Double-bending flexible lens system for gastrointestinal tract examination and control method

Abstract

The invention discloses a double-bending soft lens system for gastrointestinal tract examination, which comprises a near-end active bending section, a far-end passive bending section and a modal imaging module, and is characterized in that the system combines a high-resolution double-modal imaging technology and a mechanical strengthening structure design through an active and passive double-bending collaborative mechanism; according to the flexible endoscope, the contradiction between the view blind area problem of a traditional hard endoscope in gastrointestinal tract examination and insufficient mechanical property of a soft endoscope is solved, the near-end active bending section is driven by shape memory alloy, and multi-degree-of-freedom accurate control bending is achieved. By combining shape memory alloy precision driving, a composite material mechanical strengthening structure, a far-end superelastic framework and a limiting protection mechanism, the operation flexibility and the structural stability of the flexible endoscope system in a gastrointestinal tract complex anatomical area are effectively improved, and the risks of view blind areas, endoscope body collapse, twisting and the like are remarkably reduced.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to a double-curved flexible endoscope system and control method for gastrointestinal examinations, which is particularly suitable for high-precision diagnostic and treatment scenarios such as gastroduodenoscopy / colonoscopy, early tumor screening, and exploration of narrow areas in the digestive tract. Background Technology

[0002] Since the advent of fiber optic endoscopes in the 1950s, gastrointestinal endoscopy has gradually evolved from a diagnostic tool into a minimally invasive interventional system integrating diagnosis and treatment. Early rigid endoscopes, unable to adapt to the tortuous anatomy of the gastrointestinal tract, were only suitable for examining short, straight lumens such as the esophagus and rectum. In the 1980s, the widespread adoption of electronic endoscopes enabled digital imaging, and combined with flexible endoscope designs, significantly improved the visualization capabilities of complex cavities such as the stomach and colon. However, existing flexible endoscope systems still face significant bottlenecks in accurately locating early, small lesions (≤5mm) and coordinating the operation of treatment instruments, particularly in addressing anatomical variations in the gastrointestinal tract (such as redundant colons and duodenal bends). Specifically, this manifests as a contradiction between blind spots and operational flexibility: traditional single-bend flexible endoscopes can only achieve unidirectional bending (such as up / down or left / right), making it difficult to simultaneously adjust multiple lesions in tortuous intestines. The planar angle leads to insufficient exposure of some intestinal loops (such as the hepatic and splenic flexures of the colon), resulting in a missed diagnosis rate as high as 15%-25%; insufficient mechanical performance: the torsional strength of existing flexible endoscopes is generally ≤10N·cm, which easily causes the endoscope to twist and knot when passing through narrow or adherent areas of the intestine, and even leads to mucosal tearing (incidence rate of 0.3%-0.8%); limitations in imaging resolution and dynamic tracking: the resolution of mainstream high-definition endoscopes is mostly 1080p, which is insufficient for the boundary identification of early flat lesions (such as laterally developing tumors LST), and lacks real-time blood perfusion assessment function, making it difficult to distinguish between inflammatory lesions and neoplastic lesions; poor instrument channel coordination: when treatment accessories (such as biopsy forceps, electrocoagulation knife) are operated coaxially with the endoscope, the field of view is easily obstructed or limited by the bending angle of the endoscope, resulting in a decrease in treatment accuracy (such as incomplete lesion lifting during EMR). In recent years, attempts to improve related technologies have included: robot-assisted endoscopy systems, such as helical propulsion colonoscopes, which use external motors to drive the endoscope to rotate and move forward. However, these systems are bulky (diameter ≥18mm), cannot pass through narrow lesion segments, and increase costs by 3-5 times; capsule endoscopy, which achieves non-invasive imaging of the entire small intestine, but cannot actively control the direction of movement, has a lesion localization error ≥20mm, and lacks therapeutic functions; and confocal laser microscopy, which can provide mucosal cell-level resolution, but has limited imaging depth (≤250μm) and cannot be performed simultaneously with treatment procedures. With the increasing demand for early gastrointestinal cancer screening (the early diagnosis rate of gastric and colorectal cancer in my country is less than 30%), there is an urgent clinical need for a new flexible endoscopy system with the following characteristics: multi-degree-of-freedom active-passive coordinated bending: breaking through the limitations of single-degree-of-freedom bending, achieving "S"-shaped adaptive fitting of the endoscope in the tortuous sections of the intestine; high-strength anti-torsion structure: the torsional stiffness of the endoscope is ≥20 N·cm, and the axial compressive strength is ≥30 N / cm², avoiding deformation or damage during operation; multi-modal fusion imaging: supporting 4K white light, narrow-band imaging (NBI), and laser speckle blood flow monitoring, realizing three-dimensional diagnosis of "morphology-vascular-function"; intelligent instrument coordination channel: equipped with independent flushing, suction, and instrument guidance functions, reducing operational interference and improving treatment efficiency. Summary of the Invention

[0003] This invention provides a double-curved flexible endoscope system and control method for gastrointestinal examination, which can effectively solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a dual-bending flexible endoscope system for gastrointestinal examination, comprising a proximal active bending segment, a distal passive bending segment, and a modal imaging module; The system solves the contradiction between the blind spots in the field of view of traditional rigid endoscopes and the insufficient mechanical performance of flexible endoscopes by combining a "active and passive" dual-bending collaborative mechanism with high-resolution dual-modal imaging technology and mechanically reinforced structural design. The proximal active bending section is driven by a shape memory alloy to achieve precise multi-degree-of-freedom bending control; The distal passive bending section is a hyperelastic structure with adaptive properties, possessing high bending compliance and limiting protection functions. The modal imaging module integrates white light imaging and near-infrared fluorescence navigation functions, and combined with AI enhancement algorithms, it can achieve high-definition, low-latency image acquisition and augmented reality-assisted display in complex gastrointestinal environments.

[0005] According to the above technical solution, the core material of the driving structure of the proximal active bending segment is a shape memory alloy driving wire: a Ni-Ti-Cu ternary alloy with a diameter of 0.15 mm and a phase transformation temperature of 42℃. The drive wire layout consists of 3 drive wires evenly distributed in a 120° circumferential direction, with each wire spaced 2 mm apart and arranged in parallel, for a total length of 300 mm. The control mechanism adopts current drive. A current of 0.8-1.2A is applied to one or more drive wires through the PID temperature control circuit to trigger the martensite → austenite phase transformation. The shrinkage rate of the drive wire is 8.5%. The bending angle calculation formula is: θ=(ΔL / r)×(180 / π) Multi-degree-of-freedom bending: By combining the drive wires at different positions, single-plane bending can be achieved. Composite planar bending, with each set of drive filaments connected to an independent temperature control circuit at the end, triggers phase change through Joule heating, with a single filament shrinkage rate ≥8%, achieving ±180° active bending; The bending control logic is as follows: a. Single-sided drive wire heating: The mirror body bends in the corresponding direction; b. Dual-sided drive wire synergistic heating: achieving composite planar bending.

[0006] According to the above technical solution, the mechanical reinforcement of the proximal active bending section adopts a multi-layer composite design: inner layer: polyimide-based tube, providing insulation and high temperature resistance; Middle layer: 316L stainless steel woven mesh, with compressive strength increased to 60N / cm² and torsional stiffness ≥0.15N·m / rad; Outer layer: Medical-grade silicone, coated with a silver-loaded nano-TiO2 coating, with an antibacterial rate of ≥99.9%; The middle layer is nested with stainless steel woven mesh to enhance torsional and compressive strength; The outer layer is covered with medical-grade silicone, and the surface is coated with a silver-loaded nano-titanium dioxide antibacterial coating to inhibit intraoperative infection.

[0007] According to the above technical solution, the distal passive bending section is an adaptive skeleton, which adopts a superelastic nickel-titanium alloy skeleton: the Ni-Ti alloy tube is processed by laser cutting to form a rhomboid hollow unit with a hollowing rate of 65% and a maximum allowable bending radius of 5mm. After heat treatment, the hyperelastic strain recovery rate of the skeleton is ≥98%. Silicone coating: Double-layer injection molding: the inner layer is high-adhesion silicone, and the outer layer is wear-resistant silicone, with a total thickness of 0.5mm; Surface micro-texturing: laser engraving of transverse ripples.

[0008] According to the above technical solution, the limiting protection mechanism of the remote passive bending section is a mechanical limiter: titanium alloy spring plates are embedded in the 5th, 10th and 15th hollow units of the skeleton. When the bending angle exceeds 270°, the spring plates contact the adjacent units to limit further bending. Limit trigger force ≥0.5N to avoid false triggering; Optical self-testing system: integrates a miniature fiber optic grating sensor to monitor bending strain in real time and trigger an audible and visual alarm when the limit is exceeded.

[0009] According to the above technical solution, the modal imaging module integrates white light 4K imaging and near-infrared fluorescence navigation functions. Through intelligent switching and AI enhancement technology, the following is a detailed technical breakdown of the module: Optical system hardware design: Dual sensor side-by-side layout: 4K CMOS sensor: Model: Sony IMX585, 1 / 1.8-inch back-illuminated sensor, effective pixels 3840×2160, pixel size 1.4μm; Dynamic range: 85dB, supports 60fps full resolution output; Spectral response: 400-700nm, equipped with a sapphire protective window; Near-infrared fluorescence sensor: InGaAs focal plane array, response band 800-1700nm; Integrated narrowband filter to suppress background noise; Spectroscopic prism system: adopts dichroic prism, with a reflection band of 800-850nm and a transmission band of 400-700nm; After the white light and fluorescent light paths are separated, they are projected onto the CMOS and InGaAs sensors respectively to achieve dual-channel synchronous acquisition; Lighting system: White light illumination: High color rendering LED array, power 2W, light is guided to the front end through a flexible optical fiber bundle; Ring-shaped layout, uniformity ≥90%; Fluorescent excitation source: near-infrared laser diode, modulation frequency 1kHz, to avoid tissue thermal damage; When compatible with ICG developer, the excitation efficiency is ≥85%; Fiber optic image bundle: Structural parameters: The flexible fiber bundle has a diameter of 2mm, the single filament has a diameter of 10μm, and the arrangement is hexagonal close packing; Numerical aperture NA=0.4, transmittance ≥70%; Anti-bending design: The outer layer of the fiber bundle is coated with an elastic polyurethane sheath, with a minimum bending radius of 3mm and a transmission loss of ≤3dB.

[0010] According to the above technical solution, the imaging mode switching and control of the modal imaging module adopts a dual-modal workflow: White light mode: By default, the white light LED is turned on, and the CMOS sensor acquires visible light images for anatomical structure observation; Resolution: 3840×2160@60fps, latency ≤30ms; Fluorescence mode: After ICG injection, a near-infrared laser is activated, and the InGaAs sensor captures the fluorescence signal; Real-time display of blood flow in blood vessels, with a switching time of ≤100ms; Intelligent switching logic: Manual switching: The operator can switch modes instantly via the handle buttons; Automatic trigger: When the AI ​​algorithm detects bleeding or the need for vascular visualization, the fluorescence mode is automatically activated.

[0011] According to the above technical solution, the AI ​​image enhancement and processing employs motion blur compensation: Algorithm architecture: Based on U-Net convolutional neural network, the input is 3 consecutive frames of images, and the output is a motion vector field; Dynamically corrects pixel displacement caused by gastrointestinal peristalsis, with a compensation accuracy of ±0.5 pixels; Real-time performance: Deployed on FPGA, processing latency ≤8ms; Supports real-time processing at 1080p@120fps; Enhanced vascular margins: Multi-scale feature fusion: extract the vascular skeleton from the fluorescence image and enhance the edges through the Laplacian operator and morphological closing operation; Superimposed on a white light image to form an augmented reality view, with a blood vessel contour accuracy of ±0.1mm; Adaptive noise reduction: Noise Model: A hybrid noise model is established based on the characteristics of endoscopic images; Based on wavelet transform and BM3D algorithm, the signal-to-noise ratio is improved by ≥15dB.

[0012] According to the above technical solution, a control method for a double-bend flexible endoscope system for gastrointestinal examination is provided. The master-slave control system achieves precise control of the double-bend flexible endoscope through biomimetic design, multi-degree-of-freedom control and real-time force feedback mechanism, solving the control delay and positioning drift problems caused by the flexible deformation of traditional flexible endoscopes. The following are the core components and technical details of the system: System architecture and working principle: Master-slave control logic: Master end: Receives the operator's operation instructions and encodes them as digital signals; Slave end: decodes signals and drives the mirror body to bend, rinse, and image, while transmitting force and visual feedback back to the master end; closed-loop control cycle: ≤10ms; Kinematic mapping: Establish the mapping relationship between the mirror body's two-segment bending model and the controller's joystick: joystick X / Y axis, pitch / yaw of the proximal active segment; Knob angle and remote passive section curvature adjustment; foot pedal and flushing / sucking intensity; Main console design: Handheld controller: Three-axis force feedback joystick: adopts magnetorheological damper, output force range 0.1-5N, resolution 0.01N; joystick deflection angle ±30°, accuracy ±0.1°, equipped with thumb touch screen to display the mirror body posture in real time; Multi-function buttons: Mode switching button: white light / fluorescence imaging, continuous / pulse washing; Emergency return button: one-button straightening of the scope; Visual feedback system: 3D stereoscopic display: 4K OLED screen, polarized light imaging technology, providing naked-eye 3D effect; integrated AR navigation: fluorescently visualized blood vessel outlines are superimposed on white light images, with adjustable transparency; Design of the actuator from the end: Robot drive unit: Multi-degree-of-freedom robotic arm: a six-axis collaborative robot with a load capacity of ≥5kg and an end effector with a flexible end effector interface; the kinematic model is based on DH parameters, and the inverse kinematics algorithm calculates joint angles in real time. SMA drive control module: high-frequency pulse power supply, independently controls the heating power of 3 sets of SMA drive wires; temperature-resistance closed-loop feedback to prevent overheating damage; Sensor fusion system: Pose sensor: Fiber grating array: embedded near the mirror body to monitor bending angle in real time; IMU: Sampling rate 1kHz, detects overall movement of the mirror body; Force tactile sensor: a miniature MEMS six-dimensional force sensor integrated at the distal end of the mirror body; A tactile alarm is triggered when the contact force exceeds the limit.

[0013] According to the above technical solution, the security protection mechanism includes: Over-limit emergency braking: When the bending angle is greater than 270° or the contact force is greater than 2N, the SMA drive power is cut off and the mirror body retraction is initiated; Sterile barrier: Wireless communication is used between the master and slave ends, and physical isolation is used to avoid contamination; Self-test and calibration: Automatically performs zero-position calibration of the mirror body and sensor calibration upon power-on.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention has a scientific and reasonable structure and is safe and convenient to use. By constructing an "active and passive" double-bending flexible endoscope, combined with shape memory alloy precision drive, composite material mechanical reinforcement structure, and distal superelastic skeleton and limiting protection mechanism, the flexible endoscope system can effectively improve the operational flexibility and structural stability of the complex anatomical area of ​​the gastrointestinal tract, significantly reduce the risk of blind spots and endoscope collapse, twisting, etc. The active section can achieve ±180° multi-degree-of-freedom bending, and the passive section has an adaptive curvature of up to 270°. With the help of fiber optic grating monitoring and mechanical limiter, it ensures high compliance and safety in dynamic operation, and is suitable for high-risk areas such as intestinal loops and stricture lesions. Meanwhile, this invention achieves integrated innovation in imaging and control systems. The dual-modal imaging module supports simultaneous acquisition of 4K white light and near-infrared fluorescence, combined with AI image enhancement algorithms, AR vascular navigation, and real-time noise reduction processing, improving the ability to identify early micro-lesions and perform functional diagnosis. The master-slave control system, based on force feedback, 3D stereo vision, and biomimetic mapping mechanisms, significantly enhances control precision and response speed. Furthermore, through wireless isolation, automatic homing, and overload protection mechanisms, it improves the overall intelligence level and surgical safety assurance capabilities, and has broad prospects for clinical application and industrialization. Attached Figure Description

[0015] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0016] In the attached diagram: Figure 1 This is a schematic diagram of the overall structure of the double-curved flexible mirror of the present invention; Figure 2 This is a schematic diagram of the cross-section of the proximal segment of the mirror body of the present invention; Figure 3 This is a schematic diagram of the double-bending state of the present invention; The following are labeled in the diagram: 1. Super-elastic nickel-titanium alloy skeleton; 2. Silicone; 3. Rhomboid hollow unit; 4. Stainless steel textured tube; 5. Fiber optic cable bundle; 6. Imaging module; 7. Rinsing tube; 8. Suction tube; 9. SMA-1; 10. SMA-2; 11. SMA-3. Detailed Implementation

[0017] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0018] Example 1: A dual-bending flexible endoscope system for gastrointestinal examination includes a proximal active bending segment, a distal passive bending segment, and a modal imaging module. The system solves the contradiction between the blind spots in the field of view of traditional rigid endoscopes and the insufficient mechanical performance of flexible endoscopes by combining a "active and passive" dual-bending collaborative mechanism with high-resolution dual-modal imaging technology and mechanically reinforced structural design. The proximal active bending section is driven by a shape memory alloy to achieve precise multi-degree-of-freedom control of bending; The distal passive bending section is a hyperelastic structure with adaptive properties, possessing high bending compliance and limit protection functions; The modal imaging module integrates white light imaging and near-infrared fluorescence navigation functions, combined with AI enhancement algorithms, to achieve high-definition, low-latency image acquisition and augmented reality-assisted display in complex gastrointestinal environments, thereby improving the visibility, accuracy and safety of gastrointestinal endoscopic operations.

[0019] According to the above technical solution, the core material of the driving structure of the proximal active bending segment is a shape memory alloy (SMA) driving wire: a Ni-Ti-Cu ternary alloy (atomic ratio Ni:Ti:Cu=50:47:3) with a diameter of 0.15mm and a phase transformation temperature of 42℃ (Af point). Compared to traditional Ni-Ti alloys, the addition of copper can improve the response speed (heating to the phase transition temperature takes only 1.2 seconds). The drive wire layout consists of three drive wires evenly distributed in a 120° circumferential direction, with each wire spaced 2 mm apart and arranged in parallel, for a total length of 300 mm (covering a 150 mm section near the end of the microscope body).

[0020] The control mechanism employs current drive, applying a 0.8-1.2A current to one or more drive wires via a PID temperature control circuit (accuracy ±0.5℃), triggering the martensite → austenite phase transformation. The drive wire shrinkage rate is 8.5%. The bending angle is calculated using the formula: θ = (ΔL / r) × (180 / π)(ΔL / r) × (180 / π ... L This refers to the shrinkage of the driving filament. r Multi-degree-of-freedom bending (with a mirror body radius of 3mm): By combining SMA wires driven at different positions, single-plane bending (such as to the left / right / forward / backward) can be achieved. Composite planar bending (e.g., 30° forward left + 15° upward), each set of drive wires is connected to an independent temperature control circuit at the end, and phase change is triggered by Joule heating (current 0.8-1.2A), with a single filament shrinkage rate ≥8%, achieving ±180° active bending; The bending control logic is as follows: a. Single-sided drive wire heating: The mirror body bends in the corresponding direction (e.g., left-side drive wire heating → left deflection); b. Dual-sided drive wire coordinated heating: to achieve composite planar bending (e.g., left + front drive wire heating → left front 45° bending).

[0021] According to the above technical solution, the mechanical reinforcement of the proximal active bending section adopts a multi-layer composite design: inner layer: polyimide base tube (wall thickness 0.1mm), which provides insulation and high temperature resistance (withstands ≥200℃). Middle layer: 316L stainless steel woven mesh (80% coverage, 54.7° weaving angle), compressive strength increased to 60N / cm², torsional stiffness ≥0.15N·m / rad; Outer layer: Medical-grade silicone (Shore hardness 40A, thickness 0.3mm), surface coated with silver-loaded nano-TiO2 coating (silver content 2wt%), antibacterial rate ≥99.9%; The middle layer is nested with stainless steel woven mesh (80% coverage, 0.05mm wire diameter) to improve torsional and compressive strength (axial compressive strength ≥50N / cm²). The outer layer is covered with medical-grade silicone (Shore hardness 40A), and the surface is coated with a silver-loaded nano-titanium dioxide antibacterial coating to inhibit intraoperative infection.

[0022] According to the above technical solution, the remote passive bending section is an adaptive skeleton, which adopts a superelastic nickel-titanium alloy skeleton: the Ni-Ti alloy tube (outer diameter 6mm, wall thickness 0.2mm) is processed by laser cutting process (fiber laser, wavelength 1064nm) to form a rhomboid hollow unit (size 1mm×0.5mm), with a hollowing rate of 65% and a maximum allowable bending radius of 5mm (corresponding to a bending angle of 270°). After heat treatment (annealing at 500℃ for 30 minutes), the hyperelastic strain recovery rate of the skeleton is ≥98% (ASTM F2082 standard). Silicone coating: Double-layer injection molding: the inner layer is high-adhesion silicone (Shore hardness 30A), and the outer layer is wear-resistant silicone (Shore hardness 50A), with a total thickness of 0.5mm; Surface micro-texturing treatment: Laser engraving of transverse ripples (depth 50μm, spacing 0.5mm) to reduce the coefficient of friction with myocardial tissue (μ≤0.15).

[0023] According to the above technical solution, the limiting protection mechanism of the remote passive bending section is a mechanical limiter: titanium alloy spring sheets (thickness 0.1mm) are embedded in the 5th, 10th and 15th hollow units of the skeleton. When the bending angle exceeds 270°, the spring sheets contact the adjacent units to limit further bending. Limit trigger force ≥0.5N to avoid false triggering; Optical self-testing system: integrates a miniature fiber optic grating sensor (FBG, wavelength 1550nm) to monitor bending strain in real time and trigger an audible and visual alarm when the strain exceeds the limit (threshold is set to strain ≥8%).

[0024] Based on the above technical solution, the modal imaging module integrates white light 4K imaging and near-infrared fluorescence navigation functions. Through intelligent switching and AI enhancement technology, it provides a stable and high-resolution field of view in the dynamic environment of the gastrointestinal tract, meeting the precise operation requirements of gastroscopy and colonoscopy. The following is a detailed technical breakdown of the module: Optical system hardware design: Dual sensor side-by-side layout 4K CMOS sensor: Model: Sony IMX585, 1 / 1.8-inch back-illuminated sensor, effective pixels 3840×2160, pixel size 1.4μm; Dynamic range: 85dB, supports 60fps full resolution output; Spectral response: 400-700nm (visible light band), equipped with a sapphire protective window (0.3mm thick); Near-infrared fluorescence sensor: InGaAs focal plane array (640×512 pixels), response band 800-1700nm; Integrated narrowband filter (center wavelength 830nm, bandwidth ±10nm) to suppress background noise; Spectroscopic prism system: adopts a dichroic prism, with a reflection band of 800-850nm and a transmission band of 400-700nm; After the white light and fluorescent light paths are separated, they are projected onto the CMOS and InGaAs sensors respectively to achieve dual-channel synchronous acquisition; Lighting system: White light illumination: High color rendering LED array (CCT5500K, Ra≥95), power 2W, light is guided to the front end through a flexible fiber optic bundle; Annular layout (4mm in diameter), uniformity ≥90% (tested according to ANSI standard); Fluorescence excitation source: near-infrared laser diode (wavelength 805nm, power 50mW), modulation frequency 1kHz, to avoid tissue thermal damage; When matched with ICG developer (absorption peak 805nm, emission peak 830nm), the excitation efficiency is ≥85%; Fiber optic image bundle: Structural parameters: flexible fiber bundle diameter 2mm, single filament diameter 10μm, arranged in hexagonal close packing (20,000 pixels). Numerical aperture NA=0.4, transmittance ≥70% (wavelength 400-850nm); Anti-bending design: The outer layer of the fiber bundle is coated with an elastic polyurethane sheath (0.1mm thick), with a minimum bending radius of 3mm (corresponding to a bending angle of 180° for the lens body) and a transmission loss of ≤3dB.

[0025] According to the above technical solution, the imaging mode switching and control of the modal imaging module adopts a dual-modal workflow: White light mode: By default, the white light LED is turned on, and the CMOS sensor acquires visible light images for anatomical structure observation; Resolution: 3840×2160@60fps, latency ≤30ms; Fluorescence mode: After ICG injection (dose 0.1 mg / kg), a near-infrared laser is activated, and the InGaAs sensor captures the fluorescence signal; Real-time display of blood flow in blood vessels, with a switching time of ≤100ms; Intelligent switching logic: Manual switching: The operator can switch modes instantly via the handle buttons; Automatic trigger: When the AI ​​algorithm detects bleeding (sudden increase in blood color saturation in the image) or when vascular visualization is required, the fluorescence mode is automatically activated.

[0026] Based on the above technical solution, AI image enhancement and processing employs motion blur compensation: Algorithm architecture: A convolutional neural network based on U-Net, with input being three consecutive frames of images (interval 16.7ms) and output being a motion vector field; Dynamically corrects pixel displacement caused by gastrointestinal peristalsis, with a compensation accuracy of ±0.5 pixels; Real-time performance: Deployed on FPGA (Xilinx Zynq UltraScale+), processing latency ≤8ms; Supports 1080p@120fps real-time processing (downsampling mode); Enhanced vascular margins: Multi-scale feature fusion: Extract the vascular skeleton (diameter ≥ 0.5 mm) from the fluorescence image and enhance the edges using the Laplacian operator and morphological closing operation; Superimposed on a white light image to form an augmented reality (AR) view, with a blood vessel contour accuracy of ±0.1mm; Adaptive noise reduction: Noise Model: A hybrid noise model (Gaussian + Poisson) is established to address the characteristics of endoscopic images (uneven illumination, motion artifacts). Based on wavelet transform and BM3D algorithm, the signal-to-noise ratio (SNR) is improved by ≥15dB.

[0027] According to the above technical solution, a control method for a double-bend flexible endoscope system for gastrointestinal examination is characterized in that the master-slave control system achieves precise control of the double-bend flexible endoscope through biomimetic design, multi-degree-of-freedom control and real-time force feedback mechanism, solving the control delay and positioning drift problems caused by the flexible deformation of traditional flexible endoscopes. The following are the core components and technical details of the system: System Architecture and Working Principle Master-slave control logic: Master (doctor's console): Receives operator commands (such as joystick movement, button triggering) and encodes them as digital signals; Slave end (flexible end effector): decodes signals and drives the end effector to bend, rinse, and image, while transmitting force and visual feedback back to the master end; closed-loop control cycle: ≤10ms, ensuring real-time operation (delay ≤30ms). Kinematic mapping: Establish the mapping relationship between the two-segment bending model of the mirror body and the controller joystick: Joystick X / Y axis → pitch / yaw of the proximal active segment; Knob angle → curvature adjustment of the distal passive segment; Foot pedal → flushing / sucking intensity; Main console design: Handheld controller: Three-axis force feedback joystick: Employs a magnetorheological damper (MRFluid), with an output force range of 0.1-5N and a resolution of 0.01N; joystick deflection angle ±30°, accuracy ±0.1°, and equipped with a thumb-touchscreen (3.5 inches) to display the mirror's posture in real time; Multi-function buttons: Mode switching button: white light / fluorescence imaging, continuous / pulse washing; Emergency return button: one-button straightening of the scope (response time ≤0.5 seconds); Visual feedback system: 3D stereoscopic display: 4K OLED screen (120Hz refresh rate), polarized light imaging technology, providing naked-eye 3D effect; integrated AR navigation: fluorescently visualized blood vessel outlines are superimposed on white light images, with adjustable transparency (10%-90%). Design of the actuator from the end: Robot drive unit: Multi-degree-of-freedom robotic arm: a six-axis collaborative robot (repeat positioning accuracy ±0.05mm), with a load capacity ≥5kg and an end effector with a flexible end effector interface; the kinematic model is based on DH parameters, and the inverse kinematics algorithm calculates joint angles in real time. SMA drive control module: High-frequency pulse power supply (frequency 1kHz, duty cycle adjustable), independently controls the heating power of 3 sets of SMA drive wires; temperature-resistance closed-loop feedback (PT100 sensor, accuracy ±0.1℃) to prevent overheating damage. Sensor fusion system: Pose sensor: Fiber Bragg grating array (FBG, 8 channels): embedded near the end of the mirror body, to monitor the bending angle in real time (accuracy ±0.5°). IMU (gyroscope + accelerometer): sampling rate 1kHz, detects the overall motion of the mirror body; Force and tactile sensor: Miniature MEMS six-dimensional force sensor (range ±10N, resolution 0.001N), integrated at the far end of the mirror body; triggers tactile alarm (vibration frequency 200Hz) when the contact force exceeds the limit (≥0.5N).

[0028] According to the above technical solution, the security protection mechanism includes: Over-limit emergency braking: When the bending angle is greater than 270° or the contact force is greater than 2N, the SMA drive power is cut off and the mirror body retraction is initiated (speed 10mm / s). Sterile barrier: Wireless communication (5GHz band, encrypted transmission) is used between the master and slave ends, and physical isolation is used to avoid contamination; Self-test and calibration: Automatically performs zero-position calibration of the mirror body (accuracy ±0.1°) and sensor calibration upon power-on.

[0029] Example 2: like Figure 1 As shown, the total length of the lens body is displayed (approximately 400mm), with the proximal active bending segment (150mm long) and the distal passive bending segment (100mm long) marked. Displays the main operating channel (inner diameter 3.2mm), flushing tube 7 and suction tube 8 (circular distribution), and external handle controller; Key components: shape memory alloy drive wire, superelastic nickel-titanium alloy skeleton 1, fiber optic image transmission bundle 5, and 4K CMOS sensor as imaging module 6.

[0030] Active bending section stainless steel textured tube 4; The surface of the super-elastic nickel-titanium alloy skeleton 1 is made of silicone 2, and the interior has diamond-shaped hollow units 3. like Figure 2 As shown, the cross-section of the proximal segment (6mm in diameter) reveals a three-layer structure: Inner layer: Polyimide-based tubing; Middle layer: Stainless steel woven mesh; Outer layer: silicone + antibacterial coating; Three SMA drive wires, evenly distributed at 120°, are SMA-19, SMA-210, and SMA-311; imaging module 11; flushing tube 7; and suction tube 8.

[0031] The top shows imaging module 6, labeled "4K CMOS".

[0032] Example 3: Manufacturing of double-curvature flexible lens body: Step 1: Preparation of the proximal active bending segment: 1. Driving wire assembly: Take 3 Ni-Ti-Cu shape memory alloy wires (0.15mm in diameter and 300mm in length), embed them into polyimide base tubes (6mm in inner diameter and 0.1mm in wall thickness) at 120° circumferential intervals, and fix them with epoxy resin; weld copper wires (0.1mm in diameter) to the ends of the driving wires and connect them to the temperature control circuit board.

[0033] 2. Mechanical reinforcement layer processing: 316L stainless steel mesh (0.05mm wire diameter, 80% coverage) is woven on the outer layer of the polyimide base tube, with a coverage length of 150mm; medical silicone (0.3mm thickness, Shore hardness 40A) is coated on the surface of the woven mesh using plasma spraying process.

[0034] 3. Antibacterial treatment: The outer layer of the microscope is impregnated with a silver-loaded nano-titanium dioxide solution (silver content 2wt%), dried and cured at 60℃ to form an antibacterial coating.

[0035] Step 2: Preparation of the distal passive bending segment: 1. Nickel-Ti alloy skeleton forming: Ni-Ti alloy tube (outer diameter 6mm, wall thickness 0.2mm) is laser-cut to cut diamond hollow patterns (unit size 1mm×0.5mm), with a hollowing rate of 65%; the skeleton is vacuum annealed at 500℃ for 30 minutes, and the superelastic recovery rate is ≥98%.

[0036] 2. Silicone Coating: The skeleton is placed into the injection mold, liquid silicone (Shore hardness 30A) is injected, and after curing, an outer layer is formed; the surface is laser-engraved with transverse ripples (depth 50μm, spacing 0.5mm).

[0037] Step 3: Two-segment connection and testing: 1. Proximal and distal docking: Medical-grade epoxy adhesive is used to bond the proximal active segment and the distal passive segment, with a titanium alloy collar (0.1mm wall thickness) nested at the connection point, with a tensile strength ≥200N; 2. Performance verification: Bending test: Drive the proximal segment to 180°, and the distal passive segment adaptively bends to 270°, with no plastic deformation after 10,000 cycles; Compression test: Apply 50 N / cm² pressure axially, and the lens deformation rate is ≤2%.

[0038] Example 4: Dual-modal imaging module implementation: Step 1: Optical component integration: 1. Sensor Packaging: The Sony IMX585 4K CMOS sensor and the InGaAs fluorescent sensor are fixed side by side on a ceramic substrate (10mm×8mm); a dichroic prism (reflection 830nm, transmission 400-700nm) is installed, and the optical path is adjusted so that white light and fluorescence are projected onto the corresponding sensors respectively.

[0039] 2. Lighting system installation: A ring-shaped white LED (CCT 5500K, 2W power) and a near-infrared laser diode (805nm, 50mW) are arranged around the sensor; light is guided to the front end of the mirror body through a flexible fiber bundle (1.5mm in diameter).

[0040] Step 2: AI Image Processing Deployment: 1. Algorithm Training: Train the U-Net model using 10,000 frames of gastrointestinal examination images. The input is 3 consecutive frames of images, and the output is a stable image after motion compensation. Loss function: mean squared error (MSE) + structural similarity (SSIM). Train until the accuracy on the validation set is ≥95%.

[0041] 2. Hardware Deployment: Deploy the optimized model on an FPGA (Xilinx Zynq UltraScale+) with an inference latency of ≤8ms; integrate it into the lens handle and connect it to the imaging module via a PCIe interface.

[0042] Step 3: Imaging performance verification 1. Resolution test: Using the ISO 12233 test card, the resolution in white light mode is ≥2000 LW / PH, and the resolution in fluorescence mode is ≥500 LW / PH; 2. Latency Test: The end-to-end latency measured with the high-speed camera (1000fps) is ≤30ms; 3. Fluorescence sensitivity: In vitro simulated vascular perfusion of 0.01μM ICG, fluorescence signal-to-noise ratio (SNR) ≥20dB.

[0043] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A double-curved flexible endoscope system for gastrointestinal examination, characterized in that: It includes a proximal active bending segment, a distal passive bending segment, and a modal imaging module; The system solves the contradiction between the blind spot problem of traditional rigid endoscopes in gastrointestinal examinations and the insufficient mechanical performance of flexible endoscopes by combining a "active and passive" dual-bending collaborative mechanism with high-resolution dual-modal imaging technology and mechanically reinforced structural design. The proximal active bending section is driven by a shape memory alloy to achieve precise multi-degree-of-freedom bending control; The distal passive bending section is a hyperelastic structure with adaptive properties, possessing high bending compliance and limiting protection functions. The modal imaging module integrates white light imaging and near-infrared fluorescence navigation functions, and combined with AI enhancement algorithms, it can achieve high-definition, low-latency image acquisition and augmented reality-assisted display in complex gastrointestinal environments.

2. The double-curved flexible endoscope system for gastrointestinal examination according to claim 1, characterized in that, The core material of the driving structure of the proximal active bending section is a shape memory alloy driving wire: a Ni-Ti-Cu ternary alloy with a diameter of 0.15 mm and a phase transformation temperature of 42℃. The drive wire layout consists of 3 drive wires evenly distributed in a 120° circumferential direction, with each wire spaced 2 mm apart and arranged in parallel, for a total length of 300 mm. The control mechanism adopts current drive. A current of 0.8-1.2A is applied to one or more drive wires through the PID temperature control circuit to trigger the martensite → austenite phase transformation. The shrinkage rate of the drive wire is 8.5%. The bending angle calculation formula is: θ=(ΔL / r)×(180 / π) Multi-degree-of-freedom bending: By combining the drive wires at different positions, single-plane bending can be achieved. Composite planar bending, with each set of drive filaments connected to an independent temperature control circuit at the end, triggers phase change through Joule heating, with a single filament shrinkage rate ≥8%, achieving ±180° active bending; The bending control logic is as follows: a. Single-sided drive wire heating: The mirror body bends in the corresponding direction; b. Dual-sided drive wire synergistic heating: achieving composite planar bending.

3. A double-curved flexible endoscope system for gastrointestinal examination according to claim 2, characterized in that, The mechanical reinforcement of the proximal active bending section adopts a multi-layer composite design: inner layer: polyimide-based tube, providing insulation and high temperature resistance; Middle layer: 316L stainless steel woven mesh, with compressive strength increased to 60N / cm² and torsional stiffness ≥0.15N·m / rad; Outer layer: Medical-grade silicone, coated with a silver-loaded nano-TiO2 coating, with an antibacterial rate of ≥99.9%; The middle layer is nested with stainless steel woven mesh to enhance torsional and compressive strength; The outer layer is covered with medical-grade silicone, and the surface is coated with a silver-loaded nano-titanium dioxide antibacterial coating to inhibit intraoperative infection.

4. A double-curved flexible endoscope system for gastrointestinal examination according to claim 1, characterized in that, The distal passive bending section is an adaptive skeleton, employing a superelastic nickel-titanium alloy skeleton: the Ni-Ti alloy tube is processed using laser cutting technology to form rhomboid hollow units with a hollowing rate of 65% and a maximum allowable bending radius of 5mm. After heat treatment, the hyperelastic strain recovery rate of the skeleton is ≥98%. Silicone coating: Double-layer injection molding: the inner layer is high-adhesion silicone, and the outer layer is wear-resistant silicone, with a total thickness of 0.5mm; Surface micro-texturing: laser engraving of transverse ripples.

5. A double-curved flexible endoscope system for gastrointestinal examination according to claim 4, characterized in that, The limiting protection mechanism of the distal passive bending section is a mechanical limiter: titanium alloy spring plates are embedded in the 5th, 10th and 15th hollow units of the skeleton. When the bending angle exceeds 270°, the spring plates contact the adjacent units to limit further bending. Limit trigger force ≥0.5N to avoid false triggering; Optical self-testing system: integrates a miniature fiber optic grating sensor to monitor bending strain in real time and trigger an audible and visual alarm when the limit is exceeded.

6. A double-curved flexible endoscope system for gastrointestinal examination according to claim 1, characterized in that, The modal imaging module integrates white light 4K imaging and near-infrared fluorescence navigation functions. Through intelligent switching and AI enhancement technology, the following is a detailed technical breakdown of the module: Optical system hardware design: Dual sensor side-by-side layout: 4K CMOS sensor: Model: Sony IMX585, 1 / 1.8-inch back-illuminated sensor, effective pixels 3840×2160, pixel size 1.4μm; Dynamic range: 85dB, supports 60fps full resolution output; Spectral response: 400-700nm, equipped with a sapphire protective window; Near-infrared fluorescence sensor: InGaAs focal plane array, response band 800-1700nm; Integrated narrowband filter to suppress background noise; Spectroscopic prism system: adopts dichroic prism, with a reflection band of 800-850nm and a transmission band of 400-700nm; After the white light and fluorescent light paths are separated, they are projected onto the CMOS and InGaAs sensors respectively to achieve dual-channel synchronous acquisition; Lighting system: White light illumination: High color rendering LED array, power 2W, light is guided to the front end through a flexible optical fiber bundle; Ring-shaped layout, uniformity ≥90%; Fluorescent excitation source: near-infrared laser diode, modulation frequency 1kHz, to avoid tissue thermal damage; When matched with ICG developer, the excitation efficiency is ≥85%; Fiber optic image bundle: Structural parameters: The flexible fiber bundle has a diameter of 2mm, the single filament has a diameter of 10μm, and the arrangement is hexagonal close packing; Numerical aperture NA=0.4, transmittance ≥70%; Bending-resistant design: The outer layer of the fiber bundle is coated with an elastic polyurethane sheath, with a minimum bending radius of 3mm and a transmission loss of ≤3dB.

7. A double-curved flexible endoscope system for gastrointestinal examination according to claim 6, characterized in that, The imaging mode switching and control of the modal imaging module adopts a dual-modal workflow: White light mode: By default, the white light LED is turned on, and the CMOS sensor acquires visible light images for anatomical structure observation; Resolution: 3840×2160@60fps, latency ≤30ms; Fluorescence mode: After ICG injection, a near-infrared laser is activated, and the InGaAs sensor captures the fluorescence signal; Real-time display of blood flow in blood vessels, with a switching time of ≤100ms; Intelligent switching logic: Manual switching: The operator can switch modes instantly via the handle buttons; Automatic trigger: When the AI ​​algorithm detects bleeding or the need for vascular visualization, the fluorescence mode is automatically activated.

8. A double-curved flexible endoscope system for gastrointestinal examination according to claim 6, characterized in that, The AI ​​image enhancement and processing employs motion blur compensation: Algorithm architecture: Based on U-Net convolutional neural network, the input is 3 consecutive frames of images, and the output is a motion vector field; Dynamically corrects pixel displacement caused by gastrointestinal peristalsis, with a compensation accuracy of ±0.5 pixels; Real-time performance: Deployed on FPGA, processing latency ≤8ms; Supports real-time processing at 1080p@120fps; Enhanced vascular margins: Multi-scale feature fusion: extract the vascular skeleton from the fluorescence image and enhance the edges through the Laplacian operator and morphological closing operation; Superimposed on a white light image to form an augmented reality view, with a blood vessel contour accuracy of ±0.1mm; Adaptive noise reduction: Noise Model: A hybrid noise model is established based on the characteristics of endoscopic images; Based on wavelet transform and BM3D algorithm, the signal-to-noise ratio is improved by ≥15dB.

9. The control method for a double-curved flexible endoscope system for gastrointestinal examination according to claim 1, characterized in that, The master-slave control system achieves precise control of the double-bend flexible lens through biomimetic design, multi-degree-of-freedom control and real-time force feedback mechanism, solving the control delay and positioning drift problems caused by the flexible deformation of traditional flexible lenses. The following are the core components and technical details of the system: System architecture and working principle: Master-slave control logic: Master end: Receives the operator's operation instructions and encodes them as digital signals; Slave end: decodes signals and drives the mirror body to bend, rinse, and image, while transmitting force and visual feedback back to the master end; closed-loop control cycle: ≤10ms; Kinematic mapping: Establish the mapping relationship between the mirror body's two-segment bending model and the controller's joystick: joystick X / Y axis, pitch / yaw of the proximal active segment; Knob angle and remote passive section curvature adjustment; foot pedal and flushing / sucking intensity; Main console design: Handheld controller: Three-axis force feedback joystick: adopts magnetorheological damper, output force range 0.1-5N, resolution 0.01N; joystick deflection angle ±30°, accuracy ±0.1°, equipped with thumb touch screen to display the mirror body posture in real time; Multi-function buttons: Mode switching button: white light / fluorescence imaging, continuous / pulse washing; Emergency return button: one-button straightening of the scope; Visual feedback system: 3D stereoscopic display: 4K OLED screen, polarized light imaging technology, providing naked-eye 3D effect; integrated AR navigation: fluorescently visualized blood vessel outlines are superimposed on white light images, with adjustable transparency; Design of the actuator from the end: Robot drive unit: Multi-degree-of-freedom robotic arm: a six-axis collaborative robot with a load capacity of ≥5kg and an end effector with a flexible end effector interface; the kinematic model is based on DH parameters, and the inverse kinematics algorithm calculates joint angles in real time. SMA drive control module: high-frequency pulse power supply, independently controls the heating power of 3 sets of SMA drive wires; temperature-resistance closed-loop feedback to prevent overheating damage; Sensor fusion system: Pose sensor: Fiber grating array: embedded near the mirror body to monitor bending angle in real time; IMU: Sampling rate 1kHz, detects overall movement of the mirror body; Force tactile sensor: a miniature MEMS six-dimensional force sensor integrated at the distal end of the mirror body; A tactile alarm is triggered when the contact force exceeds the limit.

10. A control method for a double-curved flexible endoscope system for gastrointestinal examination according to claim 9, characterized in that, Security protection mechanisms include: Over-limit emergency braking: When the bending angle is greater than 270° or the contact force is greater than 2N, the SMA drive power is cut off and the mirror body retraction is initiated; Sterile barrier: Wireless communication is used between the master and slave ends, and physical isolation is used to avoid contamination; Self-test and calibration: Automatically performs zero-position calibration of the mirror body and sensor calibration upon power-on.

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