阅读说明：本技术 牙体预备系统 (Dental preparation system ) 是由 王利峰 孙贝 沈晨 刘洪澎 于 2021-01-26 设计创作，主要内容包括：本发明提供一种牙体预备系统,包括视觉标记导板、牙科机器人、视觉导航仪和预备控制装置；其中,视觉标记导板设置在待修复牙齿所在牙列上,视觉标记导板上设置有牙列视觉标记；牙科机器人包括机械定位臂,以及设置在机械定位臂末端的手术器械,手术器械上设置有器械视觉标记；视觉导航仪用于检测牙列视觉标记和器械视觉标记的位置姿态；预备控制装置基于牙列视觉标记的位置姿态进行视觉标定,基于器械视觉标记的位置姿态进行手眼标定,并基于视觉标定结果和手眼标定结果控制机械定位臂动作。本发明提供的系统,即便是口腔内狭小且非直视的环境,也能通过自动控制牙科机器人运动,使牙体预备的精度更高,同时提高操作效率和一致性。(The invention provides a tooth preparation system, which comprises a visual marking guide plate, a dental robot, a visual navigator and a preparation control device, wherein the visual marking guide plate is arranged on the dental robot; the visual marking guide plate is arranged on the dentition where the tooth to be restored is located, and dentition visual marks are arranged on the visual marking guide plate; the dental robot comprises a mechanical positioning arm and a surgical instrument arranged at the tail end of the mechanical positioning arm, wherein an instrument visual mark is arranged on the surgical instrument; the visual navigator is used for detecting the position and the posture of the dentition visual mark and the instrument visual mark; the preparation control device performs vision calibration based on the position posture of the dentition vision mark, performs hand-eye calibration based on the position posture of the instrument vision mark, and controls the mechanical positioning arm to act based on the vision calibration result and the hand-eye calibration result. The system provided by the invention can automatically control the motion of the dental robot even in a narrow and non-direct-viewing environment in the oral cavity, so that the tooth preparation precision is higher, and the operation efficiency and consistency are improved.)

1. A dental preparation system is characterized by comprising a visual marking guide plate, a dental robot, a visual navigator and a preparation control device;

the visual mark guide plate is arranged on the dentition where the tooth to be restored is located, and dentition visual marks are arranged on the visual mark guide plate;

the dental robot comprises a mechanical positioning arm and a surgical instrument arranged at the tail end of the mechanical positioning arm, wherein instrument visual marks are arranged on the surgical instrument;

the visual navigator is used for detecting the position and the posture of the dentition visual mark and the instrument visual mark;

the preparation control device performs vision calibration based on the position posture of the dentition vision mark, performs hand-eye calibration based on the position posture of the instrument vision mark, and controls the mechanical positioning arm to act based on the vision calibration result and the hand-eye calibration result.

2. The dental preparation system of claim 1, wherein the preparation control means comprises:

the visual calibration unit is used for performing visual calibration on the basis of the position postures of the dentition visual markers in a visual coordinate system and a virtual coordinate system;

the hand-eye calibration unit is used for performing hand-eye calibration based on the position postures of the instrument visual mark in a visual coordinate system and a robot coordinate system;

and the mechanical arm control unit is used for converting the virtual control information in the virtual coordinate system into the mechanical robot coordinate system based on the vision calibration result and the hand-eye calibration result to obtain machine control information so as to control the action of the mechanical positioning arm.

3. The dental preparation system of claim 2, wherein the visual calibration unit is configured to:

acquiring the relative position between the probe tool and the dentition visual mark when the probe tool touches a plurality of mark points on the dentition, wherein the tail end of the probe tool is provided with the visual mark;

and determining the vision calibration result based on the relative position of each mark point and the position of each mark point in the three-dimensional model of the dentition under the virtual coordinate system.

4. The dental preparation system of claim 2, wherein the robotic arm control unit is further configured to:

and planning a restoration path based on the three-dimensional model of the dentition and the restoration model to obtain a cutting path as the virtual control information, wherein the restoration model is constructed based on the three-dimensional model.

5. The dental preparation system of claim 2, wherein the dental robot further comprises a force sensor disposed at a distal end of the mechanical positioning arm;

the robot arm control unit is further configured to:

and determining the virtual control information based on the moment information fed back by the force sensor and the relative position information of the area to be cut in the dentition and the surgical instrument in the three-dimensional model.

6. The dental preparation system of claim 2, wherein the mechanical positioning arm comprises a plurality of positioning arms connected in series by a rotary joint, the rotary joint being provided with a servo torque motor;

the machine control information is used for controlling each servo torque motor.

7. The dental preparation system of claim 2, further comprising:

and the display equipment is used for converting the position postures of the dentition visual mark and the instrument visual mark in a visual coordinate system into the position postures in the virtual coordinate system based on the visual calibration result, and updating and displaying the position postures of the dentition and the three-dimensional model of the surgical instrument.

8. The dental preparation system of any one of claims 1 to 7, further comprising:

and the intraoral scanning equipment is used for intraoral scanning of the patient to obtain a three-dimensional model of the dentition where the tooth to be restored is located.

9. The dental preparation system of claim 8, further comprising:

and the guide plate generating unit is used for generating a guide plate based on the outline surface of the dentition in the three-dimensional model of the dentition, and the guide plate is fixedly connected with the dentition visual mark to form the visual mark guide plate.

10. The dental preparation system of claim 9, wherein the visual marker guide is fitted onto the dentition in a bone supporting manner.

Technical Field

The invention relates to the technical field of robots, in particular to a tooth preparation system.

Background

Tooth preparation refers to the technical operation of restoring, improving or reconstructing the anatomical appearance and physiological function of a defective or missing tooth, removing caries and finishing the appearance of the adjacent tooth of the affected tooth or the missing tooth through a dental instrument so as to meet the requirements of retention, support, appearance, beauty and function of a prosthesis.

The traditional tooth preparation operation is usually performed by a doctor holding a dental high-speed handpiece to complete the cutting and grinding of teeth. Due to the shaking hands and the narrow and non-direct-viewing operating space in the oral cavity, the shape accuracy of the prepared teeth depends on the clinical experience and technical level of doctors, and the consistency is difficult to ensure.

Therefore, a digital and intelligent device is needed to assist the doctor to quickly complete the dental preparation, and to improve the precision and work efficiency of the operation.

Disclosure of Invention

The invention provides a tooth preparation system, which is used for solving the defect that the preparation quality of teeth is difficult to guarantee due to hand shaking and non-direct vision of an oral operation environment in the prior art.

The invention provides a tooth preparation system, which comprises a visual marking guide plate, a dental robot, a visual navigator and a preparation control device, wherein the visual marking guide plate is arranged on the dental robot;

the visual mark guide plate is arranged on the dentition where the tooth to be restored is located, and dentition visual marks are arranged on the visual mark guide plate;

the dental robot comprises a mechanical positioning arm and a surgical instrument arranged at the tail end of the mechanical positioning arm, wherein instrument visual marks are arranged on the surgical instrument;

the visual navigator is used for detecting the position and the posture of the dentition visual mark and the instrument visual mark;

the preparation control device performs vision calibration based on the position posture of the dentition vision mark, performs hand-eye calibration based on the position posture of the instrument vision mark, and controls the mechanical positioning arm to act based on the vision calibration result and the hand-eye calibration result.

According to a dental preparation system provided by the present invention, the preparation control device includes:

the visual calibration unit is used for performing visual calibration on the basis of the position postures of the dentition visual markers in a visual coordinate system and a virtual coordinate system;

the hand-eye calibration unit is used for performing hand-eye calibration based on the position postures of the instrument visual mark in a visual coordinate system and a robot coordinate system;

and the mechanical arm control unit is used for converting the virtual control information in the virtual coordinate system into the mechanical robot coordinate system based on the vision calibration result and the hand-eye calibration result to obtain machine control information so as to control the action of the mechanical positioning arm.

According to the present invention, there is provided a dental preparation system, the vision calibration unit is configured to:

acquiring the relative position between the probe tool and the dentition visual mark when the probe tool touches a plurality of mark points on the dentition, wherein the tail end of the probe tool is provided with the visual mark;

and determining the vision calibration result based on the relative position of each mark point and the position of each mark point in the three-dimensional model of the dentition under the virtual coordinate system.

According to a dental preparation system provided by the present invention, the robot arm control unit is further configured to:

and planning a restoration path based on the three-dimensional model of the dentition and the restoration model to obtain a cutting path as the virtual control information, wherein the restoration model is constructed based on the three-dimensional model.

According to the invention, the dental robot further comprises a force sensor arranged at the end of the mechanical positioning arm;

the robot arm control unit is further configured to:

and determining the virtual control information based on the moment information fed back by the force sensor and the relative position information of the area to be cut in the dentition and the surgical instrument in the three-dimensional model.

According to the tooth preparation system provided by the invention, the mechanical positioning arm comprises a plurality of positioning arms which are connected in series through rotary joints, and a servo torque motor is arranged at the rotary joints;

the machine control information is used for controlling each servo torque motor.

According to the present invention, there is provided a dental preparation system, further comprising:

and the display equipment is used for converting the position postures of the dentition visual mark and the instrument visual mark in a visual coordinate system into the position postures in the virtual coordinate system based on the visual calibration result, and updating and displaying the position postures of the dentition and the three-dimensional model of the surgical instrument.

According to the present invention, there is provided a dental preparation system, further comprising:

and the intraoral scanning equipment is used for intraoral scanning of the patient to obtain a three-dimensional model of the dentition where the tooth to be restored is located.

According to the present invention, there is provided a dental preparation system, further comprising:

and the guide plate generating unit is used for generating a guide plate based on the outline surface of the dentition in the three-dimensional model of the dentition, and the guide plate is fixedly connected with the dentition visual mark to form the visual mark guide plate.

According to the dental preparation system provided by the invention, the visual mark guide plate is attached and fixed on the tooth row in a bone supporting manner.

According to the dental preparation system provided by the embodiment of the invention, the dentition visual mark and the instrument visual mark are arranged to realize real-time tracking and positioning of the dental preparation process, so that an operator can possibly determine the relation between an affected part and a surgical instrument in real time even in a narrow and non-direct-view environment in an oral cavity; on the basis, the dental robot is controlled to move by integrating visual calibration and hand-eye calibration, so that the tooth preparation precision is higher, and the operation efficiency and consistency are improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of one embodiment of a dental preparation system provided by the present invention;

FIG. 2 is a schematic representation of a three-dimensional model provided by the present invention;

FIG. 3 is a second schematic structural view of a dental preparation system according to the present invention;

reference numerals:

10-a visual marking guide; 11-dentition visual indicia; 20-a dental robot;

21-a mechanical positioning arm; 22-a surgical instrument; 23-instrument visual markers;

24-a force sensor; 30-a visual navigator; 40-preparing the control device;

50-probe tool.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Fig. 1 is a schematic structural diagram of a dental preparation system provided by the present invention, and as shown in fig. 1, the system includes a visual marking guide 10, a dental robot 20, a visual navigator 30, and a preparation control device 40;

wherein, the visual mark guide plate 10 is arranged on the dentition where the tooth to be restored is positioned, and the dentition visual mark 11 is arranged on the visual mark guide plate 10; the dental robot 20 comprises a mechanical positioning arm 21 and a surgical instrument 22 arranged at the tail end of the mechanical positioning arm 21, wherein an instrument visual mark 23 is arranged on the surgical instrument 22; the visual navigator 30 is used for detecting the position and the posture of the dentition visual mark 11 and the instrument visual mark 23; the preparation control device 40 performs vision calibration based on the position posture of the dentition vision mark 11, performs hand-eye calibration based on the position posture of the instrument vision mark 23, and controls the mechanical positioning arm 21 to operate based on the vision calibration result and the hand-eye calibration result.

Specifically, the visual marker is a marker capable of capturing position information in real time by a device such as a visual navigator or a visual sensor, and the visual marker may be formed by a set of reflective balls/reflective sheets. The dentition visual mark 11 and the apparatus visual mark 23 both belong to the same type of visual marks, and the dentition visual mark 11 and the apparatus visual mark 23 are different in arrangement position, and the dentition visual mark 11 is arranged at a position close to a tooth to be restored of a patient, so that the visual navigator 30 can capture the position posture of the tooth to be restored in real time; the instrument visual markers 23 are disposed on the surgical instrument 22, such as may be disposed at the distal end of the surgical instrument 22, to facilitate the visual navigator 30 to capture the position pose of the surgical instrument in real time.

The visual mark guide plate 10 is arranged to facilitate the arrangement of the dentition visual marks 11 on the dentition where the teeth to be restored are located, the dentition of different patients is considered to be different, the guide plate in the visual mark guide plate 10 is customized for a single patient, the dentition visual marks 11 are fixedly arranged on the dentition where the teeth to be restored are located through the guide plate which is attached to the outer contour surface of the dentition of the patient, and therefore in the tooth body preparation process, the dentition visual marks 11 can be changed along with the movement of the head of the patient, and the affected part position can be tracked by the tooth body preparation system in real time.

In consideration of the common cutting and grinding work in the tooth preparation process and errors possibly caused by hand shaking, in the embodiment of the invention, the hand is not used for directly controlling the surgical instrument, but the dental robot 20 is used for controlling instead of the hand, so that the shaking problem in the hand control process is avoided.

The dental robot 20 includes a mechanical positioning arm 21 and a surgical instrument 22, where the mechanical positioning arm 21 may include several positioning arms connected in series by a rotary joint to facilitate flexible movement of the mechanical positioning arm 21. In order to make the mechanical positioning arm 21 more flexible when being dragged for use or avoiding obstacles, the number of the positioning arms connected in series can be flexibly adjusted, so that the mechanical positioning arm 21 has a redundant freedom structure. Preferably, the mechanical positioning arm 21 here has at least 6 degrees of freedom. The surgical instrument 22 may be disposed on the end flange of the mechanical positioning arm 21, and similarly, an instrument visual mark 23 may be added to the surgical instrument 22 to achieve real-time positioning of the surgical instrument 22.

The visual navigator 30 can detect the position and orientation of the dentition visual marks 11 and the instrument visual marks 23 in real time and transmit the detected information to the preparation control apparatus 40. The visual navigator 30 can be fixed in place so that various types of visual markers can be positioned within its field of view.

The preparation control device 40 is used for controlling the mechanical positioning arm 21 to move according to the position and the posture of the dentition visual mark 11 and the instrument visual mark 23 detected by the visual navigator 30, thereby realizing the tooth preparation operation. The control of the motion of the mechanical positioning arm 21 referred to herein may be directly controlling the mechanical positioning arm 21 to move according to a set path to drive the surgical instrument 22 at the end of the mechanical positioning arm 21 to fully automatically complete the tooth preparation operation, or may also be adjusting the torque of each rotation key in the mechanical positioning arm 21 according to the relative position between the surgical instrument 22 and the area to be cut during the process of manually dragging the mechanical positioning arm 21 or the surgical instrument 22 by an operator to perform the tooth preparation operation, so that the operator can drag the surgical instrument to the area to be cut more easily to perform the tooth preparation, which is not specifically limited in the embodiment of the present invention.

Before the preparation control device 40 performs the mechanical positioning arm action, visual calibration and hand-eye calibration are also required. The visual calibration is the calibration aiming at the transformation relation between the virtual coordinate system and the visual coordinate system, and the hand-eye calibration is the calibration aiming at the transformation relation between the robot coordinate system and the visual coordinate system. Here, the virtual coordinate system is a coordinate system in which a three-dimensional model related to a dental preparation is constructed in advance, and a path plan for the dental preparation is generally formed based on the virtual coordinate system. The visual coordinate system is a coordinate system in which the visual navigator 30 is located, and the position and posture of each visual marker acquired by the visual navigator 30 are usually in the visual coordinate system. The robot coordinate system, that is, the robot end tool coordinate system reflects a coordinate system based on the dental robot 20 itself as a reference. After the visual navigator 30 detects the position and posture of each visual mark, the position and posture can be converted into a virtual coordinate system through a visual calibration result so as to facilitate display updating of the three-dimensional model and path planning based on the position and posture, and the planned path or control information can be converted into the visual coordinate system through the visual calibration result and then converted into a robot coordinate system through a hand-eye calibration result so as to directly control the dental robot 20 to execute corresponding actions.

According to the system provided by the embodiment of the invention, the dentition visual mark and the instrument visual mark are arranged to realize real-time tracking and positioning of the tooth preparation process, so that an operator can possibly determine the relation between an affected part and a surgical instrument in real time even in a narrow and non-direct-view environment in an oral cavity; on the basis, the dental robot is controlled to move by integrating visual calibration and hand-eye calibration, so that the tooth preparation precision is higher, and the operation efficiency and consistency are improved.

Based on the above embodiment, the preliminary control means includes:

the visual calibration unit is used for performing visual calibration on the basis of the position postures of the dentition visual markers in the visual coordinate system and the virtual coordinate system;

the hand-eye calibration unit is used for performing hand-eye calibration based on the position postures of the instrument visual marker in the visual coordinate system and the robot coordinate system;

and the mechanical arm control unit is used for converting the virtual control information in the virtual coordinate system into the robot coordinate system based on the vision calibration result and the hand-eye calibration result to obtain machine control information so as to control the motion of the mechanical positioning arm.

Specifically, before the dental preparation operation, three-dimensional modeling is performed on the dentition where the tooth to be restored is located, and a coordinate system where the three-dimensional model obtained by the modeling is located is a virtual coordinate system. In order to realize precise robot-assisted surgery, a three-dimensional model in a virtual coordinate system needs to be matched with a corresponding actual position, namely, visual calibration is carried out. The visual calibration unit can convert the position posture of the dentition visual mark obtained by the detection of the visual navigator and the position of the corresponding point under the virtual coordinate system, so that a space conversion relation between the dentition visual mark and the dentition visual mark, namely a visual calibration result, is obtained.

In addition, the hand-eye calibration unit can detect the position and the posture of the obtained instrument visual mark through the visual navigator and convert the position and the posture of the instrument visual mark in the robot coordinate system, so that a spatial conversion relation between the two is obtained, namely a hand-eye calibration result. Alternatively, the position posture of the instrument visual marker in the robot coordinate system can be calculated by the angle of the rotary joint between each of the mechanical positioning arms.

The mechanical arm control unit is used for controlling the motion of the mechanical positioning arm, and considering that the common control information is generated based on a virtual coordinate system, and the virtual control information cannot be directly applied to the motion control of the mechanical positioning arm, the control information in the virtual coordinate system needs to be converted into the control information in the robot coordinate system by combining the vision calibration and the hand-eye calibration, so that the machine control information is obtained to control the motion of the mechanical positioning arm.

Based on any of the above embodiments, the visual calibration unit is configured to:

acquiring the relative position and posture between the probe tool and the dentition visual mark when the probe tool touches a plurality of mark points on the dentition, wherein the tail end of the probe tool is provided with the visual mark;

and determining a vision calibration result based on the relative position and posture of each mark point and the position and posture of each mark point in the three-dimensional model of the dentition under the virtual coordinate system.

Specifically, a group of light reflecting balls/light reflecting pieces are fixed at the tail end of the probe tool and used as visual marks, and the visual marks are calibrated when leaving a factory, so that the probe tip can be in contact with a point to be measured to obtain the spatial position of the point to be measured in a visual coordinate system.

The position posture of the dentition visual mark on the dentition of the patient under the visual coordinate system can be represented by a homogeneous matrix T_MAnd (4) showing. In the visual calibration process, an operator can hold the probe tool to sequentially touch a plurality of mark points on the dentition of a patient, such as the points with obvious characteristics, such as the tooth cusp end points, so as to acquire the coordinates of each mark point in a visual coordinate system. Considering that the head position of the patient may change during the vision calibration process, in order to obtain a fixed relative position relationship, the coordinates of each landmark point in the visual coordinate system may be converted into the coordinate system of the dentition visual mark, so as to obtain the relative position, denoted as P, between each landmark point and the dentition visual mark_M1、P_M2、…P_MnAnd n is the number of the mark points. Where the relative positions of the various landmark points and the dentition visual indicia are fixed and invariant.

Assuming that the position of each mark point in the three-dimensional model of dentition is P under the virtual coordinate system_s1、P_s2、…P_snThe optimal transformation can be calculated for the two sets of point sets in one-to-one correspondence, so that a spatial transformation relationship between the two point sets is obtained, and the two corresponding point sets can be matched together through rotation and translation. The obtained vision calibration result can be obtained at the position T of the dentition vision mark acquired by the vision navigator in real time_MAnd then, indirectly calculating the position posture of the three-dimensional model in the visual coordinate system.

Based on any embodiment above, the robot arm control unit is further configured to:

and planning a restoration path based on the three-dimensional model of the dentition and the restoration model to obtain a cutting path as virtual control information, wherein the restoration model is constructed based on the three-dimensional model.

Specifically, fig. 2 is a schematic diagram of a three-dimensional model provided by the present invention, the left side of an arrow in fig. 2 is a schematic diagram of a three-dimensional model of dentition, the right side of the arrow is a schematic diagram of a repair model constructed based on the three-dimensional model, a region filled with oblique lines in the three-dimensional model is a region to be cut, and the repair model is the three-dimensional model with the region to be cut removed. After obtaining the three-dimensional model and the restoration model of the dentition, the mechanical arm control unit can determine the region to be cut based on the three-dimensional model and the restoration model, plan the cutting path required by the dental restoration based on the region to be cut, and use the cutting path obtained from the planning as virtual control information for reference during dental preparation.

Further, the generation of the cutting path can be realized by using numerical control machining.

According to any of the above embodiments, the dental robot further comprises a force sensor disposed at an end of the mechanical positioning arm;

the robot arm control unit is further configured to:

and determining virtual control information based on the moment information fed back by the force sensor and the relative position information of the area to be cut in the dentition and the surgical instrument in the three-dimensional model.

In particular, a force sensor can be arranged on a flange at the tail end of the mechanical positioning arm, and a surgical instrument is arranged at one end of the force sensor, so that the applied torque when an operator holds the surgical instrument to perform resection in a dragging mode can be acquired through the force sensor. Preferably, the force sensor here may be a six-dimensional force sensor.

Correspondingly, the mechanical arm control unit can sense the operation intention of an operator through torque information fed back by the force sensor, and the flexible dragging of the mechanical positioning arm is realized through methods such as impedance and admittance control. In the passive cutting implementation process, the visual navigator can monitor the position of the surgical instrument at the tail end of the robot relative to an ideal repair model in real time, relative position information of a to-be-cut area and the surgical instrument in the three-dimensional model is obtained through conversion of a visual calibration result of the mechanical arm control unit, the relative position information reflects whether the surgical instrument is in the to-be-cut area, if the fact that the tip of the surgical instrument enters the ideal repair area, namely the non-cutting area is detected, the mechanical positioning arm is controlled to stop moving, the mechanical positioning arm can move again after returning to the to-be-cut area, and therefore the situation that the surgical instrument mistakenly cuts the ideal repair area is avoided.

Based on any one of the above embodiments, the mechanical positioning arm comprises a plurality of positioning arms connected in series through rotary joints, and the rotary joints are provided with servo torque motors; the machine control information is used to control each servo torque motor.

Specifically, when the tail end of the surgical instrument is positioned in a region to be cut, the gravity moment of each rotary joint can be calculated according to the robot dynamic model, and the gravity moment is offset through the torque provided by the servo torque motor, so that the serial positioning arm is more flexible and convenient to drag. In addition, the contact rigidity of the mechanical positioning arm can be adjusted according to the distance between the tail end of the surgical instrument and the ideal restoration area, and the contact rigidity is increased along with the reduction of the distance close to the ideal restoration area, so that the mechanical positioning arm can be dragged by applying certain force.

When the tail end of the surgical instrument is positioned in an ideal prosthesis area, the output torque of the servo torque motor at each rotary joint in the serial positioning arm can be adjusted according to the mechanism control information, so that an operator can obtain feedback on force sense when dragging the mechanical positioning arm, the surgical precision and the operation safety are improved, and healthy tissues are prevented from being injured. Furthermore, the output torque of the servo torque motors is adjusted, and the torque which should be output by each servo torque motor during dragging can be calculated according to the preset parameters such as contact rigidity and damping, so that the mechanical positioning arm dynamically changes the sensitivity and gives different force feedback to operators.

Based on any of the above embodiments, the system further comprises:

and the display equipment is used for converting the position postures of the dentition visual mark and the instrument visual mark in the visual coordinate system into the virtual coordinate system based on the visual calibration result, and updating and displaying the position postures of the dentition and the three-dimensional model of the surgical instrument.

In the system provided by the embodiment of the invention, the application of the display equipment enables the tooth preparation operation in the non-direct-view environment to be visual and visible, can more intelligently assist the operator in tooth preparation, and improves the reliability of tooth preparation.

Based on any of the above embodiments, the system further comprises:

and the intraoral scanning equipment is used for intraoral scanning of the patient to obtain a three-dimensional model of the dentition where the tooth to be restored is located.

The three-dimensional model obtained here is specifically a three-dimensional curved surface model, and the dentition where the tooth to be restored is located may be an upper dentition or a lower dentition, which is specifically determined according to the location where the tooth to be restored is located, and the embodiment of the present invention is not limited.

Based on any of the above embodiments, the system further comprises:

the guide plate generating unit is used for generating a guide plate based on the outline surface of the dentition in the three-dimensional model of the dentition, and the guide plate is fixedly connected with the dentition visual mark to form a visual mark guide plate;

the visual mark guide plate is attached and fixed on the tooth row in a bone supporting mode.

Specifically, a guide plate can be designed for a patient according to a three-dimensional model of the dentition obtained by oral scanning, the inner shape of the guide plate is determined by the outer contour surface of the dentition, and the guide plate is closely and closely fixed on the dentition of the patient in a bone-supporting mode. The guide plate can be rapidly processed and manufactured in a 3D printing mode.

Based on the above embodiment, fig. 3 is a second schematic structural diagram of the dental preparation system provided by the present invention, and as shown in fig. 3, the dental preparation method based on the dental preparation system includes the following steps:

firstly, intraoral scanning is carried out on a patient by using intraoral scanning equipment to obtain a three-dimensional model of the dentition where the tooth to be restored is located.

Secondly, three-dimensional design software is applied to design an ideal restoration model according to the three-dimensional model of the dentition where the tooth to be restored is located.

Then, a guide plate is designed for the patient according to the three-dimensional model of the tooth row obtained by the oral scan, the inner shape of the guide plate is determined by the outer contour surface of the tooth row, and the guide plate is closely attached and fixed on the tooth row of the patient in a bone supporting mode. Further, a visual marker guide 10 is formed by attaching visual dentition markers 11 to the guide. Here, the dentition visual markers 11 and the guide plate may be fixed together by means of a plug-in connection or other mechanical connection, and the dentition visual markers 11 may include at least 3 reflective balls/sheets.

Then, the probe tool 50 is applied for visual calibration. Here, the visual mark is fixed at the end of the probe tool 50 in advance, so that an operator can hold the probe tool 50 and sequentially touch a plurality of mark points on the dentition of the patient, and simultaneously, the visual navigator 30 records the positions of the visual mark on the probe tool 50 and the dentition visual mark 11 under the visual coordinate system at the corresponding moment, thereby obtaining the relative positions between each mark point and the dentition visual mark. On the basis, the vision calibration result can be obtained based on the relative position and posture of each mark point and the position and posture of each mark point in the dentition three-dimensional model under the virtual coordinate system.

In addition, the position and the posture of the instrument visual mark 23 detected by the visual navigator 30 and the position and the posture of the instrument visual mark 23 in the robot coordinate system can be transformed, so as to obtain the spatial transformation relationship between the two, i.e. the hand-eye calibration result.

On the basis of the existing three-dimensional model and restoration model of dentition, a restoration path can be planned in a to-be-cut area on the three-dimensional model in a data processing mode, so that a cutting path is obtained, the path is converted into a visual coordinate system based on a visual calibration result, and then is converted into a robot coordinate system through a hand-eye calibration result, so that the tip of a surgical instrument 22 at the tail end of a dental robot 20 is directly controlled to move along a cutter path, the to-be-cut area is removed, and the tooth preparation is actively completed.

Alternatively, the resection may be performed by the operator holding the surgical instrument 22 in a tug. Because the tail end of the mechanical positioning arm 21 is provided with the force sensor 24, the force and the moment in multiple directions can be measured, the operation intention of a doctor is sensed, and based on the feedback information of the force sensor 24, the flexible dragging of the mechanical positioning arm 21 can be realized through methods such as impedance and admittance control. During the passive cutting process, the visual navigator 30 can monitor the position of the surgical instrument 22 relative to the ideal repair model in real time, and if the tip of the surgical instrument 22 is detected to enter the ideal repair area, the mechanical positioning arm 21 is controlled to stop moving and move again after returning to the area to be cut, so that the surgical instrument is prevented from cutting the ideal repair area by mistake.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.