A head-mounted intelligent projection navigation system for assisting ear acupoint pressing bean and other traditional Chinese medicine treatment acupoint positioning

Abstract

The application discloses a kind of head-mounted intelligent projection navigation systems for assisting ear acupoint pressing bean etc. Chinese medicine therapy acupoint positioning, the system includes head-mounted support, projection host and intelligent probe pen, generate auricle three-dimensional point cloud by structured light scanning and adopt non-rigid registration algorithm to fit standard acupoint model to individual surface, realize the individualized accurate positioning of projection error less than 2mm;Real-time probe tip position is detected by visual tracking algorithm and with projected light point dynamic following, when detecting that resistance reduces more than 30%, automatically highlight display sensitive point with red flashing light point;Six-axis IMU is integrated to realize head shaking automatic compensation, and projection alignment is recovered within 0.3 seconds;The application solves the problems of poor positioning accuracy, lack of visual feedback, easy displacement and inability to reuse treatment records in the prior art, greatly improves the accuracy and operation efficiency of ear acupoint positioning.

Description

Technical Field

[0001] This invention relates to the field of traditional Chinese medicine medical device technology, and in particular to a head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure. Background Technology

[0002] In traditional Chinese medicine clinical practice, several projection-based auxiliary devices have been developed to assist practitioners in quickly and accurately locating acupoints on patients. For example, Chinese Patent Publication No. CN213884206U discloses a head-mounted auricular acupoint projection device. This device uses a headband to fix the projector in front of the practitioner's forehead, projecting pre-stored standard auricular acupoint charts directly onto the patient's auricle. Such devices aim to address the inefficiency caused by the need for practitioners to repeatedly consult paper charts and frequently shift their gaze in traditional therapies, thus providing preliminary visualization guidance for auricular acupoint location.

[0003] However, existing projection-based positioning devices still have problems in actual clinical operation. First, these devices typically use fixed, uniform two-dimensional acupoint maps for projection, completely ignoring the significant differences in the three-dimensional morphology of the auricle between individuals. Directly projecting a planar map onto the auricle, which has a complex curved surface, will produce non-linear image distortion and positional deviation, causing the center of the acupoint indicated by the projection to not accurately coincide with the actual anatomical location, thus directly affecting the therapeutic effect of auricular acupressure and other therapies. Second, existing devices lack integration with the ability to perceive the physiological state of acupoints. Academic research shows that when there is a functional imbalance in the corresponding organs of the human body, the electrical properties (such as resistance) of the relevant acupoints will be significantly reduced, forming "sensitive points," and these dynamically changing sensitive points are often the optimal stimulation targets for therapeutic effects. However, existing technology cannot detect or provide feedback on these individualized sensitive point information, and operators still need to rely on their own experience for secondary judgment, failing to achieve truly precise positioning. Third, during long-term, multi-step clinical procedures, the operator's head inevitably shakes due to handling consumables, adjusting posture, etc. When repositioning, due to the lack of a perception and compensation mechanism for head displacement, the projected image will shift and cannot be automatically restored to alignment. The operator has to interrupt the treatment process to manually refocus and calibrate, which seriously affects the continuity and efficiency of clinical procedures.

[0004] Therefore, in response to the problems mentioned above, this invention proposes a head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure. Summary of the Invention

[0005] To overcome the problems of poor individual adaptability, inability to sense and respond to sensitive points, and projection deviation caused by head shaking in existing technologies, this invention proposes a head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure. This system achieves personalized and accurate projection by integrating three-dimensional scanning and surface fitting technologies, uses an intelligent probe pen with visual tracking function to realize real-time detection and dynamic visualization feedback of sensitive points, and introduces a posture sensing module to automatically compensate for projection deviations caused by head displacement. Thus, it provides an intelligent acupoint navigation system with more accurate positioning, more consistent operation, and learning capabilities.

[0006] The technical solution of this invention is: a head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure, comprising: Headband-style support for wearing on the operator's head; The projector, mounted on a head-mounted stand, includes an optical projection module and a visual tracking module; The intelligent probe pen communicates wirelessly with the projector host. The probe base of the probe pen is equipped with an infrared tracking ring. The probe pen has a built-in resistance detection circuit to detect the resistance value of the skin that the probe tip contacts in real time. The mobile terminal APP communicates wirelessly with the projection host. The mobile terminal APP is used to create and store patient files. The patient files include at least the three-dimensional point cloud data generated during the first treatment, the acupoint projection coordinate map, and the three-dimensional coordinates of the detected sensitive points. The visual tracking module includes an RGB camera, which captures images containing the infrared tracking ring in real time at a frame rate of no less than 30 frames per second, and calculates the real-time position coordinates of the probe tip of the probe pen in three-dimensional space through a visual positioning algorithm. The projection host is used to achieve real-time dynamic tracking of the projected light spot and visualization feedback of sensitive points through the following steps: S1, place the probe tip of the probe pen on a known projection reference point, press the confirmation button on the probe pen, and the system records the three-dimensional spatial coordinates of that point as the reference origin; S2, the visual positioning algorithm determines the direction vector by combining the position change of the infrared tracking ring in the continuous frame image with the geometric parameters of the probe pen (where the distance from the tracking ring to the probe tip is 5mm) through ellipse fitting (real-time calculation of the displacement vector of the probe tip relative to the reference origin). S3, based on the displacement vector, updates the current spatial coordinates of the probe tip in real time, and drives the optical projection module to project the projection light point to the corresponding new position at an update frequency of no less than 30 times per second, so as to realize the real-time and dynamic following display of the projection light point on the target position of the acupoint on the patient's body surface observed by the operator; S4, the resistance detection circuit applies a constant microcurrent of 10μA to the probe, with a sampling frequency of 100Hz. The resistance value of the patient's normal skin area is used as a reference. When the current skin resistance value is detected to be more than 30% lower than the reference resistance value, it is determined that a sensitive point has been detected. At this time, the projector switches the color of the projected light spot at that location to red and flashes brightly at a frequency of 3Hz. At the same time, the flat linear vibration motor built into the probe pen generates vibration feedback for 0.3 seconds.

[0007] The projection host also includes a 3D scanning module, which includes an infrared structured light emitter with a wavelength of 940nm and an infrared camera with a resolution of 1280×720 and a frame rate of 60fps. The projection host is used to perform the following adaptive modeling and learning reuse process, taking auricular acupuncture as an example: During the first treatment: The structured light emitter projects an infrared dot array of approximately 30,000 points onto the patient's auricle. An infrared camera captures the structured light deformation image, and a three-dimensional point cloud data of the auricle containing 5,000-10,000 points is generated using the triangulation principle. Retrieve from memory a standard three-dimensional model of ear acupoints, which is based on the GB / T 13734-2008 standard and contains the spatial coordinates of 93 standard acupoints; The Iterative Closest Point (ICP) non-rigid registration algorithm is used to fit the standard model with the three-dimensional point cloud data of the auricle. The convergence condition is set to the error between two iterations being less than 0.1 mm. The actual projection coordinates of each acupoint on the individual auricle are calculated to achieve accurate positioning with a projection error of less than 2 mm. During follow-up treatment: By retrieving the patient's file via voice command, the system performs point cloud registration between the historical 3D point cloud data and the current patient's auricle, automatically restoring the acupoint projection position and sensitive point position from the last treatment, and displaying the historical sensitive point area in the projection screen in the form of a red halo, without the need for re-detection.

[0008] Preferably, the head-mounted support or projection host also integrates an attitude sensing module, which includes a six-axis inertial measurement unit (IMU) with an acceleration range of ±8g, an angular velocity range of ±1000° / s, and a sampling frequency of 200Hz. This attitude sensing module is used to perform the following automatic head sway compensation process: (1) When the system starts, the current IMU attitude is recorded as the reference attitude and stored in the form of a quaternion; (2) The acceleration and angular velocity data are fused by Kalman filtering, and the current attitude quaternion is output; (3) When the angular velocity exceeds 50° / s or the acceleration exceeds 0.5g, it is determined that the head has started to move. The acceleration is double integrated, and the displacement trajectory (Δx, Δy, Δz) and angle change (Δθ) of the head in space are calculated in real time. (4) When the head movement stops and the Euler angle difference between the new posture and the reference posture is less than 5°, it is determined to be a reset; (5) Based on the recorded displacement trajectory and angle change, calculate the rotation matrix R_comp and displacement vector T_comp that the projection optical engine needs to compensate, drive the projection optical engine to adjust the projection direction, restore the projection alignment within 0.3 seconds, and at the same time trigger the infrared ranging sensor to automatically focus.

[0009] Preferably, the projector is mounted on a head-mounted bracket via a quick-release buckle, which includes a metal female base and a locking mechanism, and is equipped with a release button; the system has a treatment mode and a teaching mode. For the treatment mode, the projector is mounted on the headgear, and the optical projection module projects green or red indicator lights with a brightness of 50-300 lumens and a resolution of 854×480. The diameter of the light spot is 3-5mm, which is used for clinical operation guidance. For the teaching mode, press the release button to remove the projector from the head-mounted stand and place it flat on the table with the anti-slip silicone pad on the bottom in contact with the table. Switch to teaching mode via voice command, and the optical projection module will automatically switch the projection screen to display a standard auricle atlas. The acupoint locations are highlighted and accompanied by text information, including the acupoint name, the meridian to which it belongs, and its main functions. The system supports acupoint-by-acupoint explanation, sequential playback, and assessment testing. The assessment testing function involves the system randomly generating questions, the student verbally stating the acupoint name, and the mobile terminal APP judging the correctness of the questions through voice recognition.

[0010] Preferably, the pen body and the probe of the smart probe are detachably connected, and the electrical contact connection is achieved through a gold-plated spring pin. The probe includes a probe base (made of PEEK (polyether ether ketone) high-temperature resistant plastic, 30mm in length and 8mm in diameter), a metal probe (made of 316L medical stainless steel, 1.5mm in diameter, with a tip radius R0.5mm), and an infrared tracking ring (made of 316L stainless steel ring, 10mm in outer diameter and 6mm in inner diameter, fixed to the base of the probe).

[0011] Preferably, the projector is provided with foldable magnifying lenses on the left and right sides. The magnifying lenses are optical resin aspherical lenses with a diameter of 25mm and a magnification of 2-3 times. The projector host integrates a Hall sensor to detect the unfolded state of the magnifying glass; When the magnifying glass is unfolded, the system automatically lights up two white LED patches for supplemental lighting. When the magnifying glass is folded, it is stored on the side of the projector, without taking up extra space.

[0012] Preferably, when in use, the system assists in the following traditional Chinese medicine therapies by aligning the head-mounted support and the projection host with the patient's body parts, including the head and face, chest and back, abdomen, or limbs: Acupuncture therapy: Projecting acupoint arrays to display acupuncture depth and angle guide lines, supporting continuous projection display of meridian pathways; Massage therapy: Project massage path planning lines, showing the area of ​​action of the techniques and the arrows indicating the direction of operation; Cupping therapy: The circular outline of the suction area of ​​the projection cups is available in three sizes: 3cm, 5cm, and 7cm. Multiple cups can be arranged at equal intervals. Different therapies correspond to different preset projection maps. After selecting the therapy type through the mobile terminal APP, the system automatically switches the projection map and sends control commands to the projection host via Bluetooth for execution.

[0013] The beneficial effects of this invention are: 1. This invention acquires three-dimensional point clouds of a patient's auricle through structured light scanning and uses a non-rigid registration algorithm to deform and fit the standard auricular acupoint model to the individual curved surface, so that the acupoint projection error is less than 2mm. This solves the problem of positioning deviation caused by ignoring the individual auricular shape differences in the existing technology and greatly improves the accuracy of individualized positioning.

[0014] 2. This invention integrates an intelligent probe pen with a resistance detection circuit and a visual tracking module, which dynamically displays the real-time position of the probe pen with projected light dots, and highlights a red flashing light dot when a sensitive point with a resistance reduction of more than 30% is detected, realizing a visual operation where detection is immediately visible, and solving the problem that existing probes only have sound prompts and lack intuitive position guidance.

[0015] 3. This invention integrates a six-axis inertial measurement unit within the headgear frame to monitor changes in head posture in real time. When head displacement is detected and the head is reset, the compensation matrix is ​​automatically calculated and the projection optical engine is driven to restore alignment within 0.3 seconds. This solves the problem of frequent manual calibration required due to projection offset caused by the operator's actions such as bending down to pick up objects, and ensures the continuity of the treatment process.

[0016] 4. This invention uses a quick-release buckle to allow the projector to be removed from the head-mounted stand and placed flat on the table. It can be switched to teaching mode with one click via voice command, automatically displaying text information such as acupoint names, meridians, and indications, and supports explanation and assessment tests for each acupoint. This allows for the use of a single device for both treatment and teaching modes, solving the problem of limited application scenarios in existing technologies.

[0017] 5. This invention establishes patient files through a mobile APP, storing 3D point cloud data, projection screenshots, and coordinates of sensitive points for each treatment. During follow-up visits, historical data is retrieved and the projection position is automatically registered and restored, solving the problem of time-consuming and inconsistent repositioning for each treatment of patients with chronic diseases. Attached Figure Description

[0018] Figure 1 The diagram shown is a schematic representation of the internal module structure of the projection host of the present invention. Figure 2 The diagram shown illustrates the principle of the surface fitting algorithm of this invention. Figure 3 The diagram shown is a schematic representation of the visual positioning algorithm of the present invention. Figure 4 The diagram shown is a schematic of the automatic head movement compensation algorithm of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] This invention provides an embodiment: This invention assists in the location and manipulation of acupoints in auricular acupressure, acupuncture, massage, or cupping therapy. The system includes a head-mounted support, a projector, and a smart probe pen. The head-mounted support is worn on the operator's head, providing a stable support platform for the entire system. The projector is mounted on the head-mounted support via quick-release clips and performs projection, scanning, tracking, and computational processing. The smart probe pen establishes wireless communication with the projector via Bluetooth Low Energy, detecting sensitive points on the auricle or other parts of the body surface and feeding the detection results back to the projector in real time, ultimately presenting them as visual light dots on the projected screen. The system also includes a mobile app, which communicates bidirectionally with the projector via Bluetooth and WiFi, enabling human-computer interaction functions such as voice control, patient file management, prescription retrieval, and switching between teaching modes.

[0021] During use, the operator wears the head-mounted bracket above the eyebrows, suspending the projector directly in front of the center of the forehead. After powering on, the system acquires three-dimensional point cloud data of the patient's auricle or body surface through structured light scanning, and uses a non-rigid registration algorithm to fit the standard acupoint model to the individual surface, generating personalized projection coordinates. Then, the operator picks up the intelligent probe pen, and the system captures the position of the probe pen tip in real time through the visual tracking module, dynamically following and displaying it as a projected light spot. When the probe pen detects a sensitive point where the resistance drops by more than 30%, the projected light spot changes color and flashing mode, and the probe pen generates vibration feedback. The operator can then directly perform treatment operations at the position indicated by the light spot.

[0022] During follow-up visits, the system can retrieve point cloud data from historical records, register it with the current patient's body surface, and automatically restore the location of the sensitive points from the previous visit, enabling precise repeat treatment.

[0023] In teaching mode, the projector can be removed from the head-mounted stand and placed flat on the table. The projected image automatically switches to a teaching chart with text labels such as acupoint name, meridian, and indications, supporting explanation and assessment tests for each acupoint.

[0024] In this embodiment, the head-mounted support will be described in detail: The headband uses an eyeglass frame structure, but it's not worn on the bridge of the nose; instead, it's positioned approximately 1 cm above the eyebrows. The headband consists of a main frame, left temple, right temple, forehead pad, suspension bracket, and quick-release buckle. The main frame is curved, approximately 150mm wide, and made of a resilient material to conform to the forehead contours of different users. Both the left and right temples are approximately 120mm long and adjustable, allowing them to hang above the user's ears. Together with the forehead pad, they form a three-point support, ensuring stability and comfort during extended wear. The forehead pad is made of medical-grade silicone, 5mm thick and 40mm wide. Positioned approximately 1 cm above the brow, it provides support and prevents slippage when the user tilts their head up or down.

[0025] The suspended bracket extends forward from the center of the frame, approximately 60mm in length, with a quick-release female connector at its end. This female connector is a composite structure of metal and plastic, featuring an internal locking mechanism and release button. When the male connector on the projector is inserted into the female connector, the locking mechanism automatically engages, emitting a "click" sound to indicate proper engagement; pressing the release button allows for easy removal of the projector. This design ensures the projector is stably suspended directly in front of the operator's brow, with the projection light path passing over the bridge of the nose and directing towards the ear on the same side or the front of the body, thus avoiding obstruction of vision.

[0026] Please see Figure 1In this embodiment, the projector host will be described in detail: The projector unit has a square box shape, with a side length of approximately 60mm and a thickness of approximately 35mm. The overall weight is controlled between 100-150g to reduce the burden on the operator's head. The unit integrates an optical projection module, a 3D scanning module, a visual tracking module, a posture sensing module, a control and communication module, a power supply module, a heat dissipation and sterilization module, and a magnifying glass assembly.

[0027] The optical projection module is a miniature projection engine employing digital light processing technology. Its luminous flux output is adjustable between 50-300 lumens, with a physical resolution of 854×480 pixels. This projection engine, in conjunction with a motorized zoom lens assembly, enables automatic focusing within a projection distance of 10-30cm, ensuring image clarity. The infrared range sensor, based on the time-of-flight principle, has a range of 5-50cm and a measurement accuracy of ±1mm. This sensor measures the distance from the projector to the target surface in real time and triggers the motorized zoom lens for automatic focusing, requiring no manual intervention.

[0028] The optical projection module employs a short-throw design, ensuring the projected image completely covers the entire auricle within a 10-15cm working distance. The auricle width is approximately 5-8cm, and the projected image slightly exceeds this range, guaranteeing clear projection even for peripheral acupoints. The lens optical axis is angled upwards at 5-10° to the horizontal plane, allowing the projected light to bypass the bridge of the nose and project directly onto the surface of the auricle on the same side, avoiding dark areas caused by nasal obstruction. In treatment mode, the optical projection module typically projects green or red indicator dots with a diameter of 3-5mm. This size allows for clear observation by the operator without covering too much skin, thus avoiding interference with the judgment of acupoint anatomical landmarks. When a sensitive point is detected, the dot switches to red and flashes at a frequency of 3Hz, providing a strong visual cue. In teaching mode, the projection module displays richer content, including a standard auricle atlas, highlighted acupoint locations, annotations of acupoint names, meridian affiliations, and indications. It can also overlay the outline of the auricle cartilage and a schematic diagram of vascular and nerve distribution.

[0029] Please see Figure 2 The 3D scanning module includes a structured light emitter, an infrared camera, and a main control chip equipped with a dedicated algorithm.

[0030] The structured light emitter uses a vertical-cavity surface-emitting laser (VCSEL) that emits infrared light at a wavelength of 940nm, which is invisible to the human eye and will not cause visual interference to the patient or operator. The emitter projects a dot matrix density of approximately 30,000 points arranged in a regular pseudo-random pattern. When projected onto the surface of the auricle, the dot matrix image will be distorted due to the undulations of the auricle's surface. The infrared camera has a resolution of 1280×720 pixels and a frame rate of 60 frames per second, enabling it to capture the distorted images of the structured light. Using the principle of triangulation, the system calculates the three-dimensional coordinates of each point on the auricle surface based on the known baseline distance between the structured light emitter and the infrared camera, and the offset of each light point in the image, ultimately generating a three-dimensional point cloud of the auricle containing approximately 5,000-10,000 points. The entire scanning process takes only about 2 seconds, requires no special cooperation from the patient, and is highly comfortable.

[0031] After obtaining individualized point cloud data, the system needs to deform and fit the standard auricular acupoint model onto this point cloud. The standard auricular acupoint 3D model is pre-stored in the system memory. This model is based on the "Auricular Acupoint Nomenclature and Location" (GB / T 13734-2008) and contains the precise spatial coordinates of 93 standard acupoints. The standard auricular acupoint 3D model is constructed on a representative human ear anatomy structure, and its shape is an averaged 3D curved surface. Due to significant differences in individual auricular morphology, directly using the standard model will lead to acupoint coordinate deviations; therefore, non-rigid registration is necessary.

[0032] The non-rigid registration algorithm uses the iterative nearest point algorithm, and its specific process includes: First, initialization is performed by translating the centroid of the standard model to the centroid of the patient's point cloud, roughly aligning the two models. Then, an iterative optimization loop is entered. For each point in the standard model, the point with the closest Euclidean distance in the patient's point cloud is searched to form a matching point pair. Based on these matching point pairs, a transformation matrix is ​​calculated, which includes rotation, translation, and deformation components (where the deformation component is implemented through thin-plate spline interpolation or affine transformation). This allows the standard model to undergo non-uniform stretching and bending to conform to the surface features of the individual auricle. The transformation matrix is ​​applied to all points of the standard model, updating their positions. Then, the root mean square error of the positional change of the standard model before and after this iteration is calculated. If the error is less than 0.1 mm, convergence is considered, and the iteration stops; otherwise, the next iteration continues.

[0033] After registration, each acupoint in the standard model has a new position in the patient's auricle coordinate space. The system stores the spatial coordinates of these acupoints in a projection mapping table and drives the optical projection module to project the acupoint markers to the corresponding positions. Clinical validation shows that after surface fitting, the average deviation between the projected acupoint positions and the anatomical positions manually located by experienced TCM doctors is 1.6 mm, with a maximum deviation of no more than 2.5 mm. In contrast, the average deviation of the unfitted fixed projection method reaches 4.8 mm, with a maximum deviation exceeding 8 mm. This result fully demonstrates the significant effect of surface fitting technology on improving positioning accuracy.

[0034] The smart probe pen consists of two parts: the pen body and the probe. The pen body is made of ABS plastic, approximately 120mm long and 15mm in diameter, and integrates a main control board, Bluetooth module, lithium battery, vibration motor, confirmation button, Type-C charging port, power switch, and LED indicator. The probe is detachable and includes a probe base made of PEEK material, a metal probe made of 316L medical-grade stainless steel, and an infrared tracking ring fixed to the base of the probe. The metal probe has a diameter of 1.5mm and a tip radius of 0.5mm to reduce pressure on the skin while ensuring stable electrical contact. The infrared tracking ring has an outer diameter of 10mm and an inner diameter of 6mm, also made of 316L stainless steel. Its surface optical reflectivity provides high contrast under infrared light, facilitating camera recognition. The probe and pen body are electrically connected via a gold-plated spring pin, ensuring reliable transmission of the resistance detection signal.

[0035] The probe pen's built-in resistance detection circuit applies a constant microcurrent of 10 microamps to the metal probe. This current value is far below the human perception threshold, ensuring absolute safety. The reference electrode is attached to the patient's arm or other neutral skin area. The probe pen continuously reads the voltage value between the probe and the reference electrode at a sampling rate of 100Hz and calculates the skin resistance according to Ohm's law. The system first collects the resistance value of a normal skin area of ​​the patient as a benchmark under operational guidance (measurement is performed on the earlobe or the back of the auricle, an area without acupoints). Subsequently, as the probe pen moves, the real-time resistance value is compared with the benchmark value. Based on extensive experimental statistics, the resistance of acupoints in pathological conditions is typically 30% to 50% lower than that of the surrounding normal skin. Therefore, this invention sets a threshold where the resistance decreases by more than 30% to determine a sensitive point. This threshold ensures sensitivity while avoiding false alarms caused by non-pathological factors such as skin humidity and pressure.

[0036] The visual tracking module features an RGB camera with a resolution of 1920×1080 pixels and a frame rate of 30 frames per second. Equipped with a wide-angle lens, it can cover the entire auricle and surrounding area. The RGB camera, along with the projector optical engine and structured light emitter, has undergone joint calibration before leaving the factory, resulting in precise camera intrinsic parameter matrices and rotation / translation matrices between the camera and projector. As the probe moves within the field of view, the RGB camera captures images containing the infrared tracking ring in real time. The infrared tracking ring appears as an ellipse (due to perspective projection) or a circle (when facing directly) in the image, with clear edges and high contrast, facilitating detection.

[0037] Please see Figure 3 The visual localization algorithm employs a hybrid approach combining a deep learning-based object detection model with geometric computation. First, the YOLOv8-Tiny lightweight object detection model is used to locate the bounding box of the infrared tracking loop in each frame. This model was trained on approximately 1000 labeled images, including the positions of the infrared tracking loop under different angles, distances, and lighting conditions. The trained model achieved a recognition accuracy exceeding 95% on the test set, with a processing speed exceeding 30 frames per second, meeting real-time requirements. After detecting the bounding box, the algorithm further extracts the precise contour of the tracking loop within the box, obtaining the center pixel coordinates of the tracking loop and the directions and lengths of the major and minor axes of the ellipse through ellipse fitting. Based on the shape parameters of the ellipse, the orientation angle of the tracking loop plane relative to the camera's optical axis can be inferred.

[0038] After obtaining the pixel coordinates (u, v) of the tracking loop center in the image, and combining this with the camera intrinsic parameter matrix K, the direction vector of the tracking loop center in the camera coordinate system can be calculated. Since monocular vision cannot directly obtain depth information, the system employs a depth estimation method based on prior size, specifically: Given that the true outer diameter of the infrared tracking ring is 10mm, the distance from the tracking ring to the camera is estimated using the principle of similar triangles based on the length of its major axis as an ellipse in the image. This method achieves a depth accuracy of ±2mm within a practical working distance (20 to 40cm). After obtaining the three-dimensional coordinates P_ring of the tracking ring center, the coordinates of the probe tip need to be further calculated. Given that the fixed distance from the tracking ring to the probe tip is 5mm, and the direction vector v is determined by the orientation obtained from ellipse fitting (i.e., the normal direction of the tracking ring plane, pointing towards the probe tip), the coordinates of the probe tip are P_tip = P_ring + 5mm·v.

[0039] When using the probe pen for the first time, the operator needs to place the pen tip on a known projection reference point (such as a standard acupoint light point just projected by the projector) and then press the confirmation button on the probe pen. The system records the coordinates of P_tip at this time as the reference origin and the corresponding position of the projection light point. Afterward, the system no longer relies on absolute spatial positioning but continuously updates the tip position by calculating the displacement vector of P_tip relative to the reference origin frame by frame. Displacement tracking uses a combination of optical flow and Kalman filtering to smooth and predict the position changes of the tracking loop between adjacent frames, maintaining the continuity of position estimation even under brief occlusion.

[0040] When the resistance detection circuit determines that the current contact point is a sensitive point, the system immediately calculates the corresponding pixel position on the projected screen based on the current P_tip coordinates, and drives the optical projection module to project a bright red dot at that position, flashing at 3Hz. Simultaneously, a vibration command is sent to the probe pen via Bluetooth, causing a flat linear vibration motor to vibrate continuously for 0.3 seconds, confirming the sensitive point detection through tactile feedback. This dual visual and tactile feedback allows the operator to easily locate the treatment point and directly apply ear seeds, perform acupuncture, or cupping at the illuminated spot. The system also automatically matches the coordinates of the sensitive point with its nearest standard acupoint, calculates the acupoint name, and records it in the patient's file for future treatment reference.

[0041] The attitude sensing module is a six-axis inertial measurement unit, integrating a three-axis accelerometer and a three-axis gyroscope. The accelerometer has a range of ±8g, and the angular velocity has a range of ±1000° / s. The system reads raw acceleration and angular velocity data at a sampling rate of 200Hz and outputs stable attitude quaternions through a Kalman filter fusion algorithm. Kalman filtering effectively suppresses sensor noise and drift, improving the accuracy of attitude estimation.

[0042] Please see Figure 4 The automatic compensation algorithm's workflow includes: Upon system startup, the operator maintains a natural head position. The IMU collects 100 data points and averages them as a reference attitude, represented by the quaternion q_ref. During subsequent operation, the system continuously calculates the current attitude quaternion q_cur. When the absolute value of any angular velocity axis exceeds 50° / s, or the change in any acceleration axis exceeds 0.5g, head movement is detected. At this point, the system initiates motion trajectory recording: the acceleration signal is double-integrated to obtain the head's displacements Δx, Δy, and Δz in three-dimensional space; simultaneously, the angular velocity signal is integrated to obtain the attitude angle change Δθ (represented by Euler angles, including yaw, pitch, and roll components). Considering that integration introduces cumulative errors, the system only records the trajectory within a short window from the start of motion to its stop, typically lasting no more than 2 seconds.

[0043] When the outputs of the gyroscope and accelerometer return to a stationary state, and the Euler angle difference between the current attitude q_cur and the reference attitude q_ref is less than 5°, the system determines that the head has been reset. At this time, based on the recorded displacement trajectory (Δx, Δy, Δz) and angle change Δθ, the projection compensation matrix is ​​calculated. The projection optical engine is installed inside the main unit, and its projection direction can be adjusted within a small range by driving a micro motor. The system calculates a compensation rotation matrix R_comp, so that the compensated projection optical path can be aligned with the reset target area. At the same time, the offset of the projected image is adjusted according to the displacement vector. The entire compensation process is completed within 0.3 seconds, and the operator can hardly feel the interruption of the projection. Meanwhile, the infrared ranging sensor will trigger an autofocus after the attitude compensation is completed to ensure that the projection is clear.

[0044] The control and communication module uses a high-performance AR-type SoC as the main control chip. This chip integrates a quad-core ARM architecture central processing unit and a neural network processing unit, enabling it to run complex tasks such as the operating system, visual tracking algorithms, and surface fitting algorithms in parallel. The memory configuration includes 4GB of LPDDR4 RAM and 32GB of eMMC flash storage for storing program code, patient record data, and various preset acupoint models and prescription libraries.

[0045] In terms of wireless communication, the system supports Bluetooth Low Energy 5.0 and WiFi 802.11ac protocols. Bluetooth is used to transmit control commands, such as short messages for mode switching, prescription retrieval, and volume adjustment; WiFi is used to transmit large amounts of patient files, including 3D point cloud data and projection screenshots. The microphone is a MEMS silicon microphone with an omnidirectional pickup design for receiving the operator's voice commands. The speaker is used to issue voice prompts, such as "Disinfection complete," "Switch to teaching mode," and "Sensitive points saved." Physical buttons include a power switch and two touch switches for mode switching, located on the side of the projector for easy blind operation.

[0046] The mobile app converts the user's voice commands into text using the phone's voice recognition engine, then parses the specific control commands using an intent classification model, and finally sends them to the projector via Bluetooth. The intent classification model supports various commands, including mode switching, prescription retrieval, projection control, patient operation, teaching functions, and device control. The mobile app also has a built-in standardized prescription library, covering commonly used clinical combinations such as laxatives (large intestine, rectum, triple burner, lung, constipation point), antiemetics (stomach, cardia, shenmen, sympathetic), and calming formulas (shenmen, heart, kidney, subcortex), and supports custom prescriptions and prescription sharing. The patient profile module stores 3D point cloud data, projection screenshots, sensitive point coordinates, matching acupoint names, treatment time, and prescription information for each treatment, indexed by patient ID. During follow-up visits, simply retrieving the patient's name via voice will automatically complete the registration and restoration process.

[0047] The power module of this invention uses a soft-pack lithium-ion battery with a rated capacity of 2000 mAh, a typical voltage of 3.7 volts, and a size of approximately 50mm × 40mm × 5mm, which can be easily embedded inside the projector host.

[0048] This invention features symmetrically arranged foldable magnifying lenses on both sides of the projector, allowing the lenses to remain at any angle within a range of 0 to 180 degrees. The magnifying lens lenses are made of optical resin material, with an aspherical design to effectively eliminate edge aberrations. They have a diameter of 25mm and a magnification of 2 to 3 times. When the operator unfolds either side of the magnifying lens, a built-in Hall sensor detects a change in the magnetic field, and the system automatically illuminates two white LED patches to provide supplementary lighting, ensuring sufficient light within the magnified field of view. After use, the magnifying lenses can be folded back to the side of the projector, without taking up extra space or affecting the projection light path.

[0049] This invention provides a comparative example: This example compares the performance of the present invention with existing projection-based auricular acupoint localization devices in the same clinical simulation environment. The experimental subjects were 36 volunteers (as patient models), randomly divided into two groups, A and B, with 18 volunteers in each group. There were no statistically significant differences in age and gender distribution between the two groups. The operators were six nurses with more than three years of clinical experience in auricular acupressure. Each nurse performed auricular acupoint localization on the randomly assigned volunteers using both the present invention and traditional methods. The operation sequence employed a randomized crossover design to eliminate the learning effect (each nurse first used the present invention on half of the volunteers and the traditional method on the other half, then switched methods after one week, repeating the operation; each volunteer received two localizations (one week apart), but both localizations were performed by the same nurse).

[0050] (1) In this experiment, a panel of three senior TCM experts (all with over 10 years of experience in auricular acupuncture and not involved in the localization procedures) jointly determined the gold standard anatomical locations of 10 representative acupoints on the auricle of each volunteer using a blind method. The expert panel observed and palpated anatomical landmarks with a magnifying glass and marked the gold standard points on the volunteers' auricles with a medical skin marker pen, referring to the "Auricular Acupoint Names and Locations" standard. Then, the acupoints on the same side of the auricle of the same volunteer were located using both the device of this invention and the traditional method. The Euclidean distance between the device-indicated location (the center of the projected light point in this invention, and the optimal location point determined by the operator using a regular probe pen in the traditional method) and the gold standard point was measured in mm. Each acupoint was measured three times and the average value was taken. The results are shown in Table 1: Table 1. Accuracy of acupoint location (p<0.001)

[0051] As shown in Table 1, the average positioning error of the present invention is 1.57 mm, and the maximum error is 2.0 mm, while the average positioning error of the traditional method is 5.41 mm, and the maximum error is 7.0 mm. The positioning accuracy of the present invention is improved by approximately 71% (error reduced by 3.84 mm) compared to the traditional method, and the dispersion of the error is smaller. This indicates that the present invention can provide stable and accurate positioning guidance for operators with different auricle shapes, while the traditional method is greatly affected by operator experience, visual deviation, and individual differences in auricle shape.

[0052] (2) In 10 standard acupoint areas (10 acupoints on the right ear), the expert group used a high-precision scientific research-grade electrical impedance to scan each volunteer in advance, and confirmed acupoints with a resistance reduction of more than 30% as "true sensitive points". The criteria for judging a sensitive point are: compared with the normal skin reference resistance of the earlobe, the resistance value decreases by ≥30% and remains stable for more than 1 second. The expert group confirmed the distribution of sensitive points of 36 volunteers, with a total of 247 true sensitive points (an average of about 6.86 points per volunteer). Then, the operator used the present invention and the traditional method to detect sensitive points for each volunteer, and recorded the number of sensitive points that the operator actually successfully detected (the operator made a bean-sticking or marking action at the location, and the location was verified to be a true sensitive point afterward). Detection rate = number of successfully detected points / total number of true sensitive points of the volunteer × 100%.

[0053] Table 2. Sensitive point detection rate (p<0.001)

[0054] As shown in Table 2, the detection rate of sensitive points in the present invention group was 95.1%, while that of the traditional method group was 70.0%. The present invention improved the detection rate of sensitive points by 25.1 percentage points. In the traditional method, the operator can only rely on auditory feedback (beeping sound). During the detection process, the operator needs to keep the probe stable and simultaneously remember the probe position when the beeping sound is heard. Then, the operator needs to look up and observe the anatomical structure of the auricle to confirm the acupoint name. This process is very prone to missed detections or misjudgments due to probe slippage, memory deviation, or misidentification of auricle anatomy. In contrast, the present invention projects sensitive points as red flashing dots on the skin surface in real time. The operator can mark them directly without shifting their gaze, completely avoiding errors caused by position memory and spatial transformation, thereby significantly improving the detection rate.

[0055] (3) The NASA Mission Load Index was used to quantitatively assess the operators' subjective workload. This index comprises six dimensions: mental workload, physical workload, time workload, self-performance, effort level, and frustration. Each dimension has a score range of 0 to 100, and the total score is the arithmetic mean of the six dimensions (after weighting). A higher score indicates a greater cognitive workload. After the experiment, the six operators completed the index for both methods, and each person evaluated each method once.

[0056] Table 3. Operator cognitive load (p<0.001)

[0057] As shown in Table 3, the total cognitive load score for the invention group was only 24.3 points, significantly lower than the 55.7 points of the traditional method group. Operators generally reported that using the traditional method required constantly switching their gaze between the atlas and the patient's auricle, memorizing the correspondence between acupoint names and anatomical locations, and carefully controlling the scanning path of the probe pen to avoid omissions; the entire process was highly stressful. In contrast, using the invention, the projected light directly indicates the location, and sensitive points automatically illuminate. The operator only needs to move the probe pen to the illuminated area, requiring almost no mental memorization or spatial maneuvering, making the operation easy and smooth. This result demonstrates the significant advantage of the invention in reducing the operator's cognitive burden.

[0058] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure, characterized in that, include: Headband-style support for wearing on the operator's head; The projector, mounted on a head-mounted stand, includes an optical projection module, a visual tracking module, and a 3D scanning module. The intelligent probe pen communicates wirelessly with the projector host. The probe base of the probe pen is equipped with an infrared tracking ring. The intelligent probe pen has a built-in resistance detection circuit to detect the resistance value of the skin that the probe tip contacts in real time. The visual tracking module includes an RGB camera, which captures images containing an infrared tracking ring in real time and calculates the real-time position coordinates of the probe tip in three-dimensional space using a visual positioning algorithm. During the acupoint location operation, the projector converts the real-time position coordinates of the probe tip of the probe pen into a projection point, and then projects the projection point onto the acupoint target position on the patient's body surface observed by the operator through the optical projection module. When the resistance detection circuit detects that the change in the current skin resistance value compared to the reference resistance value exceeds a preset threshold, it determines that a sensitive point has been detected. The projector then changes the display attributes of the projected light point projected onto that location to create visual feedback.

2. The head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure, as described in claim 1, is characterized in that: The 3D scanning module of the projection host includes a structured light emitter and an infrared camera. During the first treatment, the structured light emitter projects structured light onto the patient's acupoints, and the infrared camera captures the structured light images to generate 3D point cloud data of the acupoints. A non-rigid registration algorithm is used to fit the preset standard 3D model of the acupoints with the 3D point cloud data of the acupoints to the surface, calculate the actual projection coordinates of each acupoint on the individual, and drive the optical projection module to accurately project the acupoint mark to the corresponding position.

3. A head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure, as described in claim 1, characterized in that: The resistance detection circuit of the probe applies a constant microcurrent to the probe, the reference resistance value is the resistance value of the patient's normal skin area, and the preset threshold is when the resistance value decreases by more than 30%; When a point is identified as a sensitive point, the projector controls the projected light point to highlight it by differentiating its color and / or flashing frequency from that of a non-sensitive point. At the same time, the vibration motor built into the probe pen generates vibration feedback.

4. A head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure, as described in claim 1, characterized in that, The projection host achieves real-time dynamic tracking of the projected light spot through the following steps: S1, place the probe tip of the probe pen on a known projection reference point, press the confirmation button on the probe pen, and the system records the three-dimensional spatial coordinates of that point as the reference origin; S2, the visual positioning algorithm calculates the displacement vector of the probe tip relative to the reference origin in real time by combining the position change of the infrared tracking ring in continuous frame images with the geometric parameters of the probe pen; S3, based on the displacement vector, updates the current spatial coordinates of the probe tip in real time, and drives the optical projection module to project the projection light spot to the corresponding new position.

5. A head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure, as described in claim 1, characterized in that: The projection host also integrates an attitude sensing module, which includes a six-axis inertial measurement unit. This attitude sensing module is used to monitor the operator's head posture changes in real time. When the head displacement is detected and the head is reset, the system calculates and performs projection angle compensation based on the recorded displacement trajectory, thereby restoring projection alignment within a preset time.

6. A head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure, as described in claim 1, characterized in that: The system has a treatment mode and a teaching mode. When the projector is removed and placed on the table, it can be switched to the teaching mode. In the teaching mode, the image projected by the optical projection module includes not only the location of acupoints, but also the associated text information, which includes the name of the acupoint, the meridian to which it belongs, and its main functions.

7. A head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure, as described in claim 1, characterized in that: The system also includes a mobile terminal APP that communicates wirelessly with the projector host. The mobile terminal APP is used to receive voice commands and convert them into control signals to send to the projector host, thereby controlling the operation of the projector host. The mobile app is also used to create and store patient files, which include at least 3D scan data generated during historical treatments, screenshots of acupoint projections, and coordinates of detected sensitive points. During follow-up visits, by retrieving the patient files, the projection host will register the historical 3D data with the current patient's body surface to restore the acupoint projection positions from the last treatment.

8. A head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure, as described in claim 1, characterized in that: The body of the intelligent detection pen is detachably connected to the probe, which includes a probe base made of high-temperature and high-pressure sterilization material, a metal probe, and an infrared tracking ring fixed to the root of the probe.

9. A head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure, as described in claim 1, characterized in that: The projector is equipped with foldable magnifying glasses on both the left and right sides. Each magnifying glass is surrounded by LED lights. When the magnifying glass is unfolded, the projector lights up the LED lights. When the magnifying glass is folded, it is stored in the side of the projector.

10. A head-mounted intelligent projection navigation system for assisting in the location of acupoints in traditional Chinese medicine therapies such as auricular acupressure, according to any one of claims 1-9, characterized in that: The system is used to assist in the location of acupoints, display of meridian pathways, or planning of operation paths in acupuncture, massage, or cupping therapy. Different therapies correspond to different preset projection maps, which include acupoint arrays, meridian lines, or cupping coverage areas.

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