An apparatus, computer-implemented method and computer program

Abstract

An apparatus comprising: at least one processor; and at least one memory including computer program code. The at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to: receive a recalibration command from a passive controller configured to remotely control a robotic instrument, wherein the passive controller and the robotic instrument have degrees of freedom of movement within respective control workspaces and instrument workspaces, and wherein the control workspace is mapped to the instrument workspace to allow a position of the robotic instrument to track a position of the passive controller as the passive controller is moved within the control workspace; and, in response to the recalibration command, recalibrate the mapping of the control workspace to the instrument workspace so that a current position of the passive controller corresponds to a current position of the robotic instrument.

Description

Technical Field

[0001] The present invention generally relates to remotely controlled robot systems, and more particularly to an apparatus, associated method, and computer program for recalibrating the tracking of a robot instrument to a passive controller. Background Technology

[0002] Remotely controlled robotic systems have applications in many fields, particularly where human access, safety, or both are restricted. For example, they can be used in minimally invasive surgery where access to the surgical site is limited to natural cavities and / or small incisions. Human hands are too large to access these areas, so small robots remotely controlled by the surgeon can be used instead. Remotely controlled robotic systems are also used in military applications such as bomb disposal, where robots can be operated remotely from a safe distance.

[0003] Therefore, this invention is primarily described in relation to surgical robot systems. However, this is for illustrative purposes only and does not preclude the application of the invention in other fields.

[0004] Known remotely controlled surgical robot systems include a controller and a robotic instrument, wherein a user can issue commands to the robotic instrument by manipulating the controller. Known controllers include a base, an articulated arm coupled to the base and including multiple joints (e.g., rotatable or prismatic joints), and a handle coupled to the articulated arm and movable relative to the base via joint movement. Known robotic instruments include a base, an actuated arm coupled to the base and including multiple joints, and an end effector coupled to the actuated arm and actuated relative to the base via joint movement.

[0005] Controllers and robotic instruments, particularly handles and end effectors, each possess a degree of freedom of movement within their respective control and instrumentation workspaces. Furthermore, handles and end effectors may each have six degrees of freedom of movement within their respective workspaces, including translational movement along three axes and rotational movement about three axes. Handles and end effectors can be considered as having a position within their respective workspaces that depends on translational movement, and an orientation relative to their respective workspaces that depends on rotational movement. Moreover, the position and orientation of a handle or end effector can be collectively considered as its attitude.

[0006] Users can manipulate the position and orientation of the handle within the controller workspace, and this manipulation can be tracked by measuring the movement of each joint in the actuated arm. These manipulations are translated into commands for the robotic instrument, specifically commands for the joints of the actuated arm, such that the position and orientation of the end effector in the instrument workspace moves in correspondence with the manipulation of the handle in the controller workspace.

[0007] The known controller is an active controller, meaning that when the robotic system is in use, the torque required for each joint in the rotary controller actively changes based on input from the user. For example, if the user releases the controller, the torque of each joint changes, causing the handle to remain in the last position and orientation reached by the user's manipulation. In other words, the controller freezes unless the user provides further input. By extension, robotic instruments can also freeze.

[0008] Furthermore, when the movement of a robotic device is limited by its available workspace, corresponding restrictions can be imposed on the controller, for example, by limiting the rotation of joints beyond a certain point. This prevents the controller from becoming misaligned with the robotic device.

[0009] However, actively changing the torque of each joint in a controller requires the controller to include expensive and bulky components such as servo motors. Therefore, known active controllers are costly to manufacture and lack portability. Furthermore, active changes in torque within the controller's joints may encourage users to assume unwanted and / or unnatural positions, potentially causing user frustration or errors.

[0010] The listing or discussion of previously published literature or any background information in this specification should not be construed as an admission that such literature or background is part of the current state of the art or common knowledge. One or more aspects / implementations of this disclosure may or may not solve one or more of the background problems. Summary of the Invention

[0011] According to a first aspect of the invention, an apparatus is provided, comprising: at least one processor; and at least one memory including computer program code. The at least one memory and the computer program code are configured to cause the apparatus, using the at least one processor, to: receive a recalibration command from a passive controller configured to remotely control a robotic instrument, wherein the passive controller and the robotic instrument have degrees of freedom of movement within their respective control workspaces and instrument workspaces, and wherein the control workspace is mapped to the instrument workspace to allow the position of the robotic instrument to track the position of the passive controller as the passive controller moves within the control workspace; and, in response to the recalibration command, recalibrate the mapping from the control workspace to the instrument workspace such that the current position of the passive controller corresponds to the current position of the robotic instrument.

[0012] Passive controllers are controllers that include freely movable joints, where the torque required to rotate the joints does not actively change as in active controllers. Compared to known active controllers, passive controllers offer advantages such as lower manufacturing costs, smaller size, and lighter weight because they do not require expensive, heavy, or bulky components, such as servo motors. Furthermore, the absence of active changes in joint torque prevents the user's movements from being biased towards uncomfortable or unnatural postures, which could lead to the transmission of suboptimal or unexpected commands to the associated robotic machinery.

[0013] However, because the user of the passive controller can freely manipulate it within its workspace without human constraint, the passive controller can potentially be moved to a location that causes misalignment with the associated robotic instrument. For example, the passive controller might be moved to a location within the control workspace, and due to the differences between the control workspace and the instrument's workspace, the robotic instrument cannot replicate that location within the instrument's workspace. Furthermore, for safety reasons, the speed at which the robotic instrument can move within its workspace may be limited, and the user of the passive controller might move it too quickly within the control workspace, preventing the robotic instrument from mirroring itself within the instrument's workspace.

[0014] If the position of the passive controller is misaligned with the position of the robotic instrument, the user may find it difficult to continue accurately controlling the robotic instrument because the movement of the passive controller within the control workspace may no longer be accurately mirrored by the robotic instrument in the workspace. In other words, controlling the robotic instrument may become less intuitive when the position of the passive controller is misaligned with the position of the robotic instrument.

[0015] This invention allows for the recalibration of the mapping between the control workspace and the instrument workspace, ensuring that the current position of the passive controller corresponds to the current position of the robotic instrument. Therefore, the positions of the passive controller and the robotic instrument are realigned, enabling the user to more easily and precisely control the robotic instrument.

[0016] In embodiments of the invention, the passive controller may include a clutch mechanism configured to allow the position of the passive controller within the control workspace to change without causing a corresponding change in the position of the robot instrument within the instrument workspace, and to receive a recalibration command from the passive controller when the clutch mechanism is engaged or subsequently disengaged.

[0017] In these embodiments of the invention, a user of the passive controller can engage the clutch mechanism to stop the passive controller's translational movement within the control workspace, which causes a corresponding translational movement of the robot within the instrument workspace. In other words, when the clutch mechanism is engaged, the robot will remain in its last actuated position before the clutch mechanism was engaged, even if the position of the passive controller changes during this period.

[0018] This can be advantageous when a user of a passive controller wants to move the controller to a more comfortable or easily accessible location within the control workspace, but also wants to keep the robotic instrument in the same position within the instrument workspace. The clutch mechanism can also allow the user to take a break from controlling the robotic instrument. For example, during a long surgical procedure, a surgeon may want to rest to relax the muscles used to perform very precise movements, or to pass information or instructions to other members of the surgical team.

[0019] Because the passive controller can move within the control workspace, while the robotic instrument remains stationary within the instrument workspace, it is highly likely that the passive controller will become misaligned with the robotic instrument during clutch engagement. However, when the clutch is engaged / disengaged, a recalibration of the mapping between the control and instrument workspaces will realign the passive controller position with the robotic instrument position. This means that any changes made by the user to the passive controller position while the clutch is engaged should have virtually no impact on the accuracy and intuitiveness of the user's control over the robotic instrument once the clutch is disengaged.

[0020] In embodiments of the invention, the passive controller may include an engagement mechanism configured to initiate tracking of the robot instrument position to the passive controller position, and to receive a recalibration command from the passive controller when the engagement mechanism is activated.

[0021] In these embodiments of the invention, when a user first initiates operation of the robotic device, the control workspace can be mapped to the device workspace, such that the current position of the passive controller corresponds to the starting position of the robotic device. Therefore, when the user begins to control the robotic device, the engagement mechanism ensures that the passive controller and the robotic device are aligned, allowing the user to control the passive controller precisely and intuitively.

[0022] In embodiments of the invention, the passive controller may include an unlocking mechanism configured to restart tracking from the robot instrument position to the passive controller position after a tracking interruption, and to receive a recalibration command from the passive controller when the unlocking mechanism is activated.

[0023] In these embodiments of the invention, if the operation of the robotic device is interrupted and the user wants to restart the operation, the passive controller and the robotic device can be aligned with an unlocking mechanism, similar to the engagement mechanism.

[0024] In embodiments of the present invention, the orientation of the robotic instrument can track the orientation of the passive controller, and the device can be configured to automatically control the orientation of the robotic instrument so that it aligns with the orientation of the passive controller when the engagement or unlocking mechanism is activated.

[0025] When a robot is first started operating, or when its operation is restarted after an interruption in the robot's tracking passive controller, the robot's orientation relative to the machine workspace is likely to be misaligned with the passive controller's orientation relative to the control workspace. To compensate for this, after the engagement or disengagement mechanism is activated, the device can automatically control the robot's orientation to align it with the passive controller's current orientation.

[0026] When combined with the recalibration of the mapping from the control workspace to the machine workspace, so that the passive controller position corresponds to the robot machine position, the positions and orientations of both the passive controller and the robot machine can be aligned. Therefore, whenever a user starts or restarts operation of the robot machine, they can begin from a position and orientation aligned with that of the passive controller. This ensures comfortable and intuitive control of the robot machine.

[0027] In embodiments of the present invention, the device may be configured to determine the movement trajectory of the robot instrument within the instrument workspace based on the current orientation of the passive controller, thereby achieving the automatic control.

[0028] In these embodiments of the invention, a trajectory can be determined to move the robotic device so that its orientation corresponds as closely as possible to the orientation of the passive controller. Based on the movement trajectory, commands can be issued to a motor that drives the actuation of the robotic device, thereby causing the robotic device to follow the movement trajectory.

[0029] In embodiments of the invention, the device can be configured to redetermine the movement trajectory when the current orientation of the passive controller changes.

[0030] In these embodiments of the invention, in order to align the robot's orientation with the current orientation of the passive controller, rather than with the passive controller's old and incorrect orientation, the movement trajectory is updated based on the passive controller's current orientation. Therefore, when the robot is moved automatically, there will be no orientation misalignment caused by the movement of the passive controller.

[0031] In embodiments of the invention, the robotic instrument can be configured to rearrange itself between an initial posture and one or more other postures, and the device can be configured to automatically control the arrangement of the robotic instrument so that it returns from one or more other postures to the initial posture when the homing mechanism is activated.

[0032] In these embodiments of the invention, the initial posture of the robotic instrument can be a combination of rotational positions of each joint that forms part of the robotic instrument, which are held when the robotic instrument is inactive. For example, the initial posture can correspond to a linear arrangement of the joints, which is advantageous for inserting or removing the robotic instrument from the surgical site. The initial posture can also correspond to a neutral arrangement of the joints from which the robotic instrument can be easily moved to any position and orientation within the instrument's workspace.

[0033] A return mechanism provides a means to automatically return a robotic instrument from any other posture it may have moved into during use to its initial posture. This can be useful, for example, when a surgeon has completed surgery and is preparing to withdraw the robotic instrument from the surgical site, or when a part of a surgery has been completed and the surgeon wishes to begin the next stage of the procedure with the robotic instrument in a neutral position.

[0034] In embodiments of the invention, the device may be configured to limit the movement speed of the robotic instrument to a predetermined range during alignment / arrangement.

[0035] In these embodiments of the invention, the automatic movement of the robotic device can be limited to a speed that allows the user to monitor the movement appropriately and reduce the risk of unsafe movement.

[0036] In embodiments of the invention, the device may be configured to stop the automated control of the robotic instrument upon receiving a cancellation command or once alignment / arrangement is complete.

[0037] In these embodiments of the invention, the user can monitor automated control until the robotic instrument has reached the desired orientation or posture, at which point automated control will cease and the user can resume control. If the user believes that the trajectory of the robotic instrument during automated control may be unsafe, the user can trigger a cancellation command received by the device. For example, the trajectory of the robotic instrument determined by the device may cause the robotic instrument to come too close to the patient's soft tissue. The cancellation command causes automated control to stop, allowing the user to resume control of the robotic instrument. For example, this allows the user to navigate the robotic instrument away from the observed danger, and once the robotic instrument appears to be in a safe position, the user can restart the interrupted alignment or placement process.

[0038] In embodiments of the invention, the engagement mechanism may include a proximity sensor configured to detect the presence of a user, and the device may be configured to initiate tracking of the robot's position to the passive controller's position only when the proximity sensor detects the presence of a user.

[0039] In these embodiments of the invention, the proximity sensor can be any suitable type of proximity sensor, appropriately configured to detect the presence of a user. For example, the passive controller may include a handle that a user grips when operating the passive controller. The proximity sensor may be part of the handle and may be configured to detect when the user grips the handle. The device is configured to initiate tracking of the robotic instrument to the passive controller only when the proximity sensor detects the presence of a user, which can reduce the potential for dangerous corresponding movements of the robotic instrument caused by unintentional movement of the passive controller.

[0040] In embodiments of the present invention, the device can be configured to stop the robot from tracking the position of the passive controller when the proximity sensor detects that the user is not present.

[0041] In these embodiments of the invention, the movement of the passive controller after detecting the user's absence will not be tracked by the robotic instrument. This can be particularly advantageous, for example, if the user accidentally drops the passive controller. Since the passive controller is passive rather than active, it will move due to gravity if dropped by the user. When used during surgery, the corresponding movement of the robotic instrument could potentially harm the patient. Therefore, the device is configured to stop the robotic instrument from tracking the passive controller when the user's absence is detected, which improves the safety of the robotic instrument.

[0042] In embodiments of the present invention, the passive controller may include an electronic display screen configured to display a diagram of the instrument workspace and the control workspace, and the device may be configured to control the electronic display screen such that the current position and / or orientation of the robot instrument and the passive controller are indicated within the diagram of their respective instrument workspace and control workspace.

[0043] In these embodiments of the invention, the user can monitor the current position and / or orientation of the robotic instrument and the passive controller within their respective instrument and control workspaces, as well as how the control workspace is mapped to the instrument workspace. This helps the user understand the operable degrees of freedom and movement limitations of the robotic instrument, and can inform the user when it may be beneficial to activate the unlocking or homing mechanism. For example, it can also help the user understand when the passive controller becomes misaligned with the robotic instrument and when it may be necessary to engage the clutch mechanism.

[0044] In embodiments of the present invention, the device may be configured to control an electronic display screen such that the current position and / or orientation is indicated in a two-dimensional or three-dimensional manner.

[0045] In these embodiments of the invention, a two-dimensional illustration of the current position and / or orientation may be easier for the user to understand, and this representation may be particularly useful if the robotic device is limited to movement primarily within two dimensions. Meanwhile, a three-dimensional representation of the current position and / or orientation is more informative for the user, especially when the robotic device can move freely in three-dimensional space.

[0046] The positions of the robotic instruments and passive controllers (e.g., positions in the xy-coordinate plane) can be indicated by points within a two-dimensional representation of their respective instrument and control workspace. Alternatively, orientation can be indicated by arrows radiating outward from that point in two-dimensional or three-dimensional space. Furthermore, translation sliders can be used to indicate translational positions (z) perpendicular to the xy-coordinate plane.

[0047] In embodiments of the present invention, the current position and / or orientation of the passive controller and the robotic instrument can be the last known position and / or orientation of the passive controller and the robotic instrument relative to the device, respectively.

[0048] In embodiments of the present invention, the robotic device may include an end effector, and the current position and / or orientation of the robotic device may be the current position and / or orientation of the end effector.

[0049] In embodiments of the present invention, the robotic device may be a surgical robotic device.

[0050] In embodiments of the present invention, the device may include a passive controller and / or a robotic device.

[0051] According to a second aspect of the invention, a computer-implemented method is provided, the method comprising: receiving a recalibration command from a passive controller configured to remotely control a robotic instrument, wherein the passive controller and the robotic instrument have degrees of freedom of movement in their respective control workspaces and instrument workspaces, and wherein the control workspace is mapped to the instrument workspace to allow the position of the robotic instrument to track the position of the passive controller as the passive controller moves within the control workspace; and, in response to the recalibration command, recalibrating the mapping from the control workspace to the instrument workspace such that the current position of the passive controller corresponds to the current position of the robotic instrument.

[0052] Unless explicitly stated or understood by a person skilled in the art, the steps of any method disclosed herein need not be performed in the exact order disclosed.

[0053] According to a third aspect of the invention, a computer program (which may or may not be recorded on a carrier) is provided, the program comprising computer code configured to perform the method according to a second aspect of the invention.

[0054] This disclosure includes one or more corresponding aspects, exemplary embodiments, or features, which may be individual or in various combinations, whether or not they are specifically described in such combination or individually (including claimed). Corresponding measures for performing the one or more functions discussed are also within the scope of this disclosure.

[0055] The above overview is exemplary and not restrictive. Attached Figure Description

[0056] Embodiments of the invention will now be described by way of example only, with reference to the accompanying drawings, in which:

[0057] Figure 1 This is a schematic diagram of the device according to the first aspect of the present invention in use;

[0058] Figure 2 It constitutes Figure 1 A schematic diagram of a passive controller for a portion of the device shown;

[0059] Figure 3 It constitutes Figure 1 A schematic diagram of a portion of the robotic apparatus shown.

[0060] Figure 4 This is a schematic diagram of the control workspace mapped to the instrument workspace before recalibration;

[0061] Figure 5 This is a schematic diagram of the control workspace mapped to the instrument workspace after recalibration;

[0062] Figure 6 yes Figure 1 A schematic diagram of the clutch operation that the device shown can perform;

[0063] Figure 7 yes Figure 1 A schematic diagram of the engagement operation that the device can perform;

[0064] Figure 8 yes Figure 1 A schematic diagram of the unlocking operation that the device shown can perform;

[0065] Figure 9 It is a diagram of the global solution for any function;

[0066] Figure 10 It is aimed at Figure 9A diagram illustrating a local solution of the arbitrary function shown.

[0067] Figure 11 , Figure 12 and Figure 13 It is a graphical representation of constrained and unconstrained solutions for different arbitrary functions;

[0068] Figure 14 yes Figure 1 A schematic diagram illustrating the homing operation that the device can perform; and

[0069] Figure 15 yes Figures 6 to 8 and Figure 14 The diagram shows a combination of operations. Detailed Implementation

[0070] First see Figure 1 The device according to the first aspect of the invention is generally indicated by reference numeral 2. Device 2 includes at least one processor and at least one memory including computer program code. Device 2 is shown as being used by user 4 in operating room 6 to perform surgery on patient 8. Therefore, user 4 can be a surgeon.

[0071] In this embodiment of the invention, the device 2 further includes a control station 10, which includes a pair of passive controllers 12. Figure 2 (See in more detail below), window 14 and foot pedal controller 16. The passive controller 12 can be operated by the user 4 in their respective control workspaces.

[0072] The device also includes a monitor 18 and a surgical robot 20, which includes a pair of robotic instruments 22 (one of which is shown in detail below). Figure 3 The system comprises a robot platform 24 and a robot motor 26. The robot instrument is mounted on the robot platform 24, which is arranged to position the robot instrument within the patient's body. The robot motor 26 is also mounted on the robot platform 24 and operatively coupled to the robot instrument to drive its movement within its respective instrument workspace.

[0073] Window 14 includes an electronic display screen configured to display a diagram of the instrument workspace and the control workspace. Furthermore, device 2 is configured to control the electronic display screen such that the current position and / or orientation of the robot instrument and the passive controller 12 are indicated in the diagrams of their respective instrument workspaces and control workspaces. Additionally, device 2 is also configured to control electronic display screen 18 to indicate the current position and / or orientation in a two-dimensional or three-dimensional manner.

[0074] The current position and / or orientation of the passive controller 12 and the robot instrument are respectively the last known position and / or orientation of the passive controller 12 and the robot instrument with respect to the device.

[0075] Endoscope 28 is also mounted on robotic platform 24 and inserted into patient 9. Endoscope 28 can record images of the surgical site, including the robotic instruments in use, and the recorded images can be transmitted via control station 10 to window 14 for display on an electronic display screen. The recorded images can be displayed together with illustrations of the control workspace and instrument workspace, or the workspace can be overlaid on the recorded images. Monitor 18 can display the recorded images, illustrations of the control workspace and instrument workspace, status information of device 2, or any suitable combination of these.

[0076] See now Figure 2 Each passive controller 12 includes a controller base 30, an articulated arm 32 coupled to the controller base 30 and including a plurality of controller joints 34, and a handle 36 coupled to the articulated arm 32 and including a gripper 38. Each controller joint 34 is freely rotatable, meaning that the torque required to rotate each joint cannot be actively changed as in known active controllers. Thus, the handle 36 can be freely moved by the user 4 within its respective control workspace (e.g., ...). Figure 1 (As shown). Furthermore, each passive controller 12, and in particular each handle 36, can be considered to have a position in its respective control workspace and an orientation relative to the control workspace.

[0077] From this point forward, embodiments of the invention will be described with reference to a single passive controller 12 and a corresponding robotic device. However, it will be understood that the device may include two or more passive controllers and a corresponding number of robotic devices.

[0078] See now Figure 3 Robotic device 22 is equivalent to Figure 1 The robotic device is positioned within the patient's body, including a device base 40, an actuable arm 42, and an end effector 46.

[0079] In this embodiment of the invention, the instrument base 40 is an axis that can be drawn from... Figure 1 The robotic platform 24 shown extends outwards, facilitating the proper positioning of the actuable arm 42 and end effector 46 relative to the patient 8. The actuable arm 42 is coupled to an instrument base 40 and includes a plurality of instrument joints 44. Each instrument joint 44 is rotatable, and rotation can be achieved by the components constituting... Figure 1A portion of the robot motor 26 shown is driven by a cable extending from the instrument platform 24, passing through the instrument base 40, and attached to an associated instrument joint 44. The end effector 46 is coupled to the actuable arm 42 and can move within the instrument workspace by rotation of one or more instrument joints 44. The current position and / or orientation of the robot instrument 22 includes the current position and / or orientation of the end effector 46.

[0080] The end effector 46 also includes a pair of clamps 48 that can move between an open configuration and a closed configuration. Figure 3 (Displayed in the middle). User 4 can manipulate... Figure 2 The gripper 38 corresponding to the passive controller 12 shown controls the opening and closing of the clamp 48.

[0081] The instrument workspace in which the end effector 46 can move is typically very different in scale from the controller workspace in which the handle 36 can move. Furthermore, the arrangement of the instrument joints 44 in the actuated arm 42 is typically very different from the arrangement of the controller joints 34 in the articulated arm 32, meaning that the shape of the instrument workspace is generally different from the shape of the control workspace.

[0082] In use, the control workspace is mapped to the instrument workspace so that when the user moves the passive controller 12 within the control workspace, the position of the robotic instrument 22 can track the position of the passive controller 12. However, due to the aforementioned differences, the control workspace cannot always be perfectly mapped to the instrument workspace. This means that the user 4 may move the handle 36 to a position within the control workspace, and the end effector 46 moving within the instrument workspace cannot replicate that position.

[0083] Figure 4 A two-dimensional illustration of the control workspace 50 mapped relative to the instrument workspace 60 is shown. In this example, the current position 52 of the passive controller in the control workspace 50 is outside the instrument workspace 60, while the current position 62 of the robot instrument in the instrument workspace 60 is as close as possible to the current controller position 52 while being within the constraints of the instrument workspace 60.

[0084] In this situation, the user can move the controller position 52 to the right, toward the current instrument position 62 indicated by arrow 53, but the instrument will remain in the same position. Therefore, from the user's perspective, the robot instrument 22 may appear to be frozen.

[0085] Device 2, in particular at least one processor, memory and computer program code, is configured to receive a recalibration command from user 4 via passive controller 12 and, in response to the recalibration command, recalibrate the mapping from control workspace 50 to instrument workspace 60 such that the current position 52 of passive controller 12 corresponds to the current position of robotic instrument 12.

[0086] Figure 5 The diagram shows a recalibrated mapping from the control workspace 50 to the instrument workspace, where the controller position 52 corresponds to the current instrument position 62. Now, if the user 4 moves the passive controller 12 to the right as indicated by arrow 54, a new instrument position corresponding to the new controller position, and the trajectory of the robot instrument 22, can be calculated to move toward the new instrument position and thus track the controller position.

[0087] Figure 6 This illustrates how the recalibration of the control workspace 50 to the instrument workspace 60 can be incorporated into the clutch program 104 of device 2. Normal control 102 indicates that device 2 is in normal use, at which point the robotic instrument 22 is tracking the position and orientation of the passive controller 12. User 4 can initiate clutch program 104 by pressing the clutch pedal.

[0088] See back Figure 1 The foot pedal controller 16 includes a clutch mechanism (not shown), which the user 4 can engage to change the position of the passive controller 12 within the control workspace without causing the robot 22 to move within the machine workspace (e.g., ...). Figure 3 The position of the robot (as shown) changes accordingly. Therefore, the engagement of the clutch mechanism causes the robot 22 to disengage from tracking the position of the passive controller 12, but its orientation may not change. During clutch control, the orientation of the robot 22 may still change depending on the orientation of the passive controller 12.

[0089] In this embodiment of the invention, the clutch mechanism includes a clutch pedal that can be pressed by the user 4 to engage the clutch mechanism and then released to disengage it. However, in other embodiments of the invention, the clutch mechanism may include any suitable means for the user to engage and disengage it, such as a button, trigger, lever, or voice command system.

[0090] exist Figure 6 In the process, when the clutch pedal is pressed, a recalibration command 106 is received, and the mapping of the control workspace 50 is recalibrated relative to the instrument workspace 60, such as... Figure 4 and Figure 5As shown in the diagram. This ensures that when device 2 is in clutch control 108, controller position 52 is aligned with instrument position 62 before any movement of passive controller 12. Initial alignment of controller position 52 with instrument position 62 improves the quality of orientation tracking during clutch control 108. This is because commands causing the robot instrument to move to track the passive controller are computed to minimize the sum of squares of position and orientation tracking errors. When the position tracking error is large (i.e., the gap between controller position 52 and instrument position 62), it can make the orientation tracking error irrelevant to the overall tracking error. Therefore, the algorithm used to compute commands issued to the robot instrument will prioritize minimizing / maintaining the position tracking error, even if the orientation tracking error increases as a result. However, recalibration reduces the position tracking error to zero by definition because the positions are now aligned. Therefore, the orientation tracking error is the only error that needs to be minimized, and the algorithm will have no incentive to allow the orientation tracking error to increase.

[0091] During clutch control 108, instrument position 62 ( Figure 4 and Figure 5 (As shown) It is no longer updated based on changes in controller position 52, so the instrument position remains stationary. Meanwhile, user 4 can freely move passive controller 12, and controller position 52 will change accordingly, which may cause controller position 52 to become misaligned with instrument position 62.

[0092] When user 4 releases the clutch pedal, thus disengaging the clutch mechanism and ending clutch control 108, another recalibration command 110 is received to recalibrate the mapping of control workspace 50 relative to instrument workspace 60, such as... Figure 4 and Figure 5 As shown in the diagram. Therefore, device 2 returns to normal control 102, and user 4 can resume position control of the robot instrument 22 after the clutch mechanism disengages, as well as orientation control maintained throughout the clutch procedure 104. Furthermore, the new (post-clutch) controller position 52 is aligned with the last known instrument position 62 determined before the clutch mechanism was engaged. This avoids user 4 getting bogged down in misalignment issues after the clutch procedure 104, and also prevents the robot instrument from immediately twitching or jumping to align with controller position 52 after the clutch mechanism disengages.

[0093] During the engagement of clutch procedure 104, user 4 maintains control over the orientation of robot device 22, particularly end effector 46, by manipulating the orientation of passive controller 12, particularly handle 36. However, in many cases, user 4 may not be able to fully control the orientation of robot device 22, at least temporarily. For example, when user 4 begins using device 2, the initial orientation of robot device 22 may differ from the orientation of passive controller 12 being held by user 4. In this case, device 2 is configured to automatically control the orientation of robot device 22 to align it with the orientation of passive controller 12.

[0094] During automatic control, device 2 determines the movement trajectory of robot tool 22 within the tool's workspace to move it from its current orientation to a desired orientation. However, since automatic control is performed after recalibration, the primary objective of automatic control can be considered as moving robot tool 22 from its current orientation to the desired orientation. The generated trajectory is sent to robot motor 26 (…). Figure 1 As shown, the motor actuates the robot 22 as needed. The device 2 is configured to stop automatically controlling the robot 22 once the current posture reaches the desired posture, thus completing the necessary alignment of the robot 22, or once a cancellation command is received. If the user 4 deems the current trajectory of the robot 22 potentially unsafe, the user 4 can initiate a cancellation command at any time during automatic control.

[0095] Device 2 is configured to limit the movement speed of the automated control robot 22 to a predetermined range during calibration. For example, the speed can be limited to a speed that allows user 4 to monitor the trajectory of the robot 22 and ensure that the trajectory is not potentially unsafe.

[0096] Since the robot 22 moves at a limited speed during automatic control, automatic control may not be able to complete in real time. Therefore, when the robot 22 is under automatic control, the user has the opportunity to manually change the position and orientation of the passive controller 12. To help avoid misalignment of the robot 22, the device can be configured to redetermine the movement trajectory when the position and orientation of the passive controller 12 change.

[0097] An example where automated control might be needed is when user 4 first controls robotic device 22. Figure 7 In this embodiment of the invention, when device 2 is activated, it enters a first uncontrolled state 112, in which there is no tracking of the position or orientation of the robotic device 22 to the position or orientation of the passive controller 12. In order for user 4 to control the robotic device 22, user needs to initiate engagement procedure 116.

[0098] The passive controller 12 includes an engagement mechanism (not shown) which includes a gripper 38. Figure 2 (Shown) and proximity sensor (not shown). The engagement mechanism is configured to initiate tracking of the robot's position and orientation to the passive controller's position and orientation upon activation by user 4.

[0099] The proximity sensor is configured to detect the presence of a user, and the device 2 is configured to initiate tracking from the robot's position to the passive controller's position only when the proximity sensor detects the presence of a user. Therefore, the first step in initiating the engagement mechanism by the user is to activate the proximity sensor, thereby causing the device 2 to enter the second uncontrolled state 114.

[0100] In this embodiment of the invention, the proximity sensor forms part of the handle 36. Figure 2 (as shown), and is configured to detect when the handle 36 is gripped by the user 4. However, in other embodiments of the invention, the proximity sensor can be any suitable type of proximity sensor configured to detect the presence of a user.

[0101] The second step for user 4 to activate the engagement mechanism is to pinch the gripper 38 (i.e., press and release), thereby initiating engagement procedure 116. This action demonstrates that user 4 has complete and conscious control over the passive controller 12.

[0102] In other embodiments of the invention, the engagement mechanism may include any suitable means for a user to initiate tracking of the robotic instrument to the passive controller, such as a button, trigger, lever, foot pedal, or voice command system. Furthermore, the engagement mechanism may require a series of actions to initiate tracking of the robotic instrument to the passive controller, such as a double-click or triple-click.

[0103] After engagement procedure 116 is initiated, a recalibration command 118 is received from the passive controller 12 to align the position of the passive controller 12 with the position of the robot 22. Then, device 2 enters automatic control state 120, where device 2 automatically controls the robot 22 to align its orientation with that of the passive controller. Once automatic control 120 is complete or user 4 triggers a cancellation command, device 2 transitions from automatic control 120 to normal (manual) control 102.

[0104] Device 2 is configured to stop the robot instrument 22 from tracking the position and orientation of the passive controller 12 when the proximity sensor detects that the user 4 is not present. Therefore, the engagement procedure 116 may be interrupted if the user 4 detaches from the proximity sensor, whether during the second uncontrolled state 114 or during automatic control 120. Furthermore, during normal control, if the user 4 detaches from the proximity sensor, device 2 will exit normal control 102. When the proximity sensor detaches, device 2 will return to the first uncontrolled state 112 until the proximity sensor is re-engaged to restart the engagement procedure 116.

[0105] Figure 8 An unlocking procedure is shown, which can be used to restart tracking of the robot's position and / or orientation to the passive controller's position and / or orientation after a tracking interruption. User 4 may initiate the unlocking procedure 122 for a variety of different reasons. For example, the robot 22 may have frozen because user 4 is moving the passive controller 12 faster than the robot's finite speed. On the other hand, the user may feel that the robot in a particular configuration has lost control because device 2 restricts the robot's permissible postures.

[0106] Figure 1 The illustrated foot pedal controller 16 may include an unlocking mechanism (e.g., an unlocking pedal) that can be pressed / engaged by the user 4 to trigger an unlocking procedure, and then released / disengaged to terminate the unlocking procedure. However, in other embodiments of the invention, the unlocking mechanism may include any suitable means for the user to engage and disengage, such as a button, trigger, lever, or voice command system.

[0107] exist Figure 8 In the process, when device 2 is in normal control 102, user 4 can initiate unlocking procedure 122 by pressing the unlock pedal. When the unlock pedal is pressed, a recalibration command 124 is received from passive controller 12 to align the position of passive controller 12 with the position of robot 22 as described above. Device 2 then enters automatic control state 126. During automatic control 126, device 2 generates a trajectory to align the posture of robot 22 as closely as possible to the posture of passive controller 12. Although the positions of robot 22 and passive controller 12 have been aligned through the preceding recalibration, the determined trajectory may involve altering the position of robot 22 if this improves the accuracy of its orientation relative to the orientation of passive controller 12, thereby making the overall posture of robot as close as possible to the posture of passive controller 12.

[0108] In an embodiment of the invention, device 2 uses an inverse kinematics (IK) algorithm to generate commands that cause the robotic instrument to track the posture of the passive controller.

[0109] Numerical IK algorithms can be divided into two subsets: global optimization algorithms and local optimization algorithms. The former focuses on the entire search space and provides the best possible solution (global solution). The latter utilizes mathematical function knowledge and searches for the optimal solution near the algorithm's initial conditions (i.e., the initial state on which further calculations are based).

[0110] Figure 9 The example shown is a global solution 202 for any function 200, which can be found using a global algorithm; it is the global minimum of the function.

[0111] Local algorithms compare the current value of a function with its neighbors and move the solution toward the smaller value. Furthermore, a local algorithm terminates when all neighbors are higher than the current solution. Figure 10 This shows two possible local solutions 204 and 206 for the same function 200 based on two different initial conditions 208 and 210. A local solution 204 is equivalent to the global solution 202. Figure 9 (as shown), while another local solution 206 is different.

[0112] If the robot 22 is in a local minimum relative to the desired robot posture set by the user 4 via the passive controller 12, then device 2 ( Figure 1 (As shown) If a local algorithm is used, it will repeatedly return the same local solution (e.g. Figure 10 (206 in the example), even if there might be better solutions (e.g. Figure 10 (204 in the text). Therefore, the robotic device will not perform any movement, and the robotic device 22 appears to be unresponsive to user 4.

[0113] Although global algorithms appear superior to local algorithms because they provide an objectively best answer, local algorithms are generally preferred because they are faster, finish in a finite amount of time, and have better smoothness. For the purposes of this disclosure, smoothness can be broadly interpreted as preventing the robotic device 22 from jumping or moving erratically.

[0114] Embodiments of the present invention find a global solution by implementing a random shooting method on the initial conditions of the local algorithm, while simultaneously benefiting from the efficiency of the local algorithm. The local algorithm is restarted multiple times using randomly selected initial conditions. Finally, only the best local solution found is returned from the algorithm.

[0115] In use, the device 2, particularly the robotic instrument 22, is subject to various limitations. Specifically, the position of the end effector 46 is confined to the instrument's workspace. Furthermore, the speed at which the end effector 46 is allowed to move may be limited based on the physical constraints of the robotic instrument 22 or a maximum speed considered safe for a particular application. To illustrate these limitations, constraints are added to the optimization problem, restricting the IK algorithm to a set of feasible solutions. Figure 11 In the given state 301, the solution is calculated using any function 300. The feasible solution is restricted by constraint condition 302 to the constrained region 304 of the arbitrary function 300. The unconstrained global solution 306 exists outside the constrained region 304 and is therefore infeasible. Meanwhile, the local solution 308 exists within the constrained region 304 and is therefore feasible. There is also a feasible constrained global solution 310, because it lies within the constrained region 304 and is superior to the unconstrained local solution 308.

[0116] exist Figure 12 In this example, a solution is computed for the new arbitrary function 400 based on the same current state 301 and the same constraint condition 302 used to provide the constrained region 404. In this example, with... Figure 11 Similarly, there exists an unconstrained global solution 406, which lies outside the constrained region 404 and is therefore infeasible. However, for any function 400, there exists a local solution 408, which is the best available solution in the constrained region 404 and is therefore a constrained global solution.

[0117] exist Figure 13 In this context, based on the same current state 301 but with the application of new constraints 502 providing a constrained region 504, a solution is computed for another arbitrary function 500. Figure 11 and Figure 12 Similarly, an unconstrained global solution 506 exists outside the constrained region 504, and is therefore infeasible. In this case, an unconstrained local solution 508 also exists outside the constrained region 504. Within the constrained region 504, there exists a constrained local solution 510, which is the best available solution in the constrained region 504, and is therefore both a constrained global solution and a constrained local solution.

[0118] In embodiments of the present invention, the IK algorithm includes predetermined positional constraints to enable computation of partially constrained poses of the robot 22 that satisfy the positional constraints. The positional constraints may be based on the device's workspace, which in turn is based on the physical constraints of the robot 22. Figure 3 For example, the length of the robotic device 22, the range of motion of each joint 44, and the position of each joint 44 along the length of the robotic device 22. To ensure that any solution calculated by the IK algorithm is physically feasible, positional constraints are always applied while the device 2 is in use, such that all solutions are partially constrained.

[0119] The IK algorithm may further include predetermined speed limits to enable computation of constrained postures of the robot 22 that simultaneously satisfy both position and speed constraints. The predetermined speed limits may be based on the maximum speed of the robot 22 considered safe, and allow the user to monitor movement, determine the trajectory, and cancel movement if it may become unsafe.

[0120] Under normal conditions, when device 2 is in use, robot 22 will be constrained to a constrained posture that satisfies both position and velocity constraints. Under these conditions, the IK algorithm is used to compute the constrained global solution, i.e., the best possible solution with constraints applied. However, the IK algorithm can also compute partially constrained global solutions simultaneously, which are only limited by position constraints.

[0121] Activation of the unlocking mechanism causes device 2 to check whether the current constrained pose of the robot based on the constrained global solution calculated by the IK algorithm is equivalent to the partially constrained pose based on the simultaneously calculated partially constrained global solution, i.e., the best available solution within the robot's positional constraints. If not, the device will move the robot to the partially constrained pose.

[0122] To prevent sudden, unintended movement of the robotic device 22 when the unlocking mechanism is activated, the speed of automatic control can be limited, as described above. Once the determined trajectory is completed, device 2 then returns to normal control 102.

[0123] The unlocking procedure 122 runs when the user comes into contact with the passive controller 12, therefore the passive controller is likely to be moved when automatic control 126 occurs. To avoid mismatch between the position and / or orientation of the passive controller 12 and the robotic device 22, the determined trajectory is updated throughout the unlocking procedure, as described above. Furthermore, if the unlocking foot pedal is released at any time before the device 2 returns to normal control 102, the device 2 immediately returns to normal (manual) control 102. Therefore, as... Figure 7 As shown, releasing the unlock pedal is equivalent to triggering the cancel command.

[0124] In an embodiment of the invention, the robot device 22 may be configured to rearrange itself between an initial posture and one or more other postures, and the device 2 may be configured to automatically control the arrangement of the robot device 22 so that it returns from one or more other postures to the initial posture when the homing mechanism is activated.

[0125] In these embodiments, the initial posture of the robotic device 22 may be a combination of the rotational positions of each joint 44 that forms part of the robotic device 22, which are held when the robotic device 22 is inactive. For example, the initial posture may correspond to a linear arrangement of the joints 44 (e.g., Figure 3 (As shown), this is advantageous for inserting or removing the robotic instrument 22 from the surgical site. The initial posture can also correspond to the neutral arrangement of the joint 44, from which the robotic instrument 22 can be easily moved to any position and orientation within the instrument workspace.

[0126] The repositioning mechanism provides a means to automatically return the robotic instrument 22 from any other posture it may have moved into during use to its initial posture. This can be very useful, for example, when a surgeon has completed surgery and is ready to withdraw the robotic instrument 22 from the surgical site, or when a part of a surgery has been completed and the surgeon wishes to begin the next stage of the procedure with the robotic instrument 22 in a neutral position.

[0127] The resetting mechanism may include a clutch pedal and an unlock pedal, and can be activated by pressing the clutch pedal and unlock pedal in a predetermined sequence. Figure 14 In the middle, user 4 can initiate the return procedure 130 by first pressing the clutch pedal. According to Figure 6 The clutch procedure 104 shown involves pressing the clutch pedal, which triggers a recalibration command 106, and the mapping of the control workspace 50 relative to the instrument workspace 60 is recalibrated. Figure 4 and Figure 5 As shown in the diagram. Device 2 will then enter clutch control 108. While clutch control 108 is active, user 4 can press and release the foot pedal within 3 seconds and press it again to initiate return procedure 130.

[0128] In other embodiments of the invention, the homing mechanism includes any suitable measures that can be activated by the user, such as a separate foot pedal, button, trigger, lever, or voice command. Furthermore, different combinations or sequences of user interaction with other measures, such as a clutch pedal and an unlock pedal, can also be used to initiate the homing procedure 130, and different time periods can be provided for the combinations or sequences of actions to be taken.

[0129] Once the repositioning procedure 130 is initiated, device 2 begins to automatically control 132, similar to... Figure 7 and Figure 8 The automatic controls 120 and 126 shown, in addition to determining the movement trajectory of the robot 22 to move it to its initial position, also allow the device 2 to be configured to limit the movement speed of the robot 22 to a predetermined range when it returns to its initial position.

[0130] and Figure 7 In contrast to the automatic control 120 shown, once the trajectory is completed, or the user 4 triggers a cancellation command by releasing the clutch pedal or unlocking the pedal, device 2 enters [the following state / phase]. Figure 7 The second uncontrolled state 114 is shown. To allow user 4 to regain control of the robotic device, they must squeeze gripper 38 to initiate operation. Figure 7 The engagement procedure 116 is shown. This is because, during the robot's initial orientation, the robot 22 may have become severely misaligned with the passive controller 12.

[0131] Figure 15 A possible process flow is shown, which allows device 2 to perform... Figures 6 to 8 and Figure 14 The operations shown are as follows. According to... Figure 7 Device 2 is configured to stop the robot instrument 22 from tracking the position and orientation of the passive controller 12 when the proximity sensor detects that the user 4 is not present. Therefore, if the user 4 disengages from the proximity sensor during the second uncontrolled state 114 or during automatic control 120 / 126, the engagement procedure 116 / unlock procedure 122 may be interrupted. Furthermore, during normal control, if the user 4 disengages from the proximity sensor, device 2 will exit normal control 102. Additionally, during the homing procedure 130, if the user disengages from the proximity sensor, device 2 will exit automatic control 132. In each case, when the proximity sensor disengages, device 2 will return to the first uncontrolled state 112 until the proximity sensor is re-engaged to restart the engagement procedure 116.

[0132] The applicant hereby discloses each individual feature described herein, as well as any combination of two or more such features, provided that such features or combinations can be implemented in their entirety based on this specification, given the common sense of those skilled in the art, regardless of whether such features or combinations of features solve any problem disclosed herein, and without limiting the scope of the claims. The applicant notes that the disclosed aspects / embodiments may consist of any such individual features or combinations of features. In view of the foregoing description, those skilled in the art will readily appreciate that various modifications can be made within the scope of this disclosure.

Claims

1. An apparatus, characterized in that, include: At least one processor; as well as At least one memory including computer program code, said at least one memory and computer program code being configured to cause the device using said at least one processor: A recalibration command is received from a passive controller configured to remotely control a robotic instrument, wherein the passive controller and the robotic instrument have degrees of freedom of movement in their respective control workspaces and instrument workspaces, and wherein the control workspace is mapped to the instrument workspace to allow the position of the robotic instrument to track the position of the passive controller as the passive controller moves within the control workspace. as well as In response to the recalibration command, the mapping from the control workspace to the instrument workspace is recalibrated so that the current position of the passive controller corresponds to the current position of the robot instrument. The passive controller includes an engagement mechanism configured to initiate tracking from the robot's position to the passive controller's position, and wherein the recalibration command is received from the passive controller upon activation of the engagement mechanism. The passive controller includes an unlocking mechanism configured to restart tracking from the robot's position to the passive controller's position after a tracking interruption, and wherein the recalibration command is received from the passive controller upon activation of the unlocking mechanism. The orientation of the robotic instrument tracks the orientation of the passive controller, and the device is configured to automatically control the orientation of the robotic instrument so that it aligns with the orientation of the passive controller when the engagement mechanism or the unlocking mechanism is activated. The device is configured to determine the movement trajectory of the robot within the instrument workspace based on the current orientation of the passive controller, in order to achieve the automatic control; The device is configured to redetermine the movement trajectory when the current orientation of the passive controller changes.

2. The apparatus according to claim 1, characterized in that, The passive controller includes a clutch mechanism configured to allow the position of the passive controller to change within the control workspace without causing a corresponding change in the position of the robot instrument within the instrument workspace, and wherein the recalibration command is received from the passive controller when the clutch mechanism is engaged or subsequently disengaged.

3. The apparatus according to claim 1, characterized in that, The robotic instrument is configured to rearrange itself between an initial posture and one or more other postures, and the means is configured to automatically control the rearrangement of the robotic instrument so that it returns from the one or more other postures to the initial posture upon activation of a homing mechanism.

4. The apparatus according to claim 3, characterized in that, The device is configured to limit the movement speed of the robotic instrument to a predetermined range during alignment / arrangement.

5. The apparatus according to claim 3, characterized in that, The device is configured to stop automatically controlling the robotic instrument upon receiving a cancellation command, or once alignment / arrangement is complete.

6. The apparatus according to claim 1, characterized in that, The engagement mechanism includes a proximity sensor configured to detect the presence of a user, and wherein the device is configured to initiate tracking of the robot's position to the passive controller's position only when the proximity sensor detects the presence of a user.

7. The apparatus according to claim 6, characterized in that, The device is configured to stop the robotic instrument from tracking the position of the passive controller when the proximity sensor detects that the user is not present.

8. The apparatus according to claim 1, characterized in that, The passive controller includes an electronic display screen configured to display a diagram of the instrument workspace and control workspace, and wherein the device is configured to control the electronic display screen such that the current position and / or orientation of the robotic instrument and the passive controller are indicated within the diagram of their respective instrument workspace and control workspace.

9. The apparatus according to claim 8, characterized in that, The device is configured to control the electronic display screen such that the current position and / or orientation is indicated in a two-dimensional or three-dimensional manner.

10. The apparatus according to claim 1, characterized in that, The current position and / or orientation of the passive controller and the robotic instrument are respectively the last known position and / or orientation of the passive controller and the robotic instrument with respect to the device.

11. The apparatus according to claim 1, characterized in that, The robotic instrument includes an end effector, and the current position and / or orientation of the robotic instrument is the current position and / or orientation of the end effector.

12. The apparatus according to claim 1, characterized in that, The robotic instrument is a surgical robotic instrument.

13. The apparatus according to claim 1, characterized in that, The device includes the passive controller and / or robotic instrument.

14. A computer-implemented method, characterized in that, include: A recalibration command is received from a passive controller configured to remotely control a robotic instrument, wherein the passive controller and the robotic instrument have degrees of freedom of movement in their respective control workspaces and instrument workspaces, and wherein the control workspace is mapped to the instrument workspace to allow the position of the robotic instrument to track the position of the passive controller as the passive controller moves within the control workspace. as well as In response to the recalibration command, the mapping from the control workspace to the instrument workspace is recalibrated so that the current position of the passive controller corresponds to the current position of the robot instrument. The recalibration command is received from the passive controller when the engagement mechanism of the passive controller is activated, wherein the engagement mechanism is configured to initiate tracking from the robot's position to the passive controller's position; or, The recalibration command is received from the passive controller when the unlocking mechanism of the passive controller is activated, wherein the unlocking mechanism is configured to restart tracking from the robot instrument position to the passive controller position after tracking is interrupted; When the orientation of the robot tracks the orientation of the passive controller, the orientation of the robot is automatically controlled so that it aligns with the orientation of the passive controller when the engagement mechanism or the unlocking mechanism is activated. The robot's trajectory within the workspace is determined based on the current orientation of the passive controller to achieve the automatic control. as well as When the current orientation of the passive controller changes, the movement trajectory is redefined.

15. A computer program, characterized in that, Includes computer code configured to perform the method of claim 14.

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