Dental surgery simulator

Abstract

The invention relates to a dental surgery simulator. The invention provides a dental surgery simulator (1) comprising a support structure supporting a display housing (6) and a parallel robot (40), a display screen (9) disposed in the display housing (6), a computer (80) configured to simulate a dental surgery or treatment, the parallel robot (40) controlled by the computer (80), the parallel robot providing at least three translational degrees of freedom, the parallel robot (40) is controlled by the computer (80) to simulate a dental procedure or treatment by providing haptic force feedback via the parallel robot (40).

Description

[0001] This application is a divisional application of the Chinese patent application with the application date of August 4, 2020, application number "202080056277X", and invention name "Device and method for simulating dental surgery". Technical Field

[0002] The present disclosure relates to apparatus and methods for simulating medical and dental procedures and methods, in particular apparatus and methods for simulating the activities of a physician, dentist, dental / oral / maxillofacial surgeon, dental hygienist, or dental therapist using virtual, mixed, and / or augmented reality. Background Art

[0003] Dentistry, also known as dentistry and oral medicine, is the branch of medicine that encompasses the study, diagnosis, prevention, and treatment of diseases, disorders, and conditions of the oral cavity, typically in the dentition, but also in the oral mucosa, and adjacent and related structures and tissues, particularly in the maxillofacial (jaw and face) region. Dentistry encompasses practices related to the oral cavity, in the form of dental procedures and treatments performed by dentists, dental surgeons, oral surgeons, maxillofacial surgeons, dental hygienists, and dental therapists.

[0004] Dental students need training facilities, and using real patients has obvious disadvantages.

[0005] Dental simulators for simulating dental surgery are known in the art. These simulators are used to train dental students, thereby reducing the need for training on plastic model heads with plastic model teeth (which do not provide accurate simulations, do not allow objective assessment or tracking of work, and are not environmentally friendly) and reducing the need for training on real patients. Known dental simulators include a computer that controls the simulation and hosts a virtual environment, a display screen that displays the simulation environment, and one or two handpieces connected to the computer to provide input. The simulation environment includes an object, a virtual set of teeth, a virtual version of the tool controlled by the handpiece, and a virtual version of the handpiece itself. The tool can be a surgical instrument (scalpel, syringe, etc.) or other device (such as a mirror or probe). The handpiece is connected to a sensor that determines its position and orientation, which is used to control (display) the position of the tool in the virtual environment. Typically, one of the handpieces is mounted on a tactile feedback system, through which the computer controls the force felt by the user through the handpiece.

[0006] The stationary U-shaped guide rail or the like serves as a resting place for the hands / fingers of the dental student (user). In a real dental surgery or treatment, the dentist usually places his fingers on the patient's teeth and jaws, and the simulation using a single fixed U-shaped guide rail in known dental simulators is not a realistic simulation.

[0007] A visual display screen is provided between the user's eyes and the handpieces and guide rails and presents a virtual environment showing a virtual set of teeth on a virtual jaw. Known simulators include a computer that controls the simulation and hosts the virtual environment, a display screen that displays the simulated environment, and one or two handpieces connected to the computer to provide input / output. The simulated environment includes objects, as well as virtual versions of tools controlled by the handpieces. The tools may be surgical instruments (scalpels, syringes, etc.) or other devices (such as mirrors or probes). The handpieces are connected to sensors that determine their position and are used to control the position of the tools in the virtual environment. One of the handpieces is mounted on a tactile feedback system that allows the computer to control the forces felt by the user through the handpiece, thereby enabling a more realistic simulation. Thus, a virtual version of the handpiece is displayed on the display screen, but the user cannot see his or her own fingers or hands, which is a disadvantage because it deprives the user of important visual input. Summary of the Invention

[0008] It is an object to provide a dental simulator that overcomes or at least reduces at least one of the above mentioned problems.

[0009] The aforementioned and other objects are achieved by the features of the independent claims. Further implementations emerge from the dependent claims, the description and the drawings.

[0010] According to a first aspect, a dental surgery simulator is provided, comprising: a support structure, a display screen, a computer configured to simulate dental surgery or treatment, a linkage device suspended from the support structure, the linkage device being controlled by the computer to simulate the medical surgery or treatment by providing tactile force feedback, a handpiece operably coupled to the linkage device and configured to be held in the hand of a user and manipulated by the user in a workspace in real space, a phantom upper jaw and a phantom lower jaw supported by the support structure and arranged in the workspace, the phantom lower jaw being preferably arranged to be movable relative to the phantom upper jaw, the computer being configured to display a virtual environment on the display screen, the virtual environment comprising at least one virtual tooth co-positioned with the phantom upper jaw or the phantom lower jaw.

[0011] By providing phantom upper and lower jaws, computer simulations of dental procedures become more realistic for users due to the mixed reality created by the presence of the upper and / or lower jaws. The presence of the phantom jaws, on which users can support their hands and fingers, closely mimics how a dentist would support their hands and fingers on a real patient, enhancing the computer simulation experience. Furthermore, the visual presence of the upper and lower jaws provides a more realistic representation of the working environment with a real patient, thereby providing a more realistic simulation.

[0012] According to a possible implementation of the first aspect, the upper jaw and the lower jaw of the model are movable relative to the supporting structure, and the dental surgery simulator includes one or more sensors configured to sense the position and orientation of the upper jaw and the lower jaw of the model relative to the supporting structure, wherein the computer receives the position and orientation of the upper jaw and the lower jaw of the model through the one or more sensors, and the computer is configured to adjust the orientation and position of at least one virtual tooth according to the movement of the upper jaw or the lower jaw of the model, so that when the upper jaw or the lower jaw of the model moves, the at least one virtual tooth remains co-positioned with the upper jaw or the lower jaw of the model on the display screen.

[0013] According to a possible implementation of the first aspect, the phantom upper jaw and the phantom lower jaw can be manually moved by a user.

[0014] According to a possible implementation of the first aspect, the computer is configured to display at least a portion of the virtual upper jaw and a portion of the virtual lower jaw, and the computer is configured to co-position the virtual upper jaw with the phantom upper jaw and co-position the virtual lower jaw with the phantom lower jaw on the display screen, even when the phantom upper jaw or the phantom lower jaw moves.

[0015] According to a possible implementation of the first aspect, the phantom mandible is suspended on the phantom mandible via a hinge mechanism, such as a four-bar kinematic chain, preferably a hinge mechanism that simulates the movement of a human jaw.

[0016] According to a possible implementation of the first aspect, the phantom lower jaw is suspended from the phantom upper jaw to allow movement between an open position and a closed position.

[0017] According to a possible implementation of the first aspect, the dental surgery simulator comprises a position sensor configured to generate a signal indicating a position of a phantom lower jaw relative to an upper jaw of the phantom.

[0018] According to a possible implementation manner of the first aspect, the closed position corresponds to a position for checking occlusal reduction.

[0019] According to a possible implementation of the first aspect, the computer is configured to display a virtual upper tooth set for the upper jaw of the phantom and a virtual lower tooth set for the lower jaw of the phantom on a display screen, thereby allowing a visual occlusion check of the virtual tooth sets in a closed position.

[0020] According to a possible implementation of the first aspect, the upper jaw of the model is suspended from the support structure to allow rotation in one, two or three degrees of freedom, preferably with the rotation center of each degree of freedom located between the upper jaw and the lower jaw of the model.

[0021] According to a possible implementation of the first aspect, preferably one, two or three degrees of freedom of rotation are imparted manually, and wherein the dental surgery simulator comprises one or more rotational position sensors for sensing the rotation of the phantom jaw for each of the one to three degrees of freedom.

[0022] According to a possible implementation of the first aspect, the computer receives signals from one or more rotational position sensors, and wherein the computer is configured to adjust the simulation of the dental procedure or treatment according to the signals from the rotational position sensors.

[0023] According to a possible implementation of the first aspect, the upper jaw of the mold is suspended from the supporting structure by a first mechanism, which allows the upper jaw to rotate around a first horizontal axis Y set in the working space without intruding the working space. The first mechanism preferably includes a remote center linkage device, preferably two spaced-apart parallel remote center linkage devices.

[0024] According to a possible implementation of the first aspect, the upper jaw of the phantom is suspended from the support structure via a second mechanism, wherein the second mechanism allows the upper jaw of the phantom to rotate around a second horizontal axis provided in the working space, and the second mechanism does not intersect the working space.

[0025] According to a possible implementation of the first aspect, the upper jaw of the phantom is suspended from the support structure via a third mechanism, wherein the third mechanism allows the upper jaw of the phantom to rotate around the vertical axis Z, and the third mechanism does not intersect the working space.

[0026] According to a possible implementation of the first aspect, the mold upper jaw comprises an upper support member having a detachable upper jaw element detachably attached thereto, and wherein the mold lower jaw comprises a lower support member having a detachable lower jaw element detachably attached thereto.

[0027] According to a possible implementation of the first aspect, the removable upper jaw element is a universal upper jaw element, which preferably does not have / define teeth, and wherein the removable lower jaw element is a universal lower jaw element, which preferably does not have / define teeth.

[0028] According to a possible implementation of the first aspect, the removable maxillary element is a specific maxillary element provided with model teeth, the model teeth are preferably removably attached to the specific maxillary element, and the specific maxillary element with its model teeth is preferably an accurate replica of a part of a real human maxillary element with its teeth, and wherein the removable mandibular element is a specific mandibular element provided with model teeth, the model teeth are preferably removably attached to the specific mandibular element, and the specific mandibular element with its model teeth is preferably an accurate replica of a part of a real human mandibular element with its teeth.

[0029] According to a possible implementation manner of the first aspect, the computer is provided with a virtual model of the specific upper jaw component and / or the specific lower jaw component.

[0030] According to a possible implementation of the first aspect, the phantom upper jaw and the phantom lower jaw are part of a phantom head, and the phantom head and its phantom lower jaw and phantom upper jaw are preferably configured to move in unison with each other.

[0031] According to a possible implementation of the first aspect, the computer is configured to guide the user to install / remove a specific upper or lower jaw element on / from the support member, and the computer is preferably also configured to guide the user to install / remove the model teeth on or from the specific jaw element.

[0032] According to one possible implementation of the first aspect, a computer is coupled to a display screen, and wherein the dental surgery simulator is configured to project an image from the display screen to the user's eyes through a partially transparent reflective element, while allowing the user to view the workspace, the handpiece, the phantom upper jaw, and the phantom lower jaw through the partially transparent reflective element.

[0033] According to a possible implementation of the first aspect, the computer is configured to simulate a medical or dental operation or treatment through force feedback in response to a user manipulating the handpiece in a workspace.

[0034] According to a possible implementation of the first aspect, the phantom upper jaw and / or the phantom lower jaw is a segmented phantom jaw, wherein at least one segment is detachable.

[0035] By using a segmented phantom jaw, in which at least one or more or all segments can be removed and, of course, also reattached, it is possible to avoid abutments between the haptic arm and the phantom jaw, which can occur in particular when simulating activities involving the treatment of virtual teeth associated with the mandible. In other words, in some cases, a portion of the phantom jaw obstructs the haptic arm, and by removing the relevant segmented phantom jaw segment, space is left for the haptic arm, while the majority of the phantom jaw remains for the user to use as a hand support and to provide realism for the simulation.

[0036] According to a second aspect, there is provided a dental surgery simulator comprising:

[0037] A support structure configured to simulate a dental procedure or treatment on a computer,

[0038] A linkage device suspended from a support structure, the linkage device being controlled by a computer to simulate a medical procedure or treatment by providing tactile force feedback configured to simulate a dental procedure or treatment, a handpiece operably coupled to the linkage device and configured to be held in a user's hand and manipulated by the user in a real-space workspace, a phantom upper jaw movably supported by the support structure and arranged in the workspace, wherein the phantom upper jaw is suspended from the support structure by a mechanism that allows the phantom upper jaw to rotate about at least one axis set in the workspace without the mechanism intersecting the workspace.

[0039] By providing a linkage that does not intrude upon the workspace, the phantom head can be used in computer simulations of dental procedures or treatments without interfering with the workspace required for handpiece movement.

[0040] According to a possible implementation of the second aspect, the upper jaw of the mold is suspended from the support structure by a first mechanism, which allows the upper jaw to rotate around a horizontal axis set in the working space without intruding the working space. The first mechanism preferably includes at least one spaced-apart parallel remote center linkage device.

[0041] According to a possible implementation of the second aspect, the upper jaw of the mold is suspended from the support structure by a second mechanism, which allows the upper jaw of the mold to rotate around a horizontal axis, and the second mechanism does not intersect with the working space. The second mechanism preferably includes an L-shaped plate extending between the mold head and the upper jaw of the mold.

[0042] According to a possible implementation of the second aspect, the upper jaw of the mold is suspended from the supporting structure by a third mechanism, and the third mechanism allows the upper jaw of the mold to rotate around the vertical axis, and the third mechanism does not intersect with the working space. The third mechanism preferably includes a hinge pin that connects the first mechanism to the L-shaped plate and allows the L-shaped plate to rotate around the vertical axis.

[0043] According to a third aspect, there is provided an apparatus for simulating or training dental surgery or treatment, the apparatus comprising: a handpiece configured to be held in a user's hand and manipulated by the user in a workspace in real space, a haptic arm controlled by a computer configured to simulate dental surgery or treatment, the handpiece being mechanically connected to the haptic arm, a powered dental handpiece having a motor for driving a dental drill, a support for supporting at least one model tooth in a workspace.

[0044] By providing both a handpiece for computer simulation of dental procedures or treatments and a handpiece for physical simulation of dental procedures, both types of training can be performed by a single machine, resulting in significant cost and space savings.

[0045] According to one possible implementation of the third aspect, the powered dental handpiece is provided with electrical power or pneumatic power via a cable connected to the powered dental handpiece.

[0046] According to a possible implementation of the third aspect, the device comprises at least one model jaw for supporting at least one model tooth.

[0047] According to a possible implementation manner of the third aspect, the model tooth is at least partially made of a polymer material.

[0048] According to one possible implementation of the third aspect, the computer has at least a first operating mode for simulating a dental procedure or treatment using a handpiece and a second operating mode for training a dental procedure or treatment using a powered dental handpiece.

[0049] According to a possible implementation manner of the third aspect, the handpiece is a passive handpiece that does not include any motor and is not configured to operate a dental drill.

[0050] According to a fourth aspect, a medical surgery simulator is provided, comprising: a handpiece configured to be held in a user's hand and manipulated by the user in a real-space workspace, and a linkage device controlled by a computer configured to simulate medical surgery or treatment, the linkage device comprising an elongated main coupling, a first crank, a second crank and a third crank, a first actuator driving the first crank, a second actuator driving the second crank, and a third actuator driving the third crank, the handpiece being connected to the end of the main coupling by a mechanical joint, the first crank being arranged to actuate the main coupling in a longitudinal direction The main connecting member is a main connecting member, the second crank is arranged to actuate the main connecting member in a first lateral direction, and the third crank is arranged to actuate the main connecting member in a second lateral direction different from the first lateral direction, the first crank is directly coupled to the main connecting member through a second mechanical joint, the second crank is coupled to the main connecting member through a first connecting rod, the first connecting rod is coupled to the second crank at a first end and the first connecting rod is coupled to the main connecting member at a second end, and the third crank is coupled to the main connecting member through a second connecting rod, the second connecting rod is coupled to the third crank at a first end, and the second connecting rod is coupled to the main connecting member at a second end.

[0051] The linkage of the medical surgery simulator is not complex and is therefore reliable and inexpensive because it comprises a relatively small number of components. Furthermore, the linkage is adapted to provide a cuboid workspace whose sides are vertical and horizontal.

[0052] In a first possible implementation of the fourth aspect, the first crank is connected to the main connecting member at a first axial position, the first connecting rod is coupled to the main connecting member at a second axial position between the end and the first axial position, and the second connecting rod is coupled to the main connecting member at a third axial position between the end and the first position, the second and third axial positions are preferably substantially the same.

[0053] In a second possible implementation of the fourth aspect, the main connecting member includes a three-dimensional force sensor for sensing the three-dimensional force applied by the user to the handpiece, the three-dimensional force sensor is arranged between the end position and the second and / or third axial position, and the three-dimensional force sensor is preferably an integral part of the main connecting member.

[0054] In a third possible implementation of the fourth aspect, the first, second and / or third crank is coupled to a rotational position sensor or encoder.

[0055] In a fourth possible implementation of the fourth aspect, the first, second and / or third actuator is a rotary actuator.

[0056] In a fifth possible implementation manner of the fourth aspect, the respective rotation axes of the first, second and third cranks are arranged orthogonally to each other.

[0057] In a sixth possible implementation of the fourth aspect, the first connecting rod extends substantially horizontally, the second connecting rod extends substantially vertically, and the rotation axis of the first crank extends substantially vertically.

[0058] In a seventh possible implementation of the fourth aspect, the computer is configured to simulate a medical operation or treatment by utilizing tactile feedback of the linkage device, preferably tactile force control feedback, and by utilizing visual feedback of the display screen.

[0059] In an eighth possible implementation of the fourth aspect, the medical surgery simulator includes a reference member, wherein the first, second, and third cranks are mounted on the reference member.

[0060] In a ninth possible implementation of the fourth aspect, the medical surgical simulator comprises a reference member, wherein the linkage device provides at least six independent degrees of freedom for the handpiece relative to the reference member.

[0061] In a tenth possible implementation manner of the fourth aspect, a linkage device connects the handpiece to the reference piece.

[0062] In an eleventh possible implementation of the fourth aspect, the handpiece includes an inertial measurement unit, which is preferably configured to generate directional data indicating the rotation direction of the handpiece, preferably the rotation direction of the handpiece in real space and / or relative to a reference piece.

[0063] In a twelfth possible implementation of the fourth aspect, the free end of the first crank is coupled to the main coupling, preferably by a mechanical joint providing relative movement with at least two degrees of freedom between the main coupling and the first crank, such as for example a universal joint.

[0064] In a thirteenth possible implementation manner of the first aspect, the second lateral direction is substantially perpendicular to the first lateral direction.

[0065] In a fourteenth possible implementation of the fourth aspect, the computer is configured to simulate a medical procedure or treatment by using a signal from a three-dimensional force sensor as input and controlling the velocity of the end accordingly.

[0066] According to a fifth aspect, a medical surgery simulator is provided, comprising a handpiece coupled to a tactile force feedback system providing tactile force feedback, the force feedback system comprising at least one actuator, a control system comprising: a virtual model configured to calculate virtual forces and a force sensor configured to sense forces applied to the handpiece, the virtual model receiving a signal representing a velocity of the handpiece, a summing point for summing the virtual force and the sensed force, a lead-lag compensator receiving an output of the summing point, a PI or PID controller receiving an output of the lag-lead compensator, a motor driver receiving a velocity command from the PI or PID controller, and at least one actuator electrically driven by the motor driver.

[0067] By using a lead-lag compensator in a medical surgery simulator, high frequencies caused by contact instability or system resonance are eliminated from the input signal of the PI or PID controller, making the operation of the medical surgery simulator more stable and smooth with a realistic feel.

[0068] In a possible implementation of the fifth aspect, the virtual model receives a signal indicating the orientation of the handpiece 30 .

[0069] In another possible implementation of the second aspect, the virtual model receives a signal indicating a rotation speed of the virtual drill.

[0070] According to a sixth aspect, a dental surgery simulator is provided, comprising a computer configured to simulate dental surgery or treatment, a handpiece configured to be held in a user's hand and manipulated by the user in a workspace in a real space, the computer configured to generate an image of the simulated dental surgery for display on a display screen, a partially transparent reflective element configured to reflect the image on the display screen to the user's eyes, and a workspace configured to be visible to the user through the partially transparent reflective element.

[0071] By providing a partially transparent reflective screen, users can see their own hands while training for medical procedures. This provides important visual feedback that greatly enhances the user experience. The resulting mixed reality enhances the overall user experience.

[0072] According to a sixth possible implementation of the first aspect, the dental surgery simulator is configured to reflect an image from the display screen to the user's eyes by reflection on a partially transparent reflective element, and is configured to mix the image with the user's view of the workspace W through the partially transparent reflective element.

[0073] According to a first possible implementation of the sixth aspect, the image on the display screen is reflected to the user's eyes, and when the user views the partially transparent reflective element from the viewing space, the workspace can simultaneously be visible to the user through the partially transparent reflective element.

[0074] According to a third possible implementation manner of the sixth aspect, the display screen is a three-dimensional display screen.

[0075] According to a fourth possible implementation manner of the sixth aspect, the computer is configured to send a stereoscopic image to a stereoscopic display screen.

[0076] According to a fifth possible implementation manner of the sixth aspect, the stereoscopic display screen is an automatic stereoscopic display screen.

[0077] According to a sixth possible implementation manner of the sixth aspect, the computer is configured to generate an image of a virtual handpiece co-located with the handpiece, and the image is preferably a stereoscopic image.

[0078] According to a seventh possible implementation of the sixth aspect, the computer is configured to provide a three-dimensional virtual environment, wherein the three-dimensional virtual environment includes a first virtual tool having a first virtual position and a first virtual orientation, the first virtual tool corresponding to the handpiece in size and shape, and the first virtual tool is co-positioned with the handpiece.

[0079] According to an eighth possible implementation manner of the sixth aspect, the partially transparent reflective element is a partially transparent mirror or a semi-transparent mirror.

[0080] According to a ninth possible implementation of the sixth aspect, the dental surgery simulator is provided with adjustable lighting on the workspace.

[0081] According to a tenth possible implementation of the sixth aspect, the dental surgery simulator is provided with a phantom upper jaw and a phantom lower jaw, both of which are arranged in a working space.

[0082] According to an eleventh possible implementation of the sixth aspect, the dental surgery simulator is provided with a phantom head, which is arranged in the working space, and the phantom head preferably includes a phantom upper jaw and a phantom lower jaw.

[0083] According to a seventh aspect, a method for simulating dental surgery or treatment is provided, comprising: providing a dental surgery simulator, the dental surgery simulator comprising a handpiece configured to be held in a user's hand and manipulated by the user in a workspace in a real space, generating an image of a virtual environment with a simulated dental surgery or treatment on a display screen, reflecting the image to the user through a partially transparent reflective element, and allowing the user to simultaneously view the workspace and the image of the virtual environment reflected by the partially transparent reflective element through the partially transparent reflective element.

[0084] According to a first possible implementation of the seventh aspect, the workspace comprises at least one movable phantom jaw and / or a movable phantom head, and wherein the virtual environment comprises at least one virtual jaw with virtual teeth, and the method comprises adjusting the position of the virtual jaw with virtual teeth to maintain co-positioning with the phantom jaw.

[0085] According to an eighth aspect, a dental surgery simulator is provided, comprising: a computer configured to simulate dental surgery or treatment, a parallel robot controlled by the computer, the parallel robot providing at least three translational degrees of freedom, the parallel robot being controlled by the computer to simulate dental surgery or treatment by providing tactile force feedback via the parallel robot, a handpiece operably coupled to the parallel robot by a mechanism providing at least three rotational degrees of freedom, the handpiece being configured to be held in a user's hand and manipulated by the user in a real-space workspace, and an automatic stereoscopic display screen, the computer being configured to generate a stereoscopic image of the simulated dental surgery for display on the automatic stereoscopic display screen, and the computer being configured to generate a stereoscopic image of a virtual handpiece co-positioned with the handpiece.

[0086] By providing a dental surgery simulator with a force feedback parallel robot, combined with an autostereoscopic display, highly realistic training can be provided to dental practitioners or students without the need for trainees to use 3D (shutter) glasses.

[0087] According to a possible implementation of the eighth aspect, a dental surgery simulator includes a parallel robot controlled by a computer, the parallel robot providing at least three translational degrees of freedom, the parallel robot being controlled by a computer to simulate dental surgery or treatment by providing tactile force feedback via the parallel robot, and the handpiece being operably coupled to the parallel robot via a mechanism providing at least three rotational degrees of freedom.

[0088] According to a possible implementation of the eighth aspect, the parallel robot includes an actuator for each translational degree of freedom.

[0089] According to a possible implementation of the eighth aspect, the dental surgery simulator includes a sensor for sensing the direction of the handpiece.

[0090] According to a possible implementation of the eighth aspect, the dental surgery simulator includes a partially transparent reflective element, which is arranged to reflect images from the autostereoscopic display screen to the user's eyes, and the workspace is arranged to be visible to the user through the partially transparent reflective element.

[0091] According to a possible implementation of the eighth aspect, the computer is configured to generate a three-dimensional virtual environment including a first virtual tool having a first virtual position and a first virtual orientation, wherein the first virtual tool preferably corresponds to the handpiece in size and shape, and the computer is configured to co-position the first virtual tool with the handpiece.

[0092] According to a ninth aspect, a dental surgery simulator is provided, comprising: a computer configured to simulate dental surgery or treatment, a reference piece, a first handpiece simulating a dental drill, the first handpiece being configured to be held in a user's hand and manipulated by the user in a workspace in real space, a linkage coupled to the reference piece, the linkage being controlled by the computer, the computer being configured to simulate dental surgery or treatment by providing tactile feedback via the linkage, a second handpiece for simulating a dental mirror, the second handpiece being configured to be held in a user's hand and manipulated by the user in a workspace in real space, a main coupling coupled to the reference piece by one or more joints providing a first and a second degree of freedom, and a third coupling coupled to the reference piece by one or more joints providing a first and a second degree of freedom. and a secondary coupling member coupled to the primary coupling member by one or more joints providing fifth and sixth degrees of freedom, the second hand piece being connected to the secondary coupling member by one or more joints providing fifth and sixth degrees of freedom to form a serial chain connecting the second hand piece to the reference member in six degrees of freedom, a first sensor for sensing movement in the first degree of freedom, a second sensor for sensing movement in the second degree of freedom, a third sensor for sensing movement in the third degree of freedom, the first, second and third position sensors being connected to computer data, and an inertial measurement unit arranged in the second hand piece, the inertial measurement unit being connected to computer data, and the inertial measurement unit being configured to sense movement in at least the fourth, fifth and sixth degrees of freedom.

[0093] The combination of three position sensors and an inertial measurement unit in the handpiece provides a relatively simple yet still accurate system for determining the exact position of the handpiece relative to the reference piece, as the signals from the position sensors can be used to compensate the inertial measurement unit.

[0094] In a first possible implementation of the ninth aspect, the handpiece is connected to the secondary coupling via one or more joints providing a sixth degree of freedom, wherein the sixth degree of freedom allows the handpiece to rotate around the axis of the handpiece and the inertial measurement unit is configured to sense the sixth degree of freedom.

[0095] In a second possible implementation manner of the ninth aspect, the first sensor, the second sensor, or the third sensor is a rotational position sensor.

[0096] In a third possible implementation of the ninth aspect, the primary link is an elongated link coupled to the reference member by a third pivot joint allowing the primary link to rotate about its longitudinal axis to achieve the first degree of freedom.

[0097] In a fourth possible implementation of the ninth aspect, the first sensor is a rotational position sensor configured to sense rotation around a longitudinal axis of the main coupling.

[0098] In a fifth possible implementation of the ninth aspect, the primary link is an elongated link coupled to the reference member by a hinge that allows the primary link to rotate about the transverse axis to obtain a second degree of freedom.

[0099] In a sixth possible implementation of the ninth aspect, the second position sensor is a rotational position sensor configured to sense rotation of the main coupling about the transverse axis.

[0100] In a seventh possible implementation of the ninth aspect, the secondary link is an elongated link coupled to the primary link by a third hinge that allows the secondary link to rotate about the transverse axis to obtain a third degree of freedom.

[0101] In an eighth possible implementation of the ninth aspect, the third sensor is a rotational position sensor configured to sense rotational movement of the secondary coupling about the transverse axis.

[0102] In a ninth possible implementation of the ninth aspect, the secondary link is an elongated link coupled to the primary link by a second pivot joint allowing the secondary link to rotate about its longitudinal axis to obtain a fourth degree of freedom.

[0103] In a tenth possible implementation of the ninth aspect, the medical surgery simulator includes a tertiary connector coupled to a quadruple connector, the tertiary connector coupled to a primary connector or a secondary connector, and the quadruple connector coupled to a third sensor to form a serial chain, which converts the rotation of the secondary connector around the transverse axis of the secondary connector into rotational motion of the third sensor.

[0104] In an eleventh possible implementation of the ninth aspect, the medical surgery simulator includes a second hinge providing a fifth degree of freedom to the handpiece.

[0105] In a twelfth possible implementation of the ninth aspect, the medical surgical simulator includes a fourth pivot joint allowing the handpiece to rotate about an axis of the handpiece to provide a sixth degree of freedom.

[0106] In a thirteenth possible implementation of the ninth aspect, the medical surgery simulator includes a rotational position sensor inside the handpiece for sensing a rotation of the handpiece around an axis of the handpiece.

[0107] In a fourteenth possible implementation of the ninth aspect, the inertial measurement unit is configured to sense rotation of the handpiece around an axis of the handpiece.

[0108] In a fifteenth possible implementation of the ninth aspect, the inertial measurement unit is configured to sense motion in up to six degrees of freedom, preferably three rotational degrees of freedom, and wherein the computer is configured to use signals from the first, second and / or third sensors as a reference for calibrating the inertial measurement unit.

[0109] According to the tenth aspect, a medical surgery simulator is provided, comprising: a handpiece configured to be held in the hand of a user and manipulated by the user in a real-space workspace, a linkage device controlled by a computer configured to simulate medical surgery or treatment, the handpiece comprising an internal part extending into an external part, wherein the external part is configured to rotate around the internal part, a portion of the internal part protrudes from the external part, the portion being coupled to the linkage device via a joint having at least two degrees of freedom, an inertial measurement unit mounted to the internal part and coupled to the computer, and a rotational position sensor for sensing rotational movement of the external part relative to the internal part, the rotational position sensor being coupled to the computer, at least a first portion of the rotational position sensor being mounted on the internal part, and the first portion being connected to the computer via a cable guided or supported by the internal part.

[0110] The arrangement of the inner and outer portions of the handpiece increases the freedom a user has in manipulating the handpiece with their hands. The arrangement in which at least a first portion of the rotation sensor is mounted on the inner portion allows the outer portion to rotate infinitely relative to the inner portion, thereby providing the handpiece with unrestricted rotation about its longitudinal axis. Because the rotational position sensor can be at least partially disposed on the inner portion, the rotation sensor can be connected to a computer via a cable without the need for slip rings or the like to allow rotation, as the cable is not exposed to rotation. The absence of slip rings or the like in the connection between the rotational position sensor and the computer provides a more reliable connection between the rotational position sensor and the computer.

[0111] In a first possible implementation of the tenth aspect, the inertial measurement unit is configured to generate directional data indicating a rotational direction of the handpiece.

[0112] In a second possible implementation of the tenth aspect, the inertial measurement unit is coupled to the computer via a cable guided or supported by the internal portion.

[0113] In a third possible implementation of the tenth aspect, the medical surgery simulator includes a first rotary bearing located between the inner portion and the outer portion, and preferably includes a second rotary bearing axially spaced apart from the first rotary bearing.

[0114] In a fourth possible implementation of the tenth aspect, the outer part is arranged to rotate around the longitudinal axis of the inner part.

[0115] In a fifth possible implementation of the tenth aspect, the inner part is elongated and connected to the joint at a first end of the inner part, and the rotational position sensor is arranged at or near a second end of the inner part, and the second end is located inside the outer part.

[0116] In a sixth possible implementation of the tenth aspect, the inertial measurement unit is configured to generate position and / or orientation data of the handpiece in real space, preferably relative to the reference piece.

[0117] In a seventh possible implementation of the tenth aspect, the coupling of the inertial measurement unit to the computer includes a data connection from the inertial measurement unit to the computer for transmitting position and / or orientation data.

[0118] In an eighth possible implementation of the tenth aspect, the coupling of the rotational position sensor to the computer includes a data connection from the rotational position sensor to the computer for transmitting the rotational position data.

[0119] In a ninth possible implementation of the tenth aspect, the outer portion has an unrestricted rotation relative to the inner portion.

[0120] In a tenth possible implementation of the tenth aspect, the longitudinal extent of the outer portion includes a proximal portion and a distal portion extending at a certain angle to the proximal portion, wherein the inner portion protrudes from the outer portion through the distal portion.

[0121] According to an eleventh aspect, a dental surgery simulator having a front and a back is provided, the dental surgery simulator comprising: a computer configured to simulate dental surgery or treatment, a linkage controlled by the computer, a handpiece coupled to the linkage and configured to be held in the hand of a user and manipulated by the user in a real-space workspace, a display coupled to the computer for displaying images generated by the computer, a base, a main structure having a substantially flat bottom, the linkage being at least partially housed in the main structure, and a column supporting the main structure above the base, having a distance between the substantially flat bottom and the base to create a space between the substantially flat bottom and the base, the column being height-adjustable to change the distance between the surface on which the base is placed and the substantially flat bottom to a range preferably including a distance of at least 70 to 80 cm, more preferably including a distance of at least 65 to 85 cm, the column (3) being laterally offset relative to the base and relative to the substantially flat bottom, the column extending from a position adjacent to the front of the base, preferably at the front of the base, to a position adjacent to the front of the main structure, preferably at the front of the main structure.

[0122] The substantially flat bottom and the space between the base allow the dental surgery simulator to take up less space, as it can be easily adapted to different room settings. In particular, the substantially flat bottom of the main housing and the height adjustability of the column allow the main housing to be placed on, for example, a workbench or tabletop, thereby saving valuable room space.

[0123] In a first possible implementation of the eleventh aspect, the space between the base and the flat bottom is an empty space intersecting only with the column.

[0124] In a second possible implementation of the eleventh aspect, the space is accessible from all lateral directions except where the column obstructs access.

[0125] In a third possible implementation of the eleventh aspect, the dental surgery simulator includes two or more posts, wherein the two or more posts are laterally offset and disposed on a same side of the base and the main housing.

[0126] In a fourth possible implementation of the eleventh aspect, the main housing is supported by only one column.

[0127] In a fifth possible implementation of the eleventh aspect, the space is open to the environment except where the space is shielded by a base, a substantially flat bottom or a column.

[0128] In a sixth possible implementation of the eleventh aspect, the column is height-adjustable for varying the distance between the base and the substantially flat bottom, preferably a motorized height-adjustable column.

[0129] In a seventh possible implementation of the eleventh aspect, the column includes a linear actuator for height adjustment.

[0130] In an eighth possible implementation of the eleventh aspect, the display screen is disposed in a display housing disposed above the main housing, and the display housing is preferably supported above the main housing by an arm connected to a column or the main housing.

[0131] In a ninth possible implementation of the eleventh aspect, the base includes a lower shell.

[0132] In a tenth possible implementation of the eleventh aspect, the main housing includes a reference member for supporting the linkage device.

[0133] In an eleventh possible implementation of the eleventh aspect, the base is configured to be placed on the floor, and preferably the base is on wheels.

[0134] In a twelfth possible implementation of the eleventh aspect, the computer is configured to generate an image of a simulated dental procedure or treatment for display on a display screen.

[0135] In a thirteenth possible implementation of the eleventh aspect, the post extends from the base to the main housing.

[0136] In a fourteenth possible implementation of the eleventh aspect, the column extends from a position adjacent to a side surface of the base to a position adjacent to a side surface of the main housing.

[0137] These and other aspects will become apparent from the embodiments described hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

[0138] In the following detailed portion of the present disclosure, various aspects, embodiments and implementations will be explained in more detail with reference to exemplary embodiments shown in the accompanying drawings, in which:

[0139] Figure 1 is an elevated view of a dental surgery simulator according to an embodiment,

[0140] Figure 2 yes Figure 1 A side view of the dental surgery simulator at a first height;

[0141] Figure 3 yes Figure 1 a side view of the dental surgery simulator at a second height lower than the first height;

[0142] Figure 4 Shown Figure 1 A front view of the display housing of the dental surgery simulator,

[0143] Figure 5 It passes through Figure 4 A cross-sectional view of a display housing also illustrating the workspace, the user's eyes, and the visual space,

[0144] Figure 6 yes Figure 1 A top view of the dental surgery simulator from the user's perspective onto the workspace through a semi-transparent mirror in the display housing, also showing the virtual environment through reflection from the semi-transparent mirror,

[0145] Figure 7 is Figure 1 Image of a mixed reality virtual environment displayed by a dental surgery simulator.

[0146] Figures 8 to 11 yes Figure 1 A top view of a specific phantom jaw used in the dental surgery simulator.

[0147] Figure 12 This is a top view of the model head and its mounting system using a specific mandible and a specific maxillary model.

[0148] Figure 13 yes Figure 12 Side view of the phantom head,

[0149] Figure 14 and 15 is Figure 1 Top view of the generic phantom jaw used in the dental surgery simulator.

[0150] Figure 16 yes Figure 12 A top view of the phantom head showing the three rotation axes of the phantom head relative to the dental surgery simulator, on which the universal phantom jaw is mounted,

[0151] Figure 17 and 18 yes Figure 16 A top view of the phantom head showing rotation around the Z and X axes.

[0152] Figure 19 and 20 yes Figure 12 Side view of the phantom head, illustrating the different positions of the phantom mandible relative to the phantom maxilla,

[0153] Figure 21 and 22 yes Figure 16 Side view of the phantom head, illustrating rotation around the Y axis,

[0154] Figures 23 to 26 are top and isometric views, respectively, of an embodiment of a linkage with its drive system and a handpiece connected to the linkage,

[0155] Figure 27 is a cross-sectional view through a handpiece according to an embodiment,

[0156] Figure 28 and 29 yes Figure 27 Side view of the handpiece,

[0157] Figure 30 is a top view of a dental surgery simulator including auxiliary tools according to another embodiment,

[0158] Figure 31 is a top view of an embodiment of the auxiliary tool,

[0159] Figure 32 and 33 They are Figure 31 End and side views of the auxiliary tool,

[0160] Figure 34 yes Figure 1 Schematic diagram of a dental surgery simulator, also showing the user's eyes and visual space,

[0161] Figure 35 is a schematic diagram of an embodiment of a control system that may be used in a dental surgery simulator,

[0162] Figure 36 Another embodiment of a dental surgery simulator is shown with the additional functionality of training drilling into plastic model teeth, and

[0163] Figure 37 and 38 An embodiment of a segmented phantom jaw for a dental surgery simulator is illustrated. DETAILED DESCRIPTION

[0164] With reference to the accompanying drawings, in particular Figures 1 to 7and 34, which show a first embodiment of a medical surgery simulator 1, in particular a dental surgery simulator 1 for simulating dental surgeries and treatments. The medical surgery simulator 1 is intended for training skills and abilities of medical professionals or students. In the case of the dental surgery simulator 1, the dental surgery simulator is intended for training skills and abilities of dentists, dental surgeons, oral surgeons, maxillofacial surgeons, dental hygienists and dental therapists. The users who receive dental surgery simulator training may be students or professionals. The dental surgery simulator 1 generally comprises: a first handpiece 30, which in this embodiment is a first handpiece 30 representing a dental drill handle; a base 2, which in this embodiment is a base having a lower housing for accommodating a computer 80; a column 3, which in this embodiment is a height-adjustable column; a main housing 4 accommodating a linkage 40 to which the first handpiece 30 is connected; a phantom head 10 and a support arm 5 supporting a display housing 6.

[0165] In one embodiment, the base 2 is a wheeled base that allows the user to easily roll the medical surgery simulator 1 to another location. A column 3 extends from the base 2 to the main housing 4 and supports the main housing 4 above the base 2, with a distance between the substantially flat bottom of the main housing 4 and the base 2 to create a space R between the substantially flat bottom and the base 2. The column 3 is laterally offset relative to the base 2 and the substantially flat bottom to allow access to the space R from all sides (except the side where the column 3 is arranged). In one embodiment, the column 3 extends from a position immediately adjacent to a side (front) of the base 2 to a position immediately adjacent to a side (front) of the main housing 4.

[0166] The space R between the base 2 and the flat bottom is an empty space R intersecting only the posts 3. The space R is accessible from all lateral directions except where the posts 3 block access.

[0167] In an embodiment (not shown), the dental surgery simulator 1 includes two or more columns 3 that are laterally offset and disposed on the same side of the base 2 and the main housing 4. In the illustrated embodiment, the main housing 4 is supported by only one column 3. The space R is open to the environment except where it is shielded by the base 2, the substantially flat bottom, or the column 3.

[0168] like Figure 2 and 3As shown by the double-line arrow in , the height of the main housing 4 can be adjusted by operation of the column 3, which in an embodiment is motorized, such as by an electric linear actuator. The column 3 supports the main structure above the base 2, with a distance between the substantially flat bottom of the main housing 4 and the base 2, thereby forming a space between the substantially flat bottom and the base 2. The height of the column is adjustable for changing the distance between the surface on which the base is placed (such as the floor) and the substantially flat bottom to a range preferably including a distance of at least 70 to 80 cm, more preferably a distance of at least 65 to 85 cm. The column 3 is laterally offset relative to the base 2 and relative to the substantially flat bottom. The column 3 extends from a position adjacent to the front face of the base 2, preferably at the front face of the base 2, to a position adjacent to the front face of the main structure 101, preferably at the front face of the main structure 101.

[0169] The phantom head 10 is suspended from the front of the main housing 4, and the display housing 6 is suspended from the main housing 4 via the support arm 5, so that when the height of the main housing 4 is adjusted, the phantom head 10, the display housing 6, and the first handpiece 30 move synchronously with the main housing 4. The main housing 4, the support arm 5, and the display housing 6 together form a main structure 1012, to which the phantom head 10 is also attached.

[0170] like Figure 2 As shown, the main housing 4 has a substantially flat bottom, which, along with the height adjustability, allows the main housing 4 to be positioned above a work surface or tabletop 85, thereby saving valuable training room space. Figure 3 The main housing is shown in a lowered position. The height adjustability also allows the working height of the dental surgery simulator 1 to be adjusted to the individual user, as the phantom head 10 and handpiece 30 will move up and down simultaneously with the main housing 4.

[0171] The medical surgery simulator 1 comprises a lower housing located on a base 2, in which a computer 80 and a power supply for the computer 80 and other electrical components of the medical surgery simulator 1 are arranged. In an embodiment, the medical surgery simulator 1 comprises more than one computer.

[0172] The computer 80 has a memory and a processor. The processor is arranged to execute software stored on the memory, in particular software configured to simulate a medical procedure or treatment, in particular in a training or teaching environment.

[0173] The computer 80 is connected to the display screen 9, the model in the workspace W, the linkage 40 mounted to the main housing 4, and the first handpiece 30 also arranged in the workspace W. The linkage 40 (hereinafter referred to as Figures 23 to 26The first hand piece 30 is mechanically connected to the first hand piece 30 (described in detail). The workspace W is a three-dimensional space in the real world, and the first hand piece 30 can be manipulated by the user within this space without being constrained by the linkage 40 (the constraints caused by the range of the end of the linkage to which the first hand piece 30 is connected in the orthogonal direction in the real space are limited).

[0174] The model represents a portion of the subject (e.g., a phantom upper jaw 13 and lower jaw 14 with or without a phantom set of teeth and with or without a phantom head 10) and provides the necessary mechanical environment for the medical procedure or treatment to be performed. For example, a surgeon / dentist can place his / her hands on the phantom jaw / teeth / head 10, 13, 14, 22 during surgery and thereby position his / her hands in the same manner as when treating a real patient.

[0175] The speed of the handpiece 30 is adjusted in response to the force applied by the user to the first handpiece 30 and the interaction of the virtual drill 30' with the virtual teeth of the virtual model of the jaw having the teeth 29. The virtual environment includes an algorithm for determining how the speed of the virtual drill 30' should change in response to the sum of the x, y, and z forces applied by the user on the first handpiece 30 (from the 3DOF sensor 50) and any reaction forces from the virtual contact of the virtual drill or handpiece 30' with the virtual teeth. The virtual environment uses Newtonian physics (i.e., force = spring constant × deflection) in some aspects to simulate the reaction forces between the virtual drill 30' and the virtual teeth, while using a PID control loop to determine the change in speed of the handpiece 30. The virtual teeth are assigned a hardness and stiffness. The stiffness is related to the spring constant provided by the tooth when in contact, and the hardness is related to the amount of work the virtual drill must perform to drill away the volume of the virtual teeth. The position of the real drill (first handpiece) 30 is used to determine whether contact is made with the virtual teeth.

[0176] Once the virtual environment calculates the virtual force acting on the virtual drill 30', it commands that force to a PID control loop that controls the velocity of an actuator in the system (described in further detail below) to change the real-world velocity of the first handpiece 30. The user senses the movement of the first handpiece 30. While the velocity of the first handpiece 30 is controlled by the dental surgery simulator 1, the direction of the first handpiece 30 is controlled by the user. The system measures the direction of the first handpiece 30 controlled by the user and, in response, updates the direction of the virtual drill 30' in the virtual environment. The computer 80 is also configured to update the position of the virtual drill 30' in the virtual environment.

[0177] The movably suspended phantom head 10 is used to adjust the orientation of the virtual environment displayed on the display 9. The orientation of the phantom head 10 can be adjusted manually, and the orientation of the virtual model is adjusted accordingly using a sensor (not shown) coupled to the computer 80 that measures the rotation of the phantom head 10. Thus, the phantom head 10 and the phantom jaw are co-located and connected to the virtual phantom head and virtual jaw. When the user turns the phantom head 10, the virtual head rotates in the scene, and when the user changes the degree of opening of the jaw, the virtual jaw adjusts its position in the virtual environment accordingly. The phantom head 10 is an intuitive control for the orientation of the virtual model.

[0178] The computer 80 provides an interface for the user to select different virtual environment surgeries and treatments to be simulated and to run various training software application surgeries. The training application monitors the user's interaction with the virtual environment and the first handpiece 30 and measures various criteria to evaluate the user's performance.

[0179] Now special reference Figures 4 to 7 The visual housing 6 is provided with a display screen 9 arranged toward the rear of the display housing 6. A viewing opening or window 8 in the upper side of the display housing 6, toward the front end of the display housing 6, allows the user to view the partially transparent reflective element 7 from the viewing area V. The partially transparent reflective element 7 is provided on the lower side of the display housing 6, toward the front end of the display housing 6, and allows the user to see the workspace W from the viewing area V through the partially transparent reflective element 7. The partially transparent reflective element 7 is arranged to reflect the image displayed on the display screen 9 toward the user's eyes, and the workspace W can be simultaneously visible to the user through the partially transparent reflective element 7 (assuming that the user's eyes are located in the viewing area V and the user is looking at the partially transparent reflective element 7). Therefore, from the user's perspective, the virtual image of the virtual environment is mixed with the real image of the workspace W.

[0180] The display screen 9 and partially transparent reflective element 7 are positioned so that the view is co-located with the position of the first handpiece 30. This allows the system to generate images of the virtual drill 30' that are aligned with the real world first handpiece 30 in the user's line of sight.

[0181] The dental surgery simulator is configured to reflect images from the display screen 9 to the user's eyes by reflection on the partially transparent reflective element 7 and to mix images of the virtual environment with the user's view of the workspace W through the partially transparent reflective element 7 .

[0182] Thus, the image on the display screen 9 is reflected to the user's eyes, and when the user views the semi-reflective element 7 from the viewing space V, the working space W is simultaneously visible to the user through the partially transparent reflective element 7 .

[0183] In an embodiment, the display screen 9 is a stereoscopic display screen, and the computer 80 is configured to send stereoscopic images to the stereoscopic display screen 9. In an embodiment, the stereoscopic display screen 9 is an autostereoscopic display screen 9. In an embodiment, the display screen 9 is a stereoscopic display screen, wherein the stereo level is adjustable so that it can be adjusted to the optimal level for a particular user.

[0184] The computer 80 is configured to provide a three-dimensional virtual environment including a first virtual tool 30' having a first virtual position and a first virtual orientation, the first virtual tool 30' corresponding in size and shape to the handpiece 30, and the first virtual tool 30' being co-located with the handpiece 30. A virtual drill 99 and at least one virtual tooth are displayed as part of the three-dimensional virtual environment. Figure 7 In the example of , the complete virtual lower jaw 29 is displayed. In an embodiment, both the virtual lower jaw 29 and the virtual upper jaw are displayed.

[0185] The computer 80 transmits an image of the simulated dental surgery or treatment to the display screen 9. The image on the display screen is reflected to the user's eyes by a translucent reflective element 7 (such as a translucent mirror, for example) (assuming that the user's eyes are located in a visual space V and the user is facing the translucent reflective element 7). The visual space is a three-dimensional space in which the user can simultaneously observe the image from the display screen 9 through the reflection of the translucent reflective element 7 and the objects in the work space W through the translucent reflective element 7.

[0186] The software is configured to present a virtual environment comprising at least one virtual object, such as a virtual tooth, all viewed by the user through the partially transparent reflective element 7. The virtual environment comprises a virtual tool, in this embodiment a virtual dental drill 30' corresponding to a real world tactile drill handle 30.

[0187] In an embodiment, the dental surgery simulator 1 is provided with adjustable lighting (not shown) over the workspace W. In an embodiment, the lighting is mounted to the underside of the display housing 6 and directed toward the workspace W. The adjustable lighting facilitates producing an appropriate balance for a given user between the image of the workspace W as seen through the partially transparent reflective element 7 and the image of the virtual environment reflected from the pressure-transparent reflective element 7.

[0188] Now special reference Figures 8 to 22 The upper jaw 13 and the lower jaw 14 are supported by the structure of the dental surgery simulator 1 and arranged in the workspace W. The lower jaw 14 is arranged to be movable (manually) relative to the upper jaw 13. The lower jaw 14 is suspended from the upper jaw 13 by a hinge mechanism 15 (a four-bar kinematic chain in this embodiment). Preferably, the hinge mechanism 15 simulates the movement of a human jaw to make the model realistic.

[0189] The model lower jaw 14 is suspended from the model upper jaw 13 to allow (manually imparted) Figure 19 and 20 The position sensor (not shown) is configured to generate a signal indicative of the position of the phantom mandible 14 relative to the phantom maxilla 13 and is connected to the computer 80. The software is configured to adjust the position of the virtual mandible based on the signal from the sensor.

[0190] The closed position of the phantom jaw 14 corresponds to the position for checking reduced bite. The software is configured to display a virtual upper set of teeth for the virtual upper jaw and a virtual lower set of teeth for the virtual lower jaw on the display screen 9, thereby allowing an occlusal check of the virtual sets of teeth.

[0191] The model upper jaw 13 is suspended from a support structure to allow rotation in three degrees of freedom, with the center of rotation of each degree of freedom located between the model upper jaw 13 and the model lower jaw 14, i.e., at the center of the workspace W, so that the model upper jaw 13 does not leave the workspace W before it is rotated. The X, Y, and Z rotation axes are as follows: Figure 16 The rotation is manually imparted and preferably coincides with the phantom head 10. Three rotational position sensors (not shown) for sensing the rotation of the upper jaw 13 are provided to sense rotation in each of the three degrees of freedom. The computer 80 receives signals from the three rotational position sensors. The software is configured to adjust the simulation of the dental procedure or treatment based on the signals from the rotational position sensors. Specifically, the software adjusts the orientation and position of the virtual upper jaw and the orientation and position of the virtual lower jaw.

[0192] The phantom upper jaw 13 is suspended from the support structure by a first mechanism 11 that allows the upper jaw to rotate about a first horizontal axis Y extending through the center of the workspace W without intersecting the workspace W. The mechanism includes a remote center linkage 11, preferably two spaced-apart parallel remote center linkages 11 to make the mounting structure of the phantom head 10 more rigid and stable. The linkage 11 is connected to the main housing 4 by a bracket 17.

[0193] The phantom upper jaw 13 is suspended from the support structure by a second mechanism that allows the phantom upper jaw 13 to rotate about a second horizontal axis X disposed in the workspace W, while the second mechanism does not intersect the workspace W. The second mechanism includes an L-shaped plate 12 extending between the phantom head 10 and the phantom upper jaw 13. The phantom upper jaw 13 is connected via the L-shaped plate 12 by a hinge pin (not visible in the figure) that allows the phantom upper jaw 13 and the phantom head 10 to rotate in unison about the second horizontal axis X.

[0194] The phantom upper jaw 13 is suspended from the support structure by a third mechanism 16 that allows the phantom upper jaw 13 to rotate about a vertical axis Z extending through the center of the workspace W, while the third mechanism 16 does not intersect the workspace W. The third mechanism 16 includes a hinge pin that connects the first mechanism 11 to the L-shaped plate 12 and allows the L-shaped plate 12 to rotate about the vertical Z axis.

[0195] The phantom upper jaw 13 comprises an upper support member 19 having removably attached thereto removable phantom upper jaw elements 21, 25, and the phantom lower jaw 14 comprises a lower support member 18 having removably attached thereto removably attached thereto removably phantom lower jaw elements 20, 24. In an embodiment, the removable phantom jaw elements 20, 21, 24, 25 are releasably attached to the upper or lower support elements 18, 19 by magnetic forces from a combination of permanent magnets and magnetic material members associated with the support and phantom jaw elements, respectively.

[0196] The universal model upper jaw component 25 and the universal model lower jaw component 24 do not have model teeth, but are still considered to constitute the model upper jaw and model lower jaw, respectively. Therefore, the model lower jaw or model upper jaw can be formed by a simple U-shaped member that is generally similar in shape and size to a human lower jaw or upper jaw, preferably an average human lower jaw or upper jaw, but without teeth and without recesses for receiving teeth. The universal model upper jaw and lower jaw can be made of a polymer material, such as plastic, natural and / or synthetic rubber.

[0197] The specific mold upper jaw element 20 and the specific mandibular element 21 are provided with mold teeth 22. The mold teeth 22 are detachably attached by inserting the mold teeth 22 into specific recesses 23 in the specific mold upper or mandibular element 20, 21. In an embodiment, the specific upper and mandibular elements 20, 21 with their mold teeth 22 are accurate models of a part of a real human upper and lower jaw with its upper teeth. One or more mold teeth 22 to be subjected to a dental operation or treatment are removed in order to provide space for the first handpiece 30 to move without being hindered by the associated mold teeth 22. In Figures 8 to 11 In the example, one model tooth 22 has been removed and the recess 23 in the associated model tooth 20, 21 is empty. The user can use the remaining model tooth 22 to support the user's hand and / or fingers. The virtual tooth will be displayed, connected, and co-located with the empty position / recess of the associated tooth in the (upper or lower) model jaw 13, 14 (or the specific mandibular element 20 / specific upper jaw element 21). Since the computer 80 is informed of the orientation and position of the corresponding upper and lower model jaws 13, 14 via sensors, the computer 80 adjusts the position and orientation of the virtual teeth accordingly, and in an embodiment, also adjusts the position and orientation of the virtual jaw in the virtual model accordingly.

[0198] When using specific upper and / or lower model jaw elements 20, 21, the computer 80 is provided with a virtual model of the specific lower jaw element 20 and / or the specific upper jaw element 21. Such a virtual model may include a virtual model of all teeth of the relevant jaw or only of one or more teeth corresponding to positions / recesses in the corresponding model jaw for which no model teeth 22 are provided.

[0199] The computer 80 is configured to display a virtual environment on the display screen 9 , the virtual environment including at least one virtual tooth co-located with the phantom upper jaw 13 or the phantom lower jaw 14 .

[0200] The model upper jaw 13 and the model lower jaw 14, 20 are movable relative to the support structure. The computer 80 receives the position and orientation of the model upper jaw 13, 21 and the model lower jaw 14, 20 via one or more sensors, and the computer 80 is configured to adjust the orientation and position of at least one virtual tooth according to the movement of the model upper jaw 13, 21 or the model lower jaw 14, 20, so that when the model upper jaw 13, 21 or the model lower jaw 14, 20 moves, the at least one virtual tooth remains co-located with the model upper jaw 13, 21 or the model lower jaw 14, 20 on the display screen 9.

[0201] In an embodiment, the computer 80 is configured to display at least a portion of the virtual upper jaw and a portion of the virtual lower jaw 29, and the computer is configured to co-position the virtual upper jaw with the phantom upper jaw 13 and the virtual lower jaw 29 with the phantom lower jaw 14 on the display screen 9, even when the phantom upper jaw 13, 21 or the phantom lower jaw 14, 20 is moved relative to the support structure.

[0202] In an embodiment, the computer 80 is configured to co-locate the virtual teeth with the phantom upper jaw 13, 21 or the phantom lower jaw 14, 20. Thus, the computer co-locates the virtual teeth with the phantom jaw 13, 14 regardless of any movement the user may apply to the phantom jaw 13, 14.

[0203] In an embodiment, the computer 80 is configured to display more than one virtual tooth and to co-locate the virtual teeth with the corresponding upper or lower mold jaw 13 , 14 .

[0204] The computer 80 instructs the user on which jaw element (universal or specific) to install for a given exercise. Thus, the computer 80 is configured to instruct the user on installing a universal upper or lower jaw element 25, 24 or specifically a specific upper or lower jaw element 20, 21.

[0205] exist Figures 12 to 21In the embodiment shown in FIG, the phantom upper jaw 13 and the phantom lower jaw 14 are part of the phantom head 10. The phantom head 10 and its phantom lower jaw 14 and phantom upper jaw 13 are arranged to be movable relative to the support structure of the dental surgery simulator 1 and the phantom head 10, and its phantom lower jaw 14 and phantom upper jaw 13 move in unison with each other.

[0206] Figure 37 and 38 An embodiment of a segmented upper jaw 22 is shown. In this embodiment, the upper jaw 21 and / or the lower jaw 20 are segmented jaws, wherein at least one segment is removable. In the embodiment shown, the segmented jaw has five segments 21a, 21b, 21c, 21d, and 21e. Preferably, at least one segment is removable. Figure 38 The phantom jaw is shown with the central segment 21c removed. In an embodiment, all segments are removable, i.e., they can be removed without the use of tools and reinstalled without the use of tools. The segments can slide into guides, attach magnetically, attach using Velcro or other suitable releasable attachment means.

[0207] By using a segmented phantom jaw, in which at least one or more or all segments can be removed, abutments between the haptic arm and the phantom jaw can be avoided, which can occur particularly when simulating activities involving treatment of virtual teeth associated with the mandible. In other words, in some cases, a portion of the phantom jaw obstructs the haptic arm, in particular the handpiece coupling 31, and by removing the relevant segmented phantom jaw segment 21a, 21b, 21c, 21d or 21e, a space is left for the haptic arm, while the majority of the phantom jaw remains for the user to use as a hand support and to provide realism for the simulation.

[0208] Now special reference Figures 23 to 26 , which illustrates a linkage 40 controlled by a computer 80 to simulate a medical procedure or treatment. The linkage 40 includes a main coupling 41 (which is an elongated straight member in an embodiment), and a first handpiece 30 is connected to the front end of the main coupling 41 via a mechanical joint having at least two degrees of freedom, as will be explained in more detail below. The linkage 40 has a first crank 42 driven by a first rotary actuator 47, a second crank 44 driven by a second rotary actuator 48, and a third crank 46 driven by a third rotary actuator 49. The respective rotational axes of the first, second, and third cranks 42, 44, 46 can be arranged orthogonally relative to each other in an embodiment (not shown).

[0209] The rotation axis of the first crank 42 extends substantially vertically. The first crank 42 is directly coupled to the main coupling 41 at a first position at or near the rear end of the main coupling 41 (ie, without an intermediate coupling therebetween) via a hinge with two degrees of freedom, such as a universal joint.

[0210] A second crank 44 is coupled directly (i.e., without an intermediate coupling) to the main coupling 41 via a first horizontally extending connecting rod 43, preferably via a universal joint allowing rotation about two axes, and a third crank 46 is coupled to the main coupling 41 via a second vertically extending connecting rod 45. The first crank 42 is arranged to actuate the main coupling 41 in a first (horizontal) axial direction X. The second crank 44 is arranged to actuate the main coupling 41 in a second (horizontal) transverse direction Y, and the third crank 46 is arranged to actuate the main coupling 41 in a second (vertical) transverse direction Z.

[0211] The first link 43 is coupled to the main coupling 41 at a second axial position between the front end and the first position, and the second link 45 is coupled to the main coupling 41 at a third axial position between the front end and the first position. In an embodiment, the second and third axial positions substantially coincide.

[0212] The main coupling 41 includes a three-dimensional force sensor (3DOF sensor) 50 for sensing the force applied by the user to the first handpiece 30 in three dimensions. The 3D force sensor 50 is disposed between the front end position and the second and / or third axial positions and is preferably an integral part of the main coupling 41. The 3D force sensor 50 is coupled (data-connected) to the computer 80, for example, via a signal cable.

[0213] The first, second, and third cranks 42, 44, 46 are coupled (directly or to a rotary motor driving the respective cranks) to respective first, second, and third rotary position sensors or encoders 26, 27, 28 that are data-connected to the computer 80. In the illustrated embodiment, the axes of rotation of the second crank 44 and the third crank 46 both extend horizontally and parallel to each other. However, the axes of rotation of the second crank 44 and the third crank 46 of the primary embodiment also extend horizontally and at an angle, for example, a right angle, to each other.

[0214] The first, second, and third cranks 42, 44, 46 are mounted on a reference member 51 (e.g., a frame or base). The reference member 51 is supported by the main housing 4 or by a support structure of the dental surgery simulator 1. The linkage 40 connects the handpiece 30 to the reference member 51 and provides the handpiece 30 with six independent degrees of freedom relative to the reference member 51.

[0215] The handpiece support 32 provides a parking position for the first handpiece 30 when the first handpiece 30 is not in use. A parking sensor 59 is associated with the handpiece support 32 to detect the parking position of the first handpiece 30.

[0216] The arrangement of the linkage 40 creates a workspace W in which the first handpiece 30 can be manipulated by a user, which is shaped as a rectangular parallelepiped with horizontal top and bottom.

[0217] Now special reference Figures 27 to 29 , which illustrates the first hand piece 30 in more detail. The first hand piece 30 includes an inner portion 38 extending to an outer portion 37, the outer portion being configured to rotate about the inner portion 38. The outer portion 37 forms a housing for the first hand piece 30 and is configured to rotate about the inner portion 38 about the longitudinal axis L of the hand piece 30. A portion 57 of the inner portion 38 protrudes from the outer portion 37 and is coupled to the front end of the linkage 40 by a joint having at least two degrees of freedom. The joint includes a hand piece coupling 31 coupled to the inner portion 38 at one of its ends by a first pivot hinge 34 to provide one degree of freedom. The other end of the hand piece coupling 31 is attached to a connecting element 56 by a first pivot joint 36 to provide a second degree of freedom. The connecting element 56 is rigidly connected to the end of the main coupling 41.

[0218] A first inertial measurement unit 52 is mounted to the inner portion 38. A fourth rotational position sensor 53 senses rotational movement of the outer portion 37 relative to the inner portion 38. The fourth rotational position sensor 53 is mounted on the inner portion 38 and is arranged to measure the rotational position of the outer portion 37 relative to the inner portion 38. At least a first portion of the fourth rotational position sensor 53 is mounted on the inner portion 38, and the first portion is connected to the computer 80 via a cable 58 guided or supported by the inner portion 38.

[0219] The first inertial measurement unit 52 and the fourth rotational position sensor 53 are coupled to the computer 80 by a cable 58, which is received in a cable channel 35 extending through the interior portion 38. The cable 58 exits the interior portion 38 near the first hinge 34 and then enters the cable channel 33 extending through the handpiece coupling 31. The cable 58 establishes a data connection between the inertial measurement unit 52 and the computer 80 to transmit position and / or orientation data, and establishes a data connection between the fourth rotational position sensor 54 and the computer 80 to transmit rotational position data.

[0220] The cap 39 forms the free end of the first handpiece 30. A first rotary bearing 54 and an axially spaced second rotary bearing 55 are arranged between the inner portion 38 and the outer portion 37. The outer portion 37 has unrestricted rolling relative to the inner portion 38 due to the absence of a restricting structure.

[0221] Inner portion 38 is elongated and is connected to handpiece coupling 31 at a first end of inner portion 38. A fourth rotational position sensor 53 is disposed at or near a second end of inner portion 38, which is located inside outer portion 37.

[0222] The longitudinal extent of the outer portion 37 includes a proximal portion (closer to the user) and a distal portion (away from the user). The distal portion extends at an angle to the proximal portion, and the inner portion 38 protrudes from the outer portion 37 through the distal portion.

[0223] The first inertial measurement unit 52 is positioned within the housing 37 of the handpiece 30 and mounted on the interior portion 38. The first inertial measurement unit 52 is configured to measure translational acceleration, rotational velocity, and magnetic fields. Thus, the first inertial measurement unit 52 is also capable of determining the velocity and displacement of the first handpiece 30 using data processing techniques known in the art. In an embodiment, the first inertial measurement unit 52 has nine sensors, including a three-axis gyroscope, a three-axis accelerometer, and a three-axis magnetometer. The first inertial measurement unit 52 is provided with an embedded digital motion processor that acquires and processes data from the accelerometer, gyroscope, and magnetometer. The inertial measurement unit chip outputs a quaternion, which describes an orientation in space relative to a reference, such as in real space. This data output, along with a signal from the fourth rotational position sensor 53, is transmitted along a cable 58 to a computer 80.

[0224] The inertial measurement unit 52 is calibrated before use by placing the handpiece 30 in a defined orientation so that the environmental reference is aligned. Figure 28 The handpiece holder 32 is shown in its parked position for calibration.

[0225] Now special reference Figures 30 to 33 , which illustrates another embodiment of a dental surgery simulator 1. In this embodiment, for simplicity, structures and features that are the same as or similar to corresponding structures and features previously described or illustrated herein are denoted by the same reference numerals as previously used.

[0226] In this embodiment, an auxiliary tool 60 having a second handpiece 61 is added, for example, to simulate a mirror tool used by a dentist. Unlike the first handpiece 30, whose real-world position is controlled by the dental surgery simulator 1, the real-world position of the second handpiece 61 is controlled by the user (the auxiliary tool 60 is not actuated and is moved manually without tactile feedback). The auxiliary tool 60 is suspended from the support arm 5 and includes a second handpiece 61 that the user can manipulate in the workspace W. The auxiliary tool 60 is suspended from the main structure of the dental surgery simulator via a linkage. The computer 80 is configured to display a corresponding virtual auxiliary tool in the virtual environment, such as a virtual dental mirror corresponding to the handle of a real-world dental mirror. The position and movement of the virtual second handpiece are adjusted to directly match the real-world position of the second handpiece 61.

[0227] The auxiliary tool 60 includes a main coupling 63 coupled to the structure of the dental surgery simulator 1 by one or more joints providing a first and a second degree of freedom, and a secondary coupling 66 coupled to the main coupling 63 by one or more joints providing a third and a fourth degree of freedom. The second handpiece 61 is connected to the secondary coupling 66 by one or more joints providing a fifth and a sixth degree of freedom to form a serial chain connecting the handpiece 61 to the main structure of the dental surgery simulator 1 with six degrees of freedom. The fifth rotational position sensor 68 senses movement in the first degree of freedom, the sixth rotational position sensor 72 is used to sense movement in the second degree of freedom, and the seventh rotational position sensor 73 is used to sense movement in the third degree of freedom. The fifth, sixth and seventh position sensors 68, 72, 73 are data-connected to the computer 80,

[0228] The second inertial measurement unit 74 is disposed in the second handpiece 61 and moves in unison with the second handpiece 61. The second inertial measurement unit 74 is data-connected to the computer 80 and is configured to sense motion in at least the fourth, fifth, and sixth degrees of freedom. In an embodiment, the second inertial measurement unit 74 is technologically identical to the first inertial measurement unit 52.

[0229] The second hand piece 61 is connected to the secondary linkage 66 by a fourth pivot joint 69 providing a sixth degree of freedom. The sixth degree of freedom allows the second hand piece 61 to rotate about the (longitudinal) axis of the second hand piece 61. The second inertial measurement unit 74 is configured to sense the sixth degree of freedom.

[0230] The fourth pivot joint 69 is connected to the end of the secondary link by a second hinge 62 which provides a fifth degree of freedom to the second hand piece 61 .

[0231] The second handpiece 61 can move in three translational degrees of freedom, and the second handpiece 61 itself can move in three rotational degrees of freedom.

[0232] The main coupling 63 is an elongated coupling such as a rod or a tube. The main coupling 63 is coupled to a reference member (e.g., a support structure of the dental surgery simulator 1) via a fourth hinge 75, which allows the main coupling 63 to rotate about a transverse axis (transverse to the longitudinal extent of the main coupling 63) to obtain a second degree of freedom.

[0233] The main link 63 is coupled to the fourth hinge 75 by a third pivot joint 67 which allows the main link 63 to rotate about its longitudinal axis to achieve a first degree of freedom.

[0234] The fifth rotational position sensor 68 is arranged to sense rotation about the longitudinal axis of the main coupling 63 , and the second rotational position sensor 72 is arranged to sense rotation about the third hinge 75 .

[0235] The secondary link 66 is an elongated link that is coupled to the primary link 63 by a third hinge 65 that allows the secondary link 66 to rotate about a transverse axis (transverse to the longitudinal axis of the secondary link 66) to obtain a third degree of freedom.

[0236] The seventh rotational position sensor 73 is configured to sense rotational movement of the secondary link 66 about the third hinge 65. The secondary link 66 is coupled to the third hinge 65 by a second pivot joint 64 that allows the secondary link 66 to rotate about its longitudinal axis to obtain a fourth degree of freedom.

[0237] The tertiary link 70 is coupled to the quaternary link 71. The tertiary link 70 is coupled to the primary link 63 or the secondary link 66, and the quaternary link 71 is coupled to the seventh rotational position sensor 73 to form a serial chain that converts the rotation of the secondary link 66 about its transverse axis (about the third hinge 65) into a rotational movement of the seventh rotational position sensor 73.

[0238] The second inertial measurement unit 74 is configured to sense rotation of the handpiece 61 about the (longitudinal) axis of the handpiece 61, ie, to sense motion in a sixth degree of freedom. The second inertial measurement unit 74 is in data communication with the computer 80, preferably via a wireless (RF) data connection.

[0239] In an embodiment (not shown), a rotational position sensor is arranged within the second handpiece 61 for sensing rotation of the handpiece 61 about the longitudinal axis of the handpiece 61 .

[0240] In an embodiment, the second inertial measurement unit 74 is configured to sense motion in all six degrees of freedom, and the computer 80 is configured to calibrate the inertial second measurement unit 74 using signals from the fifth, sixth, and / or seventh sensors 68 , 72 , 73 as a reference.

[0241] Typically, the computer 80 is configured to: receive information indicative of the rotational position of the first, second, and third cranks, and control actuation of the first, second, and third cranks (global linear motion of the first hand piece 30), to receive information indicative of actuation of the first hand piece 30 and the second hand piece 61, and to receive information indicative of the orientation (rotational position) of the first hand piece 30 from the first inertial measurement unit 52, and to receive information indicative of the orientation (rotational position) of the second hand piece 61 from the second inertial measurement unit 74. A control scheme is used in which the position, orientation, and actuation of the first hand piece 30 are sensed by the computer 80, which is also capable of providing tactile feedback to the first hand piece 30 via the actuators 47, 48, 49, as determined by the characteristics of the virtual model. The position of the virtual tool in the virtual environment is displayed on the display screen 9.

[0242] By using data from the rotational position sensors 26, 27, 28, 68, 72, 73 associated with the first linkage 40 and the second linkage 60 and from the first and second inertial measurement units 52, 74 and the rotational position sensor 53, the position and orientation of the virtual tool in the virtual environment are displayed on the display screen 9 so as to be co-located with the position and orientation of the real tool.

[0243] In an embodiment, the computer 80 is configured to simulate a medical procedure or treatment by utilizing tactile feedback, preferably tactile force feedback, of the linkage 40 and its associated actuators 47, 48, 49, and by utilizing visual feedback on the display screen 9. To this end, the computer 80 is configured to use the signal from the three-dimensional force sensor 50 as input and control the position of the end of the linkage 40 accordingly.

[0244] In an embodiment, the computer 80 includes software applications for providing a training platform, providing instructional materials and videos, recording, playback, and evaluation of user performance; providing audio, video, and text communication with a remote instructor over a computer network; providing the ability for the remote instructor to provide force input to the haptic system; and providing different virtual objects (e.g., teeth, jaws, or a complete head), tools, and physics rules to the virtual environment.

[0245] In an embodiment, the computer 80 is configured to detect collisions between the drill bits of the virtual dental drill (using the real position of the first tool 30) to determine an interaction force to be applied to the virtual drill based on the virtual drill position, the virtual drill model, and the virtual tooth model. The computer 80 is also configured to calculate a virtual drill speed based on the interaction force and user input (such as from a foot pedal).

[0246] In an embodiment, the tooth model volume is represented as a set of three-dimensional pixels or voxels. Each voxel has a hardness value associated with it, representing the type / quality of the tooth material (i.e., dentin, enamel, pulp). A conventional marching cube algorithm is used to generate a triangular mesh of the isosurface of the tooth model voxel set.

[0247] The virtual handpiece is modeled analytically or using voxels. Therefore, the physical model of the handpiece is either a finite number of voxels or a fully analytically defined shape. The handpiece model also includes vector parameters for the handpiece's three-dimensional velocity. The virtual tool includes a virtual drill. The virtual drill or virtual handpiece can be in virtual contact with a virtual tooth. The shape of the virtual drill is rendered for the voxels of the virtual tooth. The real position of the first handpiece 30 is used to determine the position of the virtual drill and the contact between the virtual drill and the virtual tooth.

[0248] Now special reference Figure 35The force control loop is used to control the velocity in one direction at the end of the main coupling 41, and thereby the velocity of the first handpiece 30. A total of three of these force control loops are activated to control three directions of motion (3DOF). The force control loop uses the difference between the virtual force calculated by the virtual environment 90 and the actual force in one direction calculated from the force measured by the 3DOF force sensor 50 at summing point 86. The output at summing point 86 is the input to a lead-lag compensator 87, which removes high frequencies and is connected to a standard PI or PID controller 88. The PI or PID controller calculates the velocity command for a motor driver 89. The motor driver 89 also receives signals from the rotary position sensors (encoders) 26, 27, and 28 and determines the actual velocity of the handpiece 30 based on the position signals. The motor driver 89 electrically drives the first rotary actuator 47. (The motor drivers of the other two control loops drive the second and third rotary actuators 48 and 49.) The motor driver uses the difference between the speed command from the PI or PID controller and the actual speed calculated based on the actual position measured by the position sensors (encoders) 26, 27, 28 on the corresponding rotary actuators 46, 47, 48. A differentiator 92, receiving the position signal, provides the actual speed as an output signal. The output of differentiator 92 is provided to the motor driver 89 and the virtual environment 90. In an embodiment, differentiator 92 is an integral part of the motor driver 89. The first, second, and third rotary actuators 47, 48, 49 are connected to the first handpiece 30 via a linkage 40 connected to the various sensors (force, position, and direction) described above. Input from a foot pedal sensor 91 (connected to the dental surgery simulator 1 and to the computer 80 via a data cable) is used to determine the rotational speed of the virtual drill. The virtual environment receives signals from the IMU 52 to inform it of the orientation of the first handpiece 30. The virtual environment 90 includes a drill model, a tooth model, and a jaw model, and uses the real position and real orientation of the first handpiece 30 to determine the position and orientation of the virtual drill. The virtual drill model and the virtual tooth model or jaw model are used to calculate the resulting virtual forces, which are sent as commands to the return force control loop and applied to the handpiece 30 .

[0249] To begin using the dental surgery simulator 1, the user positions themselves on a chair (not shown) in front of the dental surgery simulator 1. If the display screen 9 is an autostereoscopic display, the user does not need to use shutter glasses or glasses with polarized lenses. The height of the main housing 4 is appropriately adjusted to the user's ideal working height. The chair height can also be adjusted according to the user's needs.

[0250] In an embodiment, the dental surgery simulator is provided with a network (eg, LAN, WAN) connection via the computer 80 .

[0251] Figure 36Another embodiment is shown in which the functionality of the dental surgery 1 simulator is enhanced by increasing the possibility of training the user by drilling into plastic teeth using a conventional dental handpiece 130 including a motor-driven drill. In this embodiment, at least the upper or lower mold jaw is provided with one or more mold teeth 22 made of polymer (plastic) material suitable for drilling with a dental drill. The mold teeth 22 are detachably attached by inserting the mold teeth 22 into specific recesses 23 in the specific mold upper or lower jaw element 20, 21. Thus, the polymer material teeth 22 can be replaced after they have been drilled in, or they can be replaced in order to provide another practice with different teeth 22. In this embodiment, the specific upper and lower jaw elements 20, 21 with their mold teeth 22 are preferably accurate models of a part of a real human upper and lower jaw with its teeth made of a suitable polymer (plastic) material. The mold teeth 22 to be subjected to dental surgery or treatment are drilled into by using a conventional dental handpiece 130 to train (aspiring) dentists. The conventional dental handpiece 130 is powered (electrically or pneumatically) via a cable 133 that connects the conventional dental handpiece 130 to the main housing 4 for powering a pneumatic or electric motor in the conventional dental handpiece 130. The pneumatic or electric motor drives a dental drill (not shown) for drilling into the plastic tooth 22. The cable 133 also provides pressurized water to the conventional dental handpiece 130 for spraying water onto the workspace.

[0252] In a variation of this embodiment, the device 1 is configured to operate in another mode when the user is drilling into a plastic tooth using a conventional dental handpiece 130. Thus, the computer 80 runs a specific training program suitable for training by drilling into a plastic tooth 22 using a conventional dental handpiece 130.

[0253] The computer 80 can be programmed to enhance the user experience when drilling into a plastic tooth 22 using a conventional dental handpiece 130 through graphics on the display screen 9 and / or through audio information via the speakers. Thus, the training experience can be enhanced by providing instructions or feedback about the user's performance on the display screen 9 or through the speakers.

[0254] The computer 80 has at least a first mode of operation for simulating a dental procedure or treatment using the handpiece 30 and a second mode of operation for training a dental procedure or treatment using the conventional powered dental handpiece 130 .

[0255] Throughout this disclosure, any reference to a body part, such as teeth, jaw, maxilla, or head, generally refers to a human version of that body part. Thus, throughout this disclosure, for example, a phantom jaw is a physical model of a human jaw, and for example, a virtual jaw is a virtual model of a human jaw. The degree of similarity between the phantom body part and the real body part is preferably such that at least the shape of the phantom body part closely resembles the shape of the real body part, to the extent that the phantom body part provides a user with a realistic impression of the body part.

[0256] Various aspects and implementations have been described in conjunction with various implementations herein. However, other variations to the disclosed embodiments may be understood and implemented by those skilled in the art in practicing the claimed subject matter, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article does not exclude a plurality. A single processor or other unit may perform the functions of several items recited in a claim. The fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. The computer program may be stored / distributed on a suitable medium, such as an optical storage medium or solid-state medium provided with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunications systems.

[0257] Reference numerals used in the claims should not be construed as limiting the scope. Unless otherwise indicated, the drawings are intended to be read together with the specification (e.g., cross-hatching, arrangement of parts, proportions, extent, etc.) and are to be considered part of the entire written description of the present disclosure. As used in the description, the terms "horizontal," "vertical," "left," "right," "upper," and "lower," and their adjective and adverb derivatives (e.g., "horizontally," "to the right," "upward," etc.), refer only to the orientation of the illustrated structures when a particular drawing is facing the reader. Similarly, the terms "inwardly" and "outwardly" generally refer to the orientation of a surface relative to its axis of elongation or axis of rotation, as the case may be.

Claims

1. A dental surgery simulator comprising: Support structure for display housing and parallel robot, a display screen provided in the display housing, A computer configured to simulate a dental procedure or treatment, A parallel robot controlled by the computer, The parallel robot provides at least three translational degrees of freedom, the parallel robot being controlled by the computer to simulate dental surgery or treatment by providing tactile force feedback via the parallel robot, a handpiece operatively coupled to the parallel robot via a mechanism providing at least three rotational degrees of freedom, The handpiece is configured to be held in a hand of a user and manipulated by the user in a workspace in real space, The computer is configured to generate an image of the simulated dental procedure for display on a display screen, a partially transparent reflective element provided in the display housing, the reflective element being arranged to reflect an image from the display screen toward an eye of the user, The workspace is arranged to be visible to the user through the partially transparent reflective element.

2. The dental surgery simulator according to claim 1, wherein: The parallel robot includes one actuator for each translational degree of freedom.

3. A dental surgery simulator according to claim 1 or 2, comprising a sensor for sensing the orientation of the handpiece.

4. A dental surgery simulator according to any one of claims 1 to 3, configured to reflect the image from the display screen to the user's eyes by reflection on the partially transparent reflective element, and configured to mix the image with the view of the workspace seen by the user through the partially transparent reflective element.

5. The dental surgery simulator according to any one of claims 1 to 4, wherein: The image on the display screen is reflected toward the user's eyes, and wherein the workspace is simultaneously visible to the user through the partially transparent reflective element when the user looks at the partially transparent reflective element from a viewing space.

6. The dental surgery simulator according to any one of claims 1 to 5, wherein: The display screen is a stereoscopic display screen, preferably an autostereoscopic display screen.

7. The dental surgery simulator according to claim 6, wherein: The computer is configured to send a stereoscopic image to the stereoscopic display screen.

8. The dental surgery simulator according to any one of claims 1 to 7, wherein: The computer is configured to generate an image of a virtual handpiece co-located with the handpiece, the image preferably being a stereoscopic image.

9. The dental surgery simulator according to any one of claims 1 to 8, wherein: The computer is configured to provide a three-dimensional virtual environment including a first virtual tool having a first virtual position and a first virtual orientation, the first virtual tool corresponding in size and shape to the handpiece and the first virtual tool being co-located with the handpiece.

10. The dental surgery simulator according to any one of claims 1 to 9, wherein: The partially transparent reflective element is a partially transparent mirror or a semi-transparent mirror.

11. A dental surgery simulator comprising: A computer configured to simulate a dental procedure or treatment, A parallel robot controlled by the computer, The parallel robot provides at least three translational degrees of freedom, The parallel robot is controlled by the computer to simulate dental surgery or treatment by providing tactile force feedback through the parallel robot, a handpiece operatively coupled to the parallel robot via a mechanism providing at least three rotational degrees of freedom, The handpiece is configured to be held in a hand of a user and manipulated by the user in a workspace in real space, and Autostereoscopic display, The computer is configured to generate a stereoscopic image of a simulated dental procedure for display on the autostereoscopic display screen, and the computer is configured to generate a stereoscopic image of a virtual handpiece co-located with the handpiece.

12. The dental surgery simulator according to claim 11, comprising a parallel robot controlled by the computer, The parallel robot provides at least three translational degrees of freedom, The parallel robot is controlled by the computer to simulate dental surgery or treatment by providing tactile force feedback through the parallel robot, The handpiece is operably coupled to the parallel robot via a mechanism providing at least three rotational degrees of freedom.

13. The dental surgery simulator according to claim 12, wherein: The parallel robot includes one actuator for each translational degree of freedom.

14. A dental surgery simulator according to any one of claims 11 to 13, comprising a sensor for sensing the orientation of the handpiece.

15. A dental surgery simulator according to any one of claims 11 to 14, comprising a partially transparent reflective element arranged to reflect images from the autostereoscopic display screen to the user's eyes, The workspace is arranged to be visible to the user through the partially transparent reflective element.

16. The dental surgery simulator according to any one of claims 11 to 15, wherein: The computer is configured to generate a three-dimensional virtual environment including a first virtual tool having a first virtual position and a first virtual orientation, the first virtual tool preferably corresponding in size and shape to the handpiece, and the computer is configured to co-position the first virtual tool with the handpiece.

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