Endoluminal device system, control device and method of operating the control device

Abstract

This endoluminal device system (100) comprises: an elongated and flexible endoluminal device (1); a wire (12) disposed, in the endoluminal device (1), in the longitudinal direction of the endoluminal device (1); sensors (3) for detecting the tension in the wire (12); a drive device (2) capable of pulling the wire (12); and at least one processor (5a). The processor (5a) causes the drive device (2) to perform a relaxation operation of relaxing the wire (12), acquires the tension in the wire (12) during the relaxing operation detected by a sensor (3), and adjusts a control parameter for the endoluminal device (1) on the basis of the tension in the wire (12).

Description

[Technical field]

[0001] The present invention relates to an endluminal device system, a control device and a control Operation of the device This relates to a method. [Background technology]

[0002] Conventionally, endoluminal devices such as manipulators or endoscopes that are inserted into a lumen through the mouth or anus to perform observation or treatment within the lumen have been known (see, for example, Patent Documents 1 to 3). The endoluminal device has a long flexible section, a movable section connected to the tip of the flexible section, and a power transmission member such as a wire for driving the movable section. In such endoluminal devices, there is an inconvenience that the power transmission characteristics of the power transmission member change depending on the shape of the flexible section, which in turn changes the operating characteristics of the movable section. Patent Documents 1 to 3 propose means for solving this inconvenience.

[0003] Specifically, in Patent Documents 1 and 2, a sensor is used to detect the shape of a flexible part, and a movable part is controlled based on the detected shape. Patent Document 1 uses a magnetic sensor (UPD) placed outside the endoluminal device, while Patent Document 2 uses a shape sensor inserted inside the endoluminal device.

[0004] In Patent Document 3, the movable section is operated in advance in a plurality of operation patterns in various shape patterns of the flexible section, and the control parameters are set in association with tension information of the power transmission member at that time. The tension information is a time integral value of tension, a rate of change, or a predetermined threshold value. Then, the tension information is acquired in a calibration operation during surgery, and the control parameters are acquired based on the acquired tension information. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2015-154814 A [Patent Document 2] Patent No. 6701232 [Patent Document 3] Patent No. 6278747 Summary of the Invention [Problem to be solved by the invention]

[0006] In the case of Patent Document 1, an additional device including a UPD is required, making the entire system large-scale. In addition, since the UPD can detect the shape of the flexible part only within the sensing area, there is a limit to the length of the flexible part that can be applied. For example, in the case of a long flexible part that protrudes from the sensing area, the shape of the entire flexible part cannot be detected, and as a result, it is difficult to control the movable part with high accuracy. In the case of Patent Document 2, the shape sensor needs to be inserted into and removed from the flexible portion, and the system becomes larger by the stroke of the shape sensor. Also, it takes time to obtain shape data.

[0007] In the case of Patent Document 3, the shape of the flexible section corresponding to tension information and control parameters such as a time integral value, a rate of change, or a predetermined threshold value is not unique. Therefore, if the shape of the flexible section during surgery differs from a previously set shape pattern, it may not be possible to obtain appropriate control parameters based on tension information. In particular, when the shape of the flexible section has a high degree of freedom, such as when the external portion of the flexible section placed outside the body is long, it is difficult to determine appropriate control parameters based on the above tension information.

[0008] The present invention has been made in consideration of the above circumstances, and provides an endluminal device system, a control device, and a control method that can set appropriate control parameters according to the shape of a flexible portion with a simple configuration. Operation of the device The present invention aims to provide a method. [Means for solving the problem]

[0009] One aspect of the present invention is a method for manufacturing an endoluminal device, comprising: Flexible A first wire, a first sensor for detecting tension in the first wire, a drive device capable of pulling the first wire, and at least one processor; a second sensor for detecting a displacement of the first wire; Equipped with The above at least one processor causes the driver to perform a loosening operation to loosen the first wire being pulled, and obtains tension of the first wire during the loosening operation detected by the first sensor; obtaining a displacement of the first wire during the relaxation motion detected by the second sensor; During the relaxation operation Rate of change of the tension with respect to the displacement and adjusting a control parameter of the endoluminal device based on the.

[0010] Another aspect of the present invention is a control device for an endoluminal device system, the endoluminal device system comprising an elongated and flexible endoluminal device and a stent disposed in the endoluminal device in a longitudinal direction of the endoluminal device. Flexible A first wire, a first sensor that detects tension of the first wire, and a drive device that can pull the first wire; a second sensor for detecting a displacement of the first wire; and at least one processor, the at least one processor causing the driving device to perform a loosening operation to loosen the first wire being pulled, and acquiring a tension of the first wire during the loosening operation detected by the first sensor; obtaining a displacement of the first wire during the relaxation motion detected by the second sensor; During the relaxation operation Rate of change of the tension with respect to the displacement and a control device that adjusts a control parameter of the endoluminal device based on the control parameter.

[0011] Another aspect of the present invention is A method of operating a control device that controls an endoluminal device, the method comprising: a flexible first wire is arranged within the endoluminal device in a longitudinal direction of the endoluminal device; the control device performs a relaxation operation to relax the first wire that is being pulled; the control device acquires a tension of the first wire during the relaxation operation; the control device acquires a displacement of the first wire during the relaxation operation; and the control device adjusts a control parameter of the endoluminal device based on a rate of change of the tension with respect to the displacement during the relaxation operation. In addition, the reference example of the present invention isA control method for an endoluminal device, comprising: a first wire is arranged within the endoluminal device in the longitudinal direction of the endoluminal device; a relaxation operation is performed to relax the first wire that is being pulled; a tension in the first wire during the relaxation operation is obtained; and a control parameter of the endoluminal device is adjusted based on the tension during the relaxation operation. Effect of the Invention

[0012] According to the present invention, it is possible to set appropriate control parameters according to the shape of the flexible section with a simple configuration. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is an external view showing an overall configuration of an endoluminal device system according to a first embodiment. [Diagram 2] FIG. 1 is a schematic configuration diagram of an endoluminal device system according to a first embodiment. [Diagram 3] 4 is a flowchart of a control method according to the first embodiment. [Figure 4] FIG. 1 shows the shape of a wire having loops formed at the tip (top), central (middle) and base (bottom) ends. [Diagram 5] 5 is a graph showing the change in tension over time during a relaxation operation at the base and tip ends of the wires of each shape in FIG. 4. [Figure 6A] FIG. 13 is a diagram showing an example of the distribution of tension from the base end to the tip end of a wire. [Figure 6B] 13A and 13B are diagrams illustrating another example of the distribution of tension from the base end to the tip end of the wire. [Figure 7] FIG. 13 is a diagram showing an example of a wire shape. [Figure 8] 13 is a graph showing the relationship between wire displacement and tension during a relaxation operation. [Figure 9] 4 is a flowchart of a modified example of the control method of FIG. 3. [Figure 10] FIG. 3 is a schematic configuration diagram of another modified example of the endoluminal device system of FIG. 2. [Figure 11] 4 is a flowchart of another modified example of the control method of FIG. 3. [Figure 12] 11A and 11B are diagrams illustrating a method for estimating the shape of a flexible portion. [Figure 13] 13 is a flowchart showing a procedure for estimating the shape of a flexible portion. [Figure 14] FIG. 11 is a schematic configuration diagram of an endoluminal device system according to a second embodiment. [Figure 15] FIG. 11 is another schematic configuration diagram of the endoluminal device system according to the second embodiment. [Figure 16] FIG. 15 is a schematic configuration diagram of another modified example of the endoluminal device system of FIG. [Figure 17] 11 is a graph showing an example of spring characteristics of a measurement wire. [Figure 18] FIG. 11 is a schematic configuration diagram of an endoluminal device system according to a third embodiment. [Figure 19] FIG. 13 is a schematic diagram of an endoluminal device system according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] (First embodiment) An endluminal device system, a control device, and a control method according to a first embodiment of the present invention will be described with reference to the drawings. 1 shows an external view of a configuration example of an endoluminal device system 100 according to this embodiment. In the endoluminal device system 100, a control device 5 controls a drive device 2 based on an operation input to an operating device 6, whereby a movable part 11 of an endoluminal device 1 is electrically driven.

[0015] The endoluminal device 1 is a long and flexible device, for example an endoscope or a manipulator, that is inserted into a body cavity from an opening such as the mouth or anus to perform observation or treatment in the body cavity. Fig. 1 shows, as an example, a system 100 in which the endoluminal device 1 is an endoscope. Reference numeral 7 denotes an image processor that processes an endoscopic image acquired by the endoscope 1, and reference numeral 8 denotes a display device that displays the endoscopic image.

[0016] The drive unit 2 incorporating a motor and the like is placed beside the operating table 9 as an example. Therefore, the flexible part 13 of the electrically driven endoluminal device 1 has, in addition to the long internal part 13a inserted into the body, a long external part 13b arranged outside the body and connecting the base end of the internal part 13a to the drive unit 2. Such a flexible part 13 can take various curved shapes. In particular, the shape of the external part 13b is determined by the arrangement of the drive unit 2 and the operating table 9, so the range of change in shape is large. The power transmission characteristics of the wire 12 in the endoluminal device 1 change depending on the shape of the flexible part 13, and the responsiveness of the movable part 11 to the operation input to the operation device 6 may also change. As will be described later, the endoluminal device system 100 has a function of controlling the endoluminal device 1 so that the responsiveness of the movable part 11 is constant by controlling the drive unit 2 depending on the shape of the flexible part 13.

[0017] Fig. 2 shows a schematic configuration of an endoluminal device. As shown in Fig. 2, an endoluminal device system 100 includes an endoluminal device 1 having a movable part 11, one or more flexible wires (first wires) 12 provided in the endoluminal device 1, a driving device 2 that drives the movable part 11 by pulling and relaxing the wires 12, one or more tension sensors (first sensors) 3 that detect the tension of each wire 12, one or more displacement sensors (second sensors) 4 that detect the displacement of each wire 12, and a control device 5 that controls the driving device 2.

[0018] The endoluminal device 1 has a long and flexible soft portion 13. The base end of the soft portion 13 is connected to the driving device 2. The movable section 11 is connected to the tip of the flexible section 13. In this embodiment, the movable section 11 is a bending section that can be bent in a direction intersecting with the longitudinal direction of the flexible section 13.

[0019] The wires 12 have a function of transmitting the power given from the driving device 2 from the base end to the tip to operate the movable part 11, and also have a function of acquiring shape information of the flexible part 13. Hereinafter, the wires having the function of transmitting the power given from the driving device 2 from the base end to the tip to operate the movable part 11 will be referred to as driving wires, and the wires having the function of acquiring shape information of the flexible part 13 will be referred to as measurement wires. For example, four wires 12 are provided for bending the bending part 11 up, down, left, and right, respectively. In this embodiment, each of these four wires 12 has both a function as a driving wire and a function as a measurement wire.

[0020] The wire 12 is disposed within the flexible portion 13 along the longitudinal direction of the flexible portion 13, with the tip of the wire 12 fixed to the tip of the bending portion 11 and the base end of the wire 12 connected to the driving device 2. The flexible wire 12 thus extending over the entire length of the flexible portion 13 bends into the same shape as the flexible portion 13 as the flexible portion 13 bends.

[0021] The driving device 2 has one or more actuators 2a that drive the wire 12 by retracting and advancing the base end of the wire 12 in the longitudinal direction of the wire 12. The actuators 2a pull the wire 12 by retracting the base end of the wire 12, and relax the wire 12 by advancing the base end of the wire 12. The driving device 2 bends the bending section 11 by operating the actuators 2a in accordance with a control signal (described later) from the control device 5.

[0022] The tension sensor 3 is provided at the base end of the wire 12 and detects the tension at the base end of the wire 12 . The displacement sensor 4 detects the displacement of the base end of the wire 12 in the longitudinal direction of the wire 12. For example, the displacement sensor 4 is an angle sensor provided in the actuator 2a and detects the rotation angle of the motor of the actuator 2a as the displacement of the wire 12. The position of the base end of the wire 12 when the tension of the wire 12 is zero is the origin, and the displacement of the base end of the wire 12 detected by the displacement sensor 4 is the position of the base end of the wire 12 relative to the origin. Therefore, the displacement increases when the wire 12 is pulled and decreases when the wire 12 is relaxed.

[0023] The control device 5 includes at least one processor 5a, such as a central processing unit, and a memory unit 5b. The processor 5a receives an operation signal based on an input operation from the operation device 6, generates a control signal based on the operation signal, and transmits the control signal to the drive device 2. In this way, the processor 5a controls the drive device 2, and thereby controls the bending portion 11 of the endoluminal device 1.

[0024] The storage unit 5b includes a memory such as a RAM and a non-volatile recording medium such as a ROM or a HDD. The recording medium is a non-transitory computer-readable recording medium. The recording medium stores a control program for causing the processor 5a to execute a control method for controlling the endoluminal device 1 according to the shape of the flexible portion 13.

[0025] Next, a control method of the endluminal device 1 executed by the control device 5 will be described with reference to FIG. As shown in FIG. 3, the control method includes step S1 of receiving a trigger, step S2 of performing a relaxation operation to relax the pulled wire 12, step S3 of acquiring the tension and displacement of the wire 12 during the relaxation operation detected by sensors 3 and 4, step S4 of adjusting control parameters of the endoluminal device 1 based on the tension and displacement during the relaxation operation, and step S5 of restoring the wire 12 to an initial state.

[0026] The trigger is input to the control device 5 by the operator using, for example, an input device (not shown). The operator can input the trigger to the control device 5 at any timing when the operator wishes to adjust the control parameters. For example, after inserting the flexible portion 13 into the body cavity, the operator inputs the trigger immediately before a task such as a treatment that requires precise movement of the bending portion 11. In response to receiving the input trigger (YES in step S1), the processor 5a executes steps S2 to S5.

[0027] Before step S2, the wires 12 and the bending portion 11 are placed in a predetermined initial state. The initial state is, for example, a state in which a predetermined initial tension is applied to all the wires 12 and the bending portion 11 is placed in a straight line. In step S2, the processor 5a causes the driver 2 to execute a pulling operation to pull the wire 12, and subsequently causes the driver 2 to execute a loosening operation to loosen the pulled wire 12. The wire 12 to be pulled and loosened is any one wire 12.

[0028] In the traction operation, the processor 5a, for example, causes the driving device 2 to traction the wire 12 by a predetermined amount, bringing the wire 12 into a state in which a predetermined target tension is applied. The predetermined target tension is within a range that does not prevent the flexible portion 13 from bending along the shape of the body cavity, and therefore, after the traction operation, the wire 12 is in a relaxed state to an extent that allows the flexible portion 13 to bend along the shape of the body cavity.

[0029] During the relaxation operation, the displacement of the proximal end of the wire 12 decreases over time, and the tension of the proximal end of the wire 12 decreases over time (see, for example, FIG. 5.) During the relaxation operation, the changing tension and displacement of the wire 12 are continuously detected by the sensors 3 and 4, for example, at a predetermined sampling period.

[0030] Here, as the displacement of the base end of the wire 12 decreases, the area where the tension decreases spreads from the base end to the tip side of the wire 12. That is, during the relaxation operation, the tension change (decrease in tension) is transmitted sequentially from the base end to the tip end of the wire 12. The processor 5a causes the drive device 2 to execute the relaxation operation at least until the tension change is transmitted to the tip end of the wire 12.

[0031] For example, the processor 5a may sequentially obtain the current tension or displacement from the sensors 3 and 4 during the relaxation operation, determine that the entire relaxation of the wire 12 is complete based on the current tension or displacement, and end the relaxation operation when the relaxation is complete. When the current tension becomes equal to or less than a predetermined value, or when the current displacement becomes equal to or less than a predetermined value, it is determined that the relaxation is complete. A change point at which the rate of change in tension changes may appear when the tension change reaches the tip of the wire 12. The processor 5a may terminate the relaxation operation when a change point in tension is detected.

[0032] In step S3, the processor 5a stores in the memory unit 5b in chronological order the tension and displacement during the relaxation operation detected by the sensors 3 and 4. In this way, the processor 5a acquires data on each of the tension and displacement during the relaxation operation. Fig. 5 shows the change over time in tension at the distal and proximal ends of wire 12 during the relaxation operation in three shape patterns 1, 2, and 3 of flexible section 13 in which loops are formed at the distal end, central portion, and proximal end, respectively, as shown in Fig. 4. As shown in Fig. 5, the change in tension in periods I, II, and III until the tension change reaches the distal end of wire 12 differs depending on the shape of flexible section 13. In other words, the change in tension during the relaxation operation includes shape information of flexible section 13.

[0033] Next, in step S4, the processor 5a calculates the rate of change of tension with respect to the displacement during the relaxation operation using the tension and displacement data acquired in step S3, and adjusts the control parameters based on the rate of change. The rate of change of tension is the rate of change of tension at each displacement from the maximum tension at the start of the relaxation operation.

[0034] The control parameter is the amount of pulling and relaxing of the wire 12 for transmitting the tension change to the tip of the wire 12. More specifically, the control parameter is the amount of displacement of the base end of the wire 12 in periods I, II, and III shown in Fig. 5. In other words, the control parameter is the amount of displacement of the base end of the wire 12 that corresponds to the tension change ΔT at the base end required for transmitting the tension change to the tip of the wire 12, as shown in Fig. 6A.

[0035] 7 and 8 explain the relationship between the shape of the wire 12 and the displacement and tension of the wire 12 during the relaxation operation. Since the change in tension at the base end of the wire 12 is transmitted in sequence from the base end to the tip end of the wire 12, the change in tension at each displacement Δxi (i=1, 2, ...) of the base end of the wire 12 contains shape information of the corresponding portion Pi of the wire 12.

[0036] For example, when the displacement of the base end of wire 12 decreases by Δx1, the tension change is transmitted to portion P1 of wire 12. Therefore, the tension change at displacement Δx1 includes the shape information of portion P1. When the displacement of the base end of wire 12 further decreases by Δx2, the tension change is transmitted to portion P2 of wire 12. Therefore, the tension change at displacement Δx2 includes the shape information of portions P1 and P2. Therefore, starting from the base end side of the wire 12, the shape of the portion Pi can be estimated from the rate of change Ti / Tp of tension with respect to the displacement xi, and the control parameters corresponding to the overall shape of the flexible section 13 can be determined based on such rate of change Ti / Tp.

[0037] In order to accurately estimate the shape of the flexible portion 13 from the change in tension during the relaxation operation, it is preferable that the tension of the wire 12 arranged along the flexible portion 13 monotonically decreases or increases from the base end to the tip end as shown in Fig. 6A. Therefore, during the relaxation operation, the processor 5a continues to gradually decrease the tension at the base end by continuing to advance the base end of the wire 12 until the tension change is transmitted to the tip end. For example, if the relaxation of the wire 12 is terminated and the wire is pulled again before the tension change reaches the tip, the tension of the wire 12 will no longer decrease monotonically from the base end to the tip, as shown in Fig. 6B. In this case, the relationship between the displacement and tension when the maximum displacement is updated is extracted.

[0038] After the relaxation operation is completed, in step S5, the processor 5a causes the driving device 2 to execute an initialization operation for returning the tension of the wire 12 to the initial tension. As a result, the wire 12 and the bending portion 11 are returned to their initial states. After step S5, the processor 5a generates a control signal based on the operation signal from the operation device 6 and the control parameters adjusted in step S4, and transmits the control signal to the drive device 2. This makes it possible to control the bending portion 11 with good responsiveness, regardless of the shape of the flexible portion 13.

[0039] Thus, according to this embodiment, the change in tension of the wire 12 during the relaxation operation differs depending on the curved shape of the flexible section 13, and the shape of the flexible section 13 corresponding to the change in tension of the wire 12 is unique. Therefore, appropriate control parameters according to the shape of the flexible section 13 can be set based on the change in tension of the wire 12. Furthermore, a simple configuration using the wires 12 and the sensors 3 and 4 makes it possible to obtain necessary data and set control parameters.

[0040] In addition, the wire 12 has a function as a drive wire and a function as a measurement wire. This eliminates the need to mount a separate measurement wire for acquiring shape information, and eliminates the need to add new components for measurement to the flexible section 13. Therefore, the diameter of the flexible section 13 can be reduced. Moreover, the tension and displacement data may be acquired during the operation in which the flexible section 13 is inserted into the body cavity and the bent bending section 11 returns to a straight shape. In this case, no operation is required to acquire the data, and the data required for adjusting the control parameters can be acquired without increasing the effort of the operator.

[0041] Furthermore, by acquiring data and adjusting control parameters immediately before an operation that requires precise movement of the bending portion 11, it is possible to reliably set optimal control parameters according to the shape of the flexible portion 13 at that time, and the bending portion 11 can be moved accurately in accordance with the operations inputted into the operating device 6.

[0042] In this embodiment, the processor 5a may cause the drive device 2 to perform pulling and relaxing operations without movement of the bending portion 11 by selecting the wires 12 to be pulled and relaxed. 9, before performing the pulling and relaxing operations in step S2, the processor 5a recognizes, among the multiple wires 12, the wire 12 being pulled for bending the bending portion 11, based on an operation signal from the operation device 6 (step S6). The recognition of the wire 12 being driven may be performed, for example, based on a control signal transmitted from the control device 5 to the drive device 2 or on the tension detected by the tension sensor 3.

[0043] In step S2 of the first example of the control method in Fig. 9, the processor 5a selects the wire 12 being driven and another wire 12 opposing the wire 12 being driven. The opposing wire 12 is a wire 12 for bending the bending portion 11 in a direction opposite to the bending direction of the bending portion 11 by the wire 12 being driven. For example, when the wire 12 being driven is an upward bending wire, the opposing wire 12 is a downward bending wire.

[0044] Next, the processor 5a controls the driving device 2 to simultaneously pull and relax the two selected wires 12 in the pulling and relaxing operations. The relaxing operation at this time is performed until the tension of the wire 12 being driven returns to the tension before the pulling operation. The processor 5a obtains data on the tension and displacement of at least one of the two wires 12 during the relaxing operation, and adjusts the control parameters based on the obtained data. According to this configuration, the moment applied to the bending portion 11 is balanced during the traction and relaxation operations, so that the bending direction and bending angle of the bending portion 11 are kept constant. Therefore, tension and displacement data can be obtained without causing the bending portion 11 to move.

[0045] In the second example of the control method of FIG. 9, the processor 5a selects any one of the wires 12 other than the wire 12 being driven, that is, selects one from the wires 12 not being driven. For example, one is selected from the other wires 12 excluding the wire 12 being driven and the wire 12 opposing it. Specifically, if the wire 12 being driven is for bending upward or downward, the wire 12 for bending leftward or rightward is selected. If the wire 12 being driven is for bending leftward or rightward, the wire 12 for bending upward or downward is selected. The processor 5a then controls the driver 2 to pull and release the selected one of the wires 12 in a pulling and releasing operation. This configuration also allows tension and displacement data to be obtained without causing any movement of the bending portion 11 during traction and relaxation movements.

[0046] In this embodiment, the movable part 11 is a curved part, but the movable part 11 is not limited to this and may have other forms. For example, the movable part 11 may be a joint or an end effector having a function such as gripping. 10 shows an endoluminal device 1 equipped with an end effector as a movable part 11. In this example, the end effector 11 has a pair of jaws that open and close relative to each other, and the pair of jaws are opened and closed by driving a wire 12.

[0047] In the present embodiment, the processor 5a executes the control method in response to a trigger input by an operator. Alternatively, the processor 5a may execute the control method automatically. For example, the processor 5a may repeatedly execute steps S2 to S5 at a predetermined time interval, in which case the data acquisition and the control parameter adjustment are repeatedly and automatically executed without the need for an operator to input a trigger. For example, in the process of inserting the flexible section 13 into a body cavity, the shape of the flexible section 13 continues to change. In such a situation, good responsiveness of the movable section 11 can be maintained by successively updating the control parameters in response to the change in the shape of the flexible section 13.

[0048] 11, the processor 5a may estimate the shape of the flexible section 13 based on the tension and displacement data (step S7). In this case, in step S4, the processor 5a may adjust the control parameters based on the rate of change of tension as described above, or may adjust the control parameters based on the shape of the flexible section 13. 12 explains a method for estimating the shape of the flexible section 13 from the tension and displacement of the wire 12, and shows the distribution of tension from the base end to the tip end of the wire 12. By this method, shape information such as the bending radius, bending angle, and length along the main axis of the flexible section 13 can be calculated.

[0049] 12, the wire 12 is considered to be composed of n elements i (i=1, 2, ..., n) in order from the base end to the tip end. Element 1 includes the base end of the wire 12, and element n includes the tip end of the wire 12. In the initial state at t=t0, the tension of the wire 12 exponentially decreases from the base end to the tip end due to the effect of friction acting on the wire 12. As described above, in the process in which the wire 12 relaxes due to the displacement (advancement) of the base end of the wire 12, the change in tension (decrease in tension) is transmitted sequentially from the base end to the tip end.

[0050] At t=ti-1, the tension at the base end decreases from the initial maximum tension Tp to tension Tr_(i-1), and the tension change is transmitted to element i-1. That is, the tension decreases in the operating region [1:i-1], and the elongation of elements 1, 2, ..., i-1 within the operating region [1:i-1] changes (decreases). Similarly, at t=ti, the tension at the base end decreases from the maximum tension Tp to tension Tr_i, and the tension change is transmitted to element i.

[0051] Fig. 13 shows the procedure for calculating the shape of the wire 12 (i.e., the shape of the flexible portion 13). As shown in Fig. 13, steps S12 to S16 are repeated while incrementing i (steps S11, S17), to calculate the curvature angle θi, length Li and curvature radius Ri of element i, starting from the base end side. The calculated curvature angle θi, length Li and curvature radius Ri are stored in the memory unit 5b and used to calculate the curvature angle θi+1, length Li+1 and curvature radius Ri+1 of the next element i+1. Steps S12 to S16 are repeated until the sum of the lengths Li reaches the entire length of the wire 12, thereby obtaining the shapes θi, Li, Ri of all elements i.

[0052] In step S12, the displacement of the base end of the wire 12 decreases by dxi, so that the tension of the base end decreases from Tr_(i-1) to Tr_i, and the wire 12 relaxes to element i, that is, the operating region advances to element i.

[0053] Next, in step S13, the tension Ti of the element i is calculated. The maximum tension Tp at the base end is expressed by the following equation (1) using the tension Ti of each element i according to Euler's belt equation: μ is the friction coefficient, and θi is the curvature angle of element i.

number

number

[0054] Next, in step S14, the curvature angle θi of the element i is calculated. The curvature angle θi is obtained from the following formula (3).

number

[0055] Next, in step S15, the change in elongation dlk of each element k in the range of the operating region [1, i-1] is calculated. The change in elongation dlk of element k can be calculated from Hooke's law using the difference in tension dTk between the tension and relaxation of element k, as shown in the following formula (4). EA is the stiffness of the wire 12. dlk = Lk / EA × dTk (4) In step S15, the sum of the elongation changes dl1, dl2, . . . , dl(i-1) from element 1 to element i-1 is obtained.

[0056] Next, in step S16, the length Li and the radius of curvature Ri of the element i are calculated. The driving displacement dxi of the wire 12 is the sum of the changes in elongation dl1, dl2, ..., dli in the operating range [1:i] to which tension is transmitted. Therefore, as shown in the following formula (5), the change dli of element i is calculated as the difference between the displacement dxi and the sum of the changes in elongation dl1, dl2, ..., dli-1 from element 1 to element i-1.

number

[0057] From the above, the length Li and the curvature radius Ri of element i are obtained by the following equations (6) and (7), respectively.

number

[0058] A plurality of pieces of tension data may be weighted in estimating the shape of the flexible portion 13. The plurality of pieces of tension data may be obtained by performing the pulling and relaxing operations on one wire 12 a plurality of times, or may be obtained by performing the pulling and relaxing operations on a plurality of wires 12.

[0059] Among the multiple data, more reliable data is weighted more. Highly reliable data is, for example, data acquired using a wire 12 with a highly linear spring constant, data with a large tension, or data in which the drive speed of the wire 12 during the relaxation operation is slow. The greater the tension, the greater the amount of change in tension during the relaxation operation, and therefore the more reliable the data. Also, the slower the drive speed, the greater the data density, and therefore the more reliable the data.

[0060] In this way, by estimating the shape of flexible section 13 using multiple pieces of data weighted based on reliability, it is possible to suppress estimation errors in the shape of flexible section 13 and estimate the shape of flexible section 13 with higher accuracy.

[0061] Second embodiment Next, an endluminal device system, a control device, and a control method according to a second embodiment of the present invention will be described with reference to the drawings. 14, the endoluminal device system 200 according to this embodiment differs from the first embodiment in that a measurement wire 14 is provided in addition to the driving wire 17. In this embodiment, configurations different from the first embodiment will be described, and configurations common to the first embodiment will be denoted by the same reference numerals and description thereof will be omitted.

[0062] The endoluminal device system 200 comprises an endoluminal device 10 having a movable part 11 and one or more driving wires (second wires) 17, a measurement wire (first wire) 14 provided on the endoluminal device 10, a driving unit 2, a tension sensor (first sensor) 3 that detects the tension of the wires 14, 17, a displacement sensor (second sensor) 4 that detects the displacement of the measurement wire 14, and a control unit 5. In Fig. 14, the movable part 11 is a curved part. As shown in Fig. 16, the movable part 11 may be an end effector or a joint.

[0063] The flexible driving wire 17 has the same configuration as the wire 12 of the first embodiment, but has a different function. That is, the driving wire 17 of this embodiment is disposed within the flexible portion 13 along the longitudinal direction of the flexible portion 13, the tip of the driving wire 17 is fixed to the tip of the bending portion 11, and the base end of the driving wire 17 is connected to the driving device 2. The flexible driving wire 17 thus extending over the entire length of the flexible portion 13 bends into the same shape as the flexible portion 13 as the flexible portion 13 bends.

[0064] Unlike the wires 12 in the first embodiment, the driving wires 17 in this embodiment have a function of transmitting power given from the driving device 2 from the base end to the tip end to operate the movable part 11, but do not have a function of acquiring shape information of the flexible part 13. For example, four wires 17 are provided for bending the bending part 11 up, down, left, and right, respectively. In this embodiment, each of these four wires 17 is configured to be able to function as a driving wire, but does not function as a measurement wire.

[0065] The flexible measurement wire 14 is disposed in the flexible portion 13 in the longitudinal direction of the flexible portion 13, the tip of the measurement wire 14 is not connected to the movable portion 11 but is fixed to the tip of the flexible portion 13, and the base end of the measurement wire 14 is connected to the driving device 2. The measurement wire 14 has a function of acquiring shape information of the flexible portion 13, but does not have a function of transmitting power applied from the driving device 2 from the base end to the tip to operate the movable portion 11.

[0066] The driving device 2 has an actuator 2 a that moves the base end portion of each of the wires 14 , 17 backward and forward in the longitudinal direction of each of the wires 14 , 17 . The tension sensor 3 is provided at the base end of each of the wires 14, 17 and detects the tension at the base end of each of the wires 14, 17. The displacement sensor 4 detects the displacement of the base end of the measurement wire 14 in the longitudinal direction of the measurement wire 14 .

[0067] The coefficient of friction of the path of the measurement wire 14 is greater than the coefficient of friction of the path of the drive wire 17 . 15, an endoluminal device system 200 includes a tubular first sheath 15 into which a measurement wire 14 is inserted, and a tubular second sheath 16 into which a drive wire 17 is inserted. Each of the wires 14, 17 is movable in the longitudinal direction within the sheaths 15, 16. The coefficient of friction between the measurement wire 14 and the first sheath 15 is greater than the coefficient of friction between the drive wire 17 and the second sheath 16.

[0068] Other means of varying the coefficient of friction of the wire 14, 17 paths may be employed, such as lubricants, stranded / solid wire, or surface treatments. That is, the type of lubricant applied to wires 14, 17 may be selected so that the coefficient of friction of the path of measurement wire 14 is greater than the coefficient of friction of the path of drive wire 17. Alternatively, a solid wire may be used as drive wire 17, and a twisted wire may be used as measurement wire 14. Alternatively, the outer surface of measurement wire 14 may be subjected to a surface treatment that increases the coefficient of friction, such as a roughening treatment that forms an uneven structure.

[0069] In the control method of this embodiment, the processor 5a pulls and relaxes the measurement wire 14 in a pulling operation and a relaxing operation (step S2), acquires data on the tension and displacement of the measurement wire 14 during the relaxing operation (step S3), and adjusts the control parameters for the drive wire 17 based on the data (step S4).

[0070] Thus, according to this embodiment, a measurement wire 14 separate from the drive wire 17 is used, and the friction acting on the measurement wire 14 is greater than the friction acting on the drive wire 17. The smaller the friction acting on the drive wire 17, the higher the efficiency of power transmission from the base end to the tip end of the drive wire 17. On the other hand, the greater the friction acting on the measurement wire 14, the greater the change in tension at the base end of the measurement wire 14 during the relaxation operation. Therefore, the responsiveness of the movable section 11 can be improved, and the sensitivity of the tension to the shape of the flexible section 13 can be increased, improving the estimation accuracy of the shape of the flexible section 13 and the adjustment accuracy of the control parameters.

[0071] In this embodiment, the friction coefficient of the path of the measurement wire 14 is greater than the friction coefficient of the path of the drive wire 17, but alternatively or in addition to this, the spring constant of the measurement wire 14 may be smaller than the spring constant of the drive wire 17. The larger the spring constant of the drive wire 17, the faster the power is transmitted from the base end to the tip end of the drive wire 17. On the other hand, the smaller the spring constant of the measurement wire 14, the larger the change in displacement with respect to the change in tension, and the larger the displacement of the measurement wire 14 required for the traction and relaxation operations.

[0072] Therefore, by making the spring constant of the measurement wire 14 smaller than the spring constant of the drive wire 17, the responsiveness of the movable part 11 can be improved, and the sensitivity to displacement relative to the shape of the flexible part 13 can be increased, thereby improving the estimation accuracy of the shape of the flexible part 13 and the adjustment accuracy of the control parameters.

[0073] In this embodiment, the measurement wire 14 may be pulled and relaxed in the linear region of the spring characteristic of the measurement wire 14 . 17 shows an example of the spring characteristic of the measurement wire 14, where the horizontal axis represents the displacement of the measurement wire 14 and the vertical axis represents the tension of the measurement wire 14. In the case of the measurement wire 14 made of a stranded wire, the spring characteristic may include a region where the tension changes linearly (the region surrounded by the dashed ellipse) and a region where the tension changes nonlinearly.

[0074] According to this modification, it is possible to simplify the calculation of the shape of the flexible portion 13 and the calculation for adjusting the control parameters by using the linear region of the measurement wire 14. In addition, it is possible to more accurately calculate the shape of the flexible portion 13 and adjust the control parameters. In the case of the measurement wire 14 made of a single wire, the measurement wire 14 has spring characteristics in which the tension changes linearly over substantially the entire range of displacement. Therefore, when a single wire is used as the measurement wire 14, the measurement wire 14 may be pulled and relaxed in any linear range.

[0075] Third embodiment Next, an endluminal device system, a control device, and a control method according to a third embodiment of the present invention will be described with reference to the drawings. 18, the endoluminal device system 300 according to this embodiment differs from the first and second embodiments in that the endoluminal device 20 has multiple movable parts 11A, 11B. In this embodiment, configurations different from the first and second embodiments will be described, and configurations common to the first and second embodiments will be denoted by the same reference numerals and description thereof will be omitted.

[0076] The endoluminal device system 300 includes an endoluminal device 20 having two movable parts 11A, 11B and two or more wires (first wires) 12A, 12B, a drive unit 2 that drives the movable parts 11A, 11B by pulling and relaxing the wires 12A, 12B, a tension sensor (first sensor) 3 that detects the tension of each wire 12A, 12B, a displacement sensor (second sensor) 4 that detects the displacement of each wire 12A, 12B, and a control unit 5.

[0077] The movable parts 11A and 11B are, for example, any of a bending part, a joint, and an end effector. In the example of FIG. 18, the movable part 11A is an end effector, and the movable part 11B is a joint disposed between the end effector 11A and the tip of the flexible part 13.

[0078] The wires 12A and 12B are driving wires for operating the corresponding movable parts 11A and 11B, and also serve as measurement wires, similar to the wires 12 in the first embodiment. The tips of the wires 12A and 12B are fixed to the corresponding movable parts 11A and 11B, respectively, and the base ends of the wires 12A and 12B are connected to the driving device 2.

[0079] The driving device 2 has two or more actuators 2a that move the base ends of the wires 12A, 12B backward and forward in the longitudinal direction of the wires 12A, 12B. The tension sensor 3 is provided at the base end of each of the wires 12A, 12B, and detects the tension at the base end of each of the wires 12A, 12B. The displacement sensor 4 detects the displacement of the base end portion of each of the wires 12A, 12B in the longitudinal direction of the wires 12A, 12B.

[0080] In this embodiment, when the processor 5a operates one of the movable parts 11A and 11B, the processor 5a executes a control method to adjust the control parameters of the movable parts 11A and 11B. For example, the processor 5a acquires data on the tension and displacement of the wire 12B during the relaxation operation of the wire 12B accompanying the operation of the movable part 11B, and adjusts the control parameters of both the movable parts 11A and 11B based on the acquired data. In this way, according to this embodiment, when either of the movable parts 11A, 11B performs an operation required for a task such as a treatment, the control parameters for the other movable part 11A, 11B can also be adjusted.

[0081] In this embodiment, the processor 5a may execute the control method in response to a trigger, or may execute the control method repeatedly at a predetermined time interval, as in the first embodiment. In this case, the processor 5a may select any one wire from the predetermined plurality of wires 12A, 12B, and pull and relax the selected wire in the pulling and relaxing operations.

[0082] In this embodiment, the processor 5a may calculate the shape of the flexible portion 13 and adjust the control parameters based on multiple pieces of tension data. The multiple pieces of data are acquired by performing the pulling and loosening operations multiple times for one measurement wire 12, or by performing the pulling and loosening operations for multiple measurement wires 12. This configuration can improve the accuracy of the calculation of the shape of the flexible portion 13 and the adjustment of the control parameters. In the first and second embodiments described above, the processor 5a may also calculate the shape of the flexible section 13 and adjust the control parameters based on a plurality of pieces of tension data.

[0083] In the first to third embodiments described above, the endoluminal devices 1, 10, and 20 have the movable parts 11, 11A, and 11B, but as shown in Fig. 19, the endoluminal device 30 may not have a movable part. The tip of the measurement wire 14 is fixed to the tip of the flexible part 13. In this case, the processor 5a calculates the shape of the flexible part 13 after acquiring data on the tension and displacement of the measurement wire 14, and adjustment of the control parameters may be omitted. [Explanation of symbols]

[0084] 1,10,20 Endoluminal Device 2. Drive unit 3 Tension sensor (first sensor) 4 Displacement sensor (second sensor) 5. Control device 5a processor 11 Curved and movable parts 11A,11B Movable part 12 Wire (1st Wire) 12A, 12B (1st wire) 13 Soft part 14 Measurement wire (first wire) 15 First sheath 16 Second sheath 17 Drive wire (second wire) 100,200,300 Endoluminal Device System

Claims

1. an elongated and flexible endoluminal device; a flexible first wire disposed within the endoluminal device and longitudinally of the endoluminal device; a first sensor for detecting tension of the first wire; A drive device capable of pulling the first wire; At least one processor; a second sensor that detects a displacement of the first wire; The at least one processor: causing the driving device to perform a loosening operation for loosening the first wire that is being pulled; obtaining a tension in the first wire during the relaxation operation detected by the first sensor; obtaining a displacement of the first wire during the relaxation motion detected by the second sensor; An endoluminal device system that adjusts a control parameter of the endoluminal device based on a rate of change of the tension relative to the displacement during the relaxation motion.

2. The endoluminal device comprises a long and flexible soft section and a movable section connected to a tip of the soft section, The first wire is connected to the movable part, The endoluminal device system of claim 1 , wherein pulling and relaxing the first wire causes the movable part to move.

3. The endoluminal device system of claim 2 , wherein the at least one processor causes the driver to perform the relaxation motion without movement of the movable part.

4. A plurality of the first wires are provided, the movable portion is a bending portion, and the first wires are connected to the bending portion; The at least one processor: Before the execution of the relaxing operation, a first wire among the plurality of first wires is recognized as being pulled for bending the bending portion, and The endoluminal device system of claim 3, wherein the driver performs the relaxation operation without movement of the movable part by simultaneously relaxing the first wire being driven and the first wire opposing the first wire being driven.

5. A plurality of the first wires are provided, the movable portion is a bending portion, and the first wires are connected to the bending portion; The at least one processor: Before the execution of the relaxing operation, a first wire among the plurality of first wires is recognized as being pulled for bending the bending portion, and The endoluminal device system of claim 3 , wherein the driver performs the relaxation operation without movement of the movable part by relaxing any of the first wires other than the first wire being driven.

6. The endoluminal device comprises a long and flexible soft section, a movable section connected to a tip of the soft section, and a second wire disposed within the soft section in a longitudinal direction of the soft section, the first wire is not connected to the movable part, The endoluminal device system of claim 1 , wherein the second wire is connected to the movable portion.

7. a first sheath into which the first wire is inserted; a second sheath into which the second wire is inserted; 7. The endoluminal device system of claim 6, wherein a coefficient of friction between the first wire and the first sheath is greater than a coefficient of friction between the second wire and the second sheath.

8. The endoluminal device system of claim 6 , wherein the spring constant of the first wire is less than the spring constant of the second wire.

9. The endoluminal device system of claim 1 , wherein the control parameter is an amount of pulling and relaxing of the first wire to transmit tension to the tip of the first wire.

10. The endoluminal device system of claim 1 , wherein the at least one processor estimates a shape of the endoluminal device based on the rate of change.

11. A control device for an endoluminal device system, the endoluminal device system comprising: a long and flexible endoluminal device; a flexible first wire disposed in the endoluminal device in a longitudinal direction of the endoluminal device; a first sensor for detecting tension of the first wire; a drive device capable of pulling the first wire; and a second sensor for detecting displacement of the first wire; At least one processor; The at least one processor: causing the driving device to perform a loosening operation for loosening the first wire that is being pulled; obtaining a tension in the first wire during the relaxation operation detected by the first sensor; obtaining a displacement of the first wire during the relaxation motion detected by the second sensor; A controller that adjusts a control parameter of the endoluminal device based on the rate of change of the tension relative to the displacement during the relaxation motion.

12. the endoluminal device comprises a movable part; The control device of claim 11 , wherein the at least one processor causes the driver to perform the relaxation motion without movement of the moving part.

13. The endoluminal device system includes a plurality of the first wires, the movable portion is a bending portion, and the plurality of first wires are connected to the bending portion; The at least one processor: Before the execution of the relaxing operation, a first wire among the plurality of first wires is recognized as being pulled for bending the bending portion, and The control device according to claim 12 , wherein in the relaxing operation, the driven first wire and the first wire opposing the driven first wire are simultaneously relaxed.

14. 1. A method of operating a control device for controlling an endoluminal device, comprising: disposing a first flexible wire in the endoluminal device longitudinally of the device; The control device executes a relaxing operation to relax the first wire that is being pulled, The control device obtains a tension of the first wire during the relaxation operation; The control device obtains a displacement of the first wire during the relaxation operation; A method of operating a control device, the control device adjusting a control parameter of the endoluminal device based on a rate of change of the tension relative to the displacement during the relaxation motion.

15. the endoluminal device comprises a movable part; The method of claim 14, wherein the control device performs the relaxation action without movement of the movable part.

16. The endoluminal device includes a plurality of the first wires, the movable portion is a bending portion, and the plurality of first wires are connected to the bending portion; The control device recognizes, before the execution of the relaxation operation, a first wire among the plurality of first wires that is being pulled for bending the bending portion and is being driven, The method for operating a control device according to claim 15, wherein the control device performs the relaxation operation without movement of the movable part by simultaneously relaxing the first wire being driven and the first wire opposing the first wire being driven.

17. The endoluminal device includes a plurality of the first wires, the movable portion is a bending portion, and the plurality of the first wires are connected to the bending portion; The control device recognizes, before the execution of the relaxation operation, a first wire among the plurality of first wires that is being pulled for bending the bending portion and is being driven, The method for operating a control device according to claim 15 , wherein the control device performs the relaxation operation without movement of the movable part by relaxing any of the first wires other than the first wire being driven.

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