub.A at input device 330.

(22) Then, in an exemplary control state change to a new control state B depicted in FIG. 3B (e.g., as described with respect to step 120 above) shifts control by input device 330 from its existing element (e.g., original instrument 310 such as a retractor) to a new element (e.g., instrument 310(2) such as a needle driver for suturing tissue 390). The control state change results in a force Fs' at the new element (e.g., instrument 310(2)), different than the force Fs at original element (e.g., instrument 310), needing to be expressed as haptic feedback F.sub.B at input device 330. Thus, over a time (t2−t1), a staged transition from haptic force feedback F.sub.A to F.sub.B is performed, as described with respect to step 130 above. As noted previously, because of the staged transition the user at input device 330 does not experience a sudden and disconcerting jump from force feedback F.sub.A to F.sub.B that would otherwise occur if the force feedback transformation applied to the sensed force switched concurrently with the control state change. For example, the staged transition would ensure that haptic feedback representative of supporting retracted tissue would not immediately vanish, or that the sense of holding a virtual knob or handle would not immediately disappear.

(23) In other embodiments, another exemplary control state change from control state A in FIG. 3A to a new control state C depicted in FIG. 3C (e.g., as described with respect to step 125 above) shifts input device 330 control from instrument 310 (or any other control state with haptic feedback) to a system setting selection interface 321 (or any other control state with no haptic feedback (or different haptic feedback)). Here, the haptic feedback profile is maintained even as the control state is changed, and thus the feedback force at input device 330 is maintained as force F.sub.A, even though the settings selection menu is not a force-generating environment. As a result, the user is not surprised by a sudden disappearance of force feedback at the input device (or a sudden reappearance of force feedback once the selection menu is exited).

(24) As noted above, in some embodiments the retained haptic force F.sub.A be overlaid with additional haptic feedback associated with the new control state, such as haptic “clicks” or “bumps” when settings are changed or selected. As further noted above, the maintained haptic feedback can be followed by a subsequent staged transition to a new haptic feedback profile.

(25) While certain exemplary embodiments of the invention have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative of and not restrictive on the broad invention, and that the embodiments of the invention not be limited to the specific constructions and arrangements shown and described, since various other modifications may occur to those ordinarily skilled in the art.