Stomach tube intermittent placement teaching simulation device based on virtual reality

Abstract

The invention discloses a stomach tube intermittent placement teaching simulation device based on virtual reality, and relates to the technical field of stomach tube teaching equipment, and the stomach tube intermittent placement teaching simulation device comprises a VR all-in-one machine, handheld operation equipment and a VR computer; the VR all-in-one machine realizes real-time visual simulation of the virtual patient by displaying a three-dimensional view and a real-time physiological state of the virtual patient; the handheld operation device is used for simulating stomach tube insertion operation, a student interacts with a virtual patient through the handheld operation device, the handheld operation device comprises an operation handle and an induction module, and the induction module detects the operation strength, angle and speed of the student in real time and transmits the operation data to the virtual reality environment; the VR computer comprises a virtual patient intelligent state system, an augmented virtual reality feedback system, a machine learning adaptive nonlinear reaction system and a closed-loop feedback system; through virtual patient three-dimensional view and real-time physiological state simulation, more immersive learning experience is provided for students.

Description

Technical Field

[0001] The present invention relates to the technical field related to gastric tube teaching equipment, and in particular to a gastric tube intermittent insertion teaching simulation device based on virtual reality. Background Art

[0002] Gastric tube insertion, also known as gastric intubation, is mainly used to drain gastrointestinal contents through a gastrointestinal decompression tube or to feed liquid food through a gastric tube to patients who cannot eat orally, to ensure that the patient takes in enough nutrition, water and medicine to facilitate early recovery. For inexperienced medical staff, the insertion of a gastric tube is more difficult, and it is even more difficult to achieve better results. Therefore, a teaching simulation model is needed for practice.

[0003] However, existing teaching models are often simple in structure and have poor simulation effects on the internal structure of the human body, so the teaching practice effect is also poor. The most important thing is that people cannot observe the state of the gastric tube entering, which makes the teaching efficiency low. In addition, since the existing teaching models are static, they cannot simulate how this physiological change affects the gastric tube insertion process when the patient has a vomiting reaction. Summary of the invention

[0004] In order to solve the defects of the prior art, the present invention provides a teaching simulation device for intermittent gastric tube insertion based on virtual reality.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] The present invention provides a virtual reality-based teaching simulation device for intermittent gastric tube insertion, comprising:

[0007] VR all-in-one devices, handheld operating devices and VR computers;

[0008] The VR all-in-one machine realizes real-time visual simulation of a virtual patient by displaying a three-dimensional view and real-time physiological status of the virtual patient, wherein the three-dimensional view of the virtual patient includes dynamic changes of various parts of the virtual patient;

[0009] The handheld operating device is used to simulate the gastric tube insertion operation. The trainee interacts with the virtual patient through the handheld operating device. The handheld operating device includes an operating handle and a sensing module. The sensing module detects the trainee's operating force, angle and speed in real time, and transmits these operating data to the virtual reality environment for synchronizing the virtual patient's response.

[0010] The VR computer includes a virtual patient intelligent state system, an augmented virtual reality feedback system, a machine learning adaptive nonlinear response system, and a closed-loop feedback system;

[0011] The virtual patient intelligent state system generates feedback of the virtual patient based on the simulated data, so as to simulate the changes of the physiological state of the virtual patient;

[0012] The visual substitution tactile feedback module, virtual resistance display module and sound feedback module of the augmented virtual reality feedback system improve the trainees' operation accuracy and immersion;

[0013] The machine learning adaptive nonlinear response system adjusts the physiological response of the virtual patient according to the trainee's operation behavior;

[0014] The closed-loop feedback system adjusts the physiological response and feedback content of the virtual patient in real time based on the trainee's operation data and the physiological response of the virtual patient.

[0015] As a preferred technical solution of the present invention, the VR all-in-one machine is a virtual reality head mounted display with an independent processor, and a basic environment for virtual reality operation of the VR all-in-one machine is constructed by installing a VR operating system;

[0016] The VR all-in-one machine provides software drivers for the handheld operating device by installing a VR interactive SDK. The trainees send sensing or control instructions to the virtual reality scene through the handheld operating device, and the virtual scene feeds back the somatosensory experience and acts on the trainees through the handheld operating device.

[0017] As a preferred technical solution of the present invention, the VR all-in-one machine and the handheld operating device are also provided with a motion tracking system, which is used to track the trainee's head and hand movements in real time. The motion tracking system includes a number of sensor modules, which synchronize the trainee's movements to the virtual reality environment in real time by sensing the position, direction and movement speed of the trainee's head and hands, thereby reflecting the interaction process between the trainee and the virtual patient.

[0018] As a preferred technical solution of the present invention, the virtual patient intelligent state system includes:

[0019] A virtual patient generation module is used to generate virtual patients and collect the body position changes of virtual patients in real time;

[0020] Physiological state change simulation module, which dynamically simulates the virtual patient's gastric movement, reflux and discomfort reaction according to the virtual patient's physiological data;

[0021] The virtual patient feedback module generates virtual feedback according to the changes in the virtual patient's physiological state, simulating the gastric reaction, muscle contraction and discomfort during the insertion of the gastric tube.

[0022] As a preferred technical solution of the present invention, the virtual patient generation module simulates the changes in the virtual patient's body position through a virtual skeleton and joint motion model, and captures the position and posture of the virtual patient in three-dimensional space in real time.

[0023] As a preferred technical solution of the present invention, the physiological state change simulation module includes a biomechanical model and a physical engine;

[0024] The biomechanical model includes simulating the elastic coefficient of the stomach wall using the Mooney-Rivlin model, simulating the damping coefficient using the Voigt model, and simulating the contraction frequency using a periodic external force function;

[0025] The physics engine uses Unity or Unreal engine.

[0026] As a preferred technical solution of the present invention, the machine learning adaptive nonlinear response system includes:

[0027] Trainee operation data collection module collects trainee operation data in real time;

[0028] Adaptive algorithm analysis module, which analyzes operation data through machine learning algorithms and determines the characteristics of students' operations;

[0029] The virtual patient physiological response adjustment module adjusts the virtual patient's physiological response according to the trainee's operating characteristics.

[0030] As a preferred technical solution of the present invention, the adaptive algorithm analysis module uses a machine learning algorithm to analyze the student's operation characteristics and is expressed by the following formula:

[0031]

[0032] Among them, F(t) represents the strength of the trainee's operation, θ(t) represents the trainee's operation angle, v(t) represents the trainee's operation speed, d(t) represents the directionality of the trainee's operation, α1, α2, α3, and α4 are weight coefficients, which are adjusted according to the trainee's operation data, and β1, β2, β3, and β4 are nonlinear exponents, which represent the nonlinear relationship between each operation parameter and the virtual patient's response.

[0033] As a preferred technical solution of the present invention, the closed-loop feedback system includes:

[0034] Data comparison and feedback calculation module, which compares the trainee's operation data with the physiological response of the virtual patient in real time and calculates feedback data;

[0035] A real-time adjustment module dynamically adjusts the virtual patient's physiological state and operation feedback according to the comparison results;

[0036] The training difficulty adjustment module automatically adjusts the training content and feedback details according to the students' performance to provide a personalized training experience.

[0037] As a preferred technical solution of the present invention, the augmented virtual reality feedback system includes a visual substitution tactile feedback module, a virtual resistance display module and a sound feedback module, which are used to improve the trainees' operation accuracy and immersion.

[0038] The beneficial effects of the present invention are:

[0039] 1. The present invention can dynamically display the physiological reactions of virtual patients, especially the physiological changes during the insertion of gastric tubes, through the three-dimensional view of virtual patients and real-time physiological state simulation. Trainees can intuitively observe physiological reactions such as gastric movements through virtual reality (VR) technology, which breaks through the problem that traditional models are not realistic enough in simulating the internal structure of the human body. In particular, the simulation of the gastric tube entry state can be displayed, which provides trainees with a more immersive learning experience and enables them to better master complex operating skills.

[0040] 2. In the present invention, by setting up a virtual patient generation module and a physiological state change simulation module, the virtual patient can adjust the body position, gastric reaction and other physiological states in real time according to the changes in the trainees' operations. This function effectively solves the defect that the traditional model cannot display the dynamic reaction of the human body, allowing trainees to experience a more realistic operation process, thereby enhancing the teaching effect.

[0041] 3. In the present invention, an enhanced virtual reality feedback system is provided, especially a virtual resistance display module and a visual substitution tactile feedback module. When performing a gastric tube insertion operation, trainees can feel the simulated resistance and tactile feedback from a virtual patient, so that trainees can better adapt to the physiological changes of the patient, especially in complex situations such as vomiting reactions. The system can make timely adjustments according to the physiological changes of the patient, so that trainees can master the ability to cope with complex situations in a simulated environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0043] Figure 1 The present invention is a system flow chart of the gastric tube intermittent insertion teaching simulation device. DETAILED DESCRIPTION

[0044] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0045] Embodiment 1

[0046] like Figure 1 As shown, a virtual reality-based gastric tube intermittent insertion teaching simulation device comprises:

[0047] VR all-in-one devices, handheld operating devices and VR computers;

[0048] The VR all-in-one machine realizes real-time visual simulation of virtual patients by displaying the three-dimensional view and real-time physiological status of virtual patients. The three-dimensional view of virtual patients includes dynamic changes of various parts of the virtual patients. Trainees observe the physiological reactions of virtual patients, including gastric movements and discomfort reactions, through changes in the field of view.

[0049] The VR all-in-one machine is the core interactive terminal of the entire system, responsible for providing visual immersion and real-time physiological simulation. Its main functions include:

[0050] 3D dynamic display of virtual patients: 3D modeling technology is used to present complete virtual patients, including skin, muscles, digestive tract and other anatomical structures, to enhance the realism of medical teaching;

[0051] Physiological state simulation: The physiological response of the virtual patient (such as gastric peristalsis) is adjusted in real time based on the trainee's operation dynamics to improve the authenticity of the training;

[0052] Free perspective interaction: Students can observe the changes in physiological structures from different angles in the VR field of view, such as the path of the gastric tube entering the esophagus and whether it touches the trachea.

[0053] The handheld operating device is used to simulate the gastric tube insertion operation. The trainee interacts with the virtual patient through the handheld operating device. The handheld operating device includes an operating handle and a sensing module. The sensing module detects the trainee's operating force, angle and speed in real time, and transmits these operating data to the virtual reality environment for synchronizing the virtual patient's response.

[0054] The handheld operating device is used to simulate the actual gastric tube insertion process, allowing trainees to practice techniques and master operating skills in a virtual environment. It mainly includes the following components:

[0055] Operating handle: simulates the actual feel of the gastric tube, provides physical feedback for holding and pushing, and ensures that the operating habits are consistent with the clinical practice.

[0056] Sensing module: The sensor detects the operation force, angle, insertion speed and other data, and feeds them back to the virtual reality environment in real time to determine the physiological response of the virtual patient.

[0057] Force feedback technology: provides appropriate resistance when encountering anatomical resistance (such as colliding with the epiglottis or the esophageal entrance), making the training more realistic.

[0058] The VR computer includes a virtual patient intelligent state system, an augmented virtual reality feedback system, a machine learning adaptive nonlinear response system and a closed-loop feedback system; the VR computer is the data processing center of the entire system and includes four core modules.

[0059] The virtual patient intelligent state system generates feedback of the virtual patient based on the simulated data, so as to simulate the changes of the physiological state of the virtual patient;

[0060] The visual substitution tactile feedback module, virtual resistance display module and sound feedback module of the augmented virtual reality feedback system improve the trainees' operation accuracy and immersion;

[0061] The machine learning adaptive nonlinear response system adjusts the physiological response of the virtual patient according to the trainee's operation behavior;

[0062] The closed-loop feedback system adjusts the physiological response and feedback content of the virtual patient in real time based on the trainee's operation data and the physiological response of the virtual patient.

[0063] The present invention can dynamically display the physiological reactions of virtual patients, especially the physiological changes during the insertion of gastric tubes, through the three-dimensional view of virtual patients and real-time physiological state simulation. Trainees can intuitively observe physiological reactions such as gastric movements through virtual reality (VR) technology, which breaks through the problem that traditional models are not realistic enough in simulating the internal structure of the human body. In particular, the simulation of the gastric tube entry state can be displayed, which provides trainees with a more immersive learning experience and enables them to better master complex operating skills.

[0064] Furthermore, the VR all-in-one machine is a virtual reality head mounted display with an independent processor, and a basic environment for virtual reality operation of the VR all-in-one machine is constructed by installing a VR operating system;

[0065] VR all-in-one machines build a virtual reality environment by installing a VR operating system. This operating system provides the basic framework for running virtual reality applications. Specific functions include:

[0066] Virtual environment rendering: The operating system drives the GPU through an independent processor to render the virtual scene and generate realistic three-dimensional images;

[0067] User input management: The operating system processes input signals from the user, including head movements, hand movements, and interactive instructions from handheld devices, ensuring that the user's actions are responded to in a timely manner in the virtual environment;

[0068] Multitasking and optimization: The operating system manages the various resources of the VR all-in-one machine to ensure that tasks such as rendering, input, and data synchronization can be performed efficiently.

[0069] The VR all-in-one machine provides software drivers for the handheld operating device by installing the VR interactive SDK. The trainee sends sensing or control instructions to the virtual reality scene through the handheld operating device, and the virtual scene feedbacks the somatosensory experience and acts on the trainee through the handheld operating device;

[0070] Handheld devices are the main tools for students to interact with virtual reality. Common handheld devices include VR controllers, handles or other customized devices. These devices are equipped with multiple sensors, such as accelerometers, gyroscopes, touch sensors, buttons, etc., to capture students' input actions and transmit them to the virtual reality environment. Handheld devices usually have the following functions:

[0071] 3D spatial positioning: The handheld device determines its position and orientation in three-dimensional space through built-in sensors and external tracking systems, so that the student's hand movements can be accurately mapped to the virtual scene;

[0072] Button and touch interaction: Buttons, touch screens or touchpads on handheld devices provide a way to interact with the virtual environment. Users can control it by clicking, sliding, dragging, etc.

[0073] Force feedback and vibration feedback: Handheld devices can simulate the texture of virtual objects through vibration or motors, enhancing the user's sense of immersion.

[0074] Trainees interact with the virtual reality scene through handheld operating devices, and the virtual scene responds to the trainees' instructions in real time. For example, in the training scenario, the trainees perform the gastric tube insertion operation through the handheld operating device, and the virtual scene will give corresponding feedback based on the trainees' actions:

[0075] Virtual patient reactions: The virtual patient may react differently to the trainee's actions, such as changes in limbs or even changes in physiological conditions (for example, the appearance of a virtual heartbeat);

[0076] Somatosensory feedback: When students are operating, the handheld device simulates touch through vibration, force feedback and other technologies, allowing students to sense the physical state of the virtual patient's body, such as the depth and force of gastric tube insertion.

[0077] Error correction and guidance: The system in the virtual scene may provide real-time error feedback to help students correct their mistakes; for example, if the virtual patient feels uncomfortable, the system will prompt the student to adjust the operation method or strength.

[0078] Furthermore, the VR all-in-one machine and the handheld operating device are also provided with a motion tracking system, which is used to track the trainee's head and hand movements in real time. The motion tracking system includes several sensor modules, which synchronize the trainee's movements to the virtual reality environment in real time by sensing the position, direction and movement speed of the trainee's head and hands, thereby reflecting the interaction process between the trainee and the virtual patient.

[0079] The motion tracking system is mainly used to simulate the trainees' head observation behavior and hand operation behavior during the gastric tube insertion process to ensure that the interactive effect of the virtual reality environment is authentic;

[0080] Head Tracking:

[0081] Perspective synchronization: Track the student's head direction to make the field of view changes in the VR environment consistent with the actual head movement;

[0082] Observation angle adjustment: Trainees can adjust the observation angle through natural head movements, such as lowering their heads to check the insertion of the gastric tube, and turning their heads left and right to observe the physiological reactions of the virtual patient.

[0083] Posture monitoring: Analyze students’ observation habits to determine whether they have made incorrect observations (such as ignoring key operation steps);

[0084] Hand Tracking:

[0085] Simulate the action of gastric tube insertion: track the movement trajectory, strength and angle of the trainee's hand to determine whether the intubation process is standardized; for example, the system can detect: whether the gastric tube is inserted too fast or too slow; whether the insertion angle is correct to avoid accidental insertion into the trachea; whether the operation force is reasonable to prevent damage to the patient's throat;

[0086] Real-time error feedback: When the system detects that the trainee’s intubation angle is wrong or the force is inappropriate, it will provide real-time feedback, such as: using color or arrows to indicate the correct insertion direction in the VR environment; using tactile feedback (handle vibration) to remind the trainee to adjust the operation.

[0087] The motion tracking system mainly includes the following core components:

[0088] Sensor Module:

[0089] Inertial sensors, which consist of accelerometers, gyroscopes, and magnetometers, are responsible for measuring angular velocity, acceleration, and direction changes. They can be used to detect information such as the rotation of the trainee's head, the tilt angle of the hand, and the trajectory of movement;

[0090] Optical tracking sensors use infrared cameras or laser sensors installed on all-in-one VR headsets and handheld operating devices to perform external optical positioning.

[0091] Ultrasonic / radio frequency (RF) tracking module, which determines the spatial position of hands and head through ultrasonic or RF signals, is particularly suitable for tracking compensation in occluded environments.

[0092] It should be noted that the collaboration between all-in-one VR devices, handheld devices and motion tracking systems depends on efficient data transmission protocols. The current mainstream solution is Wi-Fi 6E: it supports high-frequency bands (6GHz) and multi-channel parallel transmission, which can meet the low-latency requirements of high-resolution motion tracking data (such as full-body motion capture).

[0093] In addition, to ensure the consistency of vision and movement, the motion tracking system needs to update data at a frequency of at least 90Hz. For example, the optical tracking camera matches the VR rendering frame rate through high-speed image sampling (such as 120fps) to avoid screen tearing. Through the above mechanism, the VR system can strike a balance between latency, accuracy and cost to support a natural interactive experience.

[0094] Furthermore, the virtual patient intelligent state system includes:

[0095] The virtual patient generation module is used to generate virtual patients and collect the body position changes of virtual patients in real time. The data of body position changes are collected into the system through the data transmission module to provide dynamic physiological status for the virtual patient model;

[0096] The core task of this module is to produce virtual patients and continuously collect data on the body position changes of virtual patients. By accurately simulating the body position changes of virtual patients, the system can create a real clinical environment and allow trainees to train in a variety of body positions. These body position changes may include lying, sitting, standing, etc. These changes will affect the physiological state of the virtual patients. For example, changing body position may affect the activity of the stomach, etc. The virtual patient generation module not only "creates" virtual patients, it must also track and record body position change data in real time, and transmit these data to the system in real time through the data transmission module to ensure dynamic updating of the physiological state.

[0097] Physiological state change simulation module, which dynamically simulates the virtual patient's gastric movement, reflux and discomfort reaction according to the virtual patient's physiological data;

[0098] In the dynamic simulation of the physiological state of virtual patients, this module assumes the core responsibility and uses sensor data to simulate the reactions of organs such as the stomach. For example, during gastric tube insertion training, the virtual patient may show physiological reactions such as reflux, gastric movement, and gastric wall contraction. These reactions are highly consistent with the physiological mechanisms of actual patients. By simulating these physiological changes, trainees can learn how to cope with different physiological states and adjust operations to reduce harm or discomfort to patients. In addition, the module can also provide real-time feedback on changes in physiological data based on the trainees' operations, helping trainees to understand and adjust treatment plans in a timely manner.

[0099] The virtual patient feedback module generates virtual feedback based on the changes in the virtual patient's physiological state, simulating the stomach reaction, muscle contraction and discomfort during the insertion of the gastric tube. The virtual feedback is fed back to the trainees through graphics, audio and visual prompts, helping the trainees to perceive the virtual patient's physiological reactions in real time and ensure that the trainees can adjust their operations according to the feedback of the virtual patient;

[0100] The goal of this module is to generate virtual feedback based on changes in the virtual patient's physiological state. By integrating graphics, audio, and visual cues, the system can simulate the patient's gastric reactions, muscle contractions, and other discomfort during gastric tube insertion. Virtual feedback is delivered to trainees through audio cues (such as the patient's groans or uncomfortable sounds), graphic displays (such as the virtual patient's facial expressions or changes in body position), and visual feedback (such as changing physiological data charts or status indicator lights). These feedbacks can help trainees accurately perceive the patient's physiological reactions, thereby adjusting their operating skills based on the feedback and avoiding mistakes or inappropriate behavior in operation.

[0101] It should be noted that the virtual patient intelligent state system is not only used for training, but also for assessing trainees' abilities. By recording trainees' various behaviors during the operation and the reactions of virtual patients, the system can assess trainees' clinical skill levels. For example, the system can analyze whether trainees can take timely and appropriate actions when virtual patients have uncomfortable reactions, whether they can accurately adjust the insertion method of the gastric tube, and even judge whether trainees have sufficient ability to handle complex clinical situations through changes in the physiological state of virtual patients.

[0102] In addition, according to the different levels and needs of trainees, the virtual patient intelligent state system also has certain adaptability and personalized training capabilities. For example, for beginners, the system may reduce the frequency of virtual patients' uncomfortable reactions and provide more feedback to help trainees improve their skills; for trainees with certain experience, the system can simulate more complex clinical scenarios, increase the difficulty of patients' reactions, and provide more challenging training tasks. This personalized training mode can ensure that trainees can maximize their respective skill levels.

[0103] Furthermore, the virtual patient generation module simulates the changes in the virtual patient's body position through a virtual skeleton and joint motion model, and captures the position and posture of the virtual patient in three-dimensional space in real time.

[0104] Among them, the virtual patient generation module is the core part of the virtual medical simulation system. It is mainly responsible for creating realistic virtual patient images and tracking their body position changes and movements in real time. This module uses virtual skeleton and joint motion model technology to achieve accurate simulation of the virtual patient's position, posture and movement in three-dimensional space.

[0105] In detail, the virtual skeleton is the basis of the virtual patient's movement ability. It is composed of a series of joints and bone connections, similar to the human skeletal system. Each joint has independent coordinate information and can be adjusted according to the movement parameters, thereby realizing flexible movement of various parts of the human body, such as:

[0106] Key parts such as the head, neck, torso, and limbs are controlled by multiple virtual joints;

[0107] The range of motion of the joints is limited by the physiological structure of the human body to ensure the authenticity of the movements (e.g. the knee joint can only bend within a certain range);

[0108] The joints are connected by "virtual muscles" and "physical constraints" to ensure smooth movement.

[0109] The joint motion model is used to simulate the natural movements and posture changes of virtual patients, mainly including:

[0110] Rigid body dynamics model: ensures that the movement of limbs and torso conforms to real physical laws;

[0111] Inverse kinematics: Calculate the optimal joint angles based on the target position, so that the virtual patient can perform ergonomic movements (such as sitting up and turning over);

[0112] Muscle drive system: simulates muscle contraction and relaxation, affecting movement range and speed.

[0113] In addition, the virtual patient generation module can dynamically track the patient's position and posture in the 3D environment, mainly through the following technologies:

[0114] Motion capture, combining optical sensors (such as depth cameras, infrared tracking systems) or inertial sensors (IMU) to capture the real movement trajectory of the human body and map it to the virtual patient to make its movements more natural;

[0115] Position tracking, using coordinate transformation technology to align the position information of the virtual patient with the environmental coordinate system, ensuring that its movement in the 3D scene is consistent with the real space;

[0116] Posture recognition, through deep learning algorithms, analyzes joint data and automatically identifies the current posture of the virtual patient, such as: lying flat, prone, side-lying, sitting, and standing.

[0117] The virtual patient generation module can not only capture changes in body position, but also actively drive body position adjustments in medical simulation scenarios, such as:

[0118] Passive position change (driven by external force) trains trainees on how to adjust the patient's position in medical scenarios, such as turning the patient over for nursing care, raising the patient's upper body, etc.

[0119] Active postural adjustments (patient-initiated movements), for example, the virtual patient can simulate adjusting posture due to discomfort or respond to painful stimuli.

[0120] Furthermore, the physiological state change simulation module includes a biomechanical model and a physical engine, which ensures the realistic representation of the virtual patient's physiological state by simulating physiological phenomena such as gastric wall contraction, expansion and gastric content reflux;

[0121] The biomechanical model includes simulating the elastic coefficient of the stomach wall using the Mooney-Rivlin model, simulating the damping coefficient using the Voigt model, and simulating the contraction frequency using a periodic external force function. According to the nonlinear characteristics of human soft tissue, the stomach wall is usually modeled as a hyperelastic material;

[0122] The stress-strain energy function of the Mooney-Rivlin model is:

[0123] W = C1 (I1-3) + C2 (I2-3);

[0124] Among them, C1, C2 are material constants, I1, I2 are main invariants, reflecting the strain state, the elasticity of the stomach wall depends on the individual's health status, age, etc., C1, C2 can be given in combination with theoretical data;

[0125] The stomach wall is not only hyperelastic, but also has obvious viscoelastic behavior, that is, the tissue not only stores elastic energy, but also dissipates energy due to the flow of internal fluid (such as interstitial fluid). The viscoelastic properties of the stomach wall need to be introduced into the Voigt model, and the mechanical equation is in the form of:

[0126]

[0127] Where k is the elastic modulus, It is the derivative of displacement with respect to time. The damping coefficient is usually taken as c = 0.1 N·s / m to simulate the energy dissipation of fluid flow in tissues.

[0128] Contraction frequency: The frequency of gastric peristaltic waves is about 3 times / minute, which can be simulated by a periodic external force function (such as F(t) = A·sin(2πft)), where f = 0.05 Hz;

[0129] Based on the above, the entire gastric dynamics is described by the viscoelastic differential equation:

[0130]

[0131] Among them, M is the mass matrix, K and C are the stiffness matrix and damping matrix respectively, and F ext is the external force (such as peristaltic contraction force), therefore, F ext (t) can be expressed as an external time-dependent creep force. The numerical solution method can use the implicit Newton iteration method, which improves convergence by linearizing the stiffness matrix and is suitable for high-precision offline simulation.

[0132] The physics engine uses Unity or Unreal engine, in which physical materials can be customized to simulate the friction, rebound and other characteristics of the stomach wall, and to render the deformation, peristalsis, vibration and reflux process of the stomach wall in real time. Its working principle will not be elaborated here.

[0133] Furthermore, the augmented virtual reality feedback system includes a visual alternative to tactile feedback module, a virtual resistance display module, and a sound feedback module, which are used to improve the trainees' operation accuracy and immersion.

[0134] The visual substitution tactile feedback module simulates tactile feedback through visual elements in virtual reality. The visual substitution tactile feedback module provides visual instructions by rendering the physiological reactions of virtual patients (such as stomach expansion and contraction, etc.), helping trainees perceive the effect of the operation and ensuring that trainees can accurately judge the situation of gastric tube insertion through visual feedback;

[0135] The implementation of the visual alternative tactile feedback module includes:

[0136] Virtual physiological reaction rendering: Through high-precision modeling and dynamic rendering technology, the physiological changes of patients during intubation are simulated, such as the expansion, contraction, and bloating of the stomach. These visual signals are synchronized with the operation in real time to help trainees understand the physiological impact of the current operation;

[0137] Visual highlighting prompts: At key points, such as when the insertion is too deep or the angle is deviated, the system can simulate tactile warnings through color changes, light effect prompts, etc. to indicate abnormal operation;

[0138] Immersive feedback: Through stereoscopic vision and real-time response mechanism, students can have the visual illusion of "contact" and "pressure" being restored, thus improving learning effects.

[0139] The virtual resistance display module simulates the visual "resistance" or "collision" effect during operation through a handheld device. The virtual resistance display module simulates the resistance change during the gastric tube insertion process by changing the performance of the virtual patient's stomach state, allowing trainees to perceive the change in difficulty of the operation through visual feedback;

[0140] The virtual resistance display module uses the following mechanism:

[0141] Dynamic scene resistance simulation: The system dynamically adjusts the response of the stomach model according to the depth, angle and speed of the operation. For example, when the cannula enters the stomach, the model shows that the stomach wall produces "visual depression" or "elastic deformation";

[0142] Operation path feedback: through visual deformation, intubation path color change and other means, it indicates whether the current path is smooth, whether it encounters "virtual resistance" or potential risk areas (such as mistaken entry into the trachea);

[0143] In conjunction with handheld devices: Although it is mainly visual feedback, when used in conjunction with a handheld device with basic vibration or force simulation functions, it can further enhance the "visual-motion" feedback coupling and improve the reproduction of the operating feel.

[0144] The sound feedback module provides audio prompts, such as the "gurgling" sound of the stomach and the groaning sound of the patient. The sound feedback is synchronized with the physiological response of the virtual patient, helping the trainees to judge the accuracy of the operation and improve the trainees' sensitivity to the response of the virtual patient;

[0145] The sound feedback module includes:

[0146] Physiological sound simulation: such as the "gurgling" sound of gastric fluid peristalsis and the sound of gas movement, etc., are played synchronously with the specific stage of gastric tube insertion through real-time synthesis technology to enhance the "sense of presence";

[0147] Patient subjective reaction sound effects: such as the uncomfortable groaning and vomiting reaction caused by intubation too deep, which can help trainees judge whether the current operation causes discomfort to the patient, so as to adjust the operation behavior in time;

[0148] Sound and action synchronization mechanism: The system has a built-in event trigger mechanism that binds the students' specific actions with sound feedback to achieve "sound and action consistency" and enhance perceptual coupling.

[0149] Further, the machine learning adaptive nonlinear response system includes:

[0150] Trainee operation data collection module collects trainee operation data in real time;

[0151] Adaptive algorithm analysis module, which analyzes operation data through machine learning algorithms and determines the characteristics of students' operations;

[0152] Virtual patient physiological response adjustment module, which adjusts the physiological response of the virtual patient according to the trainee's operation characteristics;

[0153] The adaptive algorithm analysis module uses a machine learning algorithm to analyze the student's operation characteristics and is expressed by the following formula:

[0154]

[0155] Among them, F(t) represents the strength of the trainee's operation, θ(t) represents the trainee's operation angle, v(t) represents the trainee's operation speed, d(t) represents the directionality of the trainee's operation, α1, α2, α3, and α4 are weight coefficients, which are adjusted according to the trainee's operation data, and β1, β2, β3, and β4 are nonlinear exponents, which represent the nonlinear relationship between each operation parameter and the virtual patient's response.

[0156] Further, the closed-loop feedback system comprises:

[0157] The data comparison and feedback calculation module compares the trainee's operation data with the virtual patient's physiological response in real time, calculates feedback data, and provides real-time feedback based on the trainee's operation behavior, including the intensity of the physiological response and the nature of the feedback;

[0158] This module not only compares data, but also uses algorithms to calculate whether the trainee's operation effect meets the predetermined goals. For example, if the trainee's operation is improper (such as the wrong intubation angle or too fast speed), the system can analyze and calculate the intensity of the virtual patient's physiological reaction, such as severe stomach distension or increased vomiting reaction;

[0159] The system generates feedback data based on the trainee's operation behavior and the physiological response of the virtual patient. The feedback includes two aspects:

[0160] Feedback intensity: such as the magnitude of changes in physiological responses. The stronger the feedback, the further the trainee’s operation deviates from the target.

[0161] Nature of feedback: Feedback can be divided into positive (encouraging students to continue the operation) and negative (reminding students to make corrections). Negative feedback is usually accompanied by abnormal physiological reactions, such as excessive stomach distension, painful groans from virtual patients, etc., which warn students of improper operation.

[0162] The real-time adjustment module dynamically adjusts the virtual patient's physiological state and operation feedback according to the comparison results. The adjustment includes changing the virtual patient's gastric reaction, vomiting intensity, etc., so that the trainees can adjust the operation in time according to the virtual patient's reaction;

[0163] When the trainee is operating, the virtual patient's physiological state (such as stomach reaction, breathing changes, heartbeat, etc.) will be adjusted in real time according to the trainee's operation behavior. For example, if the trainee inserts the gastric tube too deep, the virtual patient's stomach may become over-inflated or uncomfortable. The system will give feedback to the trainee through these physiological reactions, allowing him to perceive the consequences of incorrect operation;

[0164] Or adjust the feedback content and form in real time according to the changes in the virtual patient's physiological state. For example, the virtual patient may show vomiting or shortness of breath. These changes prompt the trainee to immediately adjust the operation, such as reducing the insertion speed, adjusting the insertion depth, etc.

[0165] When the trainee's operation deviates from the predetermined standard, the system can warn the trainee through sound and light prompts or physiological reactions (such as the patient's groaning becomes more severe). At the same time, the system can also provide adjustment suggestions through visual, sound or virtual handle feedback to help trainees adjust their operating strategies.

[0166] The training difficulty adjustment module automatically adjusts the training content and the level of detail of feedback according to the trainees' performance to provide a personalized training experience. For example, for novice trainees, the system can reduce the intensity of the virtual patient's physiological reactions and reduce the complexity of operations. For experienced trainees, the system can increase the intensity of the virtual patient's reactions and simulate more complex clinical situations to challenge the trainees' skills.

[0167] Working process:

[0168] Equipment preparation and startup:

[0169] The trainee wears the VR all-in-one device and prepares for gastric tube insertion training through the handheld operating device. The VR all-in-one device and the handheld operating device are connected through the VR computer, and the system starts and loads the virtual reality environment;

[0170] Virtual patient creation and initialization:

[0171] Virtual patients are created through the virtual patient generation module, and the three-dimensional view and physiological status (such as gastric movement, reflux, etc.) are rendered and displayed in real time, simulating the physiological reactions of virtual patients such as body position changes and gastric discomfort;

[0172] Student interaction and operation:

[0173] Trainees interact with virtual patients through handheld devices to simulate the operation of gastric tube insertion. The sensing module of the handheld device monitors the trainees' operation force, angle, speed and other data in real time and transmits them to the virtual reality environment. The system adjusts the virtual patient's response according to the trainees' operation, including gastric reaction, muscle contraction and discomfort.

[0174] Virtual patient physiological feedback:

[0175] Based on the trainees' operations, the virtual patient intelligent state system simulates gastric movements, gastric reflux and other reactions according to physiological data. The system combines the trainees' operation information (such as strength, angle, etc.) with the feedback data of the virtual patient to provide realistic reactions and feedback;

[0176] Augmented Virtual Reality Feedback System:

[0177] The visual substitute tactile feedback module, virtual resistance display module, and sound feedback module work together to improve trainees' operation accuracy and immersion through multi-sensory feedback. When trainees insert a gastric tube, the resistance of the handle, the feedback of the virtual patient, and the sound prompts all help them better understand the operation effect;

[0178] Machine Learning Adaptive Systems:

[0179] The system collects the trainee's operation data in real time and analyzes the trainee's operation characteristics (force, angle, speed, etc.) through an adaptive algorithm. Based on the analysis results, the virtual patient's physiological response is adjusted to simulate the real situation, such as the elasticity, resistance, and gastric movement of the stomach wall.

[0180] Closed-loop feedback and training optimization:

[0181] The closed-loop feedback system compares the trainee's operation data with the physiological response of the virtual patient and adjusts the feedback content of the virtual patient in real time. The system dynamically adjusts the training content and feedback through data calculation to ensure that the training difficulty matches the trainee's level and provide a personalized learning experience.

[0182] End of training and evaluation:

[0183] After the trainees complete a round of operations, the system provides real-time evaluation, points out errors and deficiencies in the operations, and automatically adjusts the content and feedback of subsequent training based on the trainees' performance to promote skill improvement.

[0184] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A virtual reality-based teaching simulation device for intermittent gastric tube insertion, characterized in that: include: VR all-in-one devices, handheld operating devices and VR computers; The VR all-in-one machine realizes real-time visual simulation of a virtual patient by displaying a three-dimensional view and real-time physiological status of the virtual patient, wherein the three-dimensional view of the virtual patient includes dynamic changes of various parts of the virtual patient; The handheld operating device is used to simulate the gastric tube insertion operation. The trainee interacts with the virtual patient through the handheld operating device. The handheld operating device includes an operating handle and a sensing module. The sensing module detects the trainee's operating force, angle and speed in real time, and transmits these operating data to the virtual reality environment for synchronizing the virtual patient's response. The VR computer includes a virtual patient intelligent state system, an augmented virtual reality feedback system, a machine learning adaptive nonlinear response system, and a closed-loop feedback system; The virtual patient intelligent state system generates feedback of the virtual patient based on the simulated data, so as to simulate the changes of the physiological state of the virtual patient; The visual substitution tactile feedback module, virtual resistance display module and sound feedback module of the augmented virtual reality feedback system improve the trainees' operation accuracy and immersion; The machine learning adaptive nonlinear response system adjusts the physiological response of the virtual patient according to the trainee's operation behavior; The closed-loop feedback system adjusts the physiological response and feedback content of the virtual patient in real time based on the trainee's operation data and the physiological response of the virtual patient.

2. A virtual reality-based gastric tube intermittent insertion teaching simulation device according to claim 1, characterized in that: The VR all-in-one machine is a virtual reality head-mounted display with an independent processor, and a basic environment for virtual reality operation of the VR all-in-one machine is constructed by installing a VR operating system; The VR all-in-one machine provides software drivers for the handheld operating device by installing a VR interactive SDK. The trainees send sensing or control instructions to the virtual reality scene through the handheld operating device, and the virtual scene feeds back the somatosensory experience and acts on the trainees through the handheld operating device.

3. The virtual reality-based teaching simulation device for intermittent gastric tube insertion according to claim 2, characterized in that: The VR all-in-one machine and the handheld operating device are also provided with a motion tracking system, which is used to track the trainee's head and hand movements in real time. The motion tracking system includes several sensor modules, which synchronize the trainee's movements to the virtual reality environment in real time by sensing the position, direction and movement speed of the trainee's head and hands, thereby reflecting the interaction process between the trainee and the virtual patient.

4. The virtual reality-based teaching simulation device for intermittent gastric tube insertion according to claim 1, characterized in that: The virtual patient intelligent state system comprises: A virtual patient generation module is used to generate virtual patients and collect the body position changes of virtual patients in real time; Physiological state change simulation module, which dynamically simulates the virtual patient's gastric movement, reflux and discomfort reaction according to the virtual patient's physiological data; The virtual patient feedback module generates virtual feedback according to the changes in the virtual patient's physiological state, simulating the gastric reaction, muscle contraction and discomfort during the insertion of the gastric tube.

5. The virtual reality-based teaching simulation device for intermittent gastric tube insertion according to claim 1, characterized in that: The virtual patient generation module simulates the changes in the virtual patient's body position through a virtual skeleton and joint motion model, and captures the position and posture of the virtual patient in three-dimensional space in real time.

6. The virtual reality-based teaching simulation device for intermittent gastric tube insertion according to claim 1, characterized in that: The physiological state change simulation module includes a biomechanical model and a physical engine; The biomechanical model includes simulating the elastic coefficient of the stomach wall using the Mooney-Rivlin model, simulating the damping coefficient using the Voigt model, and simulating the contraction frequency using a periodic external force function; The physics engine uses Unity or Unreal engine.

7. The virtual reality-based teaching simulation device for intermittent gastric tube insertion according to claim 1, characterized in that: The augmented virtual reality feedback system includes a visual alternative to tactile feedback module, a virtual resistance display module, and a sound feedback module, which are used to improve students' operating accuracy and immersion.

8. The virtual reality-based teaching simulation device for intermittent gastric tube insertion according to claim 3, characterized in that: The machine learning adaptive nonlinear response system comprises: Trainee operation data collection module collects trainee operation data in real time; Adaptive algorithm analysis module, which analyzes operation data through machine learning algorithms and determines the characteristics of students' operations; The virtual patient physiological response adjustment module adjusts the virtual patient's physiological response according to the trainee's operating characteristics.

9. The virtual reality-based teaching simulation device for intermittent gastric tube insertion according to claim 8, characterized in that: The adaptive algorithm analysis module uses a machine learning algorithm to analyze the student's operation characteristics and is expressed by the following formula: Among them, F(t) represents the strength of the trainee's operation, θ(t) represents the trainee's operation angle, v(t) represents the trainee's operation speed, d(t) represents the directionality of the trainee's operation, α1, α2, α3, and α4 are weight coefficients, which are adjusted according to the trainee's operation data, and β1, β2, β3, and β4 are nonlinear exponents, which represent the nonlinear relationship between each operation parameter and the virtual patient's response.

10. The virtual reality-based teaching simulation device for intermittent gastric tube insertion according to claim 9, characterized in that: The closed-loop feedback system comprises: Data comparison and feedback calculation module, which compares the trainee's operation data with the physiological response of the virtual patient in real time and calculates feedback data; A real-time adjustment module dynamically adjusts the virtual patient's physiological state and operation feedback according to the comparison results; The training difficulty adjustment module automatically adjusts the training content and feedback details according to the students' performance to provide a personalized training experience.

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