阅读说明：本技术 一种光学导航的牙种植机器人系统及其标定方法 (Optical navigation dental implantation robot system and calibration method thereof ) 是由 杨荣骞 晏猋 梁可思 张文龙 于 2021-07-30 设计创作，主要内容包括：本发明公开了一种光学导航的牙种植机器人系统及其标定方法,包括光学位置示踪器、六自由度机械臂、机械臂法兰盘末端夹持定位工具、牙种植手机、叉形工具、近红外光学定位系统和手术导航控制系统；光学位置示踪器由牙槽骨固定槽、第一连接杆、五点标记球固定板和光学标记球组成,六自由度机械臂末端安装有机械臂法兰盘末端夹持定位工具,由法兰连接片、第二连接杆、四点标记球固定板、光学标记球和牙种植手机夹持工具组成,夹持有牙种植手机,叉形工具提供车针的精确位置,近红外光学定位系统获取各光学标记球位置信息,手术导航控制系统用以信息数据处理。本发明通过设计光学位置示踪器等结构,提出标定方法,提高了精度和系统稳定性。(The invention discloses an optical navigation dental implantation robot system and a calibration method thereof, wherein the optical navigation dental implantation robot system comprises an optical position tracer, a six-degree-of-freedom mechanical arm, a clamping and positioning tool for the tail end of a flange plate of the mechanical arm, a dental implantation mobile phone, a forked tool, a near-infrared optical positioning system and an operation navigation control system; the optical position tracer comprises an alveolar bone fixing groove, a first connecting rod, a five-point marker ball fixing plate and an optical marker ball, a clamping and positioning tool for the tail end of a mechanical arm flange plate is mounted at the tail end of a six-degree-of-freedom mechanical arm, and the clamping and positioning tool comprises a flange connecting piece, a second connecting rod, a four-point marker ball fixing plate, an optical marker ball and a dental implant mobile phone clamping tool, the dental implant mobile phone is clamped, a fork-shaped tool provides the accurate position of a car needle, a near-infrared optical positioning system acquires the position information of each optical marker ball, and an operation navigation control system is used for processing information data. The invention provides a calibration method by designing structures such as an optical position tracer and the like, and improves the precision and the system stability.)

1. An optical navigation dental implantation robot system is characterized in that: the device comprises an optical position tracer, a six-degree-of-freedom mechanical arm, a clamping and positioning tool for the tail end of a flange plate of the mechanical arm, a dental implant mobile phone, a forked tool, a near-infrared optical positioning system and an operation navigation control system; the optical position tracer comprises an alveolar bone fixing groove, a first connecting rod, a five-point marker ball fixing plate and optical marker balls, wherein one end of the first connecting rod is connected with the alveolar bone fixing groove, the other end of the first connecting rod is connected with the center of the five-point marker ball fixing plate, the five-point marker ball fixing plate is provided with five cantilevers extending from the centers of the five cantilevers along five different directions, the tail end of each cantilever is provided with one optical marker ball, the distance between every two adjacent optical marker balls is larger than a preset value, and the optical position tracer is used for establishing the registration relation between the CT image space of a patient and the actual operation space; the tail end of the six-degree-of-freedom mechanical arm clamps the dental implant mobile phone through a clamping and positioning tool at the tail end of the mechanical arm flange plate, and the dental implant mobile phone is driven through the six-degree-of-freedom mechanical arm; the clamping and positioning tool for the tail end of the flange plate of the mechanical arm consists of a flange connecting plate, a second connecting rod, a four-point marking ball fixing plate, an optical marking ball and a dental implant mobile phone clamping tool, wherein the flange connecting plate is fixed on the flange plate at the tail end of the mechanical arm with six degrees of freedom through screws and is connected with one end of the second connecting rod, the other end of the second connecting rod is connected with the dental implant mobile phone clamping tool, the four-point marking ball fixing plate is arranged in the middle of the second connecting rod and is provided with four cantilevers, the tail end of each cantilever is provided with the optical marking ball, and the distance between every two adjacent optical marking balls is larger than a preset value; the dental implant mobile phone is used for performing cavity preparation and is clamped by a dental implant mobile phone clamping tool; the fork-shaped tool is provided with four cantilevers extending from the center of the fork-shaped tool along four different directions, the tail end of each cantilever is provided with one optical marking ball, and the distance between every two adjacent optical marking balls is larger than a preset value; the near-infrared optical positioning system is used for acquiring the position information of each optical marker ball in real time and determining the positions of the oral cavity of a patient, the tail end of the six-degree-of-freedom mechanical arm and the needle point of the car needle of the dental implant mobile phone; the operation navigation control system is used for receiving the position information sent by the near-infrared optical positioning system in real time, carrying out oral cavity image segmentation and three-dimensional reconstruction and visualized path planning and motion control, and realizing operation navigation in an operation.

2. An optically navigated dental implant robot system according to claim 1, wherein: the alveolar bone fixing groove is embedded on the alveolar bone of the patient through a fixing screw between the alveolar bone fixing groove and the first connecting rod, and the shape of the alveolar bone fixing groove is matched and customized according to the size of the oral cavity of the patient.

3. An optically navigated dental implant robot system according to claim 1, wherein: the clamping and positioning tool at the tail end of the flange plate of the mechanical arm is used for clamping a dental implant mobile phone and representing the position information of the tool at the tail end of the six-degree-of-freedom mechanical arm.

4. An optically navigated dental implant robot system according to claim 1, wherein: the center of the fork-shaped tool is vertically propped against a turning needle of the dental implant handpiece before operation and is used for providing the accurate position of the turning needle.

5. The method for calibrating an optically navigated dental implant robot system of any of claims 1 to 4, comprising the steps of:

s1, obtaining the conversion relation between the coordinate system of the robot base and the coordinate system of the tail end of the six-degree-of-freedom mechanical arm according to the internal parameters of the robot; calculating unit vectors from an initial pose to an offset pose of the six-degree-of-freedom mechanical arm to obtain conversion relations between a robot base coordinate system and a near-infrared optical positioning system coordinate system, between a six-degree-of-freedom mechanical arm tail end coordinate system and a near-infrared optical positioning system coordinate system, and between a dental implant mobile phone coordinate system and a near-infrared optical positioning system coordinate system;

s2, solving the conversion relation between the dental implant mobile phone coordinate system and the dental implant mobile phone needle tail end coordinate system by using singular value decomposition based on the conversion relation between the dental implant mobile phone coordinate system and the near infrared optical positioning system coordinate system;

s3, calculating a conversion relation between the tooth implantation mobile phone car needle tail end coordinate system and the near infrared optical positioning system coordinate system based on the conversion relation between the tooth implantation mobile phone coordinate system and the near infrared optical positioning system coordinate system and the conversion relation between the tooth implantation mobile phone coordinate system and the tooth implantation mobile phone car needle tail end coordinate system;

s4, based on the conversion relation between a robot base coordinate system and a six-degree-of-freedom mechanical arm tail end coordinate system, between the six-degree-of-freedom mechanical arm tail end coordinate system and a tooth implantation mobile phone coordinate system, and between the tooth implantation mobile phone coordinate system and a tooth implantation mobile phone car needle tail end coordinate system, the near-infrared optical positioning system captures the positions of any three optical mark points on the clamping and positioning tool at the tail end of the flange of the mechanical arm in real time, the conversion relation between the tooth implantation mobile phone coordinate system and the near-infrared optical positioning system coordinate system is solved in real time by utilizing singular value decomposition, and the conversion relation between all coordinate systems in a closed loop is updated.

6. The method for calibrating an optically navigated dental implantation robot system according to claim 5, wherein said S1 comprises the steps of:

s101, controlling the tail end of a six-degree-of-freedom mechanical arm to respectively perform unit forward motion along three coordinate axes of a robot base coordinate system by taking any one optical mark point on a clamping and positioning tool at the tail end of a mechanical arm flange plate as a reference; capturing the positions of the optical mark points before and after movement by the near-infrared optical positioning system, and calculating a unit vector of the tail end of the six-degree-of-freedom mechanical arm from an initial pose to an offset pose under a near-infrared optical positioning system coordinate system to obtain a conversion relation between a robot base coordinate system and a near-infrared optical positioning system coordinate system;

s102, controlling the tail end of the six-degree-of-freedom mechanical arm to respectively make unit forward motion along three coordinate axes of a coordinate system at the tail end of the six-degree-of-freedom mechanical arm by taking any one optical mark point on the clamping and positioning tool at the tail end of the flange plate of the mechanical arm as a reference; capturing the positions of the optical mark points before and after movement by the near-infrared optical positioning system, and calculating a unit vector of the tail end of the six-degree-of-freedom mechanical arm from an initial pose to an offset pose under a coordinate system of the near-infrared optical positioning system to obtain a rotation matrix of the coordinate system of the tail end of the six-degree-of-freedom mechanical arm and the coordinate system of the near-infrared optical positioning system;

s103, clamping any three optical mark points on the positioning tool by using the tail end of the flange plate of the mechanical arm to establish a coordinate system of the dental implant mobile phone; the near-infrared optical positioning system captures the position information of the three optical mark points when the six-degree-of-freedom mechanical arm reaches the initial pose, and the conversion relation between the coordinate system of the teething implanting mobile phone and the coordinate system of the near-infrared optical positioning system is calculated.

7. The method for calibrating an optically navigated dental implantation robot system according to claim 5, wherein said S2 comprises the steps of:

s201, placing a fork-shaped tool at the needle point of a machine needle of a dental implant mobile phone, and capturing the positions of four optical mark points on the fork-shaped tool by a near-infrared optical positioning system;

s202, based on the conversion relation between the dental implant mobile phone coordinate system and the near-infrared optical positioning system coordinate system, converting the position information of the four optical mark points in the near-infrared optical positioning system coordinate system into the position information in the dental implant mobile phone coordinate system;

s203, establishing a dental implant mobile phone car needle terminal coordinate system by using any three optical marking points on the fork-shaped tool, and solving a conversion relation between the dental implant mobile phone coordinate system and the dental implant mobile phone car needle terminal coordinate system by using a singular value decomposition method based on the position information of the four optical marking points in the dental implant mobile phone coordinate system.

8. The method for calibrating an optically navigated dental implantation robot system according to claim 5, wherein said S3 comprises the steps of:

s301, establishing a conversion relation between any point in an operation space and position information under a near-infrared optical positioning system coordinate system under a dental implant mobile phone car needle tail end coordinate system:

wherein, P_oAnd P_pRespectively represents the position information of the point under the coordinate system of the tail end of the dental implant mobile phone needle and the coordinate system of the near infrared optical positioning system, R_poAnd T_poRespectively representing a rotation matrix and a translation matrix R between a dental implant mobile phone car needle tail end coordinate system and a near infrared optical positioning system coordinate system_toAnd T_toRespectively representing a rotation matrix and a translation matrix R between a dental implant mobile phone coordinate system and a near-infrared optical positioning system coordinate system_ptAnd T_ptRespectively representing a rotation matrix and a translation matrix of a dental implant mobile phone needle tail end coordinate system and a dental implant mobile phone coordinate system;

and S302, calculating a conversion relation between the coordinate system of the tail end of the dental implant mobile phone needle and the coordinate system of the near-infrared optical positioning system by using the conversion relation established in the S301.

9. The method for calibrating an optically-navigated dental implantation robot system according to claim 5, wherein the calibration is performed preoperatively using steps S1-S3, and when the relative position of the surgical robot and the near-infrared optical positioning system changes, the closed-loop switching relationship is updated using step S4 to complete a new calibration cycle.

Technical Field

The invention relates to the technical field of dental implantation, in particular to an optical navigation dental implantation robot system and a calibration method thereof.

Background

Dental implant surgery is one of the common dental restoration methods, and success or failure is determined by the precision of cavity preparation on alveolar bones. If the deviation of the actual implantation position of the implant from the preoperative plan is large, the implant may be loosened or mechanically broken, thereby causing a series of complications; for patients with thinner jaw areas, if the cavity preparation is severely inaccurate, the procedure will not only fail, but also cause irreversible adjacent root and mandibular nerve canal damage, increasing the risk of the procedure.

Current dental implant procedures are highly dependent on the clinical experience of the physician. On the one hand, the period for cultivating a qualified dentist is long and the cost is high; on the other hand, long-time surgical operations can cause fatigue in the wrists of the surgeon, thereby causing human error. Therefore, there is a need for a dental implant surgical robotic system that makes the surgery more intelligent and automated.

At present, the main problem that tooth implantation robot faces lies in lacking accurate positioning technique, leads to tooth implantation surgical robot can't be applicable to narrow and small, complicated oral cavity internal environment. On one hand, the lack of accurate positioning tools and clamping tools does not provide accurate spatial location information for the system; on the other hand, a mobile hand-eye calibration algorithm with high robustness is lacked, and once the relative spatial positions of the robot and the navigation system are changed, the accurate conversion of coordinates between the robot and the navigation system cannot be realized.

Disclosure of Invention

The invention aims to overcome the defects and shortcomings of the prior art, provides an optical navigation dental implantation robot system and a calibration method thereof for dental implantation surgery, is an automatic and high-precision robot-assisted surgery implementation scheme, designs an optical position tracer, realizes accurate registration of an image space and an operation space, and improves the precision of operation registration and the precision of a navigation system; the calibration method can ensure the stability and robustness of the cooperation between the mechanical arm and the navigation system, and can still accurately register when the relative positions of the mechanical arm and the navigation system are changed.

In order to achieve the purpose, the technical scheme provided by the invention is as follows: an optical navigation dental implantation robot system comprises an optical position tracer, a six-degree-of-freedom mechanical arm, a clamping and positioning tool at the tail end of a flange plate of the mechanical arm, a dental implantation mobile phone, a forked tool, a near-infrared optical positioning system and an operation navigation control system; the optical position tracer comprises an alveolar bone fixing groove, a first connecting rod, a five-point marker ball fixing plate and optical marker balls, wherein one end of the first connecting rod is connected with the alveolar bone fixing groove, the other end of the first connecting rod is connected with the center of the five-point marker ball fixing plate, the five-point marker ball fixing plate is provided with five cantilevers extending from the centers of the five cantilevers along five different directions, the tail end of each cantilever is provided with one optical marker ball, the distance between every two adjacent optical marker balls is larger than a preset value, and the optical position tracer is used for establishing the registration relation between the CT image space of a patient and the actual operation space; the tail end of the six-degree-of-freedom mechanical arm clamps the dental implant mobile phone through a clamping and positioning tool at the tail end of the mechanical arm flange plate, and the dental implant mobile phone is driven through the six-degree-of-freedom mechanical arm; the clamping and positioning tool for the tail end of the flange plate of the mechanical arm consists of a flange connecting plate, a second connecting rod, a four-point marking ball fixing plate, optical marking balls and a dental implant mobile phone clamping tool, wherein the flange connecting plate is fixed on the flange plate at the tail end of the mechanical arm with six degrees of freedom through screws and is connected with one end of the second connecting rod, the other end of the second connecting rod is connected with the dental implant mobile phone clamping tool, the four-point marking ball fixing plate is arranged in the middle of the second connecting rod and is provided with four cantilevers, one optical marking ball is arranged at the tail end of each cantilever, and the distance between every two adjacent optical marking balls is larger than a preset value; the dental implant mobile phone is used for performing cavity preparation and is clamped by a dental implant mobile phone clamping tool; the fork-shaped tool is provided with four cantilevers extending from the center of the fork-shaped tool along four different directions, the tail end of each cantilever is provided with an optical marking ball, and the distance between every two adjacent optical marking balls is larger than a preset value; the near-infrared optical positioning system is used for acquiring the position information of each optical marker ball in real time and determining the positions of the oral cavity of a patient, the tail end of the six-degree-of-freedom mechanical arm and the needle point of the car needle of the dental implant mobile phone; the operation navigation control system is used for receiving the position information sent by the near-infrared optical positioning system in real time, carrying out oral cavity image segmentation and three-dimensional reconstruction and visualized path planning and motion control, and realizing operation navigation in an operation.

Further, the alveolar bone fixing groove is embedded on the alveolar bone of the patient through a fixing screw between the alveolar bone fixing groove and the first connecting rod, and the shape of the alveolar bone fixing groove is matched and customized according to the size of the oral cavity of the patient.

Further, the clamping and positioning tool at the tail end of the flange plate of the mechanical arm is used for clamping the dental implant mobile phone and representing the position information of the tool at the tail end of the six-degree-of-freedom mechanical arm.

Further, the center of the fork-shaped tool is vertically pressed against the turning needle of the dental implant handpiece before operation, so as to provide the accurate position of the turning needle.

The invention also provides a calibration method of the dental implantation robot system with the optical navigation, which comprises the following steps:

s1, obtaining the conversion relation between the coordinate system of the robot base and the coordinate system of the tail end of the six-degree-of-freedom mechanical arm according to the internal parameters of the robot; calculating unit vectors from an initial pose to an offset pose of the six-degree-of-freedom mechanical arm to obtain conversion relations between a robot base coordinate system and a near-infrared optical positioning system coordinate system, between a six-degree-of-freedom mechanical arm tail end coordinate system and a near-infrared optical positioning system coordinate system, and between a dental implant mobile phone coordinate system and a near-infrared optical positioning system coordinate system;

s2, solving the conversion relation between the dental implant mobile phone coordinate system and the dental implant mobile phone needle tail end coordinate system by using singular value decomposition based on the conversion relation between the dental implant mobile phone coordinate system and the near infrared optical positioning system coordinate system;

s3, calculating a conversion relation between the dental implant mobile phone needle tail end coordinate system and the near infrared optical positioning system coordinate system based on the conversion relation between the dental implant mobile phone coordinate system and the near infrared optical positioning system coordinate system and between the dental implant mobile phone coordinate system and the dental implant mobile phone needle tail end coordinate system;

s4, based on the conversion relation between a robot base coordinate system and a six-degree-of-freedom mechanical arm tail end coordinate system, between the six-degree-of-freedom mechanical arm tail end coordinate system and a tooth implantation mobile phone coordinate system, and between the tooth implantation mobile phone coordinate system and a tooth implantation mobile phone car needle tail end coordinate system, the near-infrared optical positioning system captures the positions of any three optical mark points on the clamping and positioning tool at the tail end of the flange of the mechanical arm in real time, the conversion relation between the tooth implantation mobile phone coordinate system and the near-infrared optical positioning system coordinate system is solved in real time by utilizing singular value decomposition, and the conversion relation between all coordinate systems in a closed loop is updated.

Further, the S1 includes the following steps:

s101, controlling the tail end of a six-degree-of-freedom mechanical arm to respectively move forwards in unit along three coordinate axes of a robot base coordinate system by taking any one optical mark point on a clamping and positioning tool at the tail end of a mechanical arm flange plate as a reference; capturing the positions of the optical mark points before and after movement by the near-infrared optical positioning system, and calculating a unit vector of the tail end of the six-degree-of-freedom mechanical arm from an initial pose to an offset pose under a near-infrared optical positioning system coordinate system to obtain a conversion relation between a robot base coordinate system and a near-infrared optical positioning system coordinate system;

s102, controlling the tail end of the six-degree-of-freedom mechanical arm to respectively perform single-position forward motion along three coordinate axes of a coordinate system at the tail end of the six-degree-of-freedom mechanical arm by taking any one optical mark point on the clamping and positioning tool at the tail end of the flange plate of the mechanical arm as a reference; capturing the positions of the optical mark points before and after movement by the near-infrared optical positioning system, and calculating a unit vector of the tail end of the six-degree-of-freedom mechanical arm from an initial pose to an offset pose under a coordinate system of the near-infrared optical positioning system to obtain a rotation matrix of the coordinate system of the tail end of the six-degree-of-freedom mechanical arm and the coordinate system of the near-infrared optical positioning system;

s103, clamping any three optical mark points on the positioning tool by using the tail end of the flange plate of the mechanical arm to establish a coordinate system of the dental implant mobile phone; the near-infrared optical positioning system captures the position information of the three optical mark points when the six-degree-of-freedom mechanical arm reaches the initial pose, and the conversion relation between the coordinate system of the teething implanting mobile phone and the coordinate system of the near-infrared optical positioning system is calculated.

Further, the S2 includes the following steps:

s201, placing a fork-shaped tool at the needle point of a machine needle of a dental implant mobile phone, and capturing the positions of four optical mark points on the fork-shaped tool by a near-infrared optical positioning system;

s202, based on a conversion relation between a dental implant mobile phone coordinate system and a near-infrared optical positioning system coordinate system, converting position information of the four optical mark points in the near-infrared optical positioning system coordinate system into position information in the dental implant mobile phone coordinate system;

s203, establishing a dental implant handpiece needle end coordinate system by using any three optical marking points on the forked tool, and solving a conversion relation between the dental implant handpiece coordinate system and the dental implant handpiece needle end coordinate system by using a singular value decomposition method based on the position information of the four optical marking points in the dental implant handpiece coordinate system.

Further, the S3 includes the following steps:

s301, establishing a conversion relation between any point in the operation space and position information under a coordinate system of a near infrared optical positioning system under a dental implant mobile phone car needle tail end coordinate system:

wherein, P_oAnd P_pRespectively represents the position information of the point under the coordinate system of the dental implant mobile phone needle end and the coordinate system of the near infrared optical positioning system, R_poAnd T_poRespectively representing a rotation matrix and a translation matrix R between a dental implant mobile phone car needle tail end coordinate system and a near infrared optical positioning system coordinate system_toAnd T_toRespectively representing a rotation matrix and a translation matrix R between a dental implant mobile phone coordinate system and a near-infrared optical positioning system coordinate system_ptAnd T_ptRespectively represent the coordinate system of the tail end of the hand-held machine needle of the dental implant anda rotation matrix and a translation matrix of a dental implant mobile phone coordinate system;

and S302, calculating a conversion relation between the coordinate system of the tail end of the dental implant mobile phone needle and the coordinate system of the near-infrared optical positioning system by using the conversion relation established in the S301.

Further, before the operation, the calibration is performed by using the steps S1-S3, and when the relative position between the surgical robot and the near-infrared optical positioning system is changed, the conversion relation of the closed loop is updated by using the step S4, so that a new calibration is completed.

Compared with the prior art, the invention has the following advantages and beneficial effects:

1. the optical position tracer designed by the invention has an exquisite structure and can realize customization; and 3D printing is adopted for manufacturing, so that the price is low. Different from other optical position tracers adopting two-dimensional checkerboards, the optical marker ball adopted by the invention has higher optical positioning precision which can reach 0.12 mm.

2. The clamping and positioning tool for the tail end of the flange plate of the mechanical arm, which is designed by the invention, has a simple and reliable structure and is convenient to process and manufacture; the real-time positioning and tracking of the surgical tool can be realized; the installation is convenient, and the flange plate at the tail end of the six-freedom-degree mechanical arm is fixed through screws.

3. The forked tool designed by the invention is convenient to use, can be used only by being placed at the needle point of the dental implant mobile phone lathe needle, and has the advantages of simple and exquisite structure, higher reliability and high matching precision.

4. The calibration method designed by the invention has high precision and wide use scene, and is suitable for various complex operation scenes; the rapid calibration of the robot and the navigation system can be realized by less input data; the navigation system and the surgical robot system can keep relative independence of position relation and can work in a mutual cooperation mode, and the robustness is high.

Drawings

Fig. 1 is an overall schematic diagram of an optical navigation dental implant robot system.

Fig. 2 is a schematic diagram of an optical position tracer.

Fig. 3 is a schematic structural diagram of the clamping and positioning tool at the end of the flange of the mechanical arm.

Fig. 4 is a schematic view of a fork tool.

Detailed Description

The present invention will be further described with reference to specific examples, but the embodiments of the present invention are not limited thereto.

Referring to fig. 1 to 4, the embodiment discloses an optical navigation dental implantation robot system, which includes an optical position tracer 1, a six-degree-of-freedom mechanical arm 2, a mechanical arm flange end clamping and positioning tool 3, a dental implantation mobile phone 4, a fork-shaped tool 5, a near-infrared optical positioning system 6 and an operation navigation control system 7; the optical position tracer 1 comprises an alveolar bone fixing groove 101, a first connecting rod 102, a five-point marker ball fixing plate 103 and optical marker balls 104, wherein the alveolar bone fixing groove 101 is embedded in an alveolar bone of a patient through a fixing screw between the alveolar bone fixing groove 101 and the first connecting rod 102, the shape of the alveolar bone fixing groove is matched and customized according to the size of the oral cavity of the patient, one end of the first connecting rod 102 is connected with the alveolar bone fixing groove 101, the other end of the first connecting rod 102 is connected with the center of the five-point marker ball fixing plate 103, five cantilevers extend from the centers of the five-point marker ball fixing plate 103 along five different directions, the tail end of each cantilever is provided with one optical marker ball 104, the distance between every two adjacent optical marker balls 104 is larger than 4cm, and the optical marker balls are used for establishing the registration relation between a CT image space of the patient and an actual operation space; the tail end of the six-degree-of-freedom mechanical arm 2 clamps the dental implant mobile phone 4 through the mechanical arm flange plate tail end clamping and positioning tool 3, and the dental implant mobile phone 4 is driven through the six-degree-of-freedom mechanical arm 2; the clamping and positioning tool 3 for the tail end of the flange plate of the mechanical arm consists of a flange connecting plate 301, a second connecting rod 302, a four-point marking ball fixing plate 303, an optical marking ball 304 and a dental implant mobile phone clamping tool 305 and is used for representing the position information of the tool at the tail end of the six-degree-of-freedom mechanical arm, the flange connecting plate 301 is fixed on the flange plate 201 at the tail end of the six-degree-of-freedom mechanical arm 2 through a screw 306 and is connected with one end of the second connecting rod 302, the other end of the second connecting rod 302 is connected with the dental implant mobile phone clamping tool 305, the four-point marking ball fixing plate 303 is arranged in the middle of the second connecting rod 302 and is provided with four cantilevers, the tail end of each cantilever is provided with one optical marking ball 304, and the distance between every two adjacent optical marking balls 304 is larger than 4 cm; the dental implant handpiece 4 is used for performing cavity preparation and is clamped by the clamping and positioning tool 3 at the tail end of the flange plate of the mechanical arm; the fork-shaped tool 5 is provided with four cantilevers extending from the center in four different directions, the tail end of each cantilever is provided with an optical marking ball 501, the distance between every two adjacent optical marking balls 501 is more than 4cm, and the center of the fork-shaped tool 5 is vertically abutted against the turning needle 41 of the dental implant handpiece 4 before operation for providing the accurate position of the turning needle 41; the near infrared optical positioning system 6 is used for acquiring the position information of each optical marker ball in real time and determining the positions of the oral cavity of a patient, the tail end of the six-freedom-degree mechanical arm and the needle point of a machine needle 41 of the dental implant mobile phone; the operation navigation control system 7 is used for receiving the position information sent by the near-infrared optical positioning system in real time, performing oral image segmentation and three-dimensional reconstruction, and performing visualized path planning and motion control, thereby realizing operation navigation in the operation.

The following is a calibration method of the dental implantation robot system with optical navigation in this embodiment, including the following steps:

s1, obtaining the conversion relation between the coordinate system of the robot base and the coordinate system of the tail end of the six-degree-of-freedom mechanical arm according to the internal parameters of the robot; calculating unit vectors from an initial pose to an offset pose of the six-degree-of-freedom mechanical arm to obtain conversion relations between a robot base coordinate system and a near-infrared optical positioning system coordinate system, between a six-degree-of-freedom mechanical arm tail end coordinate system and a near-infrared optical positioning system coordinate system, and between a dental implant mobile phone coordinate system and a near-infrared optical positioning system coordinate system; which comprises the following steps:

s101, controlling the tail end of a six-degree-of-freedom mechanical arm to respectively move forwards in unit along three coordinate axes of a robot base coordinate system by taking any one optical mark point on a clamping and positioning tool at the tail end of a mechanical arm flange plate as a reference; capturing the positions of the optical mark points before and after movement by the near-infrared optical positioning system, and calculating a unit vector of the tail end of the six-degree-of-freedom mechanical arm from an initial pose to an offset pose under a near-infrared optical positioning system coordinate system to obtain a conversion relation between a robot base coordinate system and a near-infrared optical positioning system coordinate system;

s102, controlling the tail end of the six-degree-of-freedom mechanical arm to respectively perform single-position forward motion along three coordinate axes of a coordinate system at the tail end of the six-degree-of-freedom mechanical arm by taking any one optical mark point on the clamping and positioning tool at the tail end of the flange plate of the mechanical arm as a reference; capturing the positions of the optical mark points before and after movement by the near-infrared optical positioning system, and calculating a unit vector of the tail end of the six-degree-of-freedom mechanical arm from an initial pose to an offset pose under a coordinate system of the near-infrared optical positioning system to obtain a rotation matrix of the coordinate system of the tail end of the six-degree-of-freedom mechanical arm and the coordinate system of the near-infrared optical positioning system;

s103, clamping any three optical mark points on the positioning tool by using the tail end of the flange plate of the mechanical arm to establish a coordinate system of the dental implant mobile phone; the near-infrared optical positioning system captures the position information of the three optical mark points when the six-degree-of-freedom mechanical arm reaches the initial pose, and the conversion relation between the coordinate system of the teething implanting mobile phone and the coordinate system of the near-infrared optical positioning system is calculated.

S2, solving the conversion relation between the dental implant mobile phone coordinate system and the dental implant mobile phone needle tail end coordinate system by using singular value decomposition based on the conversion relation between the dental implant mobile phone coordinate system and the near infrared optical positioning system coordinate system; which comprises the following steps:

s201, placing a fork-shaped tool at the needle point of a machine needle of a dental implant mobile phone, and capturing the positions of four optical mark points on the fork-shaped tool by a near-infrared optical positioning system;

s202, based on a conversion relation between a dental implant mobile phone coordinate system and a near-infrared optical positioning system coordinate system, converting position information of the four optical mark points in the near-infrared optical positioning system coordinate system into position information in the dental implant mobile phone coordinate system;

s203, establishing a dental implant handpiece needle end coordinate system by using any three optical marking points on the forked tool, and solving a conversion relation between the dental implant handpiece coordinate system and the dental implant handpiece needle end coordinate system by using a singular value decomposition method based on the position information of the four optical marking points in the dental implant handpiece coordinate system.

S3, calculating a conversion relation between the dental implant mobile phone needle tail end coordinate system and the near infrared optical positioning system coordinate system based on the conversion relation between the dental implant mobile phone coordinate system and the near infrared optical positioning system coordinate system and between the dental implant mobile phone coordinate system and the dental implant mobile phone needle tail end coordinate system; which comprises the following steps:

s301, establishing a conversion relation between any point in the operation space and position information under a coordinate system of a near infrared optical positioning system under a dental implant mobile phone car needle tail end coordinate system:

wherein, P_oAnd P_pRespectively represents the position information of the point under the coordinate system of the dental implant mobile phone needle end and the coordinate system of the near infrared optical positioning system, R_poAnd T_poRespectively representing a rotation matrix and a translation matrix R between a dental implant mobile phone car needle tail end coordinate system and a near infrared optical positioning system coordinate system_toAnd T_toRespectively representing a rotation matrix and a translation matrix R between a dental implant mobile phone coordinate system and a near-infrared optical positioning system coordinate system_ptAnd T_ptRespectively representing a rotation matrix and a translation matrix of a tooth implantation mobile phone needle tail end coordinate system and a tooth implantation mobile phone coordinate system;

and S302, calculating a conversion relation between the coordinate system of the tail end of the dental implant mobile phone needle and the coordinate system of the near-infrared optical positioning system by using the conversion relation established in the S301.

S4, based on the conversion relation between a robot base coordinate system and a six-degree-of-freedom mechanical arm tail end coordinate system, between the six-degree-of-freedom mechanical arm tail end coordinate system and a tooth implantation mobile phone coordinate system, and between the tooth implantation mobile phone coordinate system and a tooth implantation mobile phone car needle tail end coordinate system, the near-infrared optical positioning system captures the positions of any three optical mark points on the clamping and positioning tool at the tail end of the flange of the mechanical arm in real time, the conversion relation between the tooth implantation mobile phone coordinate system and the near-infrared optical positioning system coordinate system is solved in real time by utilizing singular value decomposition, and the conversion relation between all coordinate systems in a closed loop is updated.

Before operation, calibration is carried out by using steps S1-S3, and when the relative position of the surgical robot and the near-infrared optical positioning system is changed, the conversion relation of the closed loop is updated by using step S4, so that a new round of calibration is completed.

The following is an application flow of the calibration method of the dental implantation robot system with optical navigation in dental implantation surgery in this embodiment, including:

the method comprises the following steps: the patient wears an optical position tracer to carry out CT scanning, the obtained CT image is subjected to image segmentation and other processing, and three-dimensional reconstruction is carried out on an operation navigation control system;

step two: planning a path on a three-dimensional visual interface on the operation navigation control system, setting a needle movement track, a safety point and a target point, and avoiding important tissues such as nerves, blood vessels and the like in dental pulp;

step three: establishing a hand-eye cooperative relationship between the six-degree-of-freedom mechanical arm and the near-infrared optical positioning system by using a calibration method; using a fork-shaped tool to register the tool, and determining the needle body direction of the machine needle and the spatial position of the needle point under a robot base coordinate system;

step four: the operation navigation control system realizes the matching of the image space and the operation space and sends an instruction to the operation robot through five optical marker balls on the optical position tracer;

step five: the six-degree-of-freedom mechanical arm drives the held tooth implanting mobile phone to move right above teeth of the target area, a safety point is reached, the needle point position and the needle body direction of the lathe needle are accurately adjusted, and the tail end of the six-degree-of-freedom mechanical arm reaches a target point along the needle body direction.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.