Tactile sensor, measuring method, tubular endoscopic tool and control method

Abstract

The invention discloses a tactile sensor, a measuring method, a tubular endoscopic tool and a control method. The tactile sensor comprises a sealed cavity formed by a deformable material, a signal processing unit and a pressure sensor arranged in the cavity. The cavity is filled with a fluid medium; the signal processing unit is arranged outside the cavity, and the pressure sensor is electrically connected with the signal processing unit. By using the sealed cavity formed by the deformable material, the sensitivity of the tactile sensor is improved, so that the sensor can more accurately detect the external pressure change. Meanwhile, the reliability of the sensor is also improved through the sealing design, and the influence of the external environment on the sensor is reduced. A simple design is used to realize adaptation to large-scale surface fluctuation characteristics of a measured object or the surface of a flexible measured object without a motion transmission part, and pressure positively correlated to the contact force of the measured object is obtained.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of sensors, in particular to a tactile sensor, a measurement method, a tubular endoscopic tool and a control method. BACKGROUND

[0002] In recent years, in the field of pressure sensors, the prior art such as capacitive elements based on piezoelectric effect, piezoresistive elements, or based on optical methods. However, these methods either have a large sensor that cannot be used in a small space, or have low sensitivity and accuracy, or can only measure one point and cannot accurately measure the pressure of a contact surface. The sensor of the prior art can only detect the local mechanical signal of the action point, especially when the measured object is deformable and flexible, or the size of the surface feature of the measured object is similar to or larger than the size of the sensor. The above problems can be solved by selecting a multi-degree-of-freedom sensor in the current disclosed technology, or by designing a mechanical structure with a guide, or a multi-sensor dense array, etc. However, this will bring problems such as large occupied volume, high cost, complex structure, low reliability and maintainability, and it is also difficult to miniaturize. SUMMARY

[0003] The technical problem to be solved by the present application is to overcome the defect that the prior art can only detect the local mechanical signal of the action point, and to provide a tactile sensor, a measurement method, a tubular endoscopic tool and a control method.

[0004] The present application solves the above technical problems by the following technical solutions:

[0005] The present application provides a tactile sensor, which comprises a sealed cavity formed by a deformable material, a signal processing unit and a pressure sensor arranged inside the cavity.

[0006] The cavity is filled with a fluid medium.

[0007] The signal processing unit is arranged outside the cavity, and the pressure sensor is electrically connected to the signal processing unit.

[0008] In this scheme, the tactile sensor can adapt to surfaces of different shapes and sizes due to the use of deformable material to form the cavity, providing more flexible application scenarios. By setting a pressure sensor inside the cavity, external tactile stimuli can be detected and responded to, thereby achieving force sensing and measurement. When external force acts on the cavity, the deformable material will deform, thereby changing the pressure of the fluid inside the cavity, and the pressure sensor can capture this change. The sealed design of the cavity can protect the internal pressure sensor from external environmental influences such as moisture, dust, or other mechanical damage, improving the stability and service life of the sensor. The fluid medium filled inside the cavity can enhance the sensitivity and uniformity of tactile sensing. Fluids can effectively transmit pressure, allowing the pressure sensor to more accurately detect small or uneven forces. The signal processing unit is located outside the cavity, facilitating signal reading and processing, while also avoiding the possibility of direct physical impact on the signal processing unit.

[0009] Preferably, the fluid medium has a constant preset pressure when the cavity is not subjected to extrusion.

[0010] The pressure sensor is used to obtain a pressure signal generated by the change in pressure of the fluid medium when the cavity is subjected to extrusion.

[0011] In this scheme, by maintaining a constant preset pressure of the fluid medium when the cavity is not subjected to extrusion, a stable reference state can be provided for the sensor. This allows the pressure sensor to accurately measure the pressure change caused by extrusion when detecting external extrusion.

[0012] Preferably, the signal processing unit is used to filter and amplify the pressure signal.

[0013] In this scheme, by filtering to remove noise and amplifying useful signals, the signal-to-noise ratio can be significantly improved, allowing the tactile sensor to more accurately perceive the size and changes of external forces. The filtered and amplified signal is more stable, reducing the risk of misoperation or false readings due to signal fluctuations, and improving the reliability of the entire tactile sensing system.

[0014] Preferably, the signal processing unit is also used to convert the pressure signal after the filtering and amplification processes into force information of the cavity.

[0015] In this scheme, converting the pressure signal into force information involves interpreting and analyzing the signal. The signal processing unit converts the electrical signal size output by the pressure sensor into the size and direction of the corresponding external force. This conversion requires calibration and calculation based on the design parameters and characteristics of the pressure sensor, as well as the physical properties of the cavity and fluid medium.

[0016] Preferably, the signal processing unit is further configured to obtain a projection area of the region of the cavity in contact with the external object in a preset force direction;

[0017] The signal processing unit is configured to calculate the force information according to the projection area and the pressure signal.

[0018] Preferably, the signal processing unit is further configured to store preset projection area information of the region of the cavity in contact with the external object in a preset force direction, and the signal processing unit is configured to calculate the force information according to the preset projection area information and the pressure signal.

[0019] In this scheme, the projection area is a design parameter in simple applications, and is fixed as a constant, i.e., a preset value, after design is completed.

[0020] In this scheme, by measuring the projection area of the contact region, the sensor can more accurately quantify the interaction between the external object and the contact surface of the sensor. Obtaining the contact area can help more accurately calculate the force applied on the sensor. Because force is equal to pressure multiplied by area, by measuring pressure (provided by the pressure sensor) and contact area, the total force size can be more accurately calculated. The combination of contact area and force information can improve the interaction ability of the sensor with the external environment, so that the sensor can more subtly perceive and respond to different touch situations, thereby improving the naturalness and intuitiveness of human-computer interaction. By obtaining the information of the contact area, the design of the sensor can be optimized to make it more suitable for specific application scenarios. For example, the sensitivity and resolution of the sensor can be adjusted according to the expected contact area. On the other hand, in combination with the contact area and the pressure signal, the signal processing unit can perform more complex data processing, such as force field reconstruction, object recognition, etc., thereby improving the intelligence level and autonomous decision-making ability of the system.

[0021] Preferably, the fluid medium is one of a gaseous medium or a liquid medium.

[0022] In this scheme, the gaseous medium has high compressibility and can quickly respond to external force changes, so it is suitable for application scenarios that require high response speed and sensitivity. The liquid medium, due to its incompressibility, can provide more stable pressure signals and is suitable for occasions that require accurate force measurement.

[0023] Preferably, the pressure sensor and the inner wall of the cavity are not in contact with each other when the cavity is in contact with the external object.

[0024] In this solution, the physical contact between the sensor and the inner wall of the cavity is reduced, reducing the risk of failure due to wear or adhesion, thus improving the overall reliability and stability of the sensor. Ensuring that the pressure sensor is not in contact with the inner wall when the cavity is in contact with an external object can significantly improve the durability, measurement accuracy and reliability of the tactile sensor, while simplifying the structural design and enhancing its performance in various applications. Contact between the sensor and the inner wall can cause uneven pressure distribution, resulting in measurement errors. Keeping the sensor away from the inner wall can reduce such errors and provide more reliable force information.

[0025] The present application also provides a method for measuring force information, which is realized by using the tactile sensor as described above, comprising the following steps:

[0026] acquiring a pressure signal through the pressure sensor when the tactile sensor is in contact with an external object;

[0027] acquiring the projection area of the region where the cavity of the tactile sensor is in contact with the external object in a preset force direction;

[0028] calculating the force information according to the projection area and the pressure signal.

[0029] In this solution, when the tactile sensor is in contact with an external object, the pressure sensor will sense the pressure changes caused by the contact and convert these changes into electrical signals. The electrical signals reflect the magnitude of the force exerted by the object on the sensor. By determining the projection area of the region where the tactile sensor is in contact with the external object in a preset force direction, the effective area of force action is obtained, and finally, the force information is calculated according to the acquired pressure signal and the projection area of the contact region. Generally, force is equal to pressure multiplied by area, so a comprehensive force assessment can be obtained, not just the pressure value. This method is suitable for objects of different shapes and sizes, as the contact area can be flexibly changed.

[0030] The present application also provides a tubular endoscopic tool, which comprises a catheter and a tactile sensor as described above, the tactile sensor being arranged on the outer surface of the catheter.

[0031] In this solution, by installing a tactile sensor on the outer surface of the catheter, the endoscopic tool can sense the contact situation in the body or other narrow spaces, including the contact force, contact area, etc., thus providing more comprehensive operation feedback. The tactile sensor can help doctors more accurately perceive and locate the position of the tool, especially in complex surgical environments, which helps to improve the accuracy and efficiency of the operation.

[0032] Preferably, the tactile sensor is arranged at the head end of the catheter, and the deformable cavity of the tactile sensor extends beyond the end face of the head end.

[0033] In this aspect, by placing the tactile sensor at the head end of the catheter and extending the deformable cavity beyond the end face of the head end, the sensor can be ensured to function at the location where tactile feedback is most needed, i.e. the contact point between the tool and the tissue. The tubular endoscopic tool is often used in narrow or difficult-to-observe environments, and the use of a tactile sensor can provide additional operation information to help the doctor better navigate and operate.

[0034] Preferably, the tactile sensor is a plurality, and the tactile sensors are equidistantly arranged along the circumference of the head end.

[0035] In this aspect, by evenly distributing multiple tactile sensors around the head end, a full-range perception of the force around the tool head end can be achieved. This helps to more accurately determine the contact between the tool and the surrounding tissue, thereby improving the accuracy of the operation. Multiple sensors can provide detailed information about the force distribution, which can be used by the doctor to assess the elasticity, hardness, and other characteristics of the tissue, which is crucial for certain diagnostic and surgical steps. The evenly distributed sensors can provide more stable force feedback, reduce the risk of errors or failures of a single sensor, and enhance the overall stability and reliability of the endoscopic tool.

[0036] Preferably, multiple rows of tactile sensors are arranged along the radial direction of the catheter.

[0037] In this aspect, by arranging multiple rows of tactile sensors in the radial direction of the catheter, the perception of radial force can be enhanced. This is very important for the tool to avoid excessive compression or damage to the surrounding tissue when operating in the body.

[0038] Preferably, the tactile sensor is used to obtain the force information between the head end and the wall of the lumen when the tubular endoscopic tool moves in the lumen, and the force information includes the magnitude of the force and the direction of the force.

[0039] In this aspect, by monitoring the magnitude and direction of the force in real time, the doctor can avoid applying excessive force to the lumen wall, reduce the risk of injury during surgery, and improve the safety of the surgery. Understanding the direction of the force between the head end and the lumen wall can help the doctor better navigate the movement path of the endoscopic tool in the lumen, especially in curved or complex lumens.

[0040] Preferably, the tubular endoscopic tool further comprises a controller electrically connected to the tactile sensor, and the controller is used to control the movement direction of the tubular endoscopic tool based on the force information.

[0041] In the present scheme, the real-time force information provided by the tactile sensor is received by the controller, which can automatically adjust the motion direction of the tubular endoscopic tool to adapt to the complex environment in the cavity. Automatic adjustment of the motion direction can reduce the risk of injury caused by improper manual operation, and improve the accuracy and safety of the operation.

[0042] The present application also provides a control method for a tubular endoscopic tool, which is implemented by using the tubular endoscopic tool as described above, and comprises the following steps:

[0043] When the tubular endoscopic tool moves in the cavity, the force information between the head end of the tubular endoscopic tool and the wall of the cavity is obtained by the tactile sensor;

[0044] According to the force information, the force direction of the tubular endoscopic tool is determined;

[0045] According to the force direction, the correction information of the motion direction of the tubular endoscopic tool is determined;

[0046] According to the correction information, the motion direction of the tubular endoscopic tool is adjusted to control the motion of the tubular endoscopic tool in the cavity.

[0047] The force information obtained by the tactile sensor can be fed back to the control method in real time, and the determination of the motion direction can be further verified or corrected by obtaining the force direction, so that the motion of the endoscopic tool can be adjusted according to the real-time force condition, improving the flexibility and response speed of the operation. The process of determining the force direction and the motion direction is based on accurate mechanical analysis, which helps to accurately control the endoscopic tool in the cavity and avoid unnecessary damage and complications. The control method can realize the automatic operation of the endoscopic tool, reduce the manual operation burden of the doctor, and especially in the complex cavity operation, can improve the operation efficiency and safety.

[0048] The positive progress effect of the present application is that the present application uses a sealed cavity formed by a deformable material to improve the sensitivity of the tactile sensor, so that the sensor can more accurately detect the change of external pressure. At the same time, the sealed design also improves the reliability of the sensor and reduces the influence of the external environment on the sensor. Using a simple design, the sensor can adapt to the large-scale surface undulation characteristics of the measured object or the surface of the flexible measured object without moving parts, and obtain the pressure that is positively related to the contact force of the measured object. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 It is a working schematic diagram of the pressure sensor in the prior art.

[0050] Figure 2 It is another working schematic diagram of the pressure sensor in the prior art.

[0051] Figure 3 A schematic diagram of the tactile sensor of embodiment 1 of the present application.

[0052] Figure 4 A schematic diagram of a specific example of embodiment 1 of the present application.

[0053] Figure 5 A schematic diagram of the working state of a specific example of embodiment 1 of the present application.

[0054] Figure 6 A schematic diagram of the force direction of a specific example of embodiment 1 of the present application.

[0055] Figure 7 A schematic diagram of the tubular endoscopic tool of embodiment 2 of the present application.

[0056] Figure 8 A schematic diagram of the force of the tubular endoscopic tool of embodiment 2 of the present application. DETAILED DESCRIPTION

[0057] The present application is further illustrated by the following examples, but is not limited to the examples.

[0058] Embodiment 1

[0059] A prior art pressure sensor is shown in FIG. 1, where the gray shaded part is the rough surface of the measured object, and P represents the pressure sensor, and the black rectangular frame connected to the pressure sensor represents the installation plane of the pressure sensor. The pressure sensor in the prior art can only detect the local mechanical signal of the action point, especially when the measured object is deformable and flexible, or the size of the surface feature of the measured object is similar to or larger than the size of the sensor. Figures 1-2 The scene shown in FIG. 2 is due to the rough surface of the measured object, the force direction of the sensor (arrow F direction) is inconsistent with the measurement direction (the long axis of the cylinder), which greatly affects the measurement result. Figure 1 The scene shown in FIG. 3 is due to the surface feature of the measured object first contacting the installation plane of the sensor, which causes the sensor to fail to measure the effective signal. The above problems can be solved by selecting a multi-degree-of-freedom sensor, or by designing a mechanical structure with a guide, or by a multi-sensor dense array scheme in the current disclosed technology, but all of them will bring problems such as large occupied volume, high cost, complex structure, low reliability and maintainability, and it is very difficult to miniaturize. Figure 2 The present embodiment provides a tactile sensor, as shown in FIG. 4.

[0060] Figure 3 ​As shown, the upper gray shaded part is the rough surface of the measured object, and the lower gray shaded part is the tactile sensor. The black rectangular frame connected to both ends of the tactile sensor represents the tactile sensor mounting plane. P represents the pressure sensor, and the multiple arrows represent the pressure of the filling fluid on the pressure sensor P. The rectangular frame connected to one end of the tactile sensor is the signal processing unit. The tactile sensor includes a sealed cavity formed by a deformable material, a signal processing unit, and a pressure sensor arranged inside the cavity; the cavity is filled with a fluid medium; the signal processing unit is arranged outside the cavity, and the pressure sensor is electrically connected to the signal processing unit. Among them, the fluid medium is one of gaseous medium or liquid medium. When the cavity contacts with the external object, the pressure sensor and the inner wall of the cavity are not in contact with each other.

[0061] In this embodiment, the pressure sensor is a mems micro pressure sensor. In other embodiments, other types of pressure sensors (usually larger) can also be used as long as the volume is small enough to meet the application requirements.

[0062] Among them, the deformable material can be selected from a variety of mature film materials according to the application scenario, without limitation. The area of the material should ensure that the sealed cavity can better surround the sensor. The thickness or elastic modulus of the material should ensure that the deformation of the sealed cavity under the maximum stress in the target application scenario will not cause the membrane material on the surface of the cavity to contact the sensor. Since the physical contact between the sensor and the inner wall of the cavity is reduced, the risk of failure due to wear or adhesion is reduced, thereby improving the overall reliability and stability of the sensor. Ensuring that the pressure sensor is not in contact with the inner wall when the cavity contacts with the external object can significantly improve the durability, measurement accuracy and reliability of the tactile sensor, while simplifying the structural design and enhancing its performance in various applications. Contact between the sensor and the inner wall can cause uneven pressure distribution, resulting in measurement errors. Keeping the sensor away from the inner wall can reduce such errors and provide more reliable stress information. Moreover, the pressure sensor can be provided with one or more, and only one is provided in this embodiment because the pressure in the connected fluid is equal everywhere. In other embodiments, two or more pressure sensors can be provided, and the readings of the multiple sensors are the same. In high reliability requirements, two can be used as redundancy. The position of the pressure sensor in the cavity has no special requirements because the pressure in the connected fluid is equal everywhere. No contact with the membrane body is required.

[0063] When the fluid medium is a liquid, it is sufficient to fill the cavity to maintain the shape and resist the gravity of the membrane. When the fluid medium is a gas, the gas pressure needs to be high enough to ensure that the membrane body is always in a tension state within the range. The specific pressure parameter can be determined according to the actual application scenario and the range.

[0064] In this embodiment, the fluid medium has a constant preset pressure when the cavity is not subjected to extrusion; the pressure sensor is used to obtain the pressure signal generated by the pressure change of the fluid medium when the cavity is subjected to extrusion.

[0065] By maintaining a constant preset pressure of the fluid medium when the cavity is not subjected to extrusion, a stable reference state can be provided for the sensor. This enables the pressure sensor to accurately measure the pressure change caused by extrusion when detecting external extrusion. The specific pressure parameters can be determined according to the actual application scenario and the range.

[0066] In this embodiment, the signal processing unit is used to filter and amplify the pressure signal. The signal processing unit filters, amplifies, and processes the signal, and then converts it into force information of the fluid bubble through an algorithm related to the installation method and shape of the fluid bubble, thereby realizing the measurement of the contact force. By filtering to remove noise and amplifying useful signals, the signal-to-noise ratio can be significantly improved, enabling the tactile sensor to more accurately perceive the size and change of external force. The filtered and amplified signal is more stable, reducing the risk of misoperation or false readings due to signal fluctuations, and improving the reliability of the entire tactile sensing system.

[0067] In this embodiment, the signal processing unit is also used to convert the filtered and amplified pressure signal into force information of the cavity.

[0068] Specifically, the signal processing unit is also used to obtain the projection area of the region of the cavity in contact with the external object in the preset force direction; and the signal processing unit is used to calculate the force information according to the projection area and the pressure signal. The product of the projection area and the pressure measured by the pressure sensor is the size of the force. In this embodiment, it should be noted that the force direction is preset. Because the sensor cannot distinguish the specific direction of the deformable sealed cavity under pressure. Only one direction can be preset, as long as the cavity is under pressure, it is considered to be under pressure in that direction. This is a concept of resolution, according to the application needs, more densely arranged deformable sealed cavities, the error between the preset direction and the actual direction is smaller. The deformable sealed cavity is fixed on the hard mounting base. Then the three-dimensional shape of the contact surface between the cavity and the mounting base is fixed, and the area projection in the direction of the preset force vector on the three-dimensional shape can be obtained by numerical integration through various mathematical calculation software, such as matlab or python or other scientific calculation programming research. Regular shape can also be manually derived and calculated.

[0069] The conversion of pressure signals into force information involves signal interpretation and analysis. The signal processing unit converts the electrical signal output by the pressure sensor into the size and direction of the external force according to the size of the electrical signal. This conversion requires calibration and calculation based on the design parameters and characteristics of the pressure sensor, as well as the physical properties of the cavity and fluid medium. By measuring the projected area of the contact region, the sensor can more accurately quantify the interaction between the external object and the sensor contact surface. Obtaining the contact area can help more accurately calculate the force applied to the sensor. Because force is equal to pressure multiplied by area, by measuring pressure (provided by the pressure sensor) and contact area, the total force size can be more accurately calculated.

[0070] The above scheme is suitable for more complex applications where the projected area changes with the force and requires real-time calculation by the signal processing unit.

[0071] In another implementation, i.e. in some simple application scenarios, the projected area is a design parameter that is fixed as a constant after design, and real-time calculation of the projected area is not required. The signal processing unit is also used to store preset projected area information of the area of the cavity in contact with the external object in the preset force direction, and the signal processing unit is used to calculate the force information according to the preset projected area information and the pressure signal. Therefore, the projected area is a preset value.

[0072] The haptic sensor provided in the embodiment can adapt to surfaces of different shapes and sizes, providing more flexible application scenarios, because the cavity is formed of a deformable material. By arranging a pressure sensor inside the cavity, the external haptic stimulus can be detected and responded to, thereby achieving force sensing and measurement. When external force acts on the cavity, the deformable material will deform, thereby changing the pressure of the fluid inside the cavity, and the pressure sensor can capture this change. The sealed design of the cavity can protect the internal pressure sensor from the influence of external environment, such as moisture, dust or other mechanical damage, thereby improving the stability and service life of the sensor. The fluid medium filled inside the cavity can enhance the sensitivity and uniformity of haptic sensing. Fluid can effectively transmit pressure, so that the pressure sensor can more accurately detect small or unevenly distributed forces. The signal processing unit is arranged outside the cavity, which facilitates signal reading and processing, and also avoids the possibility of direct physical impact on the signal processing unit.

[0073] The embodiment also provides a method for measuring force information using the above haptic sensor, comprising the following steps:

[0074] S1, obtaining a pressure signal through a pressure sensor when the haptic sensor is in contact with an external object;

[0075] S2, obtaining the projection area of the region where the cavity of the tactile sensor contacts the external object in the preset force direction;

[0076] S3, calculating the force information according to the projection area and the pressure signal.

[0077] When the tactile sensor contacts the external object, the pressure sensor can perceive the pressure change caused by the contact and convert the change into an electrical signal. The electrical signal reflects the magnitude of the force exerted by the object on the sensor. By determining the projection area of the region where the tactile sensor contacts the external object in the preset force direction, the effective area of the force action is obtained, and finally, the force information is calculated according to the obtained pressure signal and the projection area of the contact region. Generally, force is equal to pressure multiplied by area, so a comprehensive force evaluation can be obtained, not just the pressure value. This method is suitable for objects of different shapes and sizes, as the contact area can be flexibly changed.

[0078] The following will explain the tactile sensor of the embodiment and the method for measuring the force information realized by using the tactile sensor through a specific application.

[0079] As Figures 4-6 To arrange a tactile sensor on the clamping plane of the pincer tool instrument to measure the clamping force. Multiple tactile sensors can also be arranged in specific implementation. Figures 4-6 In the figure, the triangular component is a pincer tool instrument, the middle gray shaded part is the rough surface of the measured object, the tactile sensor is installed on the inner surface of one end of the pincer tool, P is the pressure sensor, and the arrow indicates the direction of the clamping force. There is also a pincer sheet on the upper surface of the tactile sensor.

[0080] The surface of the tactile sensor is made of materials such as silicone or rubber, which directly forms the clamping plane, or a material with higher rigidity is attached to the upper surface, such as stainless steel or tungsten steel pincer sheet, to meet the specific hardness or tooth shape requirements.

[0081] At the same time, the surface of the tactile sensor and the fixed base plate must be in close contact, ensuring that the contact area between the tactile sensor and the base plate remains unchanged when the tactile sensor deforms. When clamping is performed, the clamping force F and the liquid pressure P' have a unique relationship: F = P ′ *A, where the effective contact area A is the projection area of the contact area between the tactile sensor and the base plate in the clamping direction, and the projection direction is determined by the vector angle between the surface normal and the projection direction. Taking the rectangular contact fixation in the figure as an example:

[0082] When the clamping direction indicated by the arrow and the red labeled bottom surface angle is θ,

[0083] Effective contact area A = sinθ * a, where a is the area of the bottom surface marked in red.

[0084] By the above method, accurate measurement of the clamping force value can be obtained.

[0085] Embodiment 2

[0086] The embodiment provides a tubular endoscopic tool, Figure 7 An example of the tubular endoscopic tool provided by the embodiment is given. Figure 7 The upper and lower shadow parts in the middle are cavity walls constituting a cavity, the two black curves in the middle represent a catheter, and 1, 2, and 3 are a plurality of tactile sensors.

[0087] The tubular endoscopic tool includes a catheter and a tactile sensor as in Embodiment 1, which is arranged on the outer surface of the catheter. By mounting the tactile sensor on the outer surface of the catheter, the endoscopic tool can perceive the contact situation in the natural cavity of the human body or other narrow space, including the contact force, the contact area, etc., thereby providing more comprehensive operation feedback. It should be noted that the natural cavity of the human body is mostly a curved cavity, and the tubular endoscopic tool also integrates a viewing device (not shown in the figure). The catheter is made of flexible material to facilitate the tubular endoscopic tool to extend into the cavity, and the tactile sensor can help the doctor to more accurately perceive and locate the position of the tool, and further adjust the bending direction of the catheter according to the controller, which is particularly helpful to improve the accuracy and efficiency of the operation in a complex surgical environment.

[0088] The tactile sensor in the embodiment is arranged at the head end of the catheter, and the deformable cavity of the tactile sensor extends beyond the end surface of the head end. Arranging the tactile sensor at the head end of the catheter and making the deformable cavity extend beyond the end surface of the head end can ensure that the sensor functions at the position where tactile feedback is most needed, i.e., the contact point of the tool and the cavity tissue. The tubular endoscopic tool is usually used in a narrow or difficult-to-directly-observe environment, and the use of the tactile sensor can provide additional operation information to help the doctor better navigate and operate. In other embodiments, the tactile sensor can also be arranged on the outer surface of the tube body of the catheter.

[0089] In the embodiment, the tactile sensor is a plurality of tactile sensors, and the tactile sensors are equidistantly arranged along the circumference of the head end. The distance between each tactile sensor should be adapted to the surrounding environment. For example, if the surrounding environment has obvious undulations, the distance between each tactile sensor is as small as possible to ensure that in most cases a protrusion will not be positioned between two tactile sensors, resulting in complete non-contact with the tactile sensor, which will affect the measurement result. Further, at least three tactile sensors are evenly distributed along the circumference of the head end of the natural cavity flexible endoscope, and the distance between the tactile sensors is less than the typical size of the undulation of the surrounding tissue, which can be obtained according to the size obtained in the laboratory or practical experience.

[0090] In this embodiment, a plurality of rows of tactile sensors are arranged in the radial direction of the catheter. By arranging a plurality of rows of tactile sensors in the radial direction of the catheter, the sensing ability of the radial force can be enhanced. In other embodiments, only one row can be arranged.

[0091] In this embodiment, the tactile sensor is used to obtain the force information between the head end and the cavity wall when the tubular endoscopic tool moves in the cavity. The force information includes the magnitude of the force and the direction of the force. By monitoring the magnitude and direction of the force in real time, the doctor can avoid applying excessive force to the cavity wall, reduce the risk of injury during the operation, and improve the safety of the operation. By obtaining the direction of the force, the determination of the movement direction can be further verified or corrected. Understanding the direction of the force between the head end and the cavity wall can help the doctor better navigate the movement path of the endoscopic tool in the cavity, especially in curved or complex cavities.

[0092] In this embodiment, the tubular endoscopic tool further comprises a controller electrically connected with the tactile sensor, and the controller is used to control the movement direction of the tubular endoscopic tool according to the force information. By receiving the real-time force information provided by the tactile sensor through the controller, the movement direction of the tubular endoscopic tool can be automatically adjusted to adapt to the complex environment in the cavity. Automatic adjustment of the movement direction can reduce the risk of injury caused by improper manual operation, and improve the accuracy and safety of the operation.

[0093] This embodiment also provides a control method of a tubular endoscopic tool, which is implemented by using the above tubular endoscopic tool. The control method comprises the following steps:

[0094] S11, obtaining the force information between the head end of the tubular endoscopic tool and the cavity wall through the tactile sensor when the tubular endoscopic tool moves in the cavity;

[0095] S12, determining the force direction of the tubular endoscopic tool according to the force information;

[0096] S13, determining the correction information of the movement direction of the tubular endoscopic tool according to the force direction;

[0097] S14, adjusting the movement direction of the tubular endoscopic tool according to the correction information to control the movement of the tubular endoscopic tool in the cavity.

[0098] The force information obtained by the tactile sensors can be fed back to the control method in real time, and the determination of the movement direction can be further verified or corrected by obtaining the force direction, so that the movement of the endoscopic tool can be adjusted according to the real-time force condition, and the flexibility and response speed of the surgical operation are improved. The process of determining the force direction and the movement direction is based on accurate mechanical analysis, which helps to accurately control the endoscopic tool in the cavity, and avoids unnecessary damage and complications. The control method can realize the automatic operation of the endoscopic tool, reduce the manual operation burden of the doctor, and especially in complex cavity operation, can improve the surgical efficiency and safety.

[0099] Specifically, each tactile sensor can feedback the force between it and the surrounding environment. The vector direction of the force points to the center, and the included angle between adjacent vectors depends on the number and position of the tactile sensors. When n tactile sensors are evenly distributed along the circumference, the included angle is 360 / n degrees, and n is the number of tactile sensors. The vector sum of the measurement values of the n tactile sensors is the force size and direction of the front end of the endoscope in the radial direction. At the same time, the response of the tactile sensor beyond the front edge of the endoscope to the force in the front direction, the scalar sum of the n tactile sensors can be used as an approximation of the force in the forward or backward direction of the endoscope. The above results can be obtained to obtain the force vector of the endoscope head in all three translational degrees of freedom, which can be used as safety monitoring of excessive force, or controlled by the automatic mirror control algorithm to move in the opposite direction of the vector to realize automatic mirror control.

[0100] As Figures 7-8 For a specific example, the pipeline encounters an obstacle on the upper side, and the internal pressure of the fluid bubble on this side rises (tactile sensor 1), and its reading is higher than that of other internal sensors. Assuming that the three sensors are evenly distributed at an angle of 120 degrees on the circumference. Then, in the plane perpendicular to the pipeline axis, the unit vectors of the three fluid bubble measurement directions are multiplied by their pressure values (obtained by multiplying the sensor readings by the projection area in the direction) to obtain three components v_1, v_2, v_3 of the radial force of the pipeline.

[0101] The vector sum of the three components v_all=v_1+v_2+v_3 is the spatial resultant force of the pipeline at this time. The spatial resultant force is calculated in real time during the automatic mirror control, and the head of the pipeline is controlled to bend in the opposite direction of the resultant force while advancing. The bending amplitude can be simply positioned as a constant or positively related to the magnitude of the resultant force, so as to realize automatic obstacle avoidance. When the force is greater than the safety upper limit, it is considered that an obstacle that cannot be avoided is encountered, and the automatic operation is stopped to ensure safety. That is, when the force is too large and exceeds the safety upper limit, it is considered that the direction is blocked and cannot advance. Because a force vector can be obtained according to the above method, in the case where the safety upper limit is not exceeded, the direction indicated by the vector is turned to realize obstacle avoidance.

[0102] Although the specific embodiments of the present application have been described above, it is understood by those skilled in the art that the present application is only illustrated by way of example, and the scope of protection of the present application is defined by the appended claims. Those skilled in the art can make various changes or modifications to the embodiments without departing from the principles and essence of the present application, and such changes and modifications fall within the scope of protection of the present application.

Claims

1. A tactile sensor, characterized in that, The tactile sensor includes a sealed cavity formed of a deformable material, a signal processing unit, and a pressure sensor disposed inside the cavity; The cavity is filled with a fluid medium; The signal processing unit is located outside the cavity, and the pressure sensor is electrically connected to the signal processing unit.

2. The tactile sensor as described in claim 1, characterized in that, When the cavity is not compressed, the fluid medium has a constant preset pressure, and the pressure sensor is used to acquire the pressure signal generated by the pressure change of the fluid medium when the cavity is compressed; And / or, the signal processing unit is used to filter and amplify the pressure signal, and the signal processing unit is also used to convert the pressure signal after the filtering and amplification into the force information of the cavity.

3. The tactile sensor as described in claim 2, characterized in that, The signal processing unit is also used to obtain the projected area of ​​the region where the cavity contacts an external object in a preset force direction; The signal processing unit is used to calculate the force information based on the projected area and the pressure signal.

4. The tactile sensor as described in claim 2, characterized in that, The signal processing unit is also used to store the preset projected area information of the area where the cavity contacts the external object in the preset force direction, and the signal processing unit is used to calculate the force information based on the preset projected area information and the pressure signal.

5. The tactile sensor as described in claim 1, characterized in that, The fluid medium is either a gaseous medium or a liquid medium; And / or, when the cavity comes into contact with an external object, the pressure sensor does not come into contact with the inner wall of the cavity.

6. A method for measuring force information, characterized in that, The measurement method is implemented using a tactile sensor as described in any one of claims 1-5, and includes the following steps: When the tactile sensor comes into contact with an external object, it acquires a pressure signal through the pressure sensor. Obtain the projected area of ​​the area where the cavity of the tactile sensor contacts the external object in a preset force direction; The force information is calculated based on the projected area and the pressure signal.

7. A tubular endoscopic tool, characterized in that, The tubular endoscope includes a catheter and a tactile sensor as described in any one of claims 1-5, the tactile sensor being disposed on the outer surface of the catheter.

8. The tubular endoscopic tool as described in claim 7, characterized in that, The tactile sensor is located at the tip of the catheter, and the deformable cavity of the tactile sensor extends beyond the end face of the tip.

9. The tubular endoscopic tool as described in claim 8, characterized in that, The tactile sensors are multiple and are equidistantly arranged along the circumference of the head end; And / or, multiple rows of the tactile sensors are provided along the radial direction of the conduit.

10. The tubular endoscopic tool as described in claim 9, characterized in that, The tactile sensor is used to acquire force information between the tip and the cavity wall when the tubular endoscope moves within the cavity. The force information includes the magnitude and direction of the force.

11. The tubular endoscopic tool as described in claim 10, characterized in that, The tubular endoscope also includes a controller, which is electrically connected to the tactile sensor. The controller is used to control the movement direction of the tubular endoscope based on the force information.

12. A control method for a tubular endoscopic tool, characterized in that, The control method is implemented using the tubular endoscopic tool as described in any one of claims 7-11, and the control method includes the following steps: When the tubular endoscope moves within the cavity, the tactile sensor acquires the force information between the tip of the tubular endoscope and the cavity wall. The direction of force on the tubular endoscope is determined based on the force information. Correction information for determining the movement direction of the tubular endoscope based on the direction of the applied force; The direction of movement of the tubular endoscope is adjusted according to the correction information to control the movement of the tubular endoscope within the cavity.

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