Adaptive robot-assisted system and method for evaluating the position of trocars in robot-assisted laparoscopic surgical procedures
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- ROB SURGICAL SYST SL
- Filing Date
- 2026-05-07
- Publication Date
- 2026-08-06
Smart Images
Figure 2026127628000001_ABST
Abstract
Description
[Technical Field]
[0001] This invention generally relates to the field of laparoscopic surgery. In particular, this invention relates to an adaptive robot-assisted system for evaluating the position of a trocar in robot-assisted laparoscopic surgical procedures (or surgical interventions). This invention also provides a method for such purposes.
[0002] The proposed system and method allow for the continuous evaluation of the position of each trocar during the procedure, and thus make it possible to know the position of the fulcrum, i.e., the insertion point of each trocar in the patient's abdominal wall. The present invention also makes it possible to stabilize surgical instruments of a surgical robot (or operating robot) when movement (or displacement) occurs within the abdominal vault without the need to mechanically fix the trocars. [Background technology]
[0003] The use of robot-assisted laparoscopic surgery began in the late 1980s and involves performing surgical procedures remotely using a remote control station connected to a surgical robot.
[0004] One of the main problems that this type of application needs to address is translating the command station's movement [→M] into the robotic arm's movement [→R] so that the movement of the surgical instrument introduced into the abdominal cavity via the trocar follows the same movement [→P] as the command station's movement [→M] (see Figure 1).
[0005] To prevent instability of surgical instruments, the trocar is fixed on a suitable pivot point in space. Nevertheless, if the trocar is freely inserted into the abdominal vault, for example, if the trocar changes position in space due to the patient's breathing, undesirable movement occurs, and the robotic arm driving the surgical instrument generates a given applied torque in this case, accompanied by the raising of the abdominal vault.
[0006] Because the pivot point remains constant throughout the entire movement, most current systems use a multi-joint robotic arm to fix the trocar in space, and an architecture that allows programming of the movement of various joints prevents undesirable movement of the trocar, ensuring a remote fixed point for the passage of the surgical instrument shaft in all movements that enable an accessible 3D working volume (remote center of motion, RCM). Thus, the position of the surgical instrument in the abdominal cavity no longer depends on the possible movement of the trocar. Nevertheless, the force applied to the trocar by the robotic arm to prevent that movement can, in some cases, cause hematomas in the patient, as reflected in medical literature.
[0007] Reference [1] describes the architectural characteristics of a preceding strategy. In this architecture, the axis of rotation is aligned with the RCM point, so that two rotations J4 and J5, which allow the surgical instrument to rotate around the RCM point, mechanically ensure isocentric passage of the surgical instrument.
[0008] Reference [2] describes a similar solution to the one mentioned above, but it is more recent. This reference proposes a small table-mounted MIS robot that combines the high efficiency of conventional MIS technology with the dexterity of robotic operation. The master and slave manipulators of the new robot are integrated, allowing the surgeon to operate the robot next to the operating table. To reduce the difficulties of surgery, particularly suturing, surgical instruments are developed using a "roll-pitch-distal roll" wrist (or wrist) and rapid exchange interface. Similarly, to overcome uncoordinated hand-eye movements caused by the fulcrum effect, a motion mapping model is established for the robot.
[0009] To avoid the typical side effects of robot-assisted laparoscopic surgery resulting from stress caused by the trocar on the patient, the introduction of passive, articulated, and sensory (or sensorized) arms that allow for the continuous calculation of the actual position of the trocar in 3D space has also been proposed (Reference [3]). Thus, this system makes it possible to ensure that the surgical robot does not apply any force to the trocar, and therefore the development of hematomas in the patient is prevented. In contrast, the length of penetration (or insertion) of the trocar is not defined, which prevents the calculation of the position of surgical instruments within the abdominal cavity.
[0010] In reference [4], a system for performing minimally invasive cardiac procedures is also disclosed. The system includes a pair of surgical instruments coupled to a pair of robotic arms. The instruments have end effectors that can be manipulated to hold and suture tissue. The robotic arms are coupled by a controller to a pair of master handles. The handles can be moved by the surgeon to generate corresponding movements of the end effectors. The movement of the handles is scaled so that the corresponding movement of the end effectors is typically smaller than the movement performed by the surgeon's hand. The scale factor is adjustable so that the surgeon can control the resolution of the end effector's movement. The movement of the end effectors can be controlled by input buttons, so that the end effectors move only when the buttons are pressed by the surgeon. The input buttons allow the surgeon to adjust the position of the handles without moving the end effectors, so that the handles can be moved to a more comfortable (or easily maneuverable) position. The system may also have a robot-controlled endoscope that allows the surgeon to remotely view the surgical site. The cardiac procedure may be performed by making a small incision in the patient's skin and inserting the instruments and endoscope into the patient. The surgeon operates the handle and moves the end effector to perform cardiac procedures such as coronary artery bypass grafting.
[0011] Therefore, a new system and method are needed that enables continuous evaluation of the trocar's position when the robot arm's joints are passive joints.
[0012] References: [1] da Vinci® System: Technology and Surgical Analysis, https: / / entokey.com / the-da-vinci-system-technology-and-surgical-analysis / . [2] Huaifeng Zhang et al., System design of a new MIS robot combining the advantages of MIS technology and robotic technology. Digital object identifier 10.1109 / ACCESS.2020. [3] Design and evaluation of a slave manipulator with a roll-pitch-roll wrist, Autotool loading mechanism in telerobot surgery, Ki-Young Kim et al. International Journal of Medical Robotics and Computer-Assisted Surgery. [4]US5855583A. Wang Yulun et al. “Method and apparatus for performing minimally invasive cardiac procedures”. [Overview of the project] [Means for solving the problem]
[0013] To this end, embodiments of the present invention, according to a first aspect, provide an adaptable robot-assisted system for evaluating the position of a trocar during robot-assisted laparoscopic surgical procedures. The proposed system comprises a surgical robot having one or more robotic arms articulated with several degrees of freedom. Each robotic arm is positioned / configured to secure a surgical instrument via a passive joint. Each of the passive joints is configured to rotate freely around a single intersection of the axis of rotation.
[0014] Similarly, each surgical instrument is positioned / suited to be coupled to a trocar that can be introduced into the patient's abdominal cavity during laparoscopic surgical procedures. The robot-assisted system further includes a control unit configured to control the movement within the robotic arms described above, a command station configured for the assistance / remote control of the surgical robot via control elements, and sensors positioned within each robotic arm and configured to measure the angles α and β of the direction (or orientation) of the rotation axis of the passive joints. The control unit is operably connected to the command station.
[0015] In the proposed system, the control unit performs a comparison of the directional angles α and β measured by sensors with the corresponding theoretical directional angles α and β when there is no trocar movement, for each movement of an intraperitoneal surgical instrument established during a specific time interval in the procedure, and performs a correction of the parameter ρ, by increasing the parameter ρ positively or negatively for each movement during the specific time interval according to the sign value of the error obtained in the comparison, thereby performing a correction of the parameter ρ relative to (i.e., corresponding to) the distance between the intersection of the rotation axes of the passive joint and the corresponding pivot point, thereby performing a dynamic estimation of the position of one or more trocars inserted into the wall of the abdominal cavity.
[0016] In one embodiment, the correction includes applying a fuzzy logic algorithm.
[0017] In particular, fuzzy logic algorithms are executed at a rate of approximately 200 to 1000 times per second. Therefore, since a large number of decisions (positive or negative errors) must be made in each movement, the control unit statistically averages the results obtained.
[0018] The control unit may be located inside the surgical robot. Alternatively, the control unit may be remote / external to the surgical robot and command station, and may be connected to them by wired or wireless connections.
[0019] Embodiments of the present invention also provide, according to another aspect, an adaptive method for evaluating the position of trocars in robotic-assisted laparoscopic surgery. The method includes performing a dynamic estimation of the position of a trocar inserted into a patient's abdominal cavity using a control unit that controls the movement of one or more robotic arms of a surgical robot. The trocar described above supports a surgical instrument fixed to one of the robotic arms.
[0020] To perform the dynamic estimation, the method includes, for each movement of a surgical instrument within the abdominal cavity established during a specific time interval during laparoscopic surgery, comparing the angles α and β in the direction of the axes of rotation of the passive joints of the robotic arm, measured previously, with the corresponding theoretical direction angles α and β when there is no movement of the trocar. Similarly, the method includes performing a correction of a parameter ρ corresponding to the distance between the intersection of the axes of rotation of the passive joints and the fulcrum, by increasing the parameter ρ positively or negatively for each of the movements during the above-mentioned specific time interval, according to the sign value of the error obtained in a statistically filtered comparison.
[0021] In some embodiments, the measured and theoretical direction angles α and β are stored in a memory or database.
[0022] In some embodiments, the method is performed for each trocar used during the procedure. Each trocar supports a surgical instrument fixed to a robotic arm of a surgical robot. Generally, each surgical robot includes from one to four robotic arms.
[0023] Other embodiments of the invention disclosed herein may also include a computer program product for performing the steps and operations executed by the above-described control unit. More specifically, embodiments include a computer system-readable medium including encoded code instructions therein, which, when executed on at least one processor of the computer system, cause the processor to perform the operations shown herein as embodiments of the invention.
[0024] The present invention thus enables the position of the trocar / plural trocars in space to be estimated by a recursive calculation taking into account the numerical values of the angles of the directions of the instruments of the passive orientation joint described above.
Brief Description of the Drawings
[0025] The foregoing and other features and advantages will be better understood based on the following detailed description of some merely illustrative and non-limiting embodiments, with reference to the accompanying drawings. [Figure 1] FIG. 1 shows the architecture of the proposed system according to an embodiment of the present invention. [Figure 2] FIG. 2 shows the architecture of the proposed system according to an embodiment of the present invention. [Figure 3] FIG. 3 shows in more detail the different joints of two robot arms of a surgical robot. [Figure 4] FIG. 4 illustrates the angles α and β in the direction of the rotation axes of the passive joint and the parameter ρ with respect to the distance between the intersection of the rotation axes of the passive joint and the fulcrum. [Figure 5] FIG. 5 shows an example of the movement of a trocar in the abdominal cavity. [Figure 6] FIG. 6 schematically shows how the angles α and β and the parameter ρ in the directions of two robot arms of a surgical robot are obtained according to an embodiment.
Modes for Carrying Out the Invention
[0026] The present invention provides an adaptive robot-assisted system and adaptation method for evaluating the position of a trocar in robot-assisted laparoscopic surgical procedures, particularly for minimally invasive surgery.
[0027] The robot support system 1 proposed by the present invention enables a floating trocar, the trocar creates a joint that rotates the passive joint, and the trocar itself plays a role in fixing the direction of the robot support system without introducing any resistive torque.
[0028] Referring to Figure 2, one embodiment of the proposed robot-assisted system 1 is shown. In this embodiment, system 1 comprises a surgical robot 100 having four robotic arms 101, each holding and manipulating a surgical instrument 102 that rotates through a trocar 103. The operator controls the robot from a command station 110 via a control device 111 and / or pedals 113 while viewing a scene via a screen 112. Similarly, the system includes a control unit (not shown) that calculates the movement of the joints of the robotic arms 101, so that the fixed points 105 supporting the surgical instruments 102 perform several trajectories, and consequently, the trajectories performed by the distal elements 104 of the surgical instruments 102 rotating through the trocar 103 correspond to the movements performed by the operator via the control device 111 and / or pedals 113.
[0029] The control unit may include processing units formed by one or more processors and peripheral devices, such as an arithmetic logic unit, a communication bus, input / output elements, etc.
[0030] Figure 3 shows in more detail the architecture of the robotic arm 101 formed by a multi-joint chain. In particular, Figure 3 shows two configurations of the robotic arm 101 of the surgical robot 100 (the other two arms are not shown for simplification of the figure). One robotic arm 101 is formed by joints 201 (referring to angles W0B, W1B, W2B and W3B) and 202 (referring to angles W4B and W5B), while the other arm is formed by joints 301 (referring to angles W0c, W2c and W3c) and 302 (referring to angles W4c and W5c), assuming that the robotic arms 101 may have various architectures / designs for fixing their movement in space. Similarly, since the robotic arms 101 have different architectures, interference between them is minimized. Properly motorized joints 201 and 301 enable the movement of the support for the surgical instrument 102 in 3D space.
[0031] Joints 202 and 302 are passive, particularly Cardan-type joints. Therefore, since the parameter ρ (see Figure 4) is not defined, the position of the trocar 103 is not determined, which prevents the calculation of the position of the intraperitoneal surgical instrument 102. The calculation of parameter ρ can be performed geometrically from different positions of the robot arm 101, taking into account that the directional angles α and β from different points converge to a fixed point of the trocar 103 (see Figure 5). In practice, these theoretical solutions have not been able to provide sufficiently accurate results, given that the data (i.e., changes in directional angles α and β) are very small and the resolution of the angle sensors used to measure the angles is limited. To obtain more accurate results, the present invention performs iterative calculations by the control unit described above to perform the estimation and correction (or correction) of the parameter ρ described above. To this end, based on the initial position ρ0, for each position of the robot arm 101 movement over a specific time interval, a positive or negative correction of this magnitude is performed for each movement according to the sign of the error observed in the comparison of directional angles α and β. When corrections are performed rapidly and many times per second, the incremental values of the parameter ρ are statistically filtered / estimated.
[0032] If the estimation of ρ is correct, the line in space defined from the center of rotation of the direction in space, defined by the directional angles α and β obtained by sensors placed on each robot arm 101, will pass through the pivot point. A negative estimation error of distance ρ will result in smaller-than-expected variations in angles α and β, while a positive estimation error will result in larger-than-expected variations in angles α and β. The system can thereby perform kinematic calculations to control the position of the intraperitoneal surgical instrument 102 by continuously updating the estimation of the pivot point position of the trocar 103 and ensuring (or ensuring / ensuring) that the stress on the robot arm 101 on the trocar 103 is zero, since the passive orientation joints 202, 302 are passive joints.
[0033] In certain embodiments, the corrections mentioned are not performed in numerical algebraic form, nor are they performed using numerical values of the directional angles α and β, but rather by a fuzzy logic algorithm that considers the positive or negative deviation between the values of these two angular directions measured after each traveled interval and the direction that the trocar 103 would have had if there had been no movement.
[0034] In one embodiment, the parameter ρ is estimated based on changes in angles α and β when the elevation motion of the trocar 103 is caused, for example, by a change in gas pressure, and when no motion (or movement) occurs at all via the control device 111 of the command station 110.
[0035] An embodiment of the algorithm for calculating the dynamic correction of the parameter ρ when one of the surgical arms 101 moves from a first point (1) to a second point (2) is described in detail below (see Figure 6).
[0036] According to this embodiment, the initial starting condition of the algorithm is the coordinate X of the trocar 103 calculated in the first penetration by the following equation. T ,Y T ,Z T That is the case.
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[0037] The preceding initial conditions are manipulated recursively at each new interval of motion. At position (1) of the robot arm 101, the coordinates (X) of the preceding trocar 103 are set. T1 ,Y T1 ,Z T1 ), and the preceding value ρ(t-1) of the parameter ρ are available.
[0038] Next, if the estimated value ρ(t-1) is correct and the trocar 103 remains in that position, the distance between the first and second points is calculated, and then the angles α and β of the direction it should have when reaching the second point are calculated.
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[0039] Next, the theoretical distance ρ(t) from the position of the robotic arm 101 at the second point to the trocar is calculated.
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[0040] At this second point, the new theoretical position of the trocar 103 as seen from the second point is calculated from the newly calculated distance ρ2.
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[0041] Finally, the iterative correction of the obtained value ρ2 is performed by applying fuzzy logic criteria based on the error between the previously calculated values of the angles αc2 and βc2 and the angles α m and β m measured actually by the sensor, based on the sign of the obtained error and on an estimate of how large or small said error is. ,Y R ,Z R ) are the coordinates of fixed point 105 (see Figure 4), and α and β are the trocar position (X T ,Y T ,Z T This is the angle (i.e., angle value) of the direction of the passive orientation joints 202 and 302 when they are updated.
[0044] The proposed invention may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functionality may be stored or coded as one or more instructions or codes in a computer-readable medium.
[0045] The scope of the present invention is defined in the appended claims. [→M], [→R], [→P], etc. indicate a sign with a vector. For example, [→M] means
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Claims
1. A surgical robot (100) comprising at least one robotic arm (101), wherein the robotic arm (101) includes a series of joints, and the series of joints are configured to secure a surgical instrument (102) by passive joints (202, 302), each of the passive joints (202, 302) is configured to rotate freely around an intersection common to several axes of rotation, and the surgical instrument (102) is adapted to be connected to a trocar (103), the trocar (103) being adapted for its introduction into the patient's abdominal cavity during laparoscopic surgical procedures, the surgical robot (100), A control unit configured to control movement within at least one robotic arm (101), A command station (110) configured for remote control of a surgical robot (100) via control elements (111, 113), wherein the control unit is operably connected to the command station (110), A sensor positioned within the robot arm (101) and configured to measure the angles α and β in the direction of the rotation axis of the passive joint (202, 302). The control unit includes - For each of the movements of the surgical instrument (102) within the abdominal cavity established during a specific time interval during the procedure, the steps include comparing the angle α and β of the direction measured by the sensor with the theoretical angle α and β of the direction corresponding when there is no movement of the trocar (103), - A step of performing a correction of parameter ρ, wherein the parameter ρ corresponding to the distance between the intersection of the rotation axes of the passive joint (202, 302) and the pivot point is increased positively or negatively in each of the movements during the specific time interval according to the sign value of the error obtained in the comparison. The system is further configured to perform dynamic estimation of the position of the trocar (103) inserted into the wall of the abdominal cavity by performing the following: An adaptive robot-assisted system for evaluating the position of the trocar during robot-assisted laparoscopic surgical procedures.
2. The system according to claim 1, wherein the correction includes applying a fuzzy logic algorithm.
3. The system according to claim 1, wherein the control element includes a pedal (113) and / or an actuator / push button (111).
4. The control unit is located inside the surgical robot (100) in the system according to any one of claims 1 to 3.
5. The apparatus according to any one of claims 1 to 3, wherein the control unit is a remote control unit for the surgical robot (100) and the command station (110), and is connected to them by wired or wireless connection.
6. The step of performing a dynamic estimation of the position of at least one trocar (103) inserted into the abdominal wall of a patient, using a control unit that controls the movement of one or more robotic arms (101) of a surgical robot (100), wherein the trocar (103) is supported by a surgical instrument (102) fixed to one of the robotic arms (101) of the one or more robotic arms (101), The aforementioned step is, - A step of comparing, for each of the movements of the intraperitoneal surgical instrument (102) established during a specific time interval in a laparoscopic surgical procedure, angles α and β of the rotation axis direction of the passive joint (202, 302) of the robot arm (101), which have been previously measured, with the corresponding theoretical angles α and β when there is no movement of the trocar (103), wherein the measured angles α and β and the theoretical angles α and β are stored in memory or a database, - A step of performing a correction of parameter ρ, wherein the parameter ρ corresponding to the distance between the intersection of the rotation axes of the passive joint (202, 302) and the pivot point is increased positively or negatively in each of the movements during the specific time interval according to the sign value of the error obtained in the comparison. An adaptive method for evaluating the position of the trocar in robot-assisted laparoscopic surgical procedures, performed by executing [a specific procedure].
7. The method according to claim 6, wherein the correction includes applying a fuzzy logic algorithm.