Ophthalmologic operation three-dimensional simulation system

Abstract

The invention relates to an ophthalmologic operation three-dimensional simulation system in the technical field of ophthalmologic operation simulation. The ophthalmologic operation three-dimensional simulation system comprises a force feedback device, a control center and a display terminal, the display terminal is used for displaying a simulated operating room scene; a force feedback system runs in the control center; the force feedback system comprises a data receiving module, an instrument positioning module, a data arrangement module, a data processing module and a data output module; the force feedback device comprises a sensing instrument, an operating arm and a fixing mechanism; the virtual display technology is combined with the feedback technology, real scene simulation of the ophthalmologic operation is achieved, various eyeballs of different specifications are arranged in the control center, an operator can modify eyeball parameters at any time so as to practice different ophthalmologic operations, various eyeball models do not need to be prepared, and the operation efficiency is improved. And abrasion of the eyeball model caused by long-term training is avoided, so that the training effect and repeatability are improved.

Description

Technical Field

[0001] The invention relates to the technical field of ophthalmic surgery simulation, and in particular to a three-dimensional simulation system for ophthalmic surgery. Background Art

[0002] At present, the eyeball operation simulation structure for ophthalmic surgery used for teaching has a single function and cannot simulate the operation of the eyeball in real ophthalmic surgery. The existing ophthalmic surgery eyeball operation simulation structure generally uses special materials to simulate the human eyeball, and the simulation of ophthalmic surgery is realized through the operator's real-life operation. However, due to personal physical reasons, this method is difficult to simulate all eyeball structures, and it cannot simulate all eyeballs with lesions. In addition, the cumbersomeness of making simulations and the wear of eyeball models during training and teaching make this simulation operation not only time-consuming, labor-intensive and costly, but also not very ideal.

[0003] In order to solve the above problems, the present invention realizes the real-life simulation of ophthalmic surgery through the combination of virtual display technology and force feedback technology. By setting a variety of eyeballs of different specifications in the control center, the operator can modify the eyeball parameters at any time to practice different ophthalmic surgeries. There is no need to prepare various eyeball models, and the wear of the eyeball models caused by long-term training is avoided, thereby improving the training effect and repeatability. Summary of the invention

[0004] In order to solve the above problems, the present invention discloses a three-dimensional simulation system for ophthalmic surgery. The technical solution of the present invention is implemented as follows:

[0005] A three-dimensional simulation system for ophthalmic surgery, comprising a force feedback device, a control center and a display terminal;

[0006] The force feedback device is connected to the control center via wired or wireless means and is controlled by the control center;

[0007] The display terminal is connected to the control center;

[0008] The display terminal is used to display a simulated operating room scene;

[0009] A force feedback system operates in the control center;

[0010] The force feedback system includes a data receiving module, an instrument positioning module, a data sorting module, a data processing module and a data output module;

[0011] The force feedback device comprises a touch instrument, an operating arm and a fixing mechanism;

[0012] The sensing device is arranged at the terminal end of the operating arm, and the operating arm is connected and fixed to the fixing mechanism;

[0013] The data receiving module and the instrument positioning module are used to receive information from the sensing instrument and the operating arm;

[0014] The data sorting module is used to receive the information from the data receiving module and perform pre-processing;

[0015] The data processing module is used to receive information from the data sorting module and determine whether the operator of the force feedback device has made an operation error;

[0016] The data output module is used to output the information processed by the data processing module;

[0017] Preferably, the sensing instrument includes a simulated scalpel, simulated surgical tweezers, simulated surgical forceps, a simulated phacoemulsification handle, a simulated lens syringe, simulated capsulorhexis forceps, a disinfectant swab, and a simulated corneal knife.

[0018] Preferably, the force feedback device is provided with a force sensor, a displacement sensor, an angle sensor and a controller; a force feedback algorithm runs in the controller; the force feedback algorithm calculates the operator's real-time instrument operation force and direction based on the information of the force sensor, the displacement sensor and the angle sensor and controls the force feedback of the force feedback device, and the controller simultaneously transmits the operator's real-time instrument operation force and direction to the data receiving module.

[0019] Preferably, the force feedback algorithm includes proportional calculation, integral calculation and differential calculation;

[0020] The ratio calculation is based on the deviation signal between the actual force fed back by the force sensor and the preset target force. The specific formula is as follows:

[0021] P out =K p ·e(t);

[0022] In the above formula, P out is the output of the proportional part, K p is the proportional gain, e(t) is the error signal at the current moment;

[0023] The integral calculation is to integrate the error signal to eliminate the static error of the system. The specific formula is as follows:

[0024]

[0025] In the above formula, I out is the output of the integral part, K i is the integral gain, is the integral of the error signal from 0 to the current time t;

[0026] The differential part calculates the control input based on the rate of change of the error signal. The specific formula is as follows:

[0027]

[0028] In the above formula, D out is the output of the differential part, K d is the differential gain, is the rate of change of the error signal;

[0029] The formula of the force feedback algorithm is:

[0030]

[0031] In the above formula, u(t) is the total output of the controller.

[0032] Preferably, the display terminal includes VR glasses and a display screen.

[0033] Preferably, the control center and the display screen are integrated, and the control center is provided with an operating console.

[0034] Preferably, the data processing module includes surgical operation procedures and right and wrong judgments;

[0035] The correctness judgment is: judging whether the operator has made an operation error based on the trajectory and force of the current operator when operating the sensing instrument; if not, entering the next step of the surgical operation process, otherwise displaying an operation error on the display terminal.

[0036] Preferably, the control center includes several human models;

[0037] The human body model includes an eyeball model;

[0038] The eyeball model of each human model is provided with a different rebound coefficient and setback coefficient; the eyeball model is used to cooperate with the force feedback device to realize the simulation of the operator's surgical feel.

[0039] Preferably, it also includes a foot control device; the foot control device is connected to the control center via a wired or wireless method; the foot control device is used to achieve function switching of the surgical operation process.

[0040] Preferably, the data processing module uses a three-dimensional vector to represent the position of the surgical instrument and the eyeball, and the position formula is: p(t) = [x(t), y(t), z(t)] T ;

[0041] In the above formula, t is the time, p is the position of the object, x, y, z represent the spatial coordinates of the object, and T is;

[0042] The data processing module uses a three-dimensional vector to represent the force acting on the touch device and the eyeball model. The force formula is: F(t) = [Fx(t), Fy(t), Fz(t)] T ;

[0043] In the above formula, t is the time, F represents the total force on the object, and Fx, Fy and Fz represent the forces on the object in three-dimensional directions respectively.

[0044] The present invention realizes real-life simulation of ophthalmic surgery by combining virtual display technology with force feedback technology, and by setting eyeballs of various specifications in the control center, the operator can modify the eyeball parameters at any time to practice different ophthalmic surgeries, and there is no need to prepare various eyeball models, and the wear of the eyeball models caused by long-term training is avoided, thereby improving the training effect and repeatability. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only one embodiment of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0046] The same parts are denoted by the same reference numerals. It should be noted that the words "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to directions in the drawings, and the words "bottom" and "top", "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively.

[0047] Figure 1 It is a structural schematic diagram of an embodiment of a three-dimensional simulation system for ophthalmic surgery;

[0048] Figure 2 for Figure 1 A structural diagram of a force feedback device in the embodiment shown;

[0049] Figure 3 for Figure 2 The structural diagram of the touch device in the force feedback device shown;

[0050] Figure 4 for Figure 1 The operation flow diagram of the embodiment shown is as follows.

[0051] In the above drawings, the meanings of the symbols of the reference numerals are as follows:

[0052] 1. Force feedback device;

[0053] 1-1, touch device;

[0054] 1-2, operating arm;

[0055] 1-3, fixed mechanism;

[0056] 2. Display terminal;

[0057] 3. Control center;

[0058] 4. Foot switch. DETAILED DESCRIPTION

[0059] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0060] Unless otherwise defined, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by technicians in the technical field to which the present invention belongs; the terms used in the specific implementation methods are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" in the specification and claims of the present invention and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0061] In the description of the specific implementation methods of the present invention, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present invention, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0062] Reference to "embodiments" in the present invention means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in the present invention may be combined with other embodiments.

[0063] In the description of the embodiments of the present invention, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present invention generally indicates that the associated objects before and after are in an "or" relationship.

[0064] Throughout the present invention, numerical values ​​represent approximate measures or limits of ranges to cover minor deviations from given values ​​as well as embodiments with about the values ​​mentioned and embodiments with the exact values ​​mentioned. Except for the working examples provided at the end of the detailed description, all numerical values ​​of parameters (e.g., amounts or conditions) in this specification (including the appended claims) should be understood as modified by the term "about" in all cases, regardless of whether "about" actually appears before the numerical value. "About" indicates that the stated numerical value allows some minor imprecision (close to the exact value of the value to some extent; approximately or reasonably close to the value; almost). If the imprecision provided by "about" is not otherwise understood in this ordinary sense in the art, "about" as used in the present invention at least indicates the variation that can be produced by the ordinary methods of measuring and using such parameters. For example, "about" may include a variation of less than or equal to 5%, optionally less than or equal to 4%, optionally less than or equal to 3%, optionally less than or equal to 2%, optionally less than or equal to 1%, optionally less than or equal to 0.5%, and in some aspects, optionally less than or equal to 0.1%.

[0065] Additionally, disclosure of ranges includes disclosure of all values ​​within the entire range and further divided ranges, including endpoints and sub-ranges given for such ranges.

[0066] The embodiments of the present invention will be described in more detail below by way of examples. It should be noted that the embodiments of the present invention are not limited to these examples.

[0067] Example

[0068] In a specific embodiment, Figure 1As shown, a three-dimensional simulation system for ophthalmic surgery includes a force feedback device 1, a control center 3, a display terminal 2 and a foot switch 4; the force feedback device 1 is connected to the control center 3 in a wired or wireless manner and is controlled by the control center 3; the display terminal 2 is connected to the control center 3; the display terminal 2 is used to display a simulated operating room scene; a force feedback system runs in the control center 3; the force feedback system includes a data receiving module, an instrument positioning module, a data sorting module, a data processing module and a data output module; the force feedback device 1 includes a sensing instrument 1-1, an operating arm 1-2 and a fixing mechanism 1-3; the sensing instrument 1-1 is arranged at the terminal of the operating arm 1-2, and the operating arm 1-2 is connected and fixed to the fixing mechanism 1-3; the data receiving module and the instrument positioning module are used to receive information from the sensing instrument 1-1 and the operating arm 1-2; the data sorting module is used to receive information from the data receiving module and perform preprocessing; the data processing module is used to receive information from the data sorting module and determine whether the operator of the force feedback device 1 has made an operating error; the data output module is used to output the information processed by the data processing module. The control center 3 includes several human models; the human models include eyeball models; the eyeball models of each human model are set with different rebound coefficients and setback coefficients; the eyeball models are used to cooperate with the force feedback device 1 to realize the operator's surgical feel simulation. The foot switch 4 is connected to the control center 3 by wire or wirelessly; the foot switch 4 is used to realize the function of the surgical operation process and the switching of the touch device.

[0069] The sensing instrument 1-1 includes a simulated scalpel, simulated surgical tweezers, simulated surgical forceps, a simulated ultrasonic emulsification handle, a simulated lens syringe, a simulated capsulorhexis forceps, a disinfection swab, and a simulated corneal knife.

[0070] The force feedback device 1 is equipped with a force sensor, a displacement sensor, an angle sensor and a controller; a force feedback algorithm runs in the controller; the force feedback algorithm calculates the operator's real-time instrument operation force and direction based on the information of the force sensor, the displacement sensor and the angle sensor and controls the force feedback of the force feedback device 1. The controller also transmits the operator's real-time instrument operation force and direction to the data receiving module.

[0071] The force feedback algorithm includes proportional calculation, integral calculation and differential calculation;

[0072] Among them, the proportional calculation is based on the deviation signal between the actual force fed back by the force sensor and the preset target force. The specific formula is as follows:

[0073] P out =K p ·e(t);

[0074] In the above formula, P out is the output of the proportional part, K pis the proportional gain, e(t) is the error signal at the current moment;

[0075] The integral calculation is to integrate the error signal to eliminate the static error of the system. The specific formula is as follows:

[0076]

[0077] In the above formula, I out is the output of the integral part, K i is the integral gain, is the integral of the error signal from 0 to the current time t;

[0078] The differential part calculates the control input based on the rate of change of the error signal. The specific formula is as follows:

[0079]

[0080] In the above formula, D out is the output of the differential part, K d is the differential gain, is the rate of change of the error signal;

[0081] The formula of the force feedback algorithm is:

[0082]

[0083] In the above equation, u(t) is the total output of the controller, which is used to adjust the control input of the system to track the desired set point.

[0084] In this embodiment, the force feedback device 1 realizes real-time perception and feedback of hand force in simulated operation through precise sensors and algorithms. The main algorithm is PID control algorithm. In the force feedback device 1, the PID algorithm can realize precise control of simulated force by adjusting proportional, integral and differential parameters according to the deviation between the actual force fed back by the sensor and the preset target force.

[0085] The PID control algorithm is a commonly used feedback control algorithm that calculates the control input based on the system's error signal (i.e., the deviation between the actual output and the desired output), thereby adjusting the system's output to track the desired set point. The relevant formulas of the PID control algorithm mainly include the calculation of the three parts of proportion (P), integral (I) and differential (D).

[0086] In this embodiment, the proportional gain K is adjusted p , integral gain K i and differential gain K d , different control performance and response characteristics can be achieved.

[0087] The data processing module includes the surgical operation process and right and wrong judgment; the right and wrong judgment is: based on the trajectory and force of the current operator when operating the sensing instrument 1-1, determine whether the operator has made an operation error; if not, enter the next step of the surgical operation process, otherwise display the operation error on the display terminal 2.

[0088] In this embodiment, the force feedback device 1 has a force feedback simulation function, which can convert mechanical signals into electrical signals. The force feedback device 1 can sense and calculate the strength, direction and angle of the user's hand in the simulated operation in real time. When the user uses surgical instruments to operate on the simulator, the force feedback device 1 will respond immediately to simulate the interaction force between the surgical instruments and different anatomical structures of the eye. This force feedback not only includes the contact force between the instrument and the surface of the eyeball, but also covers the penetration resistance and cutting force of the instrument in different eye tissues.

[0089] The tactile device can simulate 6 degrees of freedom of motion and force feedback, which means that the force feedback device 1 can fully simulate the motion of the hand during the operation, including complex movements such as up and down, left and right, front and back, and rotation. This multi-dimensional motion and force feedback makes the simulation operation more delicate and accurate. With the display terminal 2 and other devices, the operator feels as if he is in a real surgical environment.

[0090] The touch device is used to simulate the operation of the instrument during the operation. The touch device moves, and the force feedback device 1 transmits the simulated operation to the control center 3 through signal conversion. The control center 3 processes the data and displays the operator's touch device operation on the display terminal 2, simulating the movement trajectory and force of the surgical tool, thereby realizing the simulated operation of the ophthalmic surgery. In this embodiment, the touch device is designed to be detachable. This embodiment prepares a variety of different touch devices, such as simulated scalpels, simulated surgical tweezers, simulated surgical forceps, simulated phacoemulsification handles, simulated crystal injectors, simulated capsulorhexis forceps, disinfected swabs, and simulated corneal knives. The operator can simulate different surgical tools by replacing different touch devices. In addition, in order to further improve the effect of force feedback and make the operator more immersive when performing simulated surgery, the force feedback system in the present invention sets different feedback parameters according to different touch devices. Through the feedback adjustment of the force feedback device 1, the operator obtains force feedback corresponding to the corresponding touch device when using each touch device.

[0091] In this embodiment, the foot switch can be used to switch on and off the functions of some instruments during the operation, control the opening and closing of the functions of the simulation tools in the screen, perform operations such as suction on the eye tissue structure, and perform ophthalmic surgery simulation operations.

[0092] The foot switch is connected to the control center 3 by wired connection. The depth and duration of stepping on the pedal can achieve precise control of the simulated surgical instrument and simulate the real surgical operation experience.

[0093] In this embodiment, a complete set of ophthalmic surgery simulation operation contents is provided in the control center 3, and the user can simulate the entire ophthalmic surgery learning process such as simulated surgery selection, simulated surgery operation, simulated surgery evaluation and viewing.

[0094] With the cooperation of various modules, the eyeball model will produce corresponding changes and movements when the touch device of the force feedback device 1 moves, such as being dragged and rotated, squeezed and deformed, cut, etc. The eyeball structure is constructed according to the actual eye data of clinical cataract cases, and corresponding adjustments and designs are made for surgical simulation presentation and interaction. It has a complete eye anatomical structure and various tissue structure characteristics. The simulated surgical tools are designed according to the commonly used and special instruments for ophthalmic surgery. Their physical properties are reproduced in the program, and the complete operation and function of the instruments can be performed. The simulated surgical tools correspond to the shape of the touch device one by one.

[0095] The display terminal 2 can display a three-dimensional image of a simulated surgical tool and a computer model of a tissue based on physics, including a microscope observation angle and a normal angle. The operator can observe through the microscope eyepiece while operating, and the visual display terminal 2 will display an enlarged microscope operation screen. The display terminal 2 also includes a console, through which the operator communicates with the control center 3: for example, selecting the surgical content to be practiced, checking surgical related information before starting, viewing feedback content, etc.

[0096] The microscope eyepiece referred to in the present invention refers to the simulation of the microscope observation viewing angle on the display screen.

[0097] In the present invention, the data processing module uses a three-dimensional vector to represent the position of the surgical instrument and the eyeball, and the position formula is: p(t) = [x(t), y(t), z(t)] T ;

[0098] In the above formula, t is the time, p is the position of the object, x, y, z represent the spatial coordinates of the object, and T is;

[0099] The data processing module uses a three-dimensional vector to represent the force acting on the touch device 1-1 and the eyeball model. The force formula is: F(t) = [Fx(t), Fy(t), Fz(t)] T ;

[0100] In the above formula, t is the time, F represents the total force on the object, and Fx, Fy and Fz represent the forces on the object in three-dimensional directions respectively.

[0101] In the present invention, in order to simulate the real surgical effect, two force feedback devices 1 are provided for the operator to operate with his left and right hands. When the operator operates the touch instrument 1-1 through the force feedback device 1, the data receiving module in the control center 3 receives mechanical information from the two force feedback devices 1, and the mechanical information includes the movement trajectory and force information of the touch instrument 1-1. At the same time, the data preprocessing module will perform instrument positioning, that is, the simulated positioning of the touch instrument 1-1 operated by the operator in the simulated surgical scene.

[0102] The data preprocessing module will organize and summarize the above information, such as the information data of the sensing device 1-1, the position data of the sensing device 1-1, and the magnitude of the force of the sensing device 1-1, and divide the force into a setback coefficient and a rebound coefficient and transmit them to the data processing module.

[0103] The data processing module will process the above information to different degrees. First, the usage data of the sensing device 1-1 will be judged, and the data will be compared with the preset sensing device 1-1 that should be used in each step. If it is correct, it will proceed to the next step of judgment. If it is wrong, an error prompt will be fed back to remind the operator to replace the sensing device 1-1. Then the position of the instrument will be judged, and it will be compared with the preset position information of the sensing device 1-1. If it is correct, it will be fed back to the next step of operation. In addition, the kinetic energy formula will be used to calculate the force of the frustration coefficient and the rebound coefficient and feedback it to the force feedback device 1. After the data is processed, the force data will be transmitted to the force feedback device 1 separately, and the rest of the data will be uploaded to the data output module.

[0104] The data output module will finally feed back the processed data to the display terminal 2, and finally present the data to the operator in the form of a graphic screen through the display terminal 2. Or use VR glasses to display it to the operator.

[0105] This embodiment simulates the real internal structure of the eyeball. Different eyeballs have different internal structures and different materials when designed. For example, the material of the cornea is transparent and elastic. During the collision, a setback coefficient and a rebound coefficient will be generated. The system will convert these coefficients into parameters and feed them back to the force feedback device 1, and the force feedback device 1 will simulate the force. The lens in the eyeball is soft, inelastic, and easy to deform. When it collides with surgical tools, the feedback coefficient is very small and there is almost no force feedback. During the operation, various professional medical instruments are also used, such as ophthalmic scalpels, corneal knives, intraocular lens implanters, etc. These instruments are made of different materials, so in the real operation process, the force feedback obtained by using these instruments is also different. When designing the parameters of the touch instrument 1-1 and the force feedback, try to restore the real surgical instruments to obtain a more realistic operating feel. For example, in order to simulate real cataract surgery, the lens part in the eyeball model is specially processed in the control center 3 (referring to designing different references and different setback coefficients and rebound coefficients). When a force is applied to the lens, it will move in the direction of the force. The distance of the displacement depends on the magnitude of the force.

[0106] This embodiment can repeatedly perform ophthalmic surgical operation training.

[0107] It should be pointed out that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A three-dimensional simulation system for ophthalmic surgery, characterized in that: It includes a force feedback device, a control center and a display terminal; The force feedback device is connected to the control center via wired or wireless means and is controlled by the control center; The display terminal is connected to the control center; The display terminal is used to display a simulated operating room scene; A force feedback system operates in the control center; The force feedback system includes a data receiving module, an instrument positioning module, a data sorting module, a data processing module and a data output module; The force feedback device comprises a touch instrument, an operating arm and a fixing mechanism; The sensing device is arranged at the terminal end of the operating arm, and the operating arm is connected and fixed to the fixing mechanism; The data receiving module and the instrument positioning module are used to receive information from the sensing instrument and the operating arm; The data sorting module is used to receive information from the data receiving module and perform pre-processing; The data processing module is used to receive information from the data sorting module and determine whether the operator of the force feedback device has made an operation error; The data output module is used to output the information processed by the data processing module.

2. The ophthalmic surgery three-dimensional simulation system according to claim 1, characterized in that: The sensing instrument includes a simulated scalpel, simulated surgical tweezers, simulated surgical forceps, simulated phacoemulsification handle, simulated crystal syringe, simulated capsulorhexis forceps, a disinfection swab, and a simulated corneal knife.

3. The ophthalmic surgery three-dimensional simulation system according to claim 1, characterized in that: The force feedback device is provided with a force sensor, a displacement sensor, an angle sensor and a controller; a force feedback algorithm is run in the controller; the force feedback algorithm calculates the operator's real-time instrument operation force and direction based on the information of the force sensor, the displacement sensor and the angle sensor and controls the force feedback of the force feedback device, and the controller simultaneously transmits the operator's real-time instrument operation force and direction to the data receiving module.

4. The three-dimensional ophthalmic surgery simulation system according to claim 3, characterized in that: The force feedback algorithm includes proportional calculation, integral calculation and differential calculation; The ratio calculation is based on the deviation signal between the actual force fed back by the force sensor and the preset target force. The specific formula is as follows: P out =K p ·e(t); In the above formula, P out is the output of the proportional part, K p is the proportional gain, e(t) is the error signal at the current moment; The integral calculation is to integrate the error signal to eliminate the static error of the system. The specific formula is as follows: In the above formula, I out is the output of the integral part, K i is the integral gain, is the integral of the error signal from 0 to the current time t; The differential part calculates the control input based on the rate of change of the error signal. The specific formula is as follows: In the above formula, D out is the output of the differential part, K d is the differential gain, is the rate of change of the error signal; The formula of the force feedback algorithm is: In the above formula, u(t) is the total output of the controller.

5. The ophthalmic surgery 3D simulation system according to claim 1, characterized in that: The display terminal includes VR glasses and a display screen.

6. The three-dimensional ophthalmic surgery simulation system according to claim 5, characterized in that: The control center and the display screen are integrated, and the control center is provided with an operating console.

7. The three-dimensional ophthalmic surgery simulation system according to claim 1, characterized in that: The data processing module includes surgical operation procedures and right and wrong judgments; The correctness judgment is: judging whether the operator has made an operation error based on the trajectory and force of the current operator when operating the sensing instrument; if not, entering the next step of the surgical operation process, otherwise displaying an operation error on the display terminal.

8. The three-dimensional ophthalmic surgery simulation system according to claim 7, characterized in that: The control center includes several human models; The human body model includes an eyeball model; The eyeball model of each human model is provided with a different rebound coefficient and setback coefficient; the eyeball model is used to cooperate with the force feedback device to realize the simulation of the operator's surgical feel.

9. The three-dimensional ophthalmic surgery simulation system according to claim 8, characterized in that: It also includes a foot control device; the foot control device is connected to the control center via a wired or wireless method; the foot control device is used to achieve function switching of the surgical operation process.

10. The three-dimensional ophthalmic surgery simulation system according to claim 7, characterized in that: The data processing module uses a three-dimensional vector to represent the position of the surgical instrument and the eyeball. The position formula is: p(t) = [x(t), y(t), z(t)] T ; In the above formula, t is the time, p is the position of the object, x, y, z represent the spatial coordinates of the object, and T is; The data processing module uses a three-dimensional vector to represent the force acting on the touch device and the eyeball model. The force formula is: F(t) = [Fx(t), Fy(t), Fz(t)] T ; In the above formula, t is the time, F represents the total force on the object, and Fx, Fy and Fz represent the forces on the object in three-dimensional directions respectively.

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