Double-brake assembly joint

Abstract

The invention relates to a dual brake assembly joint. A system, such as a computer-assisted medical system, includes a first link, a second link, a joint, and a dual brake assembly. The first link has a first end and a second end. The second link has a first end and a second end. A joint is connected to the second end of the first link and the first end of the second link. A dual brake assembly is coupled to the first link and the second link. The dual brake assembly includes a first brake and a second brake. Braking provided by the dual brake assembly reduces relative movement between the first link and the second link.

Description

[0001] This application is a divisional application of Chinese patent application 2019800047808 (PCT / US2019 / 024787) entitled “Dual Brake Assembly Joint” filed on March 29, 2019.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application is related to and claims priority to U.S. Provisional Application No. 62 / 649,835, filed on March 29, 2018, entitled “Dual Brake Setup Joint,” the contents of which are incorporated herein by reference. Technical Field

[0004] The present invention relates generally to computer assisted medical systems and, more particularly, to joint actuators for computer assisted medical systems. Background Art

[0005] The teleoperation system 100 is a computer-assisted medical system (e.g., a minimally invasive surgical system) that includes an endoscopic imaging system 192, a surgeon's console 194 (master device), and a patient-side support system 110 (slave device), all of which are interconnected by wired (electrical or optical) connections or wireless connections 196. One or more electronic data processors can be positioned in these major components in various ways to provide system functionality. Examples are disclosed in U.S. Pat. No. 9,060,678 B2.

[0006] The imaging system 192 performs image processing functions on, for example, captured endoscopic imaging data of the surgical site and / or preoperative or real-time image data from other imaging systems external to the patient. The imaging system 192 outputs the processed image data (e.g., images of the surgical site and related control and patient information) to the surgeon at the surgeon console 194. In some aspects, the processed image data is output to an optional external monitor visible to other operating room personnel or to one or more locations remote from the operating room (e.g., a surgeon at another location can monitor the video; a real-time feed of video can be used for training; etc.).

[0007] The surgeon console 194 includes a multi-degree-of-freedom ("DOF") mechanical input device ("master device") that allows the surgeon to manipulate instruments, entry guide device(s), and imaging system devices, collectively referred to as slave devices. In certain aspects, these input devices can provide tactile feedback to the surgeon from instruments and surgical device assembly components. The console 194 also includes a stereoscopic video output display that is positioned so that the image on the display is generally focused at a distance that corresponds to the surgeon's hands working behind / below the display screen. These aspects are discussed in U.S. Patent No. 6,671,581.

[0008] The base 101 of the patient side support system 110 supports an arm assembly that includes a passive setup arm assembly 120 and an actively controlled manipulator arm assembly 130. The actively controlled manipulator arm assembly 130 is referred to as an entry guide manipulator 130.

[0009] In one example, the assembly arm assembly 120 includes two passive rotational assembly joints 103 and 105. If the joint brakes of the assembly joints 103 and 105 are released, the rotational assembly joints 103 and 105 allow manual positioning of the coupled assembly links 104 and 106. Alternatively, some of these assembly joints can be actively controlled, and more or fewer assembly joints can be used in various configurations. The assembly joints 103 and 105 and the assembly links 104 and 106 allow personnel to place the entry guide manipulator 130 in various positions and orientations in Cartesian x, y and z space. Specifically, the assembly joints 103 and 105 allow positioning in the (x, y) plane, and the assembly link 104 allows positioning in the z dimension. In particular, the prismatic assembly joint (not shown) between the assembly link 104 and the base 101 of the assembly arm assembly 120 can be used for vertical adjustment 112.

[0010] 1 , the manipulator assembly yaw joint 111 is coupled between one end of the mounting link 106 and a first end (e.g., a proximal end) of the first manipulator link 113. The yaw joint 111 allows the first manipulator link 113 to move relative to the mounting link 106 in a motion that can be arbitrarily defined as "yaw" about a manipulator assembly yaw axis 123. As shown, the axis of rotation of the yaw joint 111 is aligned with a remote center of motion 146, which is typically the location where the instrument enters the patient's body (e.g., at the navel for abdominal surgery).

[0011] In one embodiment, the mounting link 106 is rotatable in a horizontal plane or an x, y plane, and the yaw joint 111 is configured to allow a first manipulator link 113 (sometimes referred to as link 113) in the entry guide manipulator 130 to rotate about a yaw axis 123. The mounting link 106, yaw joint 111, and first manipulator link 113 provide a constant vertical yaw axis 123 for the entry guide manipulator 130, as indicated by a vertical line passing through the yaw joint 111 to the remote center of motion 146.

[0012] The distal end of the first manipulator link 113 is coupled to the proximal end of a second manipulator link 115 (sometimes referred to as link 115) via a first actively controlled revolute joint 114. The distal end of the second manipulator link 115 is coupled to the proximal end of a third manipulator link 117 (sometimes referred to as link 117) via a second actively controlled revolute joint 116. The distal end of the third manipulator link 117 is coupled to the distal end of a fourth manipulator link 119 (sometimes referred to as link 119) via a third actively controlled revolute joint 118.

[0013] In one embodiment, links 115, 117, and 119 are coupled together to act as a coupled kinematic mechanism. Coupled kinematic mechanisms are well known (e.g., when the input and output link motions remain parallel to each other, such mechanisms are referred to as parallel kinematic linkages). For example, if revolute joint 114 is actively rotated, then joints 116 and 118 are also actively rotated so that link 119 moves in a constant relationship to link 115. Thus, it can be seen that the axes of rotation of joints 114, 116, and 118 are parallel. When these axes are perpendicular to the rotational yaw axis 123 of yaw joint 111, links 115, 117, and 119 move relative to link 113 in a motion that can be arbitrarily defined as "pitch" about the pitch axis of the manipulator assembly.

[0014] In this regard, the manipulator pitch axis extends into and out of the page of FIG. 1 at the remote center of motion 146. Movement about the manipulator assembly pitch axis is represented by arrow 121. Because the links 115, 117, and 119 move as a single assembly, the first manipulator link 113 may be considered an active proximal manipulator link, while the second through fourth manipulator links 115, 117, and 119 may be collectively considered active distal manipulator links.

[0015] An entry guide manipulator assembly platform 132 (sometimes referred to as platform 132) is coupled to the distal end of the fourth manipulator link 119. An entry guide manipulator assembly 133 is rotatably mounted on the platform 132. The entry guide manipulator assembly 133 includes an instrument manipulator positioning system.

[0016] Entry guide manipulator assembly 133 rotates multiple instrument manipulator assemblies 140 in groups about axis 125. Specifically, entry guide manipulator assembly 133 rotates as a single unit relative to platform 132 in a motion arbitrarily defined as "roll" about entry guide manipulator assembly roll axis 125 (sometimes referred to as axis 125).

[0017] Each of the plurality of instrument manipulator assemblies 140 is coupled to entry guide manipulator assembly 133 by a different insertion assembly 135 (also referred to as an "insertion mechanism 135"). In one aspect, each insertion assembly 135 is a telescoping assembly that moves the corresponding instrument manipulator assembly away from and toward entry guide manipulator assembly 133. In FIG1 , each insertion assembly is in a fully retracted position.

[0018] Each of the plurality of instrument manipulator assemblies includes a plurality of motors that drive a plurality of output members in an output interface of the instrument manipulator assembly. For an example of an instrument manipulator assembly and a surgical instrument that can be coupled to the instrument manipulator assembly, see U.S. Patent Application Publication No. US2016 / 0184037A1.

[0019] The joint brakes for rotating the assembly joints 103 and 105 are single brakes that perform multiple functions, respectively. As described above, during assembly, the joint brakes of the assembly joints 103 and 105 are released to allow manual positioning of the coupled assembly links 104 and 106.

[0020] To help ensure that the assembly joints 103 and 105 do not accidentally move in the event of a fault, the joint brake is a power-off brake, i.e., a brake that requires power to physically disengage in normal operation. To help ensure that surgical tools can still be pushed out of the way to access the patient during an emergency, a maximum torque that can be applied by a single joint brake is specified, which is called the egress torque. Above this egress torque, the joint brake will slip.

[0021] To reduce or minimize vibration of the end effector (e.g., cannula and instrument tip) during a procedure, the forces or torques applied by the stationary assembly joints (e.g., assembly joints 103 and 105) oppose the forces or torques required to accelerate and decelerate components physically coupled between the assembly joints and the end effector (e.g., entry guide manipulator 130). For procedures performed using patient-side support system 110, the torques required at assembly joints 103 and 105 during the procedure are applied by using joint brakes in each joint. Summary of the invention

[0022] A system (e.g., a computer-aided medical system) includes a first connecting rod, a second connecting rod, a joint, and a dual brake assembly. The first connecting rod has a first end and a second end. The second connecting rod has a first end and a second end. The joint is connected to the second end of the first connecting rod and the first end of the second connecting rod. The dual brake assembly is coupled to the first connecting rod and the second connecting rod. The dual brake assembly includes a first brake and a second brake. The braking provided by the dual brake assembly reduces the relative motion between the first connecting rod and the second connecting rod.

[0023] In one aspect, the first brake provides a first brake holding strength when physically engaged, and the second brake provides a second brake holding strength when physically engaged. The second brake holding strength is different from the first brake holding strength, and in one aspect, the second brake holding strength is greater than the first brake holding strength.

[0024] In another aspect, the first brake is physically engaged when unpowered, and the second brake is physically disengaged when unpowered. The first brake is implemented as an actuator brake, and the second brake is implemented as a joint brake.

[0025] If the system is in a power-off state, the first brake is not powered and is physically engaged, and the second brake is not powered and is physically disengaged. If the system is in a fault state, the controller physically engages the first brake and physically disengages the second brake. If the system is in a clutch mode, the controller physically disengages the first brake and physically disengages the second brake. During the procedure, the controller physically disengages the first brake and physically engages the second brake.

[0026] In another aspect, the system includes an actuator and a controller. The actuator is coupled to the joint. Actuation of the actuator causes the joint to move the second link relative to the first link. The controller is configured to: when the actuator fails in a state configured to move the second link relative to the first link, physically engage the first brake and physically engage the second brake to limit the movement of the second link relative to the first link.

[0027] In another aspect, the first brake and the second brake include a single brake. The system further includes an actuator having a housing and a shaft extending from the housing. The single brake is coupled to the actuator housing and the shaft. In a first state, the single brake has a first holding strength, and in a second state, the single brake has a second holding strength. The first holding strength is different from the second holding strength.

[0028] A single brake includes a brake rotor, a caliper, and a variable load assembly. The brake rotor is mounted on a shaft. The caliper is coupled to a housing. The variable load assembly is coupled to the caliper. In a first state, the variable load assembly applies a first force on the caliper, and in a second state, the variable load assembly applies a second force on the caliper. The first force is different from the second force.

[0029] In another aspect, a controller is coupled to the first brake and the second brake, and the controller is configured to:

[0030] Physically disengaging the first brake and physically disengaging the second brake to allow the second link to move freely relative to the first link; and physically engaging the first brake and physically disengaging the second brake to restrict movement of the second link relative to the first link; and

[0031] During a procedure performed using the system, the first brake is physically disengaged and the second brake is physically engaged; and when the actuator fails in a state configured to move the second link relative to the first link, the first brake is physically engaged and the second brake is physically engaged to limit movement of the second link relative to the first link.

[0032] A method of controlling the movement of a second link relative to a first link in a system includes: physically disengaging a first brake and physically disengaging a second brake to allow the second link to move freely relative to the first link, and physically engaging the first brake and physically disengaging the second brake to limit the movement of the second link relative to the first link. The method also includes: physically disengaging the first brake and physically engaging the second brake during a procedure performed using the system; and physically engaging the first brake and physically engaging the second brake to limit the movement of the second link relative to the first link when an actuator fails in a state configured to move the second link relative to the first link.

[0033] A computer-assisted medical system includes a patient-side support system. The patient-side support system includes a controller, a first link, a second link, and a joint assembly. The first link has a first end and a second end. The second link has a first end and a second end. The joint assembly is connected to the second end of the first link and the first end of the second link.

[0034] The joint assembly includes an actuator and a dual brake assembly. The actuator is configured to cause the joint assembly to move the second link relative to the first link. The dual brake assembly is coupled to the first link, the second link and the actuator. The dual brake assembly includes a first brake and a second brake.

[0035] A controller is coupled to the actuator and the dual brake assembly. The controller is configured to command the dual brake assembly to reduce relative motion between the first link and the second link.

[0036] In this aspect, the first brake provides a first brake holding strength when physically engaged, and the second brake provides a second brake holding strength when physically engaged. The second brake holding strength is different from the first brake holding strength, and in one aspect, the second brake holding strength is greater than the first brake holding strength.

[0037] Also in this aspect, the first brake is physically engaged when not powered, and the second brake is physically disengaged when not powered. The first brake is implemented as an actuator brake, and the second brake is implemented as a joint brake.

[0038] If the computer-assisted medical system is in a power-off state, the first brake is not powered and is physically engaged, and the second brake is not powered and is physically disengaged. If the computer-assisted medical system is in a system failure state, the controller physically engages the first brake and physically disengages the second brake. If the computer-assisted medical system is in a clutch mode, the controller physically disengages the first brake and physically disengages the second brake.

[0039] During the procedure, the controller physically disengages the first brake and physically engages the second brake. Alternatively, the second brake may also be engaged only during movement of a distal component of the computer-assisted medical system where the distal component generates a torque greater than the torque that can be offset by the actuator. When the component of the computer-assisted medical system is relatively stationary or moves at a torque less than the torque controllable by the actuator, the actuator at the joint is sufficient to offset the torque required to accelerate the distal component and therefore the second brake is physically disengaged. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] FIG. 1 is a diagram of a prior art computer-assisted teleoperation surgery system.

[0041] Figure 2 is an illustration of a computer-aided medical system including a joint and a dual brake assembly.

[0042] FIG. 3A to FIG. 3E Schematic diagrams of various embodiments of a portion of a system including a first link, a second link, and a joint assembly including a joint and a dual brake assembly.

[0043] Figure 4A is a first state diagram of a controller for controlling the state of a dual brake assembly.

[0044] Figure 4Bis a second state diagram of a controller for controlling the state of a dual brake assembly.

[0045] FIG. 5A to FIG. 5C is an illustration of a dual brake assembly implemented using a single brake.

[0046] Figure 6 yes Figure 2 A cross-sectional view of an embodiment of a shoulder joint assembly.

[0047] In the drawings, for a single-digit figure number, the first digit in the element's reference number is the figure number in which the element first appears. DETAILED DESCRIPTION

[0048] Here, computer-assisted medical systems ( Figure 2 ) is first used as an example of a system including a dual brake assembly having two parts. The first part provides a first brake holding strength when physically engaged, and the second part provides a second brake holding strength when physically engaged. In one aspect, the second brake holding strength is different from the first brake holding strength. In one aspect, the second brake holding strength is greater than the first brake holding strength. Herein, the brake holding strength is sometimes referred to as holding strength. In various embodiments, the holding strength includes one or more forces, torques (or moments), combinations of forces or torques, etc. The use of the patient-side support system 210 is illustrative only and is not intended to limit the use of the dual brake assembly to this one application. As described more fully below, the dual brake assembly can be used in a variety of systems.

[0049] In one aspect, the joint assembly 203 in the patient side support system 210 includes a joint and a dual brake assembly 205. The joint rotatably couples the first link 202 to the second link 204. The dual brake assembly 205 provides the necessary braking function during all phases of operation of the computer-assisted medical system 200 without the compromise required by prior art systems having a single brake assembly associated with the joint. Sometimes, the dual brake assembly 205 is referred to as the brake assembly 205.

[0050] In one aspect, the dual brake assembly 205 of the joint assembly 203 includes two parts. The first part provides a first brake holding strength when physically engaged, and the second part provides a second brake holding strength when physically engaged. In one aspect, the second brake holding strength is different from the first brake holding strength. In one aspect, the second brake holding strength is greater than the first brake holding strength.

[0051] During a procedure performed using the computer-assisted medical system 200, in one aspect, the second portion of the dual brake assembly 205 is engaged to prevent the second link 204 from moving relative to the first link 202. This limits the movement of the yaw axis 223 of the patient-side support system 210 relative to the rotation axis 209 of the joint assembly 203, which in turn minimizes vibration during the procedure. The rotation axis 209 of the joint assembly 203 is parallel to the yaw axis 223.

[0052] In prior art systems, since a single brake is utilized to obtain the necessary holding strength during a procedure, the exit torque is increased such that, in some cases, an average of two people are required to apply the force required to slip a single brake (the number of people required depends on their individual thrust). The maximum holding strength of the brake during a procedure is still limited because it requires the user to be able to slip the brake in an emergency. In contrast, the brake holding strength of the second portion of the dual brake assembly 205 can be made as large as possible to attenuate vibrations during a procedure because the dual brake assembly 205 decouples the requirement for maximum holding strength during a procedure from the requirement that the user be able to slip the dual brake assembly 205 when needed.

[0053] For example, if the computer-assisted medical system 200 enters a fault state, the controller 290 disengages the second portion of the dual brake assembly 205 in the joint assembly 203 and engages the first portion of the dual brake assembly 205. This releases the high brake holding strength of the second portion of the dual brake assembly 205 and physically engages the smaller brake holding strength of the first portion of the dual brake assembly 205. Engaging the first portion of the dual brake assembly 205 in the fault state ensures that the second link 204 will not move accidentally, such as due to gravity. The fault state may be triggered by many environmental and operating parameters, including unexpected system operation, system movement that deviates from the commanded movement, operator input or lack of input, power outage, emergency situation, etc. The holding strength of the first portion of the dual brake assembly 205 allows the user to push the second link 204 away in an emergency so that the patient can be accessed.

[0054] As explained more fully below, in one aspect, when the master clutch is commanded to be activated, the dual brake assembly 205 is physically disengaged from all braking capacity in the joint assembly 203 so that the second link 204 can move freely relative to the first link 202. In this aspect, the first link 202 is proximal to the second link 204 and can therefore be referred to as a proximal link. In this case, the second link 204 would be a distal link. In one aspect, when the master clutch activation is terminated, the dual brake assembly engages the braking capacity in the joint assembly 203 to limit the movement of the second link 204 relative to the first link 202, e.g., a second portion of the dual brake assembly 205 is physically engaged.

[0055] On the other hand, when the master clutch activation is terminated, all braking capabilities of the dual brake assembly 205 remain disengaged. The controller uses the actuator in the joint assembly 203 to limit the movement of the second link 204 relative to the first link 202 until the actuator is insufficient to reduce vibration or the actuator is not important to reduce vibration, for example, when a command is issued to move into the guide actuator 230 and a holding strength greater than the strength that the actuator can provide is required, the controller issues a command to physically engage the second portion of the dual brake assembly 205. Therefore, in this aspect, the dual brake assembly 205 is not engaged until the dual brake assembly 205 is needed to control vibration.

[0056] To help ensure that the joints in the joint assembly 203 do not accidentally move when power is removed, a first portion of the dual brake assembly 205 is engaged, thereby limiting the movement of the second link 204 relative to the first link 202. This helps ensure that the links in the patient side support system 210 remain in a desired position during transport (e.g., moving the system to another room or other location within a room), for example.

[0057] Due to the limitations on the holding strength of a single brake, the two portions of the dual brake assembly 205 provide capabilities that were not previously achievable in joints with a single brake. As previously discussed, the brake holding strength of a single brake when engaged must be such that application of an exit torque / force will cause the brake to slip. (Here, exit torque / force means: if a rotary joint is used, one or more persons apply an exit force to the connecting rod distal to the rotary joint, thereby applying an exit torque to the rotary joint, and if a prismatic joint is used, the exit force is applied by one or more persons to the connecting rod distal to the prismatic joint.) This limits the holding strength that can be used to minimize vibration during a procedure, as well as the holding strength that can be used to stop situations where the joint actuator fails in an active state (such as a motor runaway situation).

[0058] For example, in the teleoperation system 100, the inertia of the entry guide manipulator 130 is large due to its size, mass, and mechanical design, so the torque required to accelerate the entry guide manipulator 130 about the yaw axis 123 must be sufficient to overcome the inertia of the entry guide manipulator 130. Since the yaw axis 123 and the shoulder axis 109 are parallel, the torque at the yaw axis 123 is reacted by a torque of similar magnitude at the shoulder axis 109. For certain movements of the entry guide manipulator 130, the reaction load torque is large enough that the braking torque requirement of the assembly joint 103 will exceed the allowable exit torque, so a single unassisted braking solution cannot have an exit torque, and also counteract the torque on the yaw axis 123 that may introduce vibration.

[0059] The configuration of the computer-assisted medical system 200 is similar to the teleoperation system 100 in that a torque sufficient to overcome the inertia of the entry guide manipulator 230 is required to accelerate the entry guide manipulator 230 about the yaw axis 223. Since the yaw axis 223 and the shoulder axis 209 are parallel, the torque at the yaw axis 223 is reacted by a torque of similar magnitude at the shoulder axis 209. However, the two portions of the dual brake assembly 205 allow the dual brake assembly 205 to provide the braking capability required to minimize vibration during the procedure while ensuring that the torque required to move the entry guide manipulator 230 does not exceed the exit torque at other times. Similarly, the dual brake assembly 205 is configured to counteract the failure of the joint actuator in the active state (e.g., a motor runaway condition), thereby limiting the movement of the second link 204 relative to the first link 202. Therefore, the dual brake assembly 205 provides a range of capabilities that are not available in the teleoperation system 100.

[0060] Before considering the dual brake assembly 205 in more detail, the computer-assisted medical system 200 will be described more completely. The patient-side support system 210 is part of the computer-assisted medical system, which includes a controller 290, an operator console 294, and an endoscopic imaging system 292. The controller 290, the operator console 294, and the endoscopic imaging system 192 are interconnected to the patient-side support system 210 and to each other via a wired (electrical or optical) connection or a wireless connection.

[0061] The base 201 of the patient side support system 210 supports an arm assembly that includes an actively controlled assembly arm assembly 220 and an actively controlled manipulator arm assembly 230. The actively controlled manipulator arm assembly 230 is referred to as an entry guide manipulator 230. Here, actively controlled means that the device is under the control of a controller.

[0062] In this example, the assembly arm assembly 220 includes a first link 202 (a first assembly link in this example), a joint assembly 203, a second link 204 (a second assembly link in this example), and a third link 206 (which is a third assembly link). The first prismatic joint (not visible) moves the first link 202 into and out of the base 201, i.e., moves the first link 202 in the first direction and the second direction to adjust the vertical height of the second link 204 and the third link 206, and thereby adjusts the vertical height of the entry guide manipulator 230. The joint assembly 203 (which may also be referred to as a shoulder joint assembly or a swivel joint assembly in this example) allows for rotational positioning of the coupled second link 204 and the third link 206. The second prismatic joint (not visible) moves the third link 206 into and out of the second link 204, i.e., moves the third link 206 in the third direction and the fourth direction to adjust the horizontal position of the entry guide manipulator 230.

[0063] The structure of the entry guide manipulator 230 is similar to the above-mentioned entry guide manipulator 130. Specifically, the configuration and operation of the links 213, 215, 217 and 219, joints 214, 216 and 218, platform 232, entry guide manipulator assembly, insertion assembly and multiple instrument manipulator assembly 240 of the patient side support system 210 are the same as the configuration and operation of the links 113, 115, 117 and 119, joints 114, 116 and 118, platform 132, entry guide manipulator assembly 133, insertion assembly 135 and multiple instrument manipulator assembly 140 of the patient side support system 110. Therefore, with respect to the configuration and operation of the links 213, 215, 217 and 219, the platform 232, the entry guide manipulator assembly, the insertion assembly, and the multiple instrument manipulator assemblies 240 of the patient-side support system 210, the configuration and operation of the links 113, 115, 117 and 119, the joints 114, 116 and 118, the platform 132, the entry guide manipulator assembly 133, the insertion assembly 135, and the multiple instrument manipulator assemblies 140 of the patient-side support system 110 will not be repeatedly described herein.

[0064] Controller 290 is connected to each active control joint in patient-side support system 210, to actuators that control the operation of the insertion assembly, and to the plurality of instrument manipulator assemblies 240. Herein, when it is stated that controller 290 performs an action, it means that controller 290 issues a command or signal to a component, and the component performs the action in response to the command or signal.

[0065] Herein, reference is made to and described as a single controller. Although described as a single controller, it should be understood that the controller may actually be implemented by any one or any combination of hardware, software executed on a processor, and firmware. Moreover, as described herein, the functions of the controller may be performed by one unit or divided among different components, each of which may be implemented by any one or any combination of hardware, software executed on a processor, and firmware. When divided among different components, the components may be centralized in one location or distributed in the computer-assisted medical system for the purpose of distributed processing.

[0066] A processor should be understood to include at least a logic unit and a memory associated with the logic unit. Therefore, in various embodiments, the controller system includes programming instructions (e.g., a non-temporary machine-readable medium storing instructions) for implementing some or all of the methods described according to the various aspects disclosed herein. Any of a variety of centralized or distributed data processing architectures can be adopted. Similarly, the programming instructions can be implemented as multiple separate programs or subroutines, or they can be integrated into multiple other aspects of the system described herein. In some embodiments, the controller system supports wireless communication protocols such as Bluetooth, infrared data communication (IrDA) protocol, home radio frequency (HomeRF) protocol, IEEE802.11 protocol, digital enhanced wireless communication (DECT) protocol, and wireless telemetry protocol.

[0067] As described above, the dual brake assembly 205 is included in a shoulder joint assembly that includes a rotary joint. However, the novel dual brake assembly is not limited to use in a rotary joint. The dual brake assembly can also be used in, for example, a prismatic joint.

[0068] Moreover, the dual brake assembly can be used in active control joints and passive joints. An active control joint is a joint that includes an actuator (e.g., a motor) that is configured to move the active control joint or assist in the movement of the active control joint, and the active control joint couples one link to another link. The controller uses the actuator to move one link relative to the other link. Although a passive joint also couples one link to another link, the passive joint does not include an actuator configured to move the passive joint. Therefore, in order to move the passive link, the user provides the necessary torque / force.

[0069] Usually, if Figure 3AAs shown, the system includes a first link 302A (e.g., a proximal link) having a first end and a second end and a second link 304A (e.g., a distal link) having a first end and a second end. A joint assembly 303A connects the second end of the first link 302A to the first end of the second link 304A so that the second link 304A can move relative to the first link 302A. It is known to use a prismatic joint or a swivel joint, two couple two links in the system, so it will not be described in detail here.

[0070] The joint assembly 303A includes a dual brake assembly 305A. The dual brake assembly 305A is coupled to the first link 302A and the second link 304A. The dual brake assembly 305A is actively controlled by a controller (such as the controller 290).

[0071] Although in this example, the dual brake assembly 305A is included in the joint assembly 303A, this is exemplary only and is not intended to be limiting. Generally, the dual brake assembly 305A includes two parts, a first part provides braking when the dual brake assembly 305A is not powered, and a second part provides braking when the dual brake assembly 305A is powered.

[0072] As mentioned above, dual brake assembly 205 is described as comprising two parts. The first part provides the first brake holding strength when physically engaged, and the second part provides the second brake holding strength when physically engaged. The second brake holding strength is different from the first brake holding strength, and in one aspect, the second brake holding strength is greater than the first brake holding strength. Similarly, each dual brake assembly described herein comprises similar two parts. In one aspect, the first part is the first brake, and the second part is the second brake. In all examples of dual brake assemblies comprising dual brake assembly 305A, the dual brake assembly reduces the relative motion between the first connecting rod and the second connecting rod coupled to the dual brake assembly.

[0073] The controller is coupled to the dual brake assembly 305A to control the state of the first brake and the second brake. In one aspect, if the system is in a fault state, the controller physically engages the first brake and physically disengages the second brake. If the system is in a clutch mode, the controller physically disengages the first brake and physically disengages the second brake. During a program, the controller physically disengages the first brake and physically engages the second brake.

[0074] In this document, when it is said that the brake is engaged or physically engaged, it means that the brake provides at least some braking. When it is said that the brake is disengaged or physically disengaged, it means that the brake does not provide braking.

[0075] FIG. 3B to FIG. 3E yes Figure 3A Schematic diagram of a possible implementation of a joint assembly 303A and a dual brake assembly 305A. Figure 3B , Figure 3C and Figure 3E is a configuration that includes an active control joint, and Figure 3D Is a configuration that includes a passive connector.

[0076] exist Figure 3B In the embodiment of the present invention, the system includes a first connecting rod 302B (e.g., a proximal connecting rod) having a first end and a second end and a second connecting rod 304B (e.g., a distal connecting rod) having a first end and a second end. The joint assembly 303B connects the second end of the first connecting rod 302B to the first end of the second connecting rod 304B so that the second connecting rod 304B can move relative to the first connecting rod 302B. The joint assembly 303B includes a joint and a double brake assembly 305B. The joint is actively controlled by a controller. The double brake assembly 305B is coupled to the first connecting rod 302B and the second connecting rod 304B. In this example, the double brake assembly 305B is included in the joint assembly 303B. However, this is only illustrative and is not intended to be limited. The double brake assembly 305B includes two parts, for example, an actuator brake 305B1 (the first brake) and a joint brake 305B2 (the second brake).

[0077] exist Figure 3B In the example of , the joint assembly 303B further includes an actuator 306B and a transmission assembly 307B, which are configured to move the second link 304B relative to the first link 302B. The output of the actuator 306B is input to the transmission assembly 307B. The output of the transmission assembly 307B moves the second link 304B.

[0078] The actuator 306B may be an electric motor, a pneumatic actuator, a hydraulic actuator, etc. The transmission assembly 307B reduces the output of the actuator 306B to an output suitable for moving the second link 304B relative to the first link 302B. When the actuator 306B is an electric motor, the transmission assembly 307B may be, for example, a harmonic drive.

[0079] exist Figure 3B In FIG. 3 , the housings of the actuator brake 305B1, the actuator 306B, the transmission assembly 307B, and the joint brake 305B2 are stationary relative to the first link 302B. The joint brake 305B2 is connected to the second link 304B, and the actuator brake 305B1 brakes the output of the actuator 306B.

[0080] During a procedure performed using the system, in one aspect, the joint brake 305B2 is physically engaged by the controller, and thus provides braking. The actuator brake 305B1 is physically disengaged, and thus does not provide braking.

[0081] In this aspect, the joint brake 305B2 is configured to provide braking on the second link 304B so that the second link 304B remains substantially stationary relative to the first link 302B in response to the reaction load on the second link 304B. Maintaining the second link 304B substantially stationary during a procedure performed using the system can minimize vibration of any device (such as an instrument (e.g., a medical instrument such as a surgical instrument)) coupled to the second end of the second link 304B. In this article, substantially stationary means that any movement of the second link relative to the first link does not cause the instrument coupled to the second link 304B to move more than a predetermined acceptable amount. In one aspect, the predetermined acceptable amount is one to three millimeters. Similarly, when the word "stationary" is used in relation to the effect of the brake on the link, it is understood that a small amount of movement of the link is acceptable as long as the small amount of movement does not cause the instrument to move more than a predetermined acceptable amount.

[0082] The braking provided by the joint brake 305B2 during the program can be as large as possible so as to limit the movement of the second link 304B in response to the reaction load, without worrying about being able to move the second link 304B in a fault situation. In one aspect, as long as no fault situation occurs, the joint brake 305B2 provides braking (e.g., physically engaged). On the other hand, the controller uses the actuator 306B to limit the movement of the second link 304B relative to the first link 302B until the actuator 306B is not enough to reduce vibration or is not important for reducing vibration, for example, when a command to move the assembly coupled to the second link 304B is issued and it is necessary to maintain a strength greater than that which the actuator 306B can provide, the controller issues a command to physically engage the joint brake 305B2 of the dual brake assembly 305B. Therefore, in this aspect, the joint brake 305B2 is not engaged until the dual brake assembly 205 is needed to control vibration.

[0083] If a fault condition occurs and if the joint brake 305B2 is physically engaged, the joint brake 305B2 is physically disengaged by the controller and thus does not brake the joint assembly 303B. Thus, in a fault condition, the joint brake 305B2 does not inhibit movement of the second link 304B relative to the first link 302B.

[0084] The actuator brake 305B1 is configured to limit the movement of the second link 304B relative to the first link 306B1 when the dual brake assembly is powered off (e.g., the system loses power) and is in a fault condition. In one aspect, the actuator brake 305B1 is a power-off brake such that when power is removed from the actuator brake 305B1, the actuator brake 3025B1 (first brake) provides braking on the joint assembly 303B to limit the movement of the second link 304B relative to the first link 302B. However, the strength of the actuator brake 305B1 is designed so that when sufficient force is applied to move the second link 304B relative to the first link 302B, the braking allows the actuator brake 305B1 to slip in an emergency. In a fault condition, the dual brake assembly 305B still provides braking, but allows the second link 304B to move relative to the first link 302B if sufficient force is applied to the second link 304B to cause the actuator brake 305B1 to slip.

[0085] To review, in this regard, during a procedure performed using the system, the joint brake 305B2 is physically engaged and the actuator brake 305B1 is physically disengaged. If during the procedure, the actuator 306B fails in the always-on state, such as a motor runaway condition of an electric motor actuator, the actuator brake 305B1 is physically engaged to offset the actuator failure. In one aspect, the controller disengages the joint brake 305B2 after a predetermined time after the controller detects the always-on fault. On the other hand, if during the procedure, the actuator 306B fails in the always-on state, such as a motor runaway condition of an electric motor actuator, the actuator brake 305B1 is physically engaged to offset the actuator failure, and the joint brake 305B2 is physically disengaged without any time delay.

[0086] Because the actuator brake 305B1 acts directly on the output of the actuator 306B, the actuator brake 305B1 can have higher backlash and lower torque relative to the joint brake 305B2 and still control any reaction load on the second link 304B. This is because the transmission assembly 307B reduces the effect of wider tolerances. For example, the transmission assembly 307B reduces the amount of backlash by the output reduction ratio of the transmission assembly 207B. For example, if the backlash is six degrees and the reduction ratio is 120:1, the backlash at the output of the transmission assembly 307B is 0.05 degrees. For example, the transmission assembly 307B increases the torque by the output reduction ratio of the transmission assembly 307B. For example, if the brake holding strength is 1 Newton meter and the reduction ratio is 120:1, the holding strength at the output of the transmission assembly 307B is 120 Newton meters.

[0087] In a computer-assisted medical system, acceptable backlash is determined by determining the amount of movement of an attached instrument due to backlash, as long as the movement is less than a predetermined acceptable amount. Any backlash that causes the instrument to move less than a predetermined acceptable amount is called low backlash. Backlash is the amount by which a joint moves when a very small load or torque is applied. Stiffness determines the amount of deflection of a joint when more load is applied. For example, an applied force F may cause the joint to deflect an amount x. If the deflection is linear with respect to force, the stiffness of the joint is k, where k = F / x. In the example of joint assembly 203, joint assembly 203 can deflect at some small angles because torque is required to overcome the inertia of entering guide manipulator 230. The higher the stiffness of dual brake assembly 205, the smaller the deflection of joint assembly 203. The smaller the deflection of joint assembly 203, the smaller the vibration amplitude at the tip of the instrument. If the torque is reversed, the total deflection is the sum of the deflection caused by backlash and the compliance (ie, the inverse of stiffness) of the dual brake assembly 205 .

[0088] On the other hand, during the procedure, the joint brake 305B2 is physically engaged and the actuator brake 305B1 is physically engaged. This has two advantages. First, with both brakes engaged, a larger reaction force on the second link 304B can be offset. Alternatively, this can allow a cheaper smaller brake to be used as the joint brake 305B2, because the joint brake 305B2 does not need to be configured to offset the maximum expected reaction torque / force alone. The second advantage is that if the actuator fails in the normally open state, the actuator brake 305B1 is already engaged. Of course, the disadvantage is that the actuator 306B cannot be used to move the second link 304B during this procedure.

[0089] exist Figure 3C In the embodiment of the present invention, the system includes a first connecting rod 302C (e.g., a proximal connecting rod) having a first end and a second end and a second connecting rod 304C (e.g., a distal connecting rod) having a first end and a second end. The joint assembly 303C connects the second end of the first connecting rod 302C to the first end of the second connecting rod 304C so that the second connecting rod 304C can move relative to the first connecting rod 302C. The joint assembly 303C includes a joint and a double brake assembly 305C. The joint is actively controlled by a controller. The double brake assembly 305C is coupled to the first connecting rod 302C and the second connecting rod 304C. In this example, the double brake assembly 305C is included in the joint assembly 303C. However, this is only illustrative and is not intended to be limited. The double brake assembly 305C includes two parts, for example, an actuator brake 305C1 (the first brake) and a joint brake 305C2 (the second brake).

[0090] exist Figure 3CIn the example of , the joint assembly 303C further includes an actuator 306C and a transmission assembly 307C, which are configured to move the second link 304C relative to the first link 302C. The output of the actuator 306C is input to the transmission assembly 307C. The output of the transmission assembly 307C moves the second link 304C.

[0091] The actuator 306C may be an electric motor, a pneumatic actuator, a hydraulic actuator, etc. The transmission assembly 307C reduces the output of the actuator 306C to an output suitable for moving the second link 304C relative to the first link 302C. When the actuator 306C is an electric motor, the transmission assembly 307C may be, for example, a harmonic drive.

[0092] exist Figure 3C 304C, the housings of the actuator brake 305C1, the actuator 306C, the transmission assembly 307C, and the joint brake 305C2 are stationary relative to the second link 304C. The joint brake 305C2 is connected to the second link 304C, and the actuator brake 305C1 brakes the output of the actuator 306C. The operation of the components of the joint assembly 303C is the same as the operation of the corresponding components of the joint assembly 303B, so it will not be repeated.

[0093] Figure 3D is a schematic diagram of the passive joint assembly 303D without the actuator. Figure 3D In the embodiment of the present invention, the system includes a first link 302D (e.g., a proximal link) having a first end and a second end and a second link 304D (e.g., a distal link) having a first end and a second end. A joint assembly 303D connects the second end of the first link 302D to the first end of the second link 304D so that the second link 304D can move relative to the first link 302D. The joint assembly 303D includes a passive joint (an actuator is not used to move the joint) and a dual brake assembly 305D. The dual brake assembly is actively controlled by a controller (such as the controller 290), while the passive joint is not controlled by the controller.

[0094] The dual brake assembly 305D is coupled to the first link 302D and the second link 304D. In this example, the dual brake assembly 305D is included in the joint assembly 303D. However, this is only illustrative and is not intended to be limiting.

[0095] The dual brake assembly 305D includes a power-off brake 305D1 (a first brake or a first portion) and a power-on brake 305D2 (a second brake or a second portion). When power is removed from the dual brake assembly 305D, the power-off brake 305D1 is physically engaged, and when power is applied to the dual brake assembly 305D, the power-off brake 305D1 is physically disengaged. When power is applied to the dual brake assembly 305D, the power-on brake 305D2 is physically engaged, and when power is removed from the dual brake assembly 305D, the power-on brake 305D2 is physically disengaged.

[0096] In this aspect, the powered brake 305D2 is configured to provide braking on the second link 304D in response to a reaction load on the second link 304D to limit movement of the second link 304D relative to the first link 302D. Maintaining the second link 304D substantially stationary can minimize vibration of any device, such as an instrument (e.g., a medical instrument such as a surgical instrument), coupled to the second end of the second link 304D during a procedure using the system.

[0097] The braking provided by the powered brake 305D2 during the procedure can be as great as possible in order to keep the second link 304D in place in response to the reaction load without having to worry about being able to move the second link 304D if a fault condition occurs. The powered brake 305D2 provides braking, such as being physically engaged, as long as a fault condition does not occur. If a fault condition occurs, the powered brake 305D2 is physically disengaged by the controller and therefore does not provide braking on the second link 204B. Therefore, when a fault occurs, the powered brake 305D2 does not inhibit the movement of the second link 304D relative to the first link 302D.

[0098] The power-off brake 305D1 is configured to limit the movement of the second link 304D relative to the first link 306D when the system is powered off, when the dual brake assembly 305D is powered off, and when a fault condition occurs in the system. The holding strength of the power-off brake 305D1 is designed so that when sufficient torque / force is applied to move the second link 304D relative to the first link 302D, the brake allows the power-off brake 305D1 to slip. Therefore, in a fault condition, the dual brake assembly 305D still provides braking, but allows the second link 304D to move relative to the first link 302D if sufficient torque / force is applied to the second link 304D to cause the power-off brake 305D1 to slip.

[0099] exist Figure 3EIn the embodiment of the present invention, the system includes a first connecting rod 302E (e.g., a proximal connecting rod) having a first end and a second end and a second connecting rod 304E (e.g., a distal connecting rod) having a first end and a second end. A joint assembly 303E connects the second end of the first connecting rod 302E to the first end of the second connecting rod 304E so that the second connecting rod 304E can move relative to the first connecting rod 302E. The joint assembly 303E includes a joint and a double brake assembly 305E. The joint is actively controlled by a controller. The double brake assembly 305E is coupled to the first connecting rod 302E and the second connecting rod 304E. In this example, the double brake assembly 305E is included in the joint assembly 303E. However, this is only illustrative and is not intended to be limited. The double brake assembly 305E includes two parts, such as a first brake 305E1 and a second brake 305E2.

[0100] exist Figure 3E In the example of , the joint assembly 303E further includes an actuator 306E and a transmission assembly 307E, which are configured to move the second link 304E relative to the first link 302E. The output of the actuator 306E is input to the transmission assembly 307E. The output of the transmission assembly 307E moves the second link 304E.

[0101] The actuator 306E may be an electric motor, a pneumatic actuator, a hydraulic actuator, etc. The transmission assembly 307E reduces the output of the actuator 306E to an output suitable for moving the second link 304E relative to the first link 302E. When the actuator 306E is an electric motor, the transmission assembly 307E may be, for example, a harmonic drive.

[0102] exist Figure 3E , the housings of the first brake 305E1, the actuator 306E, the transmission assembly 307E, and the second brake 305E2 are fixed / stationary relative to the first connecting rod 302E. Both the second brake 305E2 and the first brake 305E1 act directly on the output of the actuator 306E. The operation of the components of the joint assembly 303E is the same as the operation of the corresponding components of the joint assembly 303B, and therefore is not repeated. Specifically, even though the second brake 305E2 and the first brake 305E1 both act on the output of the actuator 306E, the second brake 305E2 has a greater holding strength (suitable for dealing with reaction loads) than the holding strength of the first brake 305E1 (the holding strength limited by the outlet torque / force required to make the brake slip).

[0103] In one aspect, each of the joint brake and the energized brake is a brake for rotating the joint, and is implemented, for example, using a stationary electromagnet. The brake rotor is attached to a flexure, which is then connected to a shaft connected to a second connecting rod. When electrical energy is applied to the electromagnetic coil, a magnetic field is generated. The magnetic force is strong enough to bend the flexure and pull the brake rotor across a very small air gap into the surface of the electromagnet. The friction connection between the surface of the electromagnet and the brake rotor provides a braking force on the shaft. Increasing the current through the electromagnet increases the holding power of the brake. When power is removed from the electromagnet, the flexure pulls the armature across the air gap and away from the surface of the electromagnet. In the case of an air gap between the electromagnet and the armature, the shaft of the joint can rotate freely without any residual resistance. Alternatively, any electromechanical energized brake can be used as long as the brake has the required brake holding strength.

[0104] In one aspect, each joint brake acts directly on its joint without an intermediate transmission assembly. This configuration has the advantage of eliminating the additional compliance of the transmission assembly. However, since the torque multiplication factor associated with the transmission assembly is lost, the joint brake is physically larger and heavier (relative to a joint brake acting through a transmission assembly), so the joint brake itself can generate the required holding strength.

[0105] In one aspect, each actuator brake and each power-off brake is implemented, for example, by using a permanent magnet that normally pulls the brake rotor toward the friction surface. The brake rotor is connected to a shaft that is connected to the second link. Friction between the friction surface and the brake rotor prevents rotation of the shaft. When power is applied to the brake, the magnetic field of the electromagnet cancels the magnetic field of the permanent magnet and the rotor is free to move. Reversing the magnetic field of the electromagnet strengthens the magnetic field, allowing the rotor to hold a greater torque than using the permanent magnet alone. Alternatively, any electromechanical power-off brake can be used, as long as the brake has the required brake holding strength. In another aspect, the brake is a spring-applied brake, similar to Figure 5A and Figure 5B Brake shown, but without variable spring force.

[0106] In one aspect, Figure 4A205 is a representative state diagram of a controller that controls each of the dual brake assemblies described above when the dual brake assemblies are implemented in the joint assembly 203 of the computer-assisted medical system 200. In this regard, the joint assembly 203 is an actively controlled joint assembly. Although these states are described as states of the controller 290, these states are also associated with the states of the dual brake assembly 205. Moreover, although these states are described with respect to the computer-assisted system, this is merely illustrative and is not intended to be limiting. The states of the dual brake assembly can be implemented in a variety of systems.

[0107] As described above, the controller 290 may also be implemented. In this example, whenever the patient side support system 210 is powered off or the dual brake assembly 205 is powered off, the first brake of the dual brake assembly 205 is physically engaged and provides braking. The brake holding strength of the first brake limits the movement of the second link 204 relative to the first link 202, but the brake holding strength allows the user to apply an exit force on the second link 204, which generates an exit torque that causes the first brake to slip, and thus the second link 204 can move. When engaged, the brake holding strength of the second brake limits the movement of the second link 204 relative to the first link 202 during the program for the reaction torque acting on the second link 204.

[0108] If the joint actuator fails in the normally open state, the controller 290 detects an actuator always active fault. In addition, a fault may occur that may shut down the power to the computer-assisted medical system, or the dual brake assembly 205 may shut down the power. In the event of an emergency or failure, it may be necessary to manually remove the instrument from the patient. In this case, the user must be able to manually move the various links in the computer-assisted medical system. If the power fails for some reason, the dual brake assembly 205 maintains the position of the second link 204 relative to the first link 202 so that the movement caused by gravity or some other force does not cause any unexpected movement. The state diagram 400A of the controller 290 illustrates each of these events.

[0109] In the first state 401 (fault / power-off state), the first brake is physically engaged and provides braking to the joint assembly 203 associated with the dual brake assembly 205. The second brake is physically disengaged and does not provide any braking to the joint assembly 203. If the computer-assisted medical system 200 loses power, the controller 290 shuts down. In the first state 401, the brake holding strength of the first brake limits the movement of the second link 204 relative to the first link 202, but the brake holding strength allows one or more users to apply an outlet force on the second link 204, which produces an outlet torque that causes the first brake to slip, so that the second link 204 can move.

[0110] When the power is turned on or a fault is cleared, the controller 290 enters the second state 402, for example, the system transitions from the first state 401 to the second state 402. In this example, the second state 402 is the default state. The default state is the state to which the system switches before use. In this example, since the first and second brakes and the actuator that can supply torque are utilized, there are three elements, each of which has two possible states - physically engaged or physically disengaged. Therefore, there are 2 3 There are eight possible states that can be selected as default states. Table 1 shows the possible states.

[0111] Table 1

[0112]

[0113] One of the eight possible default states, state D8, physically disengages all three elements. In this example, state D8 is not considered for the default state because in state D8, it is not possible to maintain the distal link in any particular position. By eliminating state D8 as the default state, there are seven possible states that can be used as default states depending on the configuration and use of the medical system. Therefore, in this regard, any of states D1 to D7 can be selected as the default state as long as the selected default state is consistent with the configuration and use of the medical system.

[0114] As an example, state D1 is selected as the default state. This is illustrative only and is not intended to be limiting. As previously mentioned, any of the first seven states in Table 1 may be selected as the default state consistent with the configuration and use of the medical system.

[0115] return Figure 4AIn the second state 402 (the default state in this example), the controller 290 configures the dual brake assembly 205 so that the first brake and the second brake are physically disengaged. Therefore, in the second state 402, the first brake and the second brake do not provide braking to the joint assembly 203. When in the second state 402, the controller 290 commands the actuator in the joint assembly 203 to limit the movement of the second link 204 relative to the first link 202 to limit the reaction torque on the second link 204. Therefore, in this respect, the second state 402 is the default state D1.

[0116] The controller 290 can transition to several different states from the second state 402. States of interest regarding the joint assembly 203 include the third state 403 (clutch state), the fourth state 404 (forward drive state), and the fifth state 405 (entering guide manipulator (EGM) move state). The controller 290 remains in the second state 402 before an event occurs, which causes the controller 290 to transition to another state, namely one of the states 401, 403, 404, 405 and 406. If a power failure event or a fault event occurs in the second state 402, the controller 290 transitions from the second state 402 to the first state 401. If the fault event is an actuator always active fault, the controller 290 does not transition to the first state 401, but instead transitions to the sixth state 406 (actuator always active state).

[0117] The sixth state 406 is Figure 4A 4 is shown in dashed lines because the sixth state 406 is optional. Figure 4B The sixth state 406 may not typically be used in normal operation because the physical engagement of the first brake invalidates the operation of the actuator. Furthermore, if, in a fault condition, the brakes and actuators lose power, it may not be possible to execute the sixth state 406 in response to the fault because the sixth state 406 assumes that power is available to the brakes and actuators.

[0118] The user may issue a clutch command indicating that the clutch is enabled. The user issues the clutch command to be able to freely move the connecting rods of the computer-assisted medical system 200. Alternatively, if it is the first time that the power is turned on (power-on event), a system assembly is usually performed, in which the connecting rods are moved to the appropriate position to allow sterile covering of all or part of the computer-assisted medical system 200. Therefore, when a clutch enable event or an assembly start event occurs, the controller 290 transitions from the second state 402 to the third state 403 (which is a clutched state in this example).

[0119] In the third state 403, the controller 290 does not change the configuration of the dual brake assembly 205, and thus the first brake and the second brake remain disengaged. The actuator of the joint assembly 203 is in a neutral state (the movement of the joint is neither assisted nor restricted by the actuator) and / or compensates for friction to allow movement of the joint in the joint assembly 203.

[0120] If a power failure event or a fault event occurs in the third state 403, the controller 290 transitions from the third state 403 to the first state 401, which is a fault / power failure state in this example. If the fault event is an actuator full-range active fault, the controller 290 does not transition to the first state 401, but transitions to the sixth state 406. If the controller 290 receives a clutch deactivation event or an assembly completion event in the third state 403, the controller 290 transitions from the third state 403 to the second state 402.

[0121] If the controller 290 receives a forward drive event in the second state 402, the controller 290 transitions from the second state 402 to a fourth state 404, which in this example is a forward drive state. The forward drive event is generated by a command generated by the controller in response to a specified condition (e.g., automatically configuring the EGM for override or automatically configuring the EGM for transmission) or in response to a user command (e.g., from voice input, gesture input, physical input received at one or more pedals, buttons, touch screens, or received at one or more master input devices at an operator console). In the fourth state 404, both the first brake and the second brake of the dual brake assembly 205 remain disengaged, and the controller 290 commands the actuator in the joint assembly 203 to follow the position trajectory.

[0122] If a power failure event or a fault event occurs in the fourth state 404, the controller 290 transitions from the fourth state 404 to the first state 401 (fault / power failure state). If the fault event is an actuator full range active fault, the controller 290 does not transition to the first state 401, but transitions to the sixth state 406. If the controller 290 receives a forward drive completion event in the fourth state 404, the controller 290 transitions from the fourth state 404 to the second state 402.

[0123] If the controller 290 receives an entry guide manipulator (EGM) movement event in the second state 402, the controller 290 transitions from the second state 402 to a fifth state 405, which in this example is an EGM movement state. The entry guide movement event is generated by a command generated by the controller in response to a specified condition (e.g., automatically configuring the EGM for overlay) or in response to a user command (e.g., input received via any appropriate technology, including input at one or more master input devices at the operator console). Several alternative configurations of the first brake and the second brake of the dual brake assembly 205 can be used in the fifth state 405. In the first alternative, the first brake is disengaged, the second brake is engaged, and the actuator command torque (torque supplied by the actuator in response to a command from the controller 290) is used to keep the second link 204 stationary (e.g., the actuator and the second brake work together to minimize movement induced by vibration of the entry guide manipulator 230). Alternatively, the first brake is disengaged, the second brake is engaged, and the actuator command torque is not used. In another alternative, both the first brake and the second brake are engaged and the actuator command torque is not used. In yet another alternative, if both the first brake and the second brake are joint brakes (e.g., neither brake is an actuator brake), both brakes are engaged and the actuator command torque is used. (If the first brake is an actuator brake, engaging the actuator brake while the actuator command torque is being used is counterproductive because the actuator brake will resist the actuator command torque rather than adding to it.)

[0124] If a power failure event or a fault event occurs in the fifth state 405, the controller 290 transitions from the fifth state 405 to the first state 401. If the fault event is an actuator full range active fault, the controller 290 does not transition to the first state 401, but transitions to the sixth state 406. If the controller 290 receives an EGM movement completion event in the fifth state 405, the controller 290 transitions from the fifth state 405 to the second state 402.

[0125] As described above, if the joint actuator fails in the fully active state, the controller 290 detects an actuator fully active fault and transitions to an optional sixth state 406. In the sixth state 406 (sometimes referred to as the actuator fully active state 606), the controller 290 engages the first brake and the second brake of the dual brake assembly 205. As previously described, the first brake brakes the actuator output, and the second brake holds the second connecting rod. If the dual brake assembly 205 is not powered off in this case, this is a fault condition, and the holding force on the joint is reduced, so that the dual brake assembly 205 can slip when the output force is applied to the second connecting rod 204. Therefore, after a predetermined time (e.g., a time sufficient to engage the first brake and stop the output of the actuator), the controller 290 transitions from the sixth state 406 to the first state 401. Similarly, if the power to the joint assembly 203 is turned off to stop the actuator, the controller 290 transitions from the sixth state 406 to the first state 401. Although not in Figure 4A , but if the actuator full range active fault is cleared, for example, the controller 290 regains control of the actuator within a predetermined time, the controller 290 transitions from the sixth state 406 back to the second state 402. If the joint is not powered, the actuator is not included in the joint, and therefore the sixth state 406 is not used by the controller.

[0126] exist Figure 4B In another embodiment shown, the sixth state 406 is eliminated and the actuator full range motion fault is handled the same as any other fault. The first brake in the dual brake assembly 205 is sized to handle the full range motion actuator, and the other states and transitions between states are similar to those described above. Figure 4A The description is the same, so it will not be repeated here, but incorporated by reference.

[0127] exist FIG. 3B to FIG. 3E In the example of , two different brakes are used to implement a dual brake assembly. FIG. 5A to FIG. 5C In the embodiment, the dual brake assembly has two parts, which have different brake holding strengths, but both parts are implemented using a single actuator brake. The dual brake assembly 505 and dual brake assembly 505A are power-off brakes so that power is applied to disengage the brake.

[0128] The dual brake assembly 505 is mounted on the actuator 502. The brake rotor 516 is rotationally keyed to the shaft 502S of the actuator 502, and the brake rotor 516 floats axially relative to the shaft 502S, so that the moving brake caliper 515M can push the brake rotor 516 toward the stationary brake caliper 515S. Alternatively, if the brake rotor 516 is also axially fixed to the shaft 502S, only the moving brake caliper 515M may have an effect on the brake rotor 516, so the stationary brake caliper 515S can be eliminated. For the same force and material, this will reduce the holding strength by half.

[0129] When the dual brake assembly 505 is de-energized, the plurality of springs 517 urge the moving caliper 515M toward the stationary caliper 515S against the brake rotor 516. The stationary caliper 515S is coupled to the housing of the actuator 502. If power is applied to the dual brake assembly 505, the electromagnet overcomes the force on the moving caliper 515M from the plurality of springs 517 and pulls the moving caliper 515M away from the brake rotor 516 so that the shaft 502S can move freely.

[0130] The holding strength of the dual brake assembly 505 is proportional to the normal force applied by the brake calipers 515M, 515S to the brake rotor 516. The normal force is provided by the plurality of springs 517, which push the mobile brake caliper 515M toward the brake rotor 516. When the dual brake assembly 505 is disengaged, the electromagnet generates a force in the direction opposite to the normal force provided by the plurality of springs 517 to pull the mobile brake caliper 515M away from the brake rotor 516. The brake holding strength is changed by changing the normal force provided by the plurality of springs 517.

[0131] In this aspect, changing the normal force provided by the plurality of springs 517 is achieved by changing the displacement offset of the plurality of springs 517. In the dual brake assembly 505, each of the plurality of springs 517 is located on a different cap in the plurality of spring caps 518. Each spring cap rotates around a pivot point 518P. The angular position of each spring cap in the plurality of spring caps 518 is controlled by a controller. The combination of the plurality of springs 517 and the plurality of spring caps 518 is an example of a variable load assembly. In this aspect, the variable load assembly is a variable load spring assembly.

[0132] The controller can change the angular position of each spring cap in the plurality of spring caps 518 about its pivot point. Changing the angular position of the spring cap will change the displacement offset on the associated spring. Figure 5A As shown, each of the plurality of spring caps 518 is in the first position, and the length of each of the plurality of springs 517 is limited to the distance between the surface of the corresponding spring cap and the surface of the moving brake caliper 515M. Figure 5B, each of the plurality of spring caps 518 is in the second position, and the length of each of the plurality of springs 517 is again limited to a different distance between the surface of the corresponding spring cap and the surface of the moving brake caliper 515M. Figure 5B The length of the spring is longer than Figure 5A In other words, each of the plurality of springs 517 has a length of Figure 5A In Figure 5B Therefore, the plurality of springs 517 are compressed more in Figure 5A In Figure 5B provides a greater normal force, and therefore Figure 5A The configuration shown is Figure 5B The configuration shown provides greater holding strength for the dual brake assembly 505 .

[0133] On the other hand, one of the plurality of spring caps 518 is in the first position and a second of the plurality of spring caps 518 is in the second position. Figure 5A The normal force and Figure 5B The normal force between the normal forces of is obtained.

[0134] An advantage of the dual brake assembly 505 is that a finer adjustment of the normal force, and therefore a finer adjustment of the holding strength, can be achieved relative to the single brake configuration of the prior art. Depending on the angular position of the multiple spring caps 518, the multiple springs 517 can have different displacements and can produce different normal forces. The spring force is generally linear with the deflection or gap change, while the force from the electromagnet is not. Therefore, compared with the electromagnetically applied brake, the spring-applied brake can be more easily configured to apply a specific force or torque, and the spring-applied brake is less prone to variations in holding strength due to the tolerance stack-up in the various components that make up the brake assembly.

[0135] The dual brake assembly 505A is equivalent to the dual brake assembly 505, except that the plurality of spring caps 518 have been replaced with a plurality of cam assemblies 518A. As each cam assembly rotates, the displacement of the springs located on the cam assembly also changes, so the brake holding strength of the dual brake assembly changes. The combination of the plurality of springs 517 and the plurality of cam assemblies 518A is another example of a variable load assembly.

[0136] Figure 6 6 is a cross-sectional view of an embodiment of a joint assembly 203 having a dual brake assembly 605. The dual brake assembly 605 includes an actuator brake 605A and a joint brake 605B. The joint assembly 203 is mounted on the first link 202 and allows the second link 204 to move relative to the first link 202.

[0137] The joint assembly 203 further includes an actuator, which is an electric motor, and a transmission assembly, which is a harmonic drive 620 . The electric motor includes motor stator windings 631 , motor rotor magnets 633 , motor bearings 637 , and a shaft 657 .

[0138] The joint assembly 203 also includes a joint absolute position sensor 619, a motor position sensor 658, and a joint bearing 601. In this aspect, the joint bearing 601 is a tapered roller bearing.

[0139] The joint brake 605B includes an electromagnetic coil 699 and a moving armature 610. A flexure 611 connects the armature 610 to a hub 612. The hub 612 is fixed to the second link 204.

[0140] The actuator brake 605A is a motor brake 605A that brakes the electric motor of the actuator including the joint assembly 203. The motor brake 605A includes an electromagnetic coil 640, a moving brake caliper 645, a stationary brake caliper 646, and a brake rotor 644. The brake rotor 644 is keyed to the motor shaft 657. The spring that pushes the moving brake caliper 645 to sandwich the brake rotor 644 between the two brake calipers when there is no power is in the Figure 6 Not visible in.

[0141] Although some of the examples described herein relate to surgical procedures or tools, or medical procedures and medical tools, the disclosed technology is applicable to medical and non-medical procedures and medical and non-medical tools. For example, the tools, systems and methods described herein can be used for non-medical purposes, including industrial uses, general robotic uses, and sensing or manipulating non-tissue artifacts. Other example applications relate to cosmetic improvements, imaging of human or animal anatomical structures, collecting data from human or animal anatomical structures, assembling or disassembling systems, and training medical or non-medical personnel. Additional example applications include the use of procedures for removing tissue from human or animal anatomical structures (without returning to human or animal anatomical structures), and the use of procedures performed on human or animal corpses. In addition, these technologies can also be used for medical treatment procedures or diagnostic procedures that include or do not include surgical aspects.

[0142] In some of the above examples, the terms "proximal" or "proximally" are generally used to describe an object or element that is closer to the manipulator arm base along a kinematic chain moving along the system or farther away from the remote center of motion (or surgical site) along a kinematic chain moving along the system. Similarly, the terms "distal" or "distally" are generally used to describe an object or element that is farther away from the manipulator arm base along a kinematic chain moving along the system or closer to the remote center of motion (or surgical site) along a kinematic chain moving along the system.

[0143] As used herein, “first”, “second”, “third”, “fourth”, etc. are adjectives used to distinguish different components or elements. Therefore, “first”, “second”, “third”, “fourth”, etc. are not intended to imply any order of components or elements.

[0144] The above description and accompanying drawings illustrating various aspects and embodiments of the present invention should not be construed as limiting - the claims define the protected invention. Various mechanical, compositional, structural, electrical and operational changes may be made without departing from the spirit and scope of the present specification and claims. In some cases, well-known circuits, structures and techniques have not been shown or described in detail to avoid obscuring the present invention.

[0145] In addition, the terms of this specification are not intended to limit the present invention. For example, spatially relative terms, such as "under ... ", "under ... ", "bottom", "above ... ", "upper", "near side", "distal side" and the like, can be used to describe the relationship between an element or feature and another element or feature as shown in the figure. These spatially relative terms, in addition to the orientation and orientation shown in the figure, are also intended to cover the different orientations (i.e. positions) and orientations (i.e. rotational arrangements) of the equipment in use or operation. For example, if the device in the accompanying drawings is turned over, the elements described as "under" or "under" other elements or features will be "above" or "on" other elements or features. Therefore, the exemplary term "under ... " can include both the orientation and orientation of the upper and lower parts. The equipment can be oriented (rotated 90 degrees or other orientations) in other ways, and the spatial relative descriptors used in this article are interpreted accordingly. Similarly, the description of the movement along and around various axes includes various specific equipment orientations and orientations.

[0146] Unless the context indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms as well. The terms "include", "comprise", "include", "contain", etc. specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups. Components described as coupled may be directly electrically or mechanically coupled, or they may be indirectly coupled via one or more intermediate components.

[0147] The various controllers described herein can be implemented by software, hardware, firmware, or any combination of the three executed on a processor. When the controller is implemented as software executed on a processor, the software is stored in a memory as computer-readable instructions, and the computer-readable instructions are executed on the processor. All or part of the memory may be located in a physical location different from the processor, as long as the processor can be coupled to the memory. The memory refers to volatile memory, non-volatile memory, or any combination of the two.

[0148] Additionally, as described herein, the functionality of the various controllers may be performed by one unit or divided between different components, each of which in turn may be implemented by any combination of hardware, software executed on a processor, and firmware. When divided between different components, the components may be centralized in one location or distributed throughout the system for distributed processing purposes. Execution of the various controllers results in methods that perform the processes described above for the various controllers.

[0149] The processor is coupled to a memory containing instructions executed by the processor. This can be implemented within the computer system, or alternatively via a connection to another computer via a modem and analog lines, or a digital interface and digital carrier lines, or via a connection using any of the protocols described above. In view of this disclosure, the instructions used in any part or all of the processes described herein can be implemented in a wide variety of computer system configurations using operating systems and computer programming languages ​​of interest to the user.

[0150] As used herein, a computer program product includes a computer-readable medium configured to store computer-readable code required for any part or all of the processes described herein, or in which computer-readable code for any part or all of those processes is stored. Some examples of computer program products are CD-ROM discs, DVD discs, flash memory, ROM cards, floppy disks, tapes, computer hard drives, servers on a network, and signals representing computer-readable program code transmitted over a network. A non-transitory tangible computer program product includes a tangible computer-readable medium configured to store computer-readable instructions for any part or all of the processes, or in which computer-readable instructions for any part or all of the processes are stored. A non-transitory tangible computer program product is a CD-ROM disc, DVD disc, flash memory, ROM card, floppy disk, tape, computer hard drive, and other physical storage media.

[0151] All examples and illustrative references are non-limiting and should not be used to limit the claims to the specific implementations and embodiments described herein and their equivalents. Any headings are used for formatting purposes only and should not be used to limit the subject matter in any way, as text under one heading may cross-reference or apply to text under one or more headings. Finally, in view of the present disclosure, specific features described with respect to one aspect or embodiment may also be applied to other disclosed aspects or embodiments of the invention even if not specifically shown in the drawings or described in the text.

Claims

1. A system comprising: a first link having a first end and a second end; a second link having a first end and a second end; a joint connected to the second end of the first link and the first end of the second link; as well as A dual brake assembly is coupled to the first link and the second link, wherein the dual brake assembly includes a first brake and a second brake, and wherein braking the dual brake assembly reduces relative motion between the first link and the second link.

2. The system of claim 1, wherein: The first brake provides a first brake holding strength when physically engaged; and The second brake provides a second brake hold strength when physically engaged, the second brake hold strength being different than the first brake hold strength.

3. The system of claim 2, wherein: the first brake is physically engaged when not powered; and The second brake is physically disengaged when not powered.

4. The system of claim 2, wherein: The first brake comprises an actuator brake; and The second brake comprises a joint brake. 5 . The system of claim 1 , wherein if the system is in a power-off state, the first brake is not powered and is physically engaged, and the second brake is not powered and is physically disengaged.

6. The system of any one of claims 1 to 5, further comprising a controller, wherein if the system is in a fault state, the controller physically engages the first brake and physically disengages the second brake.

7. The system of any one of claims 1 to 5, further comprising a controller, wherein if the system is in a clutch mode, the controller physically disengages the first brake and physically disengages the second brake.

8. The system of any one of claims 1 to 5, further comprising a controller, wherein during a procedure, the controller physically disengages the first brake and physically engages the second brake.

9. The system according to any one of claims 1 to 5, further comprising: an actuator coupled to the joint, wherein actuation of the actuator causes the joint to move the second link relative to the first link; as well as A controller is configured to physically engage the first brake and physically engage the second brake to restrict movement of the second link relative to the first link when the actuator fails in a state configured to move the second link relative to the first link.

10. The system of any one of claims 1 to 5, wherein the first brake and the second brake comprise a single brake.

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