CN-121971173-A - Flexible joint-based laparoscopic terminal pointing stabilization system and method

CN121971173ACN 121971173 ACN121971173 ACN 121971173ACN-121971173-A

Abstract

The invention relates to the technical field of medical equipment, in particular to a laparoscope tail end pointing stabilization system and method based on a flexible joint, which are used for constructing a closed-loop control framework integrating disturbance prediction, human-computer intention conflict identification and self-adaptive compensation gain adjustment, wherein tissue displacement is predicted in real time through pneumoperitoneum pressure, and a basic compensation instruction is generated; comparing the included angle between the main hand operation vector and the compensation vector and the operation force in a Cartesian space, dynamically judging conflict, rapidly attenuating the compensation gain and delivering control rights to doctors once the conflict is detected, adaptively adjusting the default gain according to historical conflict events, and step-like improving the compensation strength to optimize the stability and supporting personalized conflict tolerance configuration when no conflict exists. The invention solves or at least reduces the problem that the micro-displacement interference of the laparoscopic end caused by pneumoperitoneum pressure fluctuation conflicts with the operation intention of doctors, and provides a laparoscopic end pointing stabilizing system and method based on flexible joints.

Inventors

ZHANG CHUNXU
WU ZUYIN
ZHANG JIXIN
HUANG JING

Assignees

中国人民解放军联勤保障部队第九八八医院

Dates

Publication Date: 20260505
Application Date: 20260116

Claims (10)

1. A laparoscopic tip stabilization method based on a flexible joint, comprising the steps of: initializing a pneumoperitoneum compensation channel and a conflict monitoring module, predicting tissue displacement based on a pneumoperitoneum pressure signal, and generating an initial low-gain compensation instruction; The compensation instruction is overlapped to a main manipulator instruction, and the flexible joint is driven to perform fine adjustment; Calculating an included angle between a main manipulator instruction vector and a compensation instruction vector in a Cartesian space, and judging that man-machine intention conflict exists when the included angle is larger than a preset angle threshold value and the operating force or acceleration applied by a main hand exceeds a corresponding preset mechanical threshold value; Responding to the man-machine intention conflict, attenuating the compensation gain to zero in a preset time, and recording conflict event information; dynamically adjusting the follow-up default starting gain according to the accumulated conflict times or the number of continuous conflict-free disturbance events in a single operation; Under the conflict-free state, after the end of the preset observation window, the compensation gain is gradually increased in a stepwise manner, conflict detection is re-executed after each increase, and if the conflict is triggered, the system is retracted to the previous safety gain level and locked.
2. The method of claim 1, wherein if the collision event in the same operation is accumulated for more than a predetermined number of times, the default starting gain of the subsequent pneumoperitoneum compensation is reduced, and if the collision is not triggered by the continuous multiple disturbance events, the default starting gain is increased.
3. The laparoscopic tip stabilization method according to claim 1, wherein after each gain boost, a sensitivity threshold of collision decisions is temporarily lowered to enhance detection of potential countermeasure signals.
4. The method of claim 1, wherein a multi-stage collision tolerance configuration is supported, including a high tolerance mode in which more stringent direction and mechanical conditions are satisfied at the same time to determine a collision, and a low tolerance mode in which only a direction angle exceeding a lower threshold is required to be considered as a collision.
5. The laparoscopic tip pointing stabilization method according to claim 4, wherein the collision tolerance mode is automatically switched according to a currently used instrument type or a main hand operation speed, and the low tolerance mode is automatically switched when it is recognized that a fine operation instrument or a main hand movement speed is lower than a preset speed threshold.
6. The laparoscopic end pointing stabilization method according to claim 1, wherein said conflicting event information includes a time stamp, a pneumoperitoneum pressure variation amount, a compensation direction, a main hand reverse operation amplitude and a conflicting duration time.
7. The laparoscopic end pointing stabilization method according to claim 1, characterized in that a human-computer collaborative quality report is generated post-operatively, said report containing the number of collisions, average compensation gain and physician corrected delay index for operational assessment or system parameter optimization.
8. A laparoscopic end pointing stabilization system implementing the method of any one of claims 1 to 7, comprising: The pneumoperitoneum pressure signal acquisition module is used for acquiring a pressure signal output by the pneumoperitoneum machine; The tissue displacement prediction model unit is used for converting the pressure signal into a tissue displacement predicted value; a flexible joint driving controller connected to the multi-degree-of-freedom flexible joint mechanism at the tail end of the laparoscope; The master-slave operation mapping engine is used for generating a synthesized target position of the master manipulator and the compensation instruction; The human-computer intention conflict detector is used for calculating an instruction vector included angle in real time and judging conflict by combining a mechanical signal; an adaptive gain adjuster for performing gain attenuation, boosting, rollback, and long-term adaptive adjustment; And the personalized configuration interface is used for setting the conflict tolerance level.
9. The laparoscopic tip pointing stabilization system of claim 8, wherein the flexible joint drive controller employs a closed loop control strategy to ensure accurate tracking and stability of tip trimming actions.
10. The laparoscopic tip pointing stabilization system according to claim 8, wherein the human-machine intent collision detector integrates a multi-modal fusion criterion, and introduces a main hand operation entropy, eye movement tracking data or electromyography signals as auxiliary inputs in addition to vector included angles and operation forces to perform collision probability estimation.

Description

Flexible joint-based laparoscopic terminal pointing stabilization system and method Technical Field The invention belongs to the technical field of medical equipment, and particularly relates to a laparoscope tail end pointing stabilization system and method based on a flexible joint. Background The minimally invasive surgical technical system pursues visual surgical operation without dead angle, delay and interference. The laparoscope system is used as an important visual carrier, and whether the terminal direction is stable or not is directly related to the definition of the operation field, the operation precision and the safety of the whole operation. High-level surgical techniques from conventional laparoscopes to single Kong Fuqiang mirrors, robotic laparoscopes, and the like present new challenges to the dynamic response performance of instruments and the coordinated human-machine coordination capability. Because continuous perfusion and intermittent leakage of carbon dioxide under pneumoperitoneum conditions can cause unsteady fluctuation of the intra-abdominal pressure under a steady-state working condition, the intra-abdominal pressure can periodically disturb abdominal wall and visceral tissues to cause low-frequency fluctuation movement, and the disturbance of the external working condition can be transmitted to a laparoscope rod body along a puncture sleeve to cause small directional displacement of the tail end of a lens, so that continuous observation capability and fine operation capability of doctors on tissue structures are affected. Thus, how to achieve stabilization of laparoscopic tip pointing under dynamic conditions, and how to achieve a coordinated match of system behavior and surgeon's surgical intent is an important challenge faced by modern intelligent surgical equipment. At present, the problem of laparoscopic stability is solved, and two main ideas exist. And one is a mechanically locked type fixation. As disclosed in publication No. CN112244753B, the laparoscopic lens fixing device forms a multi-degree-of-freedom adjusting and rigid locking mechanism through the lifting frame, the feeding adjusting mechanism and the electromagnetic adsorption component, and can effectively inhibit lens drift under the condition that the displacement is zero or approximately zero (i.e., static or quasi-static). The method is characterized in that an open loop control logic is essentially adopted, the compensation capability is limited to mechanical locking at a known position, real-time tissue displacement caused by pneumoperitoneum pressure change is not perceived and responded, when a doctor has active visual angle conversion requirement, electromagnetic locking needs to be released firstly, the flow is complex, the continuity of operation is interrupted, and the method is difficult to adapt to high interaction frequency requirement in a changeable abdominal environment. And secondly, a flexible instrument with reinforced structure. The three-rod linkage-based multi-degree-of-freedom laparoscopic surgical instrument disclosed in the publication No. CN113413195B gives higher flexibility and hand feeling stability to an operator through fine mechanical transmission, but the stability of the laparoscopic surgical instrument still depends on manual adjustment and structural rigid support of the operator, and the laparoscopic surgical instrument does not have the sensing and self-adaptive compensation capability on external disturbance. Even an automatic stabilizing module which can be accessed in later period can easily not distinguish the intentional operation of a doctor from disturbance induced displacement if the existing multi-feedforward control thought, namely feedforward compensation of fixed strength is triggered according to a preset threshold, and man-machine countermeasure occurs, when the doctor actively and slightly rotates a lens, the system misjudges as disturbance drift, applies reverse moment, causes operation delay and shake to be increased, and even induces non-target tissue traction or damage. The above-mentioned various prior arts cannot effectively solve the problem of stability of human-machine cooperative control, and the above-mentioned various technical solutions fundamentally lack correct understanding of the deep principle of human-machine control architecture, specifically, they all treat amplitude suppression and operation intention as independent or even antagonistic variables, and use fixed rules or open loop logic to simply process, so that it is not fully known that laparoscopic operation is actually a tightly strongly coupled human-machine co-fusion control process, and doctor's operation intention is not only displacement instruction, but also includes comprehensive judgment of current operation field state, task requirement and risk assessment, and the applied amplitude is not pure noise, and its amplitude, frequency and direction are closely related to operat