Force perception mechanism for a physical laparoscope simulation model.

Abstract

A simulated training model having a force perception mechanism for identifying and notifying a user when the amount of force being applied to the model exceeds a predetermined amount. The force perception mechanism has two states that are used to identify when the amount of force being applied to the model exceeds a predetermined amount. In a first state, one or more portions of the simulated training model are removably connected to one another, such as a body to a base and / or a post to a body. A second state corresponds to when one or more of the portions of the simulated training model become disconnected from one another. When a transition occurs between the first state and the second state, the surgical training model notifies a user that the force being applied to one or more of the portions of the simulated training model exceeds a predetermined amount.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 297,392, entitled “Force Perception Mechanism for Physical Laparoscopic Simulation Models,” filed January 7, 2022, the entirety of which is incorporated herein by reference.

[0002] This application relates generally to surgical training systems, and more specifically to a force perception mechanism for a physical laparoscopic simulation phantom. [Background technology]

[0003] Various problems arise when a user (e.g., a surgeon) performs laparoscopic surgery relying on the use of laparoscopic instruments to indirectly manipulate tissue. These laparoscopic instruments have various characteristics (e.g., force artifacts) that may prevent the user from receiving certain forms of feedback (e.g., tactile sensations) that may allow the user to sense how much force is being applied to the tissue during a surgical procedure. That is, the amount of force being applied by the user onto the laparoscopic instrument may not directly correspond to the amount of force being applied by the laparoscopic instrument to the tissue. If too much force is applied to the tissue during the course of a surgical procedure, the excessive force may cause trauma to the tissue. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Patent Application Serial No. 13 / 248,449 [Patent Document 2] U.S. Patent Application Serial No. 15 / 895,707 Summary of the Invention [Problem to be solved by the invention]

[0005] That is, there is a need for a surgical training system that provides training for a user to accurately estimate the amount of force being applied to tissue relative to the force being applied by the user to a laparoscopic instrument. Furthermore, a surgical training system for training the application of forces can be implemented without the use of electronic devices (e.g., sensors and digital displays). [Means for solving the problem]

[0006] According to various embodiments, a surgical training model is described herein. The model has a force sensing mechanism having a first state and a second state. In the first state, the force sensing mechanism is at least partially attached to the model. In the second state, the force sensing mechanism is detached from the model. The transition between the first and second states is used to notify a user when an amount of force being applied to the model exceeds a predetermined amount.

[0007] According to various embodiments, another surgical training model for developing and practicing skills associated with laparoscopic surgical procedures is described. The model has a post and a force sensing mechanism. The force sensing mechanism corresponds to a peg and a body of the model. When in a first state, the peg is connected to the body. In a second state, the peg is disconnected from the body. The transition from the first state to the second state is used to notify a user when the amount of force being applied to the model (on the post or any portion of the body) exceeds a predetermined amount.

[0008] According to various embodiments, another surgical training model is described. The model has a base and a body. The body (or at least a portion of the body) is removably attached to the base at predetermined locations. The model is made for two different states. While in the first state, the body is attached to the base at predetermined locations. In the second state, the body (or at least a portion of the body) is detached from the base at at least one of the predetermined locations. The transition between the first and second states notifies a user that a force being applied to the model exceeds a predetermined amount.

[0009] According to various embodiments, another surgical training model is described. The model has a base, a post, and one or more flaps. The flaps are connected to the post on one end and removably connected to the base on an opposite end. In a first state of the model, the one or more flaps are connected to the base at predetermined locations. In a second state of the model, at least one of the flaps is disconnected from the base. The transition from the first state to the second state notifies a user when the amount of force being applied to the post exceeds a predetermined amount.

[0010] According to various embodiments, another surgical model is described. The surgical model has a base, a post, and at least one indicator on the post. In the model in a first state, the at least one indicator is in a stationary position relative to the base and the post. In the model in a second state, the at least one indicator is moved away from the stationary position a predetermined distance away. The transition from the first state to the second state notifies a user when an amount of force being applied to the post exceeds a predetermined amount.

[0011] According to various embodiments, another surgical model is described. The surgical model has a base, a post removably connected to the base, and a strip connecting the same between the base and the post. With the model in a first state, the post rests on the base. With the model in a second state, the post is detached from the base and pulled a predetermined distance above the base. The transition from the first state to the second state notifies a user when the amount of force being applied to the post exceeds a predetermined amount.

[0012] According to various embodiments, another surgical model is described. The surgical model has a base with pegs at predetermined locations and a post with one or more holes at predetermined locations. In a first state of the model, the one or more holes are removably connected to the pegs at the predetermined locations. In a second state, one or more of the holes are disconnected from their respective pegs. The transition from the first state to the second state notifies a user when the amount of force being applied to the simulated surgical model exceeds a predetermined amount.

[0013] According to various embodiments, another surgical training model is described. The surgical training model has a force sensing mechanism associated with a post of the model. The force sensing mechanism has a first and a second state. In the first state, the force sensing mechanism is hidden from a user. In the second state, the force sensing mechanism is made visible to the user. The transition from the first state to the second state notifies the user when an amount of force being applied to the post exceeds a predetermined amount.

[0014] According to various embodiments, another surgical model is described. The model has a base and a post removably connected to the base. While in a first state, the model has the post removably connected to the base at a predetermined location. In a second state, the post becomes detached from the base. The transition from the first state to the second state notifies a user when the amount of force being applied to the post exceeds a predetermined amount.

[0015] Various embodiments identify another force sensing mechanism. The force sensing mechanism has a first and a second state. In the first state, a portion of the model is removably connected to a different portion of the same model. In the second state, the portion of the model is decoupled from the different portion of the same model. The transition from the first state to the second state notifies the user when the amount of force being applied to the model exceeds a predetermined amount.

[0016] According to various embodiments, another surgical training model is described. The model has a force sensing mechanism associated with a post of the model. The force sensing mechanism also has a first and a second state. In the first state, the force sensing mechanism is hidden from a user's view. In the second state, the force sensing mechanism is made visible to the user. The transition from the first state to the second state notifies the user when the amount of force being applied to the post exceeds a predetermined amount.

[0017] According to various embodiments, another force perception mechanism is described. The force perception mechanism has an indicator associated with a portion of the model. While in a first state, the indicator is hidden from the user's view. In a second state, the indicator is made visible to the user. The transition from the first state to the second state notifies the user when the amount of force being applied to the post exceeds a predetermined amount.

[0018] The present invention can be understood by reference to the following description in conjunction with the accompanying drawings, in which reference numerals designate like parts throughout the drawings. [Brief description of the drawings]

[0019] [Figure 1A] FIG. 1 illustrates an exemplary surgical training model including a body, a base, a post, and a force sensing mechanism. [Figure 1B] FIG. 1 illustrates an exemplary surgical training model including a body, a base, a post, and a force sensing mechanism. [Diagram 2] 1A-1C illustrate exemplary openings associated with the body of a surgical training model. [Diagram 3]FIG. 1 illustrates an exemplary embodiment of a force sensing mechanism. [Figure 4A] 1A-1C show an exemplary embodiment of a surgical training model interfacing a post with a body. [Figure 4B] 1A-1C show an exemplary embodiment of a surgical training model interfacing a post with a body. [Figure 4C] 1A-1C show an exemplary embodiment of a surgical training model interfacing a post with a body. [Figure 5A] 13A-13C show an exemplary embodiment of a post connected / attached to a body. [Figure 5B] 13A-13C show an exemplary embodiment of a post connected / attached to a body. [Figure 6] 13A-13C illustrate exemplary user interactions with posts of a surgical training model. [Figure 7] FIG. 1 illustrates an exemplary embodiment of a body that may interface with a post. [Figure 8A] 1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism using two or more pegs. [Figure 8B] 1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism using two or more pegs. [Figure 9A] 1A-1C illustrate an exemplary embodiment of a surgical training model having a force sensing mechanism using tethers. [Figure 9B] 1A-1C illustrate an exemplary embodiment of a surgical training model having a force sensing mechanism using tethers. [Figure 10] 1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism that releasably connects a portion of the body with a slot-shaped opening in the base. [Figure 11A] 1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism using a combination of tethers and pegs. [Figure 11B] 1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism using a combination of tethers and pegs. [Figure 11C]1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism using a combination of tethers and pegs. [Figure 12A] 1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism using a tether with an indicator. [Figure 12B] 1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism using a tether with an indicator. [Figure 13A] 13A-13C show an exemplary embodiment of a surgical training model having a force sensing mechanism using rings or washers associated with posts. [Figure 13B] 13A-13C show an exemplary embodiment of a surgical training model having a force sensing mechanism using rings or washers associated with posts. [Figure 14] 1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism using multiple strips associated with posts. [Figure 15A] 1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism using one or more flaps associated with posts connected to pegs associated with a base. [Figure 15B] 1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism using one or more flaps associated with posts connected to pegs associated with a base. [Figure 16A] 1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism that uses an attachment or platform associated with the post to connect the post with a base. [Figure 16B] 1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism that uses an attachment or platform associated with the post to connect the post with a base. [Figure 17] 1A-1C show an exemplary embodiment of a surgical training model having a force sensing mechanism using a protrusion from a portion of a post. [Figure 18] 1 illustrates an exemplary embodiment of a laparoscopic trainer. [Figure 19] 1A-1C illustrate an exemplary performance of a laparoscopic training task using an embodiment of a surgical training model described herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] In accordance with various embodiments, different surgical training systems are illustrated and described below. The surgical training phantom can be used to train various skills associated with a surgical procedure. In various embodiments, the surgical training system can incorporate a force perception mechanism. Although there are several ways to implement the force perception mechanism with the surgical training phantom, each of the force perception mechanisms described in this application is configured to provide a way to indicate when a user is applying a force (e.g., through the use of laparoscopic instruments) greater than a predefined threshold while performing a simulated surgical task on the surgical training phantom. The predefined threshold associated with the force perception mechanism can be customized to correspond to a force threshold at which tissue trauma is believed to occur during an actual laparoscopic procedure. Furthermore, the surgical training system (through the force perception mechanism) is designed to notify the user when excessive force is detected without the use of any electronics (e.g., sensors).

[0021] In various embodiments, the force sensing mechanism is provided by adding and / or modifying the surgical training model with additional components that enable it to determine the amount of force. The exemplary surgical training model 100 (as shown in FIG. 1A ) is comprised of at least a body 110, a base 120, and a post 130, although other embodiments may include more or less components. With the force sensing mechanism 140 (integrated through pegs) provided and / or integrated into the surgical training model 100, a user can monitor and be notified when he or she exerts too much force during the course of a laparoscopic training task using the surgical training model 100. Furthermore, the monitoring and notification regarding the amount of force is performed without the use of electronic devices such as sensors.

[0022] The force sensing mechanism 140 is designed to configure each part of the surgical training model 100 to respond to the force being applied by the user while the user is performing a laparoscopic training task. Before the start of a laparoscopic training task, the surgical training model 100 is provided in an initial rest state. When the user applies a force to the surgical training model 100 while performing a laparoscopic training task, the surgical training model 100 transitions to an intermediate state where each part of the surgical training model 100 responds and reacts to the force, causing the parts to move, extend, and / or disconnect from each other part of the surgical training model 100. However, when an excessive amount of force is applied to the surgical training model 100 by the user, the change applied to the surgical training model 100 transitions the surgical training model 100 to a deformed state. In various embodiments, the deformed state can render the surgical training model 100 inoperable for further use in relation to a laparoscopic training task until the surgical training model 100 is reconfigured. Thus, the deformed state is used as one of the ways to inform the user that an excessive amount of force has been used while performing a laparoscopic training task.

[0023] As described herein, laparoscopic training tasks are tasks that can be performed using the surgical training model 100 to develop and practice skills associated with a laparoscopic surgical procedure. Generally, laparoscopic training tasks are designed to practice one or more different stages or skills associated with a laparoscopic surgical procedure. In an exemplary laparoscopic training task, a user uses or is instructed to use both hands to control a limb 115 (with a surgical device in one hand) and to control a post 130 (with a different surgical device in the other hand) associated with the surgical training model 100 (see FIG. 1A or FIG. 19 ). As described herein, in various embodiments, limb 115 refers to a portion of the body 110.

[0024] Using both limb 115 and post 130, the user is guided to manipulate or manipulate post 130 through an opening associated with limb 115, or vice versa. Figure 19 illustrates an exemplary performance of this laparoscopic training task, showing two different surgical devices (e.g., graspers) for controlling and manipulating limb 115 and post 130 as described above.

[0025] Without the force sensing mechanism 140, a user will generally not be aware of the amount of force being applied while using different laparoscopic surgical devices on the surgical training model 110 because the amount of force a user applies to the proximal end of a laparoscopic device will not be accurately translated into the force being applied by the tip (i.e., the end that interacts with tissue) of this same device. Excessive force applied to a tissue site during an actual surgical (e.g., laparoscopic) procedure may cause trauma and / or damage to the site. Therefore, it is important that users are trained and / or that users learn to learn the relationship between the amount of force they are applying to a laparoscopic device and the corresponding force at the other end of the laparoscopic device being used to prevent the use of excessive force.

[0026] In various embodiments, the surgical training model 100 is designed to be reset by a user to return the surgical training model 100 from a deformed state to an initial state and / or an intermediate state. By resetting the state of the surgical training model 100 (and the force sensing mechanism 140 embodied therein), a user can repeatedly retry a laparoscopic training task using the same surgical training model 100. This "reset" feature is possible due to the reversibility of the components associated with the surgical training model 100 and the force sensing mechanism 140 and the manner in which these components interact with each other.

[0027] In various embodiments, modifications are made to each part of the surgical training model 100 (e.g., the body 110, the base 120, the post 130) to provide the force sensing mechanism 140. In various embodiments, such modifications can include additional components or structures (e.g., pegs, tethers, flaps, platforms, or combinations thereof) that are either attached to each part of the surgical training model 100 or manufactured together with the surgical training model 100 as one monolithic structure. The modifications can include changing aspects of existing features of the surgical training model 100 to interface with the additional structures. For example, the body of the surgical training model 100 can include openings that can be configured to interface with pegs (see FIG. 1B), and the post 130 can include protrusions or markings that can be used to determine the amount of force being exerted thereon. In another example, the base 120 can include slots here that allow for the additional structures of the force sensing mechanism 140 to be removably attached.

[0028] In various embodiments, the location of the additional structures (e.g., pegs, tethers, flaps, platforms, or combinations thereof) can vary. For example, the additional structures can be attached near the center of the surgical training model 100 (e.g., near the post 130), some structures can be attached to the body 110, some structures can be attached only to the post 130, and some can be attached to both.

[0029] When a user interacts with the surgical training model 100, e.g., when performing a laparoscopic training task, portions of the surgical training model 100 can be altered. For example, user interaction with one of the limbs 115 of the body 110 can cause a portion of the body 110 (e.g., limb 115) to extend. These interactions with the surgical training model 100 change the state of the surgical training model 100 between an initial state to an intermediate state, and potentially to a deformed state.

[0030] In the initial state, no force is applied to the surgical training model 100, and therefore the various components of the surgical training model 100 are in a stationary state. In this initial state, the additional structures and / or other parts of the surgical training model 100 (e.g., the body 110, the base 120, the post 130) are connected and / or fixed in place.

[0031] In the intermediate state, some force is applied to each portion of the surgical training model 100. Despite this force, the additional structures remain in contact / connection with the respective components of the surgical training model 100. While in the intermediate state, the user applied force is considered appropriate.

[0032] Finally, the deformation state corresponds to when one or more of the components of the surgical training model 100 associated with the force sensing mechanism are separated / detached from the respective additional structure or move in another predetermined manner. Upon occurrence of the deformation state, the force sensing mechanism 140 has identified that excessive force has been used. Furthermore, the deformation state is used as a form of notification to the user that the user has used an excessive amount of force corresponding to failure of a laparoscopic training task.

[0033] In various embodiments, the connections between the additional structures associated with the force sensing mechanism 140 (e.g., pegs, tethers, flaps, platforms, or any combination thereof) and components of the surgical training model 100 use frictional forces to characterize the user-applied force and identify when too much force is being used. The frictional force acts as an opposing / counterforce to the force the user applies to a portion of the surgical training model 100. However, if the amount of force being applied to the surgical training model 100 is greater than the frictional force present, the user-applied force will cause the surgical training model 100 to change state.

[0034] In various embodiments, the frictional forces present within the surgical training model 100 can be customized. The type of material used to construct the surgical training model 100 can affect the elasticity (i.e., extensibility) of the model, which affects, for example, how much of a user-applied force the surgical training model 100 can "absorb." Materials can have different surface roughnesses that can increase or decrease the frictional forces present between two moving surfaces. Other factors that can affect the frictional forces include, but are not limited to, the relative size / cross-sectional area of ​​the additional structures (e.g., pegs, tethers, flaps, platforms, or any combination thereof) compared to the portions of the surgical training model 100 that interact with the additional structures (e.g., openings in the body, slots in the base). Furthermore, the size and shape of the additional structures can also affect the amount of frictional forces.

[0035] When the user applies force to the surgical training model 100, each portion of the user-applied force will be "absorbed" while the remainder will be transferred towards the location on the surgical training model 100 where the additional structure is located. The frictional force present at the location where the additional structure is located will oppose the user-applied force (keeping the surgical training model in a neutral state). At some point in time, the amount of force acting on the surgical training model will be greater than the frictional force present at one or more different locations where the additional structure is located. When this point occurs, each portion of the surgical training model will become detached (e.g., pulled out) from the additional structure (e.g., peg, tether). That is, to identify the occurrence of excessive user-applied force, the force sensing mechanism 140 will signal the user that excessive force has been detected using the occurrence of disconnection of the surgical training model 100 from the additional structure.

[0036] In various embodiments, the disconnection of each portion of the surgical training model 100 from the additional structure changes that portion (or all) of the surgical training model 100 to a deformed state. In various embodiments, the deformed state corresponds to a change in the surgical training model 100 that is used to identify and notify the user that excessive force has been detected. In various embodiments, the deformed state can disable the surgical training model 100 to prevent further performance of a laparoscopic training task. Thus, the surgical training model 100 is configured to respond to a user-applied force by causing two or more different features (e.g., the additional structure and corresponding components or parts of the surgical training model 100) to interact with each other to enter a disconnected state. This response (e.g., disconnection) is then used to notify the user of its occurrence.

[0037] In various embodiments, other means of feedback than just visual (as described above) may be possible. For example, the surgical training model 100 may be configured to provide auditory feedback. In various embodiments, the movement and / or disconnection of an additional structure from the surgical training model 100 may generate a sound (e.g., a popping sound) that may be used to notify the user. In various embodiments, the surgical training model 100 may be configured to provide haptic feedback. For example, the surgical training model 100 may provide haptic feedback (e.g., a sudden movement, vibration, or impact) when one or more additional structures are moved or disconnected from the surgical training model.

[0038] In various embodiments, components or portions of the surgical training model 100 and / or additional structures that facilitate implementation of the force perception mechanism 140 may be interchangeable with other variations. For example, instead of the above, a body 110 with more or fewer openings or openings of different sizes may be used. Additionally, pegs of different sizes and shapes may be used. Tethers with different lengths and elasticities may be used. The above-mentioned interchangeability allows for customization of the predetermined force thresholds associated with the force perception mechanism 140 for the surgical training model 100.

[0039] 1A and 1B, these figures illustrate an exemplary surgical training model 100 having a force sensing mechanism 140. The surgical training model 100 (shown in FIG. 1A) includes a post 130, a body 110 (having one or more limbs 115), and a base 120. The force sensing mechanism 140 operates based on an interaction between an additional structure (e.g., a peg) and a modification made to the body 110 (e.g., an opening for receiving one end of the peg).

[0040] An initial configuration for the surgical training dummies 100 (corresponding to an initial state) has each of the pegs inserted through a respective opening in the body 110 (see FIG. 1A ). It should be noted that the arrangement and number of pegs and / or bodies 110 shown in FIG. 1A can vary. In various embodiments, having pegs and openings in various locations allows the surgical training dummies 100 to be configured to focus on detecting forces at specific portions thereof. In various embodiments, having more or fewer pegs and openings may affect how user-applied forces result in a response, thereby affecting the predetermined force threshold for the overall surgical training dummies 100.

[0041] In the connected state, the arrangement between the body 110 of the surgical training model 100 and the pegs corresponds to an initial state in which the body 110 of the surgical training model 100 is removably connected to the pegs. The connection with the pegs temporarily secures the body 110 of the surgical training model 100 to the base 120 by an interference fit until a user-applied force causes at least a portion of the body 110 to sever from one or more pegs.

[0042] The interaction (e.g., connection) between the openings in the body 110 and the pegs is used to detect user-applied forces applied to the surgical training model 100 (e.g., limbs), especially when an excessive amount of force is applied by the user. When the user interacts with the body 110 (e.g., limbs), a portion of the force applied to the body 110 can be transferred towards the pegs, resulting or resulting in the disconnection of the body 110 from the pegs. Depending on the material of the body 110 (e.g., elasticity), a portion of the force can be "absorbed" by the stretching of the body 110. However, at any point, the material may not be able to "absorb" all of the user-applied force. At this point, the user-applied force will be transferred towards the portion of the body 110 that is connected to the pegs.

[0043] As discussed above, the resulting frictional force of the interference fit between the opening in the body 110 and the peg is configured to exist as a counter force to a user-applied force and to prevent the body 110 from moving off the peg and disconnecting. In various embodiments, the amount of frictional force that exists between the body 110 and the peg results from the type of connection between the two. For example, the type of connection between the body 110 and the peg can be an interference fit type when the cross-sectional area of ​​the peg is the same as or larger than the cross-sectional area of ​​the opening in the body 110. The amount of frictional force in an interference fit type will depend on the ratio between the cross-sectional area of ​​the opening and the cross-sectional area of ​​the peg.

[0044] However, at some point, the user may exert an amount of force greater than the frictional force (i.e., friction threshold) that exists between the body 110 and the peg, at which point the user-applied force will cause that portion of the body 110 to break away from the peg. In some embodiments, when a user-applied force on at least a portion of the surgical training model 100 (e.g., the body 110, the post 130) exceeds the frictional force between the body 110 and the peg, that portion of the body 110 can become detached from the corresponding peg. FIG. 1B illustrates an exemplary scenario in which a user-applied force applied to one of the limbs 115 causes the body 110 to become detached from one of the pegs proximate to that limb 115. When an additional force is applied to the same limb 115, the body 110 can become detached from one or more other pegs associated with it.

[0045] Severing of the body 110 from one or more of the pegs is used to notify the user that too much force has been used on at least a portion of the surgical training model 100. This notification corresponds to a scenario in which the user may have caused trauma to the tissue during surgery based on the amount of force applied during an actual surgical procedure.

[0046] In various embodiments, the disconnection of the body 110 from one or more of the pegs can be a visual notification to a user that excessive force has been detected. Additionally, the disconnection of the body 110 from one or more of the pegs can transition the surgical training model 100 to a deformed state that can be used to notify a user that excessive force has been applied to a portion of the surgical training model 100. In particular, the deformed state can render some or all of the surgical training model 100 inoperable, thereby preventing a user from continuing with a laparoscopic training task. In some embodiments, the disconnection of the body 110 from one or more of the pegs can include other tactile and / or audible indicators that can also be used to notify a user that excessive force has been detected.

[0047] In various embodiments, a predetermined force threshold representing the amount of force a user can exert during a surgical procedure before potentially causing tissue trauma or damage can correspond to a frictional force present between the body 110 and the pegs. Thus, the predetermined force threshold can be customized by controlling how much frictional force exists between the body 110 and the pegs. This customization allows the surgical training model 100 to be adapted for different surgical procedures and / or applicable to different types of tissue where different forces may be acceptable without causing tissue trauma.

[0048] In various embodiments, the force sensing mechanism 140 is customizable, in which case the user can customize the amount of frictional force that exists between the body 110 and the peg. For example, the peg can be made interchangeable with other variations (e.g., different sizes, shapes) of pegs, which allows for different interference fits that would correspond to different amounts of force required to sever the body 110 from the peg. Changing the size of the peg can affect its connection (or fit) with the opening in the body 110, which affects the frictional force that exists.

[0049] In various embodiments, different bodies 110 having different elastic moduli can be substituted. The elasticity affects how much of a user-applied force can be "absorbed" before being transmitted towards the peg. Thus, it may take a different amount of user-applied force to sever the body 110 from the peg.

[0050] According to various embodiments, the surgical training model 100 is configured to be "reconfigurable" to return to an initial state at any point in time. According to at least the embodiment illustrated in Figures 1A and 1B, "reconfiguration" is performed by inserting cut portions of the body 110 back into the corresponding pegs. This allows a user to repeat a laparoscopic task and reuse the same surgical training model 100.

[0051] When using the exemplary surgical training model 100 shown in FIG. 1A, the surgical training model 100 can be housed in a laparoscopic / surgical trainer 1800 (discussed below in FIG. 18) that can be configured to simulate a laparoscopic condition. Such an embodiment in which the surgical training model 100 is housed in the surgical trainer 1800 can be seen in FIG. 19. In some embodiments, the surgical training model 100 can be placed in a body cavity 1805 (e.g., on a removable tray) of the laparoscopic trainer 1800. In some embodiments, the surgical training model 100 can be removably attached to the bottom of the laparoscopic trainer 1800 through the base 120 of the surgical training model 100, for example, through the use of hook-and-loop fasteners to secure that portion of the surgical training model 100 and prevent movement during laparoscopic training tasks.

[0052] In some embodiments, the body 110 of the surgical training model 100 is separate from the base 120. Since the body 110 rests substantially on the base 120, any "stickiness" between the base 120 and the body 110 (attaching or at least partially adhering the base 120 and the body 110 to each other) may indirectly affect increasing the force required to disengage the body 110 from one or more of the pegs, increasing the overall force threshold of the force perception mechanism 140. However, in various embodiments, the pegs (connected / attached to the base) can be the primary connection points between the body 110 and the base 120 by introducing a surface texture to the base 120 that minimizes or eliminates the "stickiness" between the base 120 and the body 110. Thus, the surface texture on the base 120 ensures that the base 120 does not affect the amount of frictional force that exists between the body 110 and the pegs.

[0053] As discussed above, the force threshold can be adjusted / customized to correspond to different force thresholds to simulate the delicacy of different tissues or to simulate acceptable forces for different surgical procedures before excessive force from the user can cause tissue trauma or damage. In various embodiments, the force threshold can be adjusted in any number of different ways. For example, the force threshold can be adjusted when looking at the type of connection between the body 110 and the component used to implement the force sensing mechanism 140 relative to the diameter or cross-sectional area of ​​the opening in the body 110, adjusting the surface texture on the body 110 and / or the component implementing the force sensing mechanism which can introduce additional friction (adding additional resistance to the action of the body 110 cutting from the component implementing the force sensing mechanism), introducing draft and / or adjusting the height of the pegs, adjusting the fillet radius of the pegs, adjusting the elasticity of the body material (affecting the stretchability / deformability of the body 110 and thereby affecting the stretchability / deformability of the opening), and / or any combination of these.

[0054] By changing the diameter and / or cross-sectional area of ​​the openings and / or components implementing the force sensing mechanism 140, the type of connection (e.g., interference fit) between the body 110 and these components can be adjusted. This can provide variation to the connection between the body 110 and these components, such as introducing an amount of additional frictional force that needs to be overcome to cause the body 110 to disconnect from these components. In some embodiments, the diameter of the openings in the body 110 adapted to receive the pegs can be around 7 / 32 inches to 17 / 64 inches for a 5 / 16 inch diameter peg. Exemplary openings in the body 110 of the surgical training model 100 can be seen, for example, in FIG. 2. These openings associated with the body 110 are adapted to interface with the pegs. To change / adjust the force threshold, different bodies 110 can be interchanged to have differently designed openings (e.g., having different cross-sectional areas) that would interface differently with components (such as pegs).

[0055] In various embodiments, the portions of the surgical training model 100 that facilitate implementation of the force sensing features 140 (e.g., pegs) can be manufactured (e.g., molded) separately from the surgical training model 100 (e.g., base 120) and later attached (e.g., to the base 120). In various embodiments, these same portions (e.g., pegs) can be molded together with the surgical training model 100 (e.g., base 120) as a single monolithic structure.

[0056] 3 illustrates an exemplary embodiment of a component used to implement the force sensing mechanism 140 for the surgical training model 100. In particular, the component is a peg configured to come into contact with the body 110. The diameter of the peg may be around 5 / 16 inch, but can be adjusted in correlation with the size of the opening in the body 110 to obtain a desired force threshold and thereby create some type of interference fit connection between the peg and the body 110.

[0057] Additionally, altering the surface texture of the body 110 and / or the peg can also affect the frictional force between the body 110 and the peg. Because the surfaces between the body 110 and the peg are pressed together, the surface texture can make it more difficult or easier for the surface of the body 110 in contact with the peg to move relative to the peg. For example, if both the peg and the opening of the body 110 have rough surfaces, the relative movement between the body 110 and the peg will introduce additional friction that can increase the force required to break the body 110 from the peg. However, if both the opening of the body 110 and the peg are smooth, there may be little or no additional friction as the surfaces slide with the movement caused by the force exerted by the user. Thus, the body 110 can be more easily broken from the peg compared to an embodiment having a rough surface.

[0058] With respect to introducing draft into the peg, this occurs when the vertical portion of the peg becomes more inclined corresponding to the change in the diameter of the peg along its length. Positive draft means that the diameter of the peg decreases from the bottom of the peg to the top of the peg. Positive draft is believed to gradually reduce frictional forces as the interference fit becomes looser toward the top of the peg as the body 110 is pulled. Negative draft corresponds to the opposite scenario where frictional forces are believed to increase as the body 110 is pulled toward the top of the peg.

[0059] Such adjustments can also be used to adjust the force threshold by adjusting the distance the body 110 will need to travel along the peg before it becomes severed / separated from the peg. Changing the height / length of the peg can affect the distance the body 110 will travel, thereby affecting the area the body will contact before becoming severed. For example, it is contemplated that the height of the peg can be between .25 inches and .45 inches above the surface of the base 120. Increasing the height can require, for example, the user to maintain and / or increase the amount of force exerted on the body 110 for a longer period of time, thereby making it more difficult to severe the body 110 from the peg. Conversely, embodiments in which a shorter height is used for the peg are contemplated to make it easier to severe the body 110 from the peg due to the less amount of force required to move the body 110 to severe it from the peg. Additionally, the initial placement / positioning of the opening along the height of the peg (e.g., near the bottom versus the center of the peg) can also affect the length that the body 110 will have to travel before being detached from the peg by the force the user is exerting on the body 110 (e.g., the grasper pulling on the body 110).

[0060] Figures 4A-4C illustrate an exemplary embodiment of a surgical training model 100. In particular, Figure 4A illustrates an exemplary post 130, Figure 4B illustrates an exemplary body 110 including an opening 410 configured to receive the post 130, and Figure 4C illustrates an exemplary interface / connection between the post 130 and the body 110 of the surgical training model.

[0061] In addition to interacting with the body 110 (e.g., limbs) of the surgical training model 100, in various embodiments, a user can interact with the post 130 of the surgical training model 100 while performing a laparoscopic training task associated with the surgical training model 100. Exemplary interactions can include pulling on the post 130, redirecting the direction in which the post 130 extends from the body 110 (i.e., orthogonal or perpendicular to a plane associated with the body / base).

[0062] When a user interacts with (e.g., pulls on) the post 130, a tensile load can be applied to the body 110 through the post 130. The tensile load, when transmitted to the body 110, can contribute to the body 110 becoming disconnected / detached from one or more components positioned near the post 130 with respect to implementing the force sensing mechanism 140 for the surgical training model 100. Details regarding the post 130 used in various embodiments of the surgical training model 100 are now described below.

[0063] In one embodiment, the post 130 may include a flexible tubular structure configured to extend upwardly from the base 120 (i.e., in a direction perpendicular to a plane associated with the base 120 of the surgical training model 100). In other embodiments, the post 130 may be more rigid. In various embodiments, the post 130 may have a "stand" or "stopper" 420 positioned at its bottom (see FIG. 4A).

[0064] When the post 130 is assembled with the body 110 of the surgical training model 100, the post 130 passes through an opening 410 (see FIG. 4B) in the center of the body. The post 130 can then be pushed until the stopper 420 contacts the bottom surface of the body 110 (see FIG. 4C). Furthermore, the stopper 420 can be configured to prevent the post 130 from being completely pulled out through the opening 420 of the body 110. This prevention occurs because the stopper 420 can be configured to have a cross-sectional area that is larger than the cross-sectional area of ​​the opening 410 of the body 110. Furthermore, in various embodiments, the post 130 can be connected (by an interference fit type connection) or affixed to the body 110 near the opening 410 of the body 110 (see FIG. 5A). In some embodiments, the post 130 is connected / affixed to the body 110 using an adhesive (see FIG. 5B). An adhesive connection can allow a user to exert a greater amount of force on the post 130 without concern that the post 130 will break off from the body 110. In various embodiments, the post 130 can connect and / or interface with the base 120 in a recessed space 500. The recessed space 500 provides an area where an adhesive can be applied to adhere the post 130 to the body 110. In various embodiments, the recessed space also facilitates force distribution around the center of the body 110 (close to the post 130).

[0065] In various embodiments, when a user interacts with the post 130 (e.g., the user pulls on the post 130 with a laparoscopic instrument as shown in FIG. 6 ), a portion of the tensile load associated with the user's interaction with the post 130 can be transferred to the body 110. If the amount of tensile load the user is exerting on the post 130 is excessive, the tensile load can induce a corresponding force on the body 110 (through the connection between the post 130 and the body 110) that can be greater than a predetermined force threshold. In this manner, the tensile load from the post 130 can cause the body 110 to become decoupled from one or more components (e.g., pegs) associated with the force sensing mechanism 140 of the surgical training model 100.

[0066] Various embodiments can incorporate features to minimize any possible effects that may be caused by contact between the body 110 and the base 120. For example, as shown in Figure 7, the body 110 of the surgical training model 100 can have open spaces (or openings) that would allow pockets for the posts 130 therein to avoid coming into contact with the base 120, thereby minimizing / preventing the base 120 from influencing / affecting a predetermined force threshold between the body 110 and the component.

[0067] In various embodiments, the material that constructs the post 130 can be used to affect the force threshold with respect to a tensile load being applied to the post 130. For example, if the post 130 is made of an elastic or extensible material, a portion of the post 130 can stretch, thereby altering the force threshold for the connection between the post 130 and the body 110 by changing how the force being applied to the post 130 will be transmitted. However, at some point, the post 130 may not be able to be stretched any further, so that any additional force being applied to the post 130 by the user will now be transmitted directly to the body 110, and in some embodiments, some of this force will be used up in stretching the post 130 itself before this direct transmission causes the body 110 to break off from one or more pegs.

[0068] In contrast, a rigid or non-elastic material is better able to distribute the force being applied to the body 110. Thus, in some embodiments, a force being applied to the rigid post 130 is not believed to be absorbed by any stretching of the post 130, resulting in all of the applied force being transferred to the body 110. As a result, there is a lower force threshold between the body 110 and the peg compared to using an elastic material for the post 130.

[0069] It should be noted that materials with extreme elasticity or extreme stiffness may not be useful in implementing the surgical training model 100. For example, materials with extreme stiffness, if used for the post 130 and / or body 110, may cause the post 130 and / or body 110 (e.g., a limb) to bend and prevent the completion of a laparoscopic training task (e.g., threading the post in the center of the surgical training model 100 through an opening in a limb). In contrast, it is believed that materials with extreme elasticity may minimize the effectiveness of the force sensing mechanism 140 being implemented, as the extensibility of the body 110 may absorb a large amount of the force being applied to the body 110, affecting (e.g., stretching) the opening in the body 110 that mediates the operation of the force sensing mechanism 140.

[0070] As mentioned above, based on the material used for the body 110, there may be a "stickiness" between the body 110 and the base 120 of the surgical training model 100, which may affect the function of the force-sensing mechanism 140, since the force threshold should only correspond to contact between the body 110 and the components implementing the force-sensing mechanism 140. To counteract possible stickiness from the material associated with the body 110, in some embodiments, the base 120 may be configured to add a "rough surface type" feature on the top surface of the base 120 that contacts the body 110. Other embodiments may add roughness to the bottom surface of the body 110, add an anti-adhesion coating to one or both of the body 110 and the base 120, and / or introduce additional material between the body 110 and the base 120 to prevent "stickiness" therebetween. In various embodiments, an anti-adhesion coating or layer may be attached to or integrated into one or more of the bases 120 and / or the body 110 to prevent or reduce "stickiness." In various embodiments in which the surgical training model 100 has a multi-layered body 110 , these features may be used to minimize or prevent adhesion or sticking between adjacent layers of the body 110 .

[0071] Subsequent sections of the present disclosure describe various embodiments of different variations of the force sensing mechanisms implemented with the surgical training phantom. Surgical training phantoms that utilize combinations of the different force sensing mechanisms described herein are also contemplated.

[0072] Figures 8A and 8B show another embodiment of a surgical training model 100 having a force sensing mechanism 140. Similar to the embodiment discussed above in Figures 1A and 1B, the embodiment of Figures 8A and 8B also includes a post 130, a body 110 (having one or more limbs 800), and a base 120. Although the limbs 800 associated with the body 110 are all connected, in various embodiments, the limbs 800 (extending from a central point at which the post 130 is located) can instead be separate from one another.

[0073] For each limb, a pair of openings 810, 820 are positioned on the limb 800, e.g., one at the distal end 810 of the limb (away from the post 130) and one at the proximal end 820 of the limb 800 (see FIG. 8B). For each limb 800, a component (such as a peg 830) used to implement the force sensing mechanism 140 can be connected to the proximal opening 820 at the proximal end of the limb 800. At the distal end of each of the limbs 800, a separate structure, e.g., a rod 840, configured to keep the limb attached to the base 120 can be connected to the distal opening 810 until the user decides to interact with the particular limb 800 (at which point the user can remove the limb 800 from the structure 840).

[0074] In various embodiments, the illustrated surgical training model 100 can be used to guide a user to perform a laparoscopic training task that would require the user to first detach the limb 800 from the rod 840 positioned at its distal end with one laparoscopic device. With the distal end of the limb 800 detached from the rod 840, the user can manipulate the post 130 through the now open opening at the distal end 810 of the limb 800. The user would control / manipulate the post 130 with a second laparoscopic device. With two laparoscopic devices, the user would manipulate one or both (the post 130 and / or the limb 800) to thread the post 130 through the opening at the distal end 810 of the limb 800.

[0075] Because excessive force on one or both of the limb 800 and post 130 would cause the limb 800 (and sometimes other limbs) to sever from one or more pegs 830, the user is induced to avoid applying excessive force to the limb 800 and post 130 when performing the laparoscopic training tasks described above. In various embodiments, excessive force may cause only the peg 830 associated with and / or closest to the limb 800 being manipulated to become detached from the body 110. In various embodiments, excessive force may cause one or more pegs 830 associated with and / or closest to one or more of the other limbs 800 to become detached from the body 110.

[0076] In various embodiments, the size of the pegs 830 (especially those positioned near the post 130 at the proximal end of the limb 800) may be affected by the distance those pegs 830 are positioned away from the post 130. Specifically, the closer the pegs 830 are to the post 130, the smaller the diameter / size of the pegs 830 may need to be designed to provide sufficient clearance (between the pegs 830 and the post 130 and between each other) such that a user can interact with (e.g., grasp) the pegs 830 and / or the post 130 as needed. However, smaller peg diameters may prove difficult for a user to interact with (through the proximal opening 820 of the limb 800) the pegs 830 given the size of various laparoscopic devices (e.g., graspers) in use.

[0077] In various embodiments, training can be simplified by providing separate components for implementing the force sensing mechanism 140 on different portions of the surgical training model 100. For example, various embodiments can allow a user to practice and become familiar with acting on a particular portion (e.g., one limb 800 or central post 130) without having to recognize how a force being applied to one portion of the surgical training model 100 could potentially unintentionally affect other portions of the surgical training model 100. This provides the user with the ability to focus on performing laparoscopic training tasks on a particular portion of the surgical training model 100. As with the embodiment of Figures 8A and 8B, the limbs 800 and / or pegs 830 can be configured such that a force applied to one of the limbs 800 in various embodiments does not result in an effect on the other limbs 800 and the associated pegs 830. Additionally, other embodiments may be possible in which the force sensing mechanism 140 can be attached to the post 130 and would not be affected by forces applied to one or more of the limbs 800.

[0078] In various embodiments, components associated with one portion of the surgical training model 100 (e.g., pegs 830) can be configured to be affected when forces are applied to other portions of the surgical training model 100. This can be used to complicate (i.e., make more difficult) laparoscopic training tasks. Additionally, such embodiments can more closely represent forces applied to tissues in actual surgical procedures where a procedure in one portion of a patient's body will certainly affect other portions of the patient's body.

[0079] 9A and 9B show another exemplary embodiment of a surgical training model 100 having a force sensing mechanism 140. In particular, the force sensing mechanism 140 can utilize a tether 900.

[0080] As shown in FIG. 9A, the exemplary force-sensing mechanism 140 includes a tether 900 attached at one end to the underside of the body 110 (e.g., limb). The tether 900 can be attached to the limb, for example, with an adhesive, while the opposite end of the tether is removably coupled to the base 120. In various embodiments, the releasable connection between the tether 900 and the base 120 is achieved by having a slot 910 in the base 120 through which the tether 900 is inserted. Thus, in general, the slot 910 in the base 120 will have a smaller cross-section (e.g., height and width) than the cross-section of the tether 900 to allow for an interference type connection and thus provide a certain frictional force. In doing so, the tether 900 provides the surgical training model 100 with the ability to detect the presence of an excessive amount of force when it becomes disconnected from the base 120.

[0081] In various embodiments, the predetermined force threshold associated with the force sensing mechanism 140 implemented with the tether 900 can be adjusted based on various factors. For example, the predetermined force threshold can be altered by adjusting the overall length of the tether 900 that would be inserted through the slot 910 in the base 120. In some embodiments, the tether 900 can be longer, in which case the user would be required to exert more force for a longer period of time before it can become detached from the base 120 compared to another embodiment in which the tether 900 is shorter. Additionally, the type of materials and surfaces in contact between the tether 900 and the base 120 can determine how much friction exists between the tether 900 and the base 120, as well as how much the tether 900 can stretch before it breaks from the base 120. For example, "tackiness" can add additional resistance that would increase the amount of force required to move the tether 900 and become detached from the base 120. As mentioned above, the dimensions / cross-sectional area of ​​the tether 900 and the slot 910 can be varied to affect an interference type connection between these two. The smaller the cross-sectional area of ​​the slot 910 is compared to the cross-sectional area of ​​the tether 900, the tighter the fit between the two will be, which creates a greater amount of friction that would prevent forces from causing the tether 900 to sever from the base 120.

[0082] 9A , in some embodiments, when the limb is resting on the base 120 (i.e., the surgical training model 100 is in its initial, first state), the tether 900 can rest between the base 120 and the limb. In some embodiments, if the tether 900 has a smaller dimension than the body 110 (e.g., the limb), the tether 900 can be at least partially hidden beneath the limb.

[0083] In various embodiments, the base 120 can have additional structure configured to interface / connect with the limbs (see FIG. 9A). For example, the limbs can have openings configured to interface with rods 920. In some embodiments, the rods 920 can be used to hold the limbs in a stationary position until actuated by removing the limbs from the rods 920.

[0084] In various embodiments, the tether 900 (much like the pegs described above) is configured to act as a visual indicator when an excessive amount of force is applied to the limb. In particular, a visual indicator indicating that excessive force has been detected corresponds to when the tether 900 becomes detached from the base 120. An exemplary scenario in which the tether 900 indicates that an excessive amount of force has been detected can be seen as shown in FIG. 9B, which shows the tether 900 detaching from the slot 910 in the base 920. The severing of the tether 900 can be used as an indication that an excessive amount of force has been applied to the surgical training dummies 100 that could have caused trauma to tissue during an actual surgical procedure. When the tether 900 becomes detached from the base 120, the severing transforms the surgical training dummies 100 from an initial state (the tether 900 is attached to the body 110 and the base 120) to a deformed state (portions of the tether 900 are detached from the base 120). As described above, the predetermined force threshold associated with the tether 900 can be customized to affect how much force a user can exert on the limb before the tether 900 is detached from the base 120.

[0085] In order to utilize the surgical training model 100 for further training after completion of a laparoscopic training task, the user may be guided to reconfigure the surgical training model 100 back to its initial state. Reconfiguring the surgical training model 100 can be performed by having the user reattach the tether 900 to the base 120 (by inserting the tether 900 into the slot 910) such that the tether 900 is connected to both the base 120 and the limb of the surgical training model 100.

[0086] 10 illustrates another exemplary embodiment of a surgical training model 100 having a force-sensing mechanism 140 implemented therein. In this embodiment, the surgical training model 100 includes several independent limbs 1000 that are not connected to each other or to a post 130 located in the center of the surgical training model 100. Instead, the end of the body 110 (e.g., limb 1000) closest to the post 130 can be removably connected to the base 120 through a slot-shaped opening 1010.

[0087] The slot-shaped opening 1010 is provided so that an end of the limb 1000 (the portion of the limb closest to the post 130) can be inserted therethrough to allow for a releasable connection (e.g., an interference fit connection) between the base 120 and the limb 1000. The connection between the proximal end of the limb 1000 and the base 120 provides the surgical training model 100 with a force sensing mechanism 140 that is used to identify when an excessive force is detected that corresponds to when the limb 1000 is detached from the base 120. The end of the limb 1000 that is releasably connected to the base 120 can be detached from the base 120 if a user exerts an excessive amount of force on the limb 1000 during the performance of a simulated surgical task. The detachment of the limb 1000 from the base acts as an indication that excessive force has been detected and is believed to correspond to a situation in which excessive force may have caused trauma to tissue during an actual surgical procedure.

[0088] In various embodiments, the force threshold can be modified in a manner similar to that of tether 900 described above. For example, having a cross-sectional area of ​​body 110 (e.g., limb 1000) that is greater than the cross-sectional area of ​​the slot-shaped opening 1010 in base 120 would provide more friction between body 110 and base 120. The material used for limb 1000 and / or base 120 can add features (e.g., tackiness, roughness) that would also affect the friction between body 110 and base 120 that would increase the amount of force required to cause limb 1000 to sever from base 120. The choice of material for limb 1000 would also affect how much limb 1000 can stretch before severing, and would also affect the force threshold. In addition, the length of limb 1000 that is connected through base 120 (through slot-shaped opening 1010) would also affect how much force and for how long would need to be applied before limb 1000 could sever from base 120.

[0089] 9A and 9B, the distal end of the limb 1000 may also have an opening 1020 configured to connect to a structure 1030 (e.g., a rod). The rod 1030 may be used to maintain the limb 1000 in an initial resting state while not being actuated during a laparoscopic training task, whereby the user may cause the limb 1000 to become decoupled from the previous rod 1030.

[0090] 11A-11C show another embodiment of a surgical training phantom 100 implementing a force sensing mechanism 140. In this embodiment, the force sensing mechanism 140 includes a combination of a tether 1110 and a peg 1120. As can be seen in FIG. 11B, the tether is attached at one end to the underside of the body 110 (e.g., limb 1100) and connected (through an opening 1130 in the tether 1110) to a peg 1120 attached to the base 120. In some embodiments, the limb 1100 can also have an opening 1140 at its distal end (e.g., the end furthest from the post 130) configured to connect to the same peg 1120 also on the tether 1110. The opening 1140 in the limb 1100 can provide a way to hold the limb 1100 in place with the peg 1120 until use.

[0091] With respect to the force sensing mechanism 140, each of the limbs 1100 can detect when an excessive amount of force is exerted on the limb 1100 using a combination of a tether 1110 and a peg 1120. As shown in these figures, one end of the tether 1110 is attached (e.g., attached by adhesive or constructed as a monolithic structure) to one end of the limb 1100. The other end of the tether 1110 has an opening 1130 configured to be releasably connected to a peg 1120 attached to the base 120.

[0092] 11A , the force sensing mechanism 140 (e.g., the combination of the tether 1110 and the peg 1120) will be partially hidden by the limb 1100. For example, the tether 1110 portion of the force sensing mechanism 140 may be bent / folded underneath the limb 1100, while the peg 1120 portion of the force sensing mechanism 140 will be releasably connected to the tether 1110 but will be hidden / obscured by the connection between the peg 1120 and the limb 1100 above it.

[0093] 11B illustrates an embodiment in which a user can interact with the limb 1100 and its associated force sensing mechanism 140. While in the intermediate state, the user can detach the limb 1100 from the peg 1120, thereby allowing movement of the limb 1100 for laparoscopic training tasks (e.g., manipulating an opening in the limb to thread a post therethrough). As shown in this figure, the tether 1110 is attached to the underside of the limb 1100. In various embodiments, the tether 1110 can connect to different points along the length of the limb 1100 (e.g., connecting to the center of the limb 1100). Differences in where the tether 1110 is attached to the limb 1100 can be used to affect how easily the other end of the tether 1110 detaches from the peg 1120, thereby affecting the force threshold for the force sensing mechanism 140 being implemented with the limb 1100.

[0094] 11C illustrates a scenario in which the force sensing mechanism 140 indicates that an excessive amount of force has been detected on the limb 1100. In particular, the figure illustrates that the tether 1110 has become detached from the peg 1120. In this regard, the force sensing mechanism 140 can inform the user that a laparoscopic training task involving the limb 1100 has failed due to the user exerting too much force.

[0095] In various embodiments, the action of the tether 1110 being disconnected from the peg 1120 can act as a notification to the user that an excessive amount of force has been detected on the limb 1100. In other embodiments, the action of cutting the tether 1110 can have the function of deforming / changing the entire surgical training model 100 (or at least the portion related to the force sensing mechanism 140). In the deformed state, the surgical training model 100 can be rendered inoperable. In other words, the user cannot have the function of continuing further laparoscopic training tasks with such particular limb 1100 unless the surgical training model 100 is reconfigured back to the initial first state (shown in FIG. 11A ). The step of reconfiguring the surgical training model 100 is facilitated by inserting the peg 1120 back into the opening 1140 and tether 1110 of the limb 1100.

[0096] Similar to the various embodiments discussed above, the connection between the limb 1100 and / or tether 1110 and the peg 1120 can be configured to provide different force thresholds based on the amount of friction between the tether 1110 and the peg 1120. In various embodiments, the limb 1100 and / or tether 1110 can be configured to have different force thresholds with the peg 1120. Varying the diameter and / or cross-sectional area of ​​the opening 1140 of the tether 1110 and / or varying the cross-sectional area of ​​the peg 1120 can be used to customize the amount of friction that exists between the tether 1110 and the peg 1120, and thereby customize the force threshold for the force sensing feature 140. Additionally, the type of material from which the limb 1100 and / or tether 1110 are manufactured can also affect the amount of friction between the tether 1110 and the peg 1120 and their extensibility, which can affect the force threshold of the force sensing feature 140 shown in this figure.

[0097] 12A and 12B show another embodiment of a surgical training model 100 implementing a force sensing mechanism 140. As shown in these figures, the force sensing mechanism 140 is implemented using a tether that is attached at one end to the body 110 (e.g., a limb) (e.g., attached by adhesive or cast molded as a unitary structure) and the other end is threaded through an opening in the base and allowed to extend some distance beneath the base.

[0098] In an embodiment, the tether used for the force sensing mechanism 140 can be long enough so that it is slack (above and / or below the base 120) when the surgical training model 100 is in an initial first state at the start of a laparoscopic training task. At a predetermined location along the length of the tether is an indicator 1200. For example, the indicator 1200 can be positioned where the tether meets the base during the initial first state as can be seen in FIG. 12A. In some embodiments, the indicator 1200 can be positioned directly below the base 120 and thus hidden from the user during the initial first state.

[0099] The initial location of the indicator 1200 during the initial first state is used as a visual guide corresponding to the amount of force applied to the surgical training model 100 (e.g., to an independent limb attached to such a tether). By viewing the distance the indicator 1200 travels from the initial location (e.g., at / near the base 120 seen in FIG. 12B), the user can determine whether excessive force has been applied to the surgical training model 100. Where the indicator 1200 is initially hidden from the user, exposure of the indicator 1200 above the base can be used as an indication that excessive force has been applied to the surgical training model 100.

[0100] In various embodiments, indicator 1200 can be a visual mark on the tether. In other embodiments, a physical structure such as a ring, disk, or other structure can be attached to tether 1200 and used as a visual marker to measure the amount of force being exerted on the limb based on the distance the physical structure travels from an initial location near base 120. In some embodiments, a combination of visual marks and physical structures can be used.

[0101] In some embodiments, the tether is made of an elastic material. Thus, a force applied to the tether through the limbs can stretch the tether. The elastic tether can be secured to the base 120 such that as it is stretched, it can move the indicator 1200 from an initial location to a different location (e.g., from / near the base to away / distal from the base 120, or from a location hidden beneath the base to a position above the base 120).

[0102] In other embodiments, the tether may not be extensible or anchored. When a force is applied to the tether, the portion of the tether directly beneath the base 120 can be pulled through an opening in the base 120 such that an additional portion of the tether is pulled above the base 120. As more tether is pulled above the base, the indicator 1200 will be moved from an initial location (e.g., at / near the base 120) away or distal to the base 120. In various embodiments, the tether can include a ring or stop at some point along the tether directly beneath the base 120 to prevent it from being pulled all the way above or out of the base 120.

[0103] The indicator 1200 is used to determine if an excessive amount of force has been detected. In some embodiments, any movement of the indicator 1200 can be used to signal that an excessive amount of force has been detected. In some embodiments, if the indicator 1200 remains within a predetermined amount of distance from the base 120, this can be identified as an appropriate amount of force being applied to the surgical training model 100. Thus, the tether for the force sensing mechanism 140 can be customized based on where the indicator 1200 is positioned on the tether, how far the indicator 1200 is allowed to travel from the base 120, as well as the elasticity of the tether, or any combination thereof.

[0104] When the indicator 1200 is moved from its initial location on / near the base 120, depending on the type of tether used in the force sensing mechanism 140, the user may or may not be required to manually reset the surgical training model 100 back to its initial state. In embodiments where the tether is elastic, the elastic tether can be configured to return to an unstretched state when the force applied to the surgical training model 100 is reduced / stopped. Upon returning to an unstretched state, the indicator 1200 on the tether should return to its initial location. If this embodiment of the tether is not very elastic and the indicator 1200 is pulled away from the base 120 due to an additional portion of the tether being pulled from underneath the base 120, the user may be guided to pull the tether back below the base 120 so that the indicator 1200 is in its initial location.

[0105] In some embodiments, the tether used to implement the force sensing mechanism 140 can be partially elastic and partially inelastic. In particular, the portion of the tether above the indicator 1200 can be inelastic so that any force applied to the tether does not cause this portion to stretch. However, the portion of the tether below the indicator 1200 (connected and anchored to the base 120) can be elastic. When force is applied to this embodiment of the force sensing mechanism 140, the elastic portion below the indicator 1200 will stretch due to the applied force and the indicator 1200 will move away from the base 120. When the force is released / removed from this embodiment of the force sensing mechanism 140, the elastic portion of the tether can be biased back to a non-stretched state, which in turn causes the indicator 1200 to return to its initial location / state. That is, in these embodiments, the reconfiguration of the surgical training model 100 can be performed automatically.

[0106] It should be noted that other embodiments may use other features besides the indicator 1200 described above as a visual guide to identify when excessive force is detected on the surgical training model 100. For example, instead of a marking used as the indicator 1200, other embodiments may use a physical structure such as a ring that may be attached to the tether. In other embodiments, the tether may have a protrusion that causes the tether to have a larger cross-sectional area at that particular location than the cross-sectional area of ​​its nearby or adjacent sections. In these embodiments, the physical structure or protrusion may also function to allow the user to infer how much force is being applied to the limb based on how far the physical structure or protrusion has been pulled away from the initial location / state. Furthermore, in various embodiments, the physical structure or protrusion may be configured to rest above the base 120 during the initial first state, thus allowing the surgical training model 100 to be reset back to the initial first state when the tether returns to the unstretched form (when the force being applied to the tether is released or removed). In some embodiments, the physical structure or protrusion can be configured to have a cross-sectional area that is greater than the cross-sectional area of ​​the opening in the base 120, thereby preventing the physical structure or protrusion from passing through the base 120 as the tether returns to its initial first state. In another embodiment, additional markings can be provided on the portion of the tether below the base 120. The additional markings can be color coded to reflect that an indefinite amount of force is being applied to the limb that would pull or stretch the tether base 120 above. These colors can be used to quantify whether an amount of force is acceptable or not. For example, a green marking can be shown to indicate that the force being applied is currently acceptable. However, a red marking can be shown to indicate that an excessive amount of force has been detected.

[0107] 13A and 13B show another embodiment of the surgical training model 100 implementing the force sensing mechanism 140. In this embodiment, the force sensing mechanism 140 is specifically associated with the post 130 of the surgical training model 100. In particular, a physical structure 1300 such as a ring or washer can be used as an indicator, the physical structure 1300 being affixed to a predefined location on the post 130. While in an initial first state, the physical structure 1300 can be positioned near / at the base of the surgical training model 100 (see FIG. 13A). The physical structure 1300 will be used as a visual indication associated when an excessive amount of force is applied to the post. The post 130 can be stretchable when a force is applied thereto, and would pull the indicator away from near or at the base 120 when the post 130 becomes stretched due to the applied force.

[0108] In various embodiments, the post 130 may be fixed to the base 120. When a force is applied to the post 130 (e.g., the post 130 is pulled), the post 130 will stretch (based in part on the elasticity of the material that comprises the extensible post 130). When the position of the physical structure 1300 is fixed on the post and the post stretches, the physical structure 1300 will be moved to a position relative to the base (away from the base 120) (see FIG. 13B). This change in position and the corresponding distance of the physical structure 1300 from the base 120 may be used to determine whether an excessive amount of force has been applied to the post 130; i.e., if the physical structure 1300 exceeds a predetermined distance from the base 120, this condition may be considered an excessive force detected condition. In some embodiments, the physical structure 1300 may signal that a laparoscopic training task has failed due to excessive force potentially causing trauma to the tissue being operated on (if applied during an actual surgical procedure).

[0109] To reset the surgical training model 100, the post 130 (which is at least partially resilient) can be configured to automatically return to the initial first state when the user releases the force applied to the post, allowing the indicator to return to a predetermined position at or near the body 110 and / or base 120.

[0110] It should be noted that other embodiments may use different features other than the physical structure 1300 described above. For example, instead of a ring, a visual marking (similar to that described in Figures 12A and 12B) may be used on the post 130. For example, the marking on the post 130 may be used to visually identify how much force is being applied to the post 130 based on how far the marking is pulled away from the base 120 and / or body 110.

[0111] In various embodiments, to reset the embodiment of the surgical training model 100 of Figures 13A and 13B, the posts can be configured to be biased back to the initial first state when the force applied to the posts is reduced or removed. This allows the posts to revert back from the extended state (when the force is applied to the posts) to a relaxed state (corresponding to the initial first state). In the relaxed (or unextended) state, the indicators can be configured to be positioned on or near the body 110 and / or the base.

[0112] 14 illustrates another embodiment of a surgical training model 100 implementing a force sensing mechanism 140. In particular, the force sensing mechanism 140 includes a post 130 removably connected to the base 120 and / or body 110, and a plurality of strips 1400 connected to both the post 130 and the base 120. In various embodiments, the strips 1400 can be manufactured (e.g., injection molded) as a single piece together with the post 130 and connected to the base 120 and / or body 110.

[0113] In various embodiments, the post 130 is configured to be inserted into an opening 1410 located in the base 120, the body 110, or both. The post 130 can be removably connected (e.g., interference fit) to the base 120, the body 110, or both through the opening 1410. If an excessive amount of force is applied to the post 130 (a user pulls on the post 130 with a laparoscopic instrument), the post 130 can become detached from the base 120, the body 110, or both, as shown in FIG. 14. The detachment of the post 130 from the body 110, the base 120, or both can be used as an indicator that excessive force has been detected, corresponding to potential trauma in the tissue being operated on during an actual surgical procedure. A plurality of strips 1400 are provided to secure the post 130 to the surgical training model 100 when the post 130 becomes detached from the base 120, the body 110, or both. In some embodiments, the strip 1400 may be omitted from the force-sensing mechanism 140 being implemented.

[0114] In various embodiments, the predefined force threshold associated with the post 130 can be customized. By varying factors such as the cross-sectional area or diameter of the opening 1410 in the base 120 and / or body 110, the cross-sectional area or diameter of the post 130, the materials that make up the base 120, body 110, and / or post 130, and the elastic modulus of the post 130, all of which can affect how much force is expected to be used before the post 130 becomes detached from the base 120 and / or body 110. For example, the materials that make up the post 130 and body 110 and / or base 120 can affect the amount of friction that is present when the post 130 is detached from the body 110 and / or base 120 while connected by an interference fit connection. Additionally, in embodiments in which the post 130 is elastic, the force exerted against the post 130 can be distributed along the length of the post 130 as the post 130 stretches. The distribution of force along the length of the detachable post 130 due to the stretchable properties can reduce the amount of force transmitted to the end of the post 130 connected to the base 120 and / or body 110, which increases the force threshold for the force perception mechanism 140 performed in surgical training.

[0115] 15A and 15B show additional embodiments of a surgical training model 100 having a force sensing mechanism 140. In these embodiments, the force sensing mechanism 140 is again associated with the post 130. As shown in FIG. 15A, the embodiment of the force sensing mechanism 140 can use one or more flaps 1500 attached at one end to the post 130. The other end of the flap 1500 has an opening (not shown) adapted to releasably connect with a peg 1510 attached to the base 120.

[0116] In various embodiments, the base 120 can have two or more pegs 1510. The pegs 1510 can be grouped based on the distance away from the post 130 (A or B as seen in FIG. 15A). For example, a first set of pegs (e.g., A) that are closest to the post can each be the same distance away from the post 130, while a second set of pegs (e.g., B) that are further away from the post 130 as compared to the first set of pegs can also be the same distance away. The opening of the flap 1500 is configured to connect to one of the pegs 1510. The presence of different sets of pegs 1510, one set (e.g., A) that can be closer than the other set (e.g., B), can provide different force thresholds for the force sensing mechanism 140 associated with the post 130. Specifically, the difference in distance between the first set of pegs (A) and the second set of pegs (B) provides a different force threshold for the flap 1500 based on the extension width the flap 1500 needs to extend to align the opening of the flap 1500 with the corresponding peg 1510.

[0117] As shown in the embodiment of Figures 15A and 15B, two flaps 1500 can be attached to either side of the post 130 (offset from one another by 180 degrees). A corresponding set of pegs 1510 is provided for each of the flaps 1500. In various embodiments, more than two flaps 1500 can be used with corresponding sets of pegs 1510. Various embodiments contemplate different numbers of flaps 1500 (e.g., three or more) as well as different orientations of the flaps 1500 relative to the post 130 (e.g., offset by 90 degrees).

[0118] 15B, the force-sensing mechanism 140 is implemented by attaching a flap 1500 to one of the pegs 1510 affixed to the body 110 and / or base 120. An opening in the flap 1500 is configured to engage one of the pegs 1510. When a user exerts force on the post 130 (e.g., pulling on the post with one or more laparoscopic instruments), the flap 1500 may become disengaged from one or more of the pegs 1510, thereby indicating that an excessive amount of force has been detected.

[0119] 15A, each of the flaps 1500 can engage at least two different pegs 1510, one nearer (A) and one farther (B). Depending on which peg 1510 (e.g., nearer (A) or farther (B)) the flap 1500 is connected to, a different force threshold will be associated with the flap 1500. In particular, the flap 1500 can have more slack when connected to the nearer peg (A) compared to when connected to the farther peg (B). The additional slack allows for a stronger force to be applied before excess force stretches the flap 1500 and causes it to become detached from the connected peg 1510.

[0120] The connections between the flaps 1500 and the pegs 1510 can be used as an indicator as to whether excessive force is being applied to the post 130. In some embodiments, a laparoscopic training task can instruct a user to perform a surgical procedure involving the post 130 without causing one or more of the flaps 1500 to detach from any of the pegs 1510 to which they are connected. In other embodiments, the flaps 1500 can be allowed to become detached from a predetermined number or set of pegs 1510 before indicating that excessive force has been detected.

[0121] In various embodiments, the surgical training model 100 can be configured to be inoperable if disconnection of the flap 1500 from one or more pegs 1510 occurs (corresponding to deformation of the surgical training model 100 from an initial first state to a second deformed state), however, the surgical training model 100 has the ability to reconfigure the flap 1500 back to the initial first state by reconnecting it with its respective peg 1510.

[0122] In embodiments where there are different groups of pegs 1510 (e.g., closer to the post 130 and further away from the post 130), the laparoscopic training task can take advantage of these different groupings to create different levels of difficulty. For example, the pegs 1510 further away from the post 130 can be connected to a flap 1500 that is already under some tension (i.e., in a stretched state), which requires less force to disengage the flap from the pegs 1510 further away from the post 130. In contrast, the flap 1500 connected to the pegs 1510 closer to the post 130 can have some slack. The slack associated with the flap 1500 means a lesser amount of tension, which allows the flap 1500 to absorb more force (by stretching the flap 1500) before disengaging from the pegs 1510 closer to the post 130. By relying on different tensions on the flaps 1500, the surgical training dummies may have different amounts of force required to disengage the flaps 1500 from the pegs 1510. In this manner, the surgical training dummies 100 may encourage finer or coarser force perception skills depending on whether less or more force is required from the user to disengage the flaps 1500 from the force perception mechanisms 140 that implemented the pegs 1510 during the course of a laparoscopic training task, thus allowing for gradual learning. In various embodiments, a laparoscopic training task may be made more difficult by requiring that no pegs 1510 from any group disengage from their respective flaps 1500, whereas a lower difficulty level may allow a predetermined number or subset of the pegs 1510 to disengage.

[0123] In various embodiments, the flap 1500 can be manufactured separately from the post 130. As shown, the flap 1500 can be attached to the post 130, for example, by an adhesive. However, in other embodiments, the post 130 and the flap 1500 can be manufactured as one monolithic structure.

[0124] While the embodiment described above with respect to Figures 15A and 15B involved a flap 1500 with one opening and two sets of pegs 1510, other embodiments with more than three sets of pegs 1510 or more than one opening are possible and are incorporated. Using additional sets of pegs 1510 further from the post 130 with a flap 1500 having greater or lesser tension allows for additional difficulty tiers, thereby allowing for adjustment of the force threshold for easier or more difficult simulations. It is believed that additional openings in the flap 1500 can also provide a difficulty tier function. By removably connecting multiple openings to multiple pegs 1510, it is believed that the exerciser can allow the user to disengage a predetermined number (but not all) of the openings before determining that the use of force has become excessive.

[0125] 16A and 16B show another embodiment of a surgical training model 100 implementing a force sensing mechanism 140. In this embodiment, the force sensing mechanism 140 includes a post 130 attached at its bottom to the body 110 through an attachment or platform 1600. One end of the platform 1600 is affixed (e.g., by adhesive) to the body 110. The other end of the platform 1600 has an opening 1610 configured to releasably connect (by an interference type fit) with a peg 1620 attached to the body 110. When an excessive amount of force is applied to the post 130 (by pulling on the post 130), the platform can become detached from the peg. In various embodiments, the force sensing mechanism 140 can be attached at least partially to the body 110 and the base 120 by attaching the post 130 directly to the base 120 in a similar manner.

[0126] In various embodiments, the platform 1600 at the bottom of the post 130 can be a planar structure fabricated as a single monolithic structure with the post 130 (as shown in FIGS. 16A and 16B ). The platform 1600 can have an opening 1610 on one side configured to interface with a peg 1620 positioned on the body 110. In various embodiments, the platform 1600 can be manufactured and produced separately from the post 130 and later attached to the post 130 (e.g., with an adhesive). In various embodiments, the peg 1620 can be positioned on the base 120.

[0127] As discussed above, if a user applies excessive force (e.g., pulling the post 130 in a particular direction, e.g., away from the body 110), the excessive force may cause portions of the post 130 (i.e., the attachment by the platform 1600) to break away from the peg 1620. In some embodiments, the break away of the post 130 attachment from the peg 1620 may cause the surgical training model 100 to become inoperable (i.e., cause the surgical training model 100 to progress from an initial first state to a deformed state). Additionally, the break away of the post 130 attachment from the peg 1620 may be used to indicate that excessive force has been detected during a user's performance of a laparoscopic training task using the surgical training model 100 (see FIG. 16B).

[0128] In some embodiments, the amount of force (i.e., a predetermined force threshold) required to disengage the post from the peg associated with the body 110 in one direction (e.g., toward the left in FIG. 16B ) may be different than in other directions or may not disengage at all (toward the right in FIG. 16B ). Thus, based on the location of the detachable connection between the platform 1600 and the peg 1620 and the direction in which the post 130 is pulled, the surgical training model 100 can control whether or not a force being exerted against the post 130 will activate the force perception mechanism 140.

[0129] It should be noted that the embodiments associated with components implementing the force sensing mechanism 140 with the post 130 are compatible with components implementing the force sensing mechanism 140 with the limb (or overall body 110) of the surgical training model 100. These two different parts of the surgical training model 100 can operate their force sensing mechanisms 140 independently of each other (e.g., a force on the post 130 cannot cause the body 110 to disconnect from the peg and vice versa), thereby giving the user the ability to focus on a particular part of the surgical training model 100. However, other embodiments allow the force sensing mechanism 140 of the post 130 and the force sensing mechanism 140 of the limb / body 110 to operate together (e.g., a force on the post 130 can be transferred to an adjacent component associated with the force sensing mechanism 140 associated with the limb / body 110 and vice versa). The latter embodiment is believed to increase the difficulty of various laparoscopic training tasks, as the user may need to be aware that a force applied to one portion of the surgical training model 100 affects other portions of the surgical training model 100.

[0130] FIG. 17 illustrates another embodiment of a surgical training model 100 that uses a force sensing mechanism 140. In particular, the surgical training model 100 incorporates an indicator or protrusion that corresponds to a portion of the post 130 that has a cross-section that is larger than the cross-section of the adjacent sections and larger than the opening in the base 120 through which the post 130 passes. The protrusions 1700 on the post 130 are positioned beneath the base 120 such that when a force is applied to the post 130, the protrusions 1700 can be pulled above the base 120 and exposed through the opening in the base 120. For example, as shown in FIG. 17, the post 130 can have one or more protrusions 1700 that have a large cross-sectional area compared to the adjacent sections. These protrusions 1700 associated with the post 130 are initially hidden beneath the base. When a user exerts a force on the post 130, these protrusions 1700 can be used to indicate that excessive force has been detected when one or more of the protrusions 1700 are pulled through the opening in the base 120. The exposure of the projection 1700 would visually inform the user that excessive force was detected. Additional haptic and audible feedback may also be possible as the projection 1700 is pulled through the opening. For example, haptic feedback (e.g., vibration or any sudden movement) may be associated with the projection 1700 as it is pulled through the opening. In various embodiments, haptic feedback for the projection may be associated with when the resistance / friction of the base 120 initially tries to hold the projection 1700 back and is overcome as the projection 1700 passes through the opening in the base 120. Additionally, in various embodiments, a sound (e.g., a pop) may be associated with the projection 1700 as it is pulled through the opening in the base 120. In each of these cases, haptic and / or audible feedback may provide additional ways in which the user may be notified that excessive force has been used in a laparoscopic training task.

[0131] In some embodiments, the post 130 can have a stopper (not shown) located at the distal end of the post further down the post 130 compared to the projection 1700. It is contemplated that the stopper is used to prevent the post 130 from completely disengaging from the base 120. However, in other embodiments, the stopper may be absent, which would allow a user to completely disengage the post 130 from the base 120 when excessive force is applied to the post 130. It is contemplated that such a condition could be used as an indicator that excessive force has been detected, which in turn could deform the surgical training model 100 into an inoperable state, thereby preventing further performance of a laparoscopic training task.

[0132] In various embodiments described above, the force sensing mechanism 140 provides a non-electronic way to notify the user (e.g., visually, tactilely, audibly) when excessive force or forces above a predetermined threshold are applied to the surgical training model 100. This allows the user to train, learn, and adapt the use of laparoscopic devices (e.g., graspers, dissectors) to manage the forces applied to tissue during laparoscopic procedures, thereby minimizing / preventing tissue trauma caused from such excessive forces.

[0133] To further simulate laparoscopic surgery, a laparoscopic trainer can also be used in conjunction with a surgical training model. Figure 18 illustrates an exemplary embodiment of a laparoscopic trainer. The laparoscopic trainer 1800 is designed for practicing laparoscopic or other minimally invasive surgical procedures. In particular, the laparoscopic trainer 1800 can be designed to simulate a patient's torso or abdominal area.

[0134] The laparoscopic trainer 1800 includes a body cavity 1805 that is substantially invisible to a user, for example, through a top cover 1815. The body cavity 1805 is configured to receive simulated or live tissue, or a model organ or training model. As applicable to the present disclosure, it is contemplated that the body cavity 1805 is adapted to receive any one of the surgical training models (shown in FIGS. 1-17) described above. An exemplary embodiment is shown in FIG. 19, which illustrates a body cavity 1805 housing an exemplary surgical training model 100 according to various embodiments disclosed throughout this specification. The body cavity 1805 is accessible through a tissue simulation area 1810 that is configured to be penetrated by a user with a laparoscopic device (e.g., grasper, dissector) for practicing surgical techniques or laparoscopic training tasks on a surgical training, tissue, or training model positioned in the body cavity 1805. Although the body cavity 1805 is shown accessible through the tissue simulation area 1810, other means of accessing the body cavity 1805 are possible. For example, a hand assisted access device or single site port system can be used in conjunction with laparoscopic trainer 1800 to access body cavity 1805. Further exemplary laparoscopic trainers are also described in U.S. patent application Ser. No. 13 / 248,449, filed Sep. 29, 2011, entitled "Portable Laparoscopic Trainer," and U.S. patent application Ser. No. 15 / 895,707, filed Feb. 13, 2018, entitled "Laparoscopic Training System," the entire contents of each of which are incorporated herein by reference.

[0135] The laparoscopic trainer 1800 includes a top cover 1815 connected to and spaced from a trainer base 1820 by at least one leg 1825. In some embodiments, for example as shown in FIG. 18 , the laparoscopic trainer 1800 can have multiple legs 1825. As mentioned above, in embodiments, the surgical training device 1800 can be configured to simulate a patient's torso. The top cover 1815 represents the front of the patient, and the space between the top cover 1815 and the trainer base 1820 represents the patient's interior or cavity 1805 where organs would typically reside. Thus, the laparoscopic trainer 1800 is a useful tool for teaching, practicing, and demonstrating different surgical procedures and associated instruments in a simulation of a patient undergoing a surgical procedure.

[0136] In some embodiments, surgical instruments are inserted into the body cavity 1805 through the tissue simulation area 1810. In other embodiments, surgical instruments may be inserted into pre-existing openings 1830 in the top cover 1815. In each of these embodiments, various tools and techniques may be used to penetrate the top cover 1815 to perform a simulated procedure on a simulated organ or training phantom, such as a surgical training phantom 100, positioned in the body cavity 1805 (i.e., the space between the top cover 1815 and the trainer base 1820).

[0137] In some embodiments, the trainer base 1820 can include a model receiving area 1835 or tray. The model receiving area 1835 or tray is designed for supporting or holding simulated tissue models or live tissues, as well as other practice models, such as the surgical training models described herein, on a platform. In some embodiments, the model receiving area 1835 of the trainer base 1820 can include a frame-like element for holding the model in place. To help hold the surgical training model, live organ, or practice model, such as the surgical training model 100, on the trainer base 1820, a retractable wire can be attached to the model and a clip. The clip can then be attached to the trainer base 1820 at location 1840. The retractable wire is stretched and clipped to hold the tissue model substantially underneath the tissue simulation area 1810. Other means for holding a phantom (e.g., a tissue phantom, live tissue, practice phantom, or surgical training phantom) include a patch of hook-and-loop fastening material (VELCRO®) affixed to the trainer base 1820 within the phantom receiving area 1835 so as to be removably connectable to a complementary piece of hook-and-loop fastening material (VELCRO®) affixed to the phantom.

[0138] The retention means allows the surgical training model 100 to remain attached to the bottom of the laparoscopic trainer when the user interacts with the model during any number of different laparoscopic training tasks. A variety of benefits of keeping the model attached is that the image of the model is not moved outside the field of view of any webcam or other video capture device configured to capture images of the inside of the laparoscopic trainer. Otherwise, the user may be required to readjust the model and / or the video capture device when the model 100 is inadvertently moved during a laparoscopic training task. In other embodiments, the model 100 is not attached or only loosely attached to the trainer base of the laparoscopic trainer to change the difficulty and / or operational use of the model 100 and / or its associated surgical instruments.

[0139] In some embodiments, a video display monitor 1845 may be provided that is hinged to the top cover 1815. The video display monitor 1845 is shown in a closed orientation in FIG. 18. The video monitor 1845 may be connected to various vision systems for delivering images thereto. For example, a laparoscope inserted through one of the pre-existing openings 1830 or a webcam positioned within the body cavity 1805 (used to observe the simulated procedure) may be connected to the video monitor 1845 and / or a mobile computing device (not shown) for providing images to the user. Also, recording or distribution means may be provided and integrated with the laparoscopic trainer 1800 to provide audio and visual capabilities. Means are also provided for connecting to a portable memory storage device such as a flash drive, a smart phone, a digital audio or video player, or other digital mobile device to record the training procedure and / or play pre-recorded videos on the monitor for demonstration purposes. Connection means for providing audiovisual output to a screen larger than the video monitor 1845 are also possible and may be provided for the laparoscopic trainer 1800 in various embodiments. In another embodiment, the top cover 1815 may not include a video monitor 1845, but instead may include functionality that allows for connection to a laptop computer, mobile digital device, or tablet that can view the audiovisual output of the laparoscopic trainer 1800. The connection functionality may be wired and / or wireless.

[0140] When assembled, the top cover 1815 is positioned directly above the trainer base 1820, and the legs 1825 are positioned substantially circumferentially to interconnect the top cover 1815 and the trainer base 1820. The top cover 1815 and the trainer base 1820 are of substantially the same shape and size and have substantially the same peripheral contours. The lumen 1805 is partially or totally hidden from view. In some embodiments (shown in FIG. 18 ), the legs 1825 can include openings to allow ambient light to illuminate the lumen 1805 as brightly as possible. Additionally, the openings in the legs 1825 can advantageously allow the laparoscopic trainer 1800 to be as lightweight as possible for portability reasons. In some embodiments, the top cover 1815 is detachable from the legs 1825, which in turn are detachable or foldable, such as by a hinge, with respect to the trainer base 1820. This allows the trainer 1800 in its disassembled state to have a low weight allowing for easy transport.

[0141] In accordance with various embodiments, the surgical training systems described herein include models configured to facilitate advantageous force perception training during surgical procedures. The present disclosure describes various embodiments that each include one or more variations of a body, posts, components implementing force perception mechanisms, and / or bases that provide different features for the surgical training model with which a user can interact when performing laparoscopic training tasks using the surgical training model.

[0142] According to various embodiments, the surgical training model includes a post, a body (including one or more limbs), a component implementing a force perception mechanism, a base, or any combination thereof. In various embodiments, the post can be an elongated tube. In various embodiments, one or more of the post, body, or any combination thereof can be made of an elastomeric material. In various embodiments, one or more of the post, body, or any combination thereof can be made of silicone, and in various embodiments, can be made of the same material. In various embodiments, one or more of the post, body, or any combination thereof is stretchable, flexible, and / or bendable. In various embodiments, the post has a proximal portion affixed to one or more of the body and / or base, and a distal portion bendable relative to one or more of the body and / or base. In various embodiments, the post has a proximal portion that extends away from one or more of the body and / or base, and a distal portion that curves back toward one or more of the body and / or base.

[0143] The one or more bodies, in various embodiments, include one or more limbs. In various embodiments, the body includes a central portion from which the one or more limbs extend. In various embodiments, the post has a length greater than the one or more limbs of the body. In various embodiments, the post is extensible to a length greater than the one or more limbs of the body. In various embodiments, the post, limbs, and / or any combination thereof are bendable and / or movable to contact and / or interact with one another. In various embodiments, the post has a thickness or defines a cross-section greater than a thickness or cross-section of the one or more bodies.

[0144] In various embodiments, the post is configured to connect to the body through an opening located at / near the center of the body. The post can include a stopper configured to prevent it from being pulled all the way through the body. In various embodiments, the post can include a ring, marking, or other portion having a cross-sectional area that is different (i.e., larger) than the cross-sectional area of ​​adjacent portions and allows for identification when excessive force is detected. In various embodiments, the post can be extensible. In various embodiments, the post can have a higher stiffness. In various embodiments, the post may not include a stopper, such that excessive force applied to the post (by a user pulling on the post with a laparoscopic instrument) can cause the post to break off from the base and / or body.

[0145] Various embodiments of the surgical training model are contemplated having different force sensing mechanisms. In some embodiments, the surgical training model may utilize one or more force sensing mechanisms configured to detect excessive force applied to its body or limbs. In particular, the force sensing mechanism may correspond to a peg associated with a base of the surgical training model and an interface (e.g., connection) with the body through an opening associated with the body. A force threshold associated with the connection between the structure and the body corresponds to an amount of force that can be tolerated before the body becomes detached from the structure. The force threshold is used as a means to identify an acceptable amount of force that corresponds to an amount of force that would cause trauma or damage during an actual surgical procedure.

[0146] In a state where excessive force is applied to the body (e.g., a limb), the body may become disconnected from one or more of the components implementing the force sensing mechanism. The disconnection of the body from one or more of the components implementing the force sensing mechanism can be used to transform the surgical training model from an initial first state to a deformed state that renders it inoperable, as well as to identify the state where excessive force is detected. Thus, the transformation to a secondary or deformed state while the user is performing a laparoscopic training task with the surgical training model serves as an identifier that prevents the user from further progressing in the laparoscopic training task. However, the surgical training model is configured to be reconfigurable back to the initial first state to allow the user to perform the laparoscopic training task again.

[0147] In various embodiments, the force sensing mechanism can include a tether attached to both the base and the body (e.g., the limb). In various embodiments, the tether can have a width and length smaller than that of the limb so that the strip or tether can be hidden beneath the limb in an initial first state of the surgical training model. In various embodiments, the tether can be releasably connected to the base. When the tether becomes disconnected from the base, this disconnection can be used as an indicator that too much force has been applied to the limb.

[0148] In yet another embodiment, the end of the tether may have an opening so that it can be attached to a base with a peg, and the connection between the tether and the peg has an associated force threshold that can be used to detect when excessive force is being exerted on the body / limb.

[0149] In various embodiments, the surgical training model can include one or more rods associated with the base and configured to connect to the body (e.g., limb) through an opening, the one or more rods configured to hold the body (e.g., limb) in place until a user selects to activate that particular limb.

[0150] In various embodiments, the body may include multiple limbs extending from a center of the surgical training model. However, other embodiments are contemplated in which the surgical training model includes multiple independent limbs. In some embodiments, at least one of the ends of the limbs may be attached to the base. In other embodiments, all of the limbs may be removably attached to the base.

[0151] In some embodiments, the tether can have markings that can be used to measure and identify excessive force being applied to the body / limb. The markings on the tether can initially be hidden, for example, beneath the base. As force is applied to the limb, the tether can become stretched or taut above the base. At some point, the markings can be exposed to the user, thereby indicating that excessive force has been detected on the limb.

[0152] As with the tether, similar markings can be provided on the post to measure and detect when an excessive amount of force is being applied to the post. In various embodiments, the markings can be located at a predetermined point, for example, at / near the base. When a force is applied to the post, the post can be configured to stretch, thereby moving the location of the marking away from the base. The distance that the markings move from the base can be used to determine how much force is being applied to the post and whether or not an excessive amount of force is detected.

[0153] In various embodiments, other objects such as rings or protrusions can be provided on the tether and / or post aside from the markings to measure the amount of force being applied and whether or not too much force is detected. The rings or protrusions provide a visual indicator as to how far the post or tether has been stretched and can measure and detect the amount of force being exerted on the tether or post.

[0154] In various embodiments, the post can include other features such as flaps, strips, platforms, attachments, or any combination thereof that allow it to be connected to the base and / or body. These flaps, strips, platforms, attachments, or any combination thereof can be manufactured separately and later attached to the post. In some embodiments, the flaps, strips, platforms, attachments, or any combination thereof can be manufactured with the post as one structure. In various embodiments, the post can utilize two or more of the flaps, strips, platforms, attachments, or any combination thereof together in one embodiment.

[0155] To form a connection between the post and the base / body, some embodiments may use an adhesive to connect a flap, strip, platform, attachment, or any combination thereof, of the post to the base / body. In other embodiments, the connection may be through friction with a peg associated with the base / body at an opening associated with the flap, strip, platform, attachment, or any combination thereof. Severance of one or more of the flaps, strips, platforms, attachments, or any combination thereof from the base and / or body is used as an indication when an excessive amount of force is applied to the post and detected on the post.

[0156] In various embodiments, a surgical trainer can be provided that is configured to simulate an insufflated torso or abdominal area of ​​a patient during laparoscopic surgery. The surgical trainer includes a top, a bottom, and a number of legs that form an enclosure or body cavity. A user's direct view of any model housed within the surgical trainer is obstructed, thereby requiring the user to rely on an indirect image, for example, acquired by a camera within the surgical trainer and displayed on a display screen outside the surgical trainer. The surgical trainer is configured to house one or more different models (as described above) within the body cavity. The surgical trainer is configured to allow a laparoscopic device to be placed into the surgical trainer through a top cover, for example, at a predetermined location or through an opening in the top cover.

[0157] Although the present invention has been described in certain specific embodiments, many additional modifications and variations will be apparent to those skilled in the art. Thus, it is to be understood that the present invention can be practiced otherwise than as specifically described, including various changes in size, shape, and materials, without departing from the scope and spirit of the present invention. For example, those skilled in the art should be able to use these examples to derive various different implementations that retain the primary functions of the surgical training model using the force sensing mechanism described throughout this disclosure. Although some of these embodiments utilize specific descriptions of structural and / or method-related steps, it is to be understood that such subject matter is not necessarily limited to those specifics (e.g., the functionality of a feature may be distributed differently across more than one component or may be performed using a different combination of components than those explicitly shown above). In other words, the present embodiments should be considered in all respects as illustrative and not restrictive.

[0158] The above description is also provided to enable any person skilled in the art to make and use the above-mentioned devices or systems and to perform the methods described herein, and lists the best modes of carrying out the invention contemplated by the inventor. However, various modifications may still be apparent to those skilled in the art. These modifications are contemplated to be within the disclosure of the present invention. Different embodiments or aspects of such embodiments may be shown in the various figures and described throughout the specification. However, it should be noted that although each embodiment and aspect thereof is shown or described separately, these embodiments and aspects may be combined with one or more of the other embodiments and aspects thereof, unless expressly stated otherwise. Not explicitly listing each combination is merely for ease of reading of the specification. [Explanation of symbols]

[0159] 100 surgical training model 110 Main unit 115 Limbs 120 Base 130 Posts 140 Force Perception Mechanism

Claims

1. 1. A surgical training model for developing and practicing skills associated with laparoscopic surgical procedures, comprising: a force sensing mechanism having a first state and a second state; Including, In the first state, the force sensing mechanism is at least partially attached to a phantom; In the second state, the force sensing mechanism is detached from the model; and notifying a user when the transition from the first state to the second state causes an amount of force being applied to the model to exceed a predetermined amount. Surgical training model.

2. 10. The surgical training model of claim 1, comprising a body and a post.

3. 3. The surgical training model of claim 1, wherein the force sensing mechanism includes pegs that are inserted through holes in the body of the model.

4. The surgical training model of claim 3 , wherein the pegs have an interference type fit with the holes in the body of the model.

5. the force sensing mechanism includes a tether attached between the phantom and a base; A model is seated on the base. The surgical training model according to any one of claims 1 to 4.

6. The surgical training model of claim 5 , wherein the tether is removably attached to the model and / or the base.

7. The surgical training model of claim 1 , wherein the post includes an indicator or protrusion.

8. The surgical training model of claim 7 , wherein the indicator is a visible marking made on the post.

9. 9. The surgical training model of claim 1, wherein the model is configured to be housed within an enclosure of a surgical trainer, the surgical trainer including a top, a bottom, and a plurality of legs that define the enclosure of the surgical trainer, and the surgical trainer is configured to block a direct line of sight into the enclosure.

10. 1. A surgical training model for developing and practicing skills associated with laparoscopic surgical procedures, comprising: Post and a force sensing mechanism including a peg and a body, the force sensing mechanism having a first state and a second state, in which in the first state the peg is connected to the body and in which in the second state the peg is disconnected from the body, the force sensing mechanism transitioning from the first state to the second state notifying a user when an amount of force being applied to the model through the post and / or the body exceeds a predetermined amount; A surgical training model including:

11. the body includes one or more limbs; the peg is connected to at least one of the one or more limbs through a hole positioned at a predetermined location on the one or more limbs; 11. A surgical training model according to claim 10.

12. 12. The surgical training model of claim 1, wherein the pegs are removably connected to the holes with an interference type connection that provides friction that prevents the pegs from being detached from the body up to a predetermined amount of force.

13. at least one of the one or more limbs has a plurality of holes positioned along a length of the limb; the model includes two or more pegs configured to releasably connect with two or more of the plurality of holes; the second state corresponds to at least one of the pegs being decoupled from the body. A surgical training model according to claim 11.

14. 1. A surgical training dummies for identifying when an amount of force exceeding a predetermined amount is applied during a simulated surgical procedure, comprising: With the base, a body, a portion of the body configured to be removably attached to the base at a predetermined location; Including, the model has two states, a first state in which the portion of the body is attached to a portion of the base at the predetermined location and a second state in which the portion of the body is detached from the portion of the base at the predetermined location, and a transition between the first state and the second state notifies a user that the force being applied to the model exceeds the predetermined amount. Surgical training model.

15. The surgical training model of claim 14 , wherein the body is removably attached to the base via a tether.

16. the base and the predetermined location on the base correspond to a location of a slot; the portion of the body includes a tether, the tether being attached at one end to the portion of the body and an opposite end of the tether threaded through the slot and attached beneath the base; A surgical training model according to any one of claims 1 to 15.

17. 17. The surgical training model of claim 16, wherein the tether further comprises an indicator positioned on a portion beneath the base configured to be pulled through the slot to a visible position when the amount of force exceeds the predetermined amount.

18. 18. The surgical training model of claim 1, wherein the body is removably attached to the base via a peg.

19. the base includes a peg, and the predetermined location on the base corresponds to a location of the peg; the portion of the body includes a hole configured to receive the peg. A surgical training model according to any one of claims 1 to 18.

20. 20. The surgical training model of claim 1, wherein the body is removably attached to the base via a flap.

21. the base includes a slot, and the predetermined location on the base corresponds to a location of the slot; the flap attached to the body is configured to be inserted into the slot in the base; A surgical training model according to any one of claims 1 to 20.

22. 22. The surgical training model of any one of claims 1-21, wherein the predetermined amount of force is customizable based on an amount of friction associated with a removable attachment between the portion of the body and the base at the predetermined location.

23. 1. A simulated surgical model for identifying when an amount of force exceeding a predetermined amount is applied during a simulated surgical procedure, comprising: With the base, Post and one or more flaps, the one or more flaps being connected at one end to the post and releasably connected at an opposite end to the base; Including, the one or more flaps have a first state in which the one or more flaps are connected to the base at a predetermined location and a second state in which at least one of the one or more flaps is disconnected from the base at the predetermined location, the transition from the first state to the second state notifying a user when an amount of force being applied to the post exceeds a predetermined amount. Simulated surgical model.

24. the one or more flaps have one or more holes; the one or more flaps are releasably connected to one or more pegs associated with the base through the one or more holes; 24. A surgical training model according to claim 23.

25. 1. A simulated surgical model for identifying when an amount of force exceeding a predetermined amount is applied during a simulated surgical procedure, comprising: With the base, Post and at least one indicator positioned on the post; Including, During a first state, the at least one indicator is in a resting position relative to the base and the post, and during a second state, the at least one indicator is pulled away from the resting position more than a predetermined distance, the transition from the first state to the second state notifying a user when an amount of force being applied to the post exceeds a predetermined amount. Simulated surgical model.

26. the at least one indicator is a marking on the post; the rest position being directly below the base and hidden from view of the user; the second state being a position above the base and visible by the user; 26. The simulated surgical model of claim 25.

27. the at least one indicator is a washer and the rest state is a position that causes the washer to rest on the base; the second condition being a condition in which the washer is pulled the predetermined distance above the base; 26. The simulated surgical model of claim 25.

28. 1. A simulated surgical model for identifying when an amount of force exceeding a predetermined amount is applied during a simulated surgical procedure, comprising: With the base, a post removably connected to the base; a plurality of strips connecting the base to the posts; Including, During a first state, the post rests on the base, and during a second state, the post is detached from the base and pulled a predetermined distance above the base. Simulated surgical model.

29. 30. The simulated surgical model of claim 28, wherein the plurality of strips are manufactured as one piece with the post.

30. 30. The simulated surgical model of claim 28 or claim 29, wherein the post is removably connected to the base through an opening that provides an interference type fit between the post and the base.

31. 1. A simulated surgical model for identifying when an amount of force exceeding a predetermined amount is applied during a simulated surgical procedure, comprising: a base having a plurality of pegs at predetermined locations; a post having one or more holes at predetermined locations; Including, In a first state, the one or more holes are configured to releasably connect with the plurality of pegs, and in a second state, one or more of the holes are decoupled from their respective pegs, the transition from the first state to the second state notifying a user when an amount of force being applied to a simulated surgical model exceeds a predetermined amount. Simulated surgical model.

32. 32. The simulated surgical model of claim 31, wherein the one or more holes are associated with a flap attached to the post.

33. 32. The simulated surgical model of claim 31, wherein the one or more holes are associated with an attachment or platform associated with the post.

34. 34. The simulated surgical model of claim 33, wherein the attachment or platform is also at least partially connected to the base.

35. 1. A surgical training model for developing and practicing skills associated with laparoscopic surgical procedures, comprising: a force sensing mechanism associated with a post having a first state and a second state, the force sensing mechanism being hidden from a user in the first state and being made visible to the user in the second state, the transition from the first state to the second state notifying a user when an amount of force being applied to the post exceeds a predetermined amount; A surgical training model including:

36. Further including a post, the force sensing mechanism is an indicator or protrusion positioned on the post; the indicator or protrusion is positioned beneath the model during the first condition; the transition from the first state to the second state occurs through an opening in the model through which the indicator or protrusion travels until it is visible to the user from beneath the model.

36. A surgical training model according to claim 35.

37. 1. A simulated surgical model for identifying when an amount of force exceeding a predetermined amount is applied during a simulated surgical procedure, comprising: With the base, a post removably connected to the base; Including, the model having a first state in which the post is connected to the base at the predetermined location and a second state in which the post is disconnected from the base at the predetermined location, the transition from the first state to the second state notifying a user when an amount of force being applied to the post exceeds a predetermined amount. Simulated surgical model.

38. 38. The simulated surgical model of claim 37, wherein the post is releasably connected through one or more pegs positioned on the base.

39. 38. The simulated surgical model of claim 37, wherein the post is removably connected through a hole that provides an interference type fit between the post and the base.

40. a force sensing mechanism for identifying when an amount of force exceeding a predetermined amount is being applied during a simulated surgical procedure, A first state and a second state, Including, In the first state, a portion of the model is configured to releasably connect to a different portion of the model; In the second state, the portion of the model is separated from the different portion of the model; and notifying a user when a transition from the first state to the second state results in an amount of force being applied to the model exceeding a predetermined amount. Force perception mechanism.

41. 41. The force sensing mechanism of claim 40, wherein the first state corresponds to a state in which the post is removably connected to the base.

42. 42. The force sensing mechanism of claim 41, wherein the post is removably connected to the base through an interference type mating hole.

43. 41. The force sensing mechanism of claim 40, wherein the first state corresponds to a state in which a hole in the body is releasably connected to a peg associated with a base.

44. 41. The force sensing mechanism of claim 40, wherein the first state corresponds to a state in which a tether of a body is releasably connected to the base through a slot in the base.

45. 41. The force sensing mechanism of claim 40, wherein the first state corresponds to a state in which a flap of the post is removably connected to the base.

46. 46. ​​The force sensing mechanism of claim 45, wherein the flap of the post is removably connected to a peg associated with the base.

47. 1. A surgical training model for developing and practicing skills associated with laparoscopic surgical procedures, comprising: a force sensing mechanism associated with the post and including a first state and a second state; Including, In the first state, the force sensing mechanism is hidden from a user; In the second state, the force sensing mechanism is made visible to the user; and a transition from the first state to the second state notifying a user when an amount of force being applied to the post exceeds a predetermined amount. Surgical training model.

48. 48. The surgical training model of claim 47, wherein the force sensing feature is a marking positioned on the model beneath the base.

49. 48. The surgical training model of claim 47, wherein the force sensing feature is a protrusion positioned on the model beneath the base.

50. 50. The surgical training model of claim 48 or claim 49, wherein the force sensing mechanism is configured to be pulled from its position beneath the base to a different position above the base, thereby making the force sensing mechanism visible to the user.

51. a force perception mechanism for identifying when an amount of force exceeding a predetermined amount is being applied to the phantom during a simulated surgical procedure, an indicator associated with a portion of the model and having a first state and a second state; Including, In the first state, the indicator is hidden from a user; In the second state, the indicator is made visible to the user; and transitioning from the first state to the second state notifies a user when the amount of force being applied to the post exceeds a predetermined amount. Force perception mechanism.

52. 52. The force sensing mechanism of claim 51, wherein the indicator is a protrusion.

53. 52. The force sensing mechanism of claim 51, wherein the indicator is a marking.

54. 54. A force perception mechanism according to claim 52 or claim 53, wherein the portion of the model associated with the indicator is configured to be pulled, thereby repositioning the indicator and making it visible to the user.

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