Instrument device contact detection method, apparatus, and system

Abstract

The present application relates to the technical field of medical devices, and provides a medical device contact point detection method and device, electronic equipment and storage medium, which determines multiple facets in a facet simplification manner, and subsequently operates each facet individually, simplifies the complex high-order surface of the device into a plane, avoids solving the complex high-order surface equation, and simplifies the calculation process. Moreover, coordinate constraints in the facets are added, which makes it easier to constrain the contact point position on the three-dimensional plane. In addition, the detection model established by the plane equation and the moment formula has an analytical solution, which can easily calculate the three-dimensional coordinates of the initial contact point in each facet, and further determine the real contact point in each facet, thereby improving the calculation accuracy.

Description

Technical Field

[0001] This invention relates to the field of contact detection technology, and in particular to a method, apparatus and system for detecting contact points of instruments and equipment. Background Technology

[0002] Touch is one of the richest sensory perceptions in humans. In situations where visual information is insufficient, perceiving the location of contact (the point of contact) is crucial for operation. In surgical robots operating medical instruments, such as clamping rigid medical instruments like endoscopes and ultrasound probes, real-time acquisition of the patient's body posture is necessary. However, current hardware limitations mean that depth vision sensors have low update frequencies and cannot respond promptly to complex and dynamic changes in the human body environment. Furthermore, the field of view of vision sensors is easily obstructed, leading to information loss. These limitations restrict the use of vision sensors. Therefore, mimicking human tactile perception and perceiving the location of contact from tactile information obtained from six-dimensional force sensors is crucial for surgical robots to perform tasks in complex and dynamic environments. Intrinsic tactile perception technology calculates the center of mass of contact based on six-dimensional force information and contact surface geometry, i.e., contact point detection.

[0003] Existing contact detection methods mainly include the geometric method (wrench-axis method) and the iterative method. However, the geometric method is only suitable for single-point contact. When the surgical robot moves, the friction between the rigid medical device and the patient's body surface generates local torque, making the geometric method unsolvable. Therefore, the geometric method is only applicable to static point contact, limiting its application scenarios. The iterative method requires inputting the model equations of the rigid medical device's outer surface. However, most medical device outer surfaces are irregular, making it difficult to establish equations to describe them. This easily introduces higher-order terms, increasing computational complexity and compromising the accuracy of the calculation results. Furthermore, both the geometric and iterative methods suffer from computational complexity and poor real-time performance, making them unsuitable for the complex dynamic environment of surgical robots. Summary of the Invention

[0004] This invention provides a method, apparatus, and system for detecting contact points of medical devices, in order to overcome the deficiencies existing in the prior art.

[0005] This invention provides a method for detecting contact points in medical devices, comprising:

[0006] The device is equipped with a surface-patterned contact detection area, which is then simplified into multiple patches. The device is connected to a six-dimensional force sensor.

[0007] Based on the plane equations of the multiple facets in the sensor coordinate system of the six-dimensional force sensor and the torque formulas of the multiple facets in the sensor coordinate system, a detection model is established, and based on the acquisition results of the six-dimensional force sensor, the detection model is solved to obtain the three-dimensional coordinates of the initial contact point of the instrument in the multiple facets.

[0008] Based on the three-dimensional coordinates and the coordinate constraints of each point within the plurality of facets in the sensor coordinate system, the actual contact points within the plurality of facets are determined.

[0009] According to a method for detecting contact points in a medical device provided by the present invention, the step of simplifying the contact detection area into multiple patches to obtain a plurality of patches of the contact detection area includes:

[0010] Based on the edge collapse algorithm, the contact detection area is simplified into multiple patches; the cost function of the edge collapse algorithm is determined based on the length of the edges in the multiple patches and the curvature change around the removed point.

[0011] According to a device contact detection method provided by the present invention, the torque formula of the plurality of facets in the sensor coordinate system includes the sub-torque formulas of the plurality of facets corresponding to each dimension of the sensor coordinate system;

[0012] The sub-torque formula is used to characterize the relationship between the torque, force, lever arm, and local torque of the contact points within the plurality of facets in the corresponding dimensions.

[0013] According to the present invention, a method for detecting contact points of a medical device includes solving a detection model based on the acquisition results of the six-dimensional force sensor to obtain the three-dimensional coordinates of the initial contact points of the medical device within the plurality of surfaces, comprising:

[0014] The collected results are corrected based on the gravity compensation algorithm to obtain the corrected results;

[0015] Based on the correction results, the detection model is solved to obtain the three-dimensional coordinates.

[0016] According to a method for detecting contact points in a medical device provided by the present invention, determining the actual contact points within the plurality of surface patches based on the three-dimensional coordinates and the coordinate constraints of each point within the plurality of surface patches in the sensor coordinate system includes:

[0017] For any facet, if the three-dimensional coordinates of the initial contact point within the facet satisfy the coordinate constraints corresponding to the facet, then the initial contact point is determined to be the actual contact point within the facet.

[0018] According to the present invention, a method for detecting contact points of medical devices is provided, wherein the medical devices include medical devices.

[0019] The present invention also provides a device for detecting contact points of medical devices, comprising:

[0020] A patch simplification module is used to acquire the patched contact detection area of ​​the instrument, and to simplify the patch of the contact detection area to obtain multiple patches of the contact detection area; the instrument is connected to a six-dimensional force sensor;

[0021] The model solving module is used to establish a detection model based on the plane equations of the multiple facets in the sensor coordinate system of the six-dimensional force sensor and the torque formulas of the multiple facets in the sensor coordinate system, and to solve the detection model based on the acquisition results of the six-dimensional force sensor to obtain the three-dimensional coordinates of the initial contact point of the instrument in the multiple facets.

[0022] The contact detection module is used to determine the actual contact points within the multiple facets based on the three-dimensional coordinates and the coordinate constraints of each point within the multiple facets in the sensor coordinate system.

[0023] The present invention also provides a medical device contact detection system, comprising: a six-dimensional force sensor and the above-mentioned medical device contact detection device;

[0024] The six-dimensional force sensor is installed between the instrument and its control device to collect force information when the instrument comes into contact with the target object and obtain the collection results.

[0025] The six-dimensional force sensor is connected to the contact detection device of the instrument.

[0026] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the device contact detection method as described above.

[0027] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the device contact detection method as described above.

[0028] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the device contact detection method as described above.

[0029] The present invention provides a method, apparatus, and system for detecting contact points in medical devices. This method simplifies the detection of multiple surfaces by using a surface-simplification approach, and then operates on each surface individually. This simplifies the complex, high-order curved surfaces of the medical device into planes, avoiding the need to solve complex high-order surface equations and simplifying the calculation process. Furthermore, the addition of coordinate constraints within the surface areas makes it easier to constrain the contact point positions on a three-dimensional plane. In addition, the detection model established using plane equations and torque formulas has analytical solutions, allowing for easy calculation of the three-dimensional coordinates of the initial contact points within each surface area, thereby determining the actual contact points within each surface area and improving calculation accuracy. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on the drawings described below without creative effort.

[0031] Figure 1 This is one of the flowcharts illustrating the device contact detection method provided by the present invention;

[0032] Figure 2 This is a schematic diagram illustrating the process of determining the patch-like contact detection area of ​​a medical ultrasonic probe in the medical device contact detection method provided by the present invention.

[0033] Figure 3 This is a schematic diagram illustrating the process of determining the patch-like contact detection area of ​​a traditional Chinese medicine endoscope in the instrument contact detection method provided by the present invention.

[0034] Figure 4 This is the second flowchart of the instrument contact detection method provided by the present invention;

[0035] Figure 5 This is a schematic diagram of the structure of the instrument contact detection device provided by the present invention;

[0036] Figure 6 This is a schematic diagram of the structure of the instrument and equipment contact detection system provided by the present invention;

[0037] Figure 7 This is a schematic diagram of the installation position of the six-dimensional force sensor in the instrument contact detection system provided by the present invention;

[0038] Figure 8 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0040] Existing contact detection methods mainly include geometric methods and iterative methods.

[0041] The geometric method is as follows:

[0042] According to the definition of torque:

[0043] m=r×f (1)

[0044] Where m is the torque, f is the force, and r is the position of the point of application of the force, the following detection model can be established using formula (1):

[0045]

[0046] Where f and m are the force and torque measured by the six-dimensional force sensor, p is the contact force at the contact point, and r is the coordinate of the contact point in the six-dimensional force sensor coordinate system. Combining the two equations, the coordinates of the contact point can be obtained:

[0047]

[0048] Here, r represents the contact point coordinates lying on a straight line that passes through point r0, is parallel to f, and has a parameter of λ. This straight line is called the wrench-axis. The geometric method obtains the wrench-axis based on the detection model and transforms it into the coordinate system of the rigid medical device model. The intersection of the wrench-axis and the rigid medical device model is calculated using spatial geometric relationships, which is the contact centroid.

[0049] However, the geometric method is only applicable to single-point contact situations. When the surgical robot moves, the friction between the rigid medical instrument and the patient's body surface generates local torque, making the geometric method unsolvable. Therefore, the geometric method is only applicable to static point contact, limiting its application scenarios.

[0050] The iterative method is as follows:

[0051] When rigid medical devices come into contact with the environment, there is often a situation of high friction and soft contact. In this case, the local torque correction formula (2) is introduced to obtain formula (4):

[0052]

[0053] Where q represents the local torque at the contact point, the direction of q is parallel to the normal of the rigid medical device's outer surface at the contact centroid, and its magnitude is determined by the local torque parameter k. Based on this, the iterative method first models the outer surface to obtain the outer surface model S(c), from which the detection model can be established:

[0054]

[0055] Where r = [x, y, z] represents the three-dimensional coordinates of the contact point in the sensor coordinate system, and k represents the local torque parameter, used to characterize the magnitude of the local torque. Let:

[0056] X = [x, y, z, k] T (6)

[0057] Let formula (5) be denoted as g(X) = 0. The outer surface model is generally a quadratic or more complex surface, so g(X) is nonlinear. The extreme value of g(X) is solved iteratively using the Levenberg-Marquardt algorithm to obtain the coordinates of the contact point.

[0058] As can be seen from the above process, the iterative method requires inputting the model equations of the rigid medical device's outer surface. However, most medical device outer surfaces are irregular, making it difficult to establish equations to describe them. This easily introduces higher-order terms, increasing computational complexity and failing to guarantee the accuracy of the calculation results. Furthermore, both the geometric and iterative methods suffer from computational complexity and poor real-time performance, making them unsuitable for the complex dynamic environments of surgical robots.

[0059] Based on this, this invention provides a method for detecting contact points of medical devices to solve the technical problems existing in the above methods. To address the issues of inability to add positional constraints and slow computation in iterative methods, this invention proposes a multi-plane fitting method for the outer surface of rigid medical devices. The theoretical basis is that all surfaces can be fitted using infinitely subdivided triangular facets. While ensuring accuracy, the high-order outer surface model equations are reduced to first-order plane equations. Matrix solving provides fast speed and high accuracy, and constraints can be easily added, allowing the contact centroid to be constrained within a certain plane based on coordinates.

[0060] Figure 1 This is a flowchart illustrating a method for detecting contact points of a medical device provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the method includes:

[0061] S1, acquire the patched contact detection area of ​​the instrument, and simplify the patch of the contact detection area to obtain multiple patches of the contact detection area; the instrument is connected to a six-dimensional force sensor;

[0062] S2, based on the plane equations of the multiple facets in the sensor coordinate system of the six-dimensional force sensor and the torque formulas of the multiple facets in the sensor coordinate system, a detection model is established, and based on the acquisition results of the six-dimensional force sensor, the detection model is solved to obtain the three-dimensional coordinates of the initial contact point of the instrument in the multiple facets;

[0063] S3. Based on the three-dimensional coordinates and the coordinate constraints of each point within the plurality of facets in the sensor coordinate system, determine the actual contact points within the plurality of facets.

[0064] Specifically, the instrument contact detection method provided in this embodiment of the invention is executed by an instrument contact detection device. This device can be configured in the control device or server of the instrument. The server can be a local server or a cloud server. The local server can be a computer, tablet computer, etc., and this embodiment of the invention does not make specific limitations on this.

[0065] First, step S1 is executed to obtain the patched contact detection area of ​​the medical device. This device can be a medical instrument, such as a medical ultrasound probe, medical endoscope, surgical forceps, beauty device, or other rigid medical instruments. When used, the device needs to come into contact with the target object; the contact detection area is the area that may come into contact with the target object, typically the head of the device. For example, if the device is a medical ultrasound probe, the contact detection area is the area where the medical ultrasound probe may come into contact with the patient's body surface.

[0066] The contact detection area can be obtained by dividing the instrument model into regions. The instrument model can be a stereolithography (STL) model. The contact detection area can be composed of a large number of initial facets, and the shape of the initial facets can be triangular.

[0067] Because segmenting the STL model results in a high level of detail in the contact detection region, the initial number of facets is enormous and difficult to process. Therefore, it is necessary to further simplify the number of facets while maintaining the contact mechanical properties. Consequently, the contact detection region is simplified into multiple facets. Software such as Autodesk Maya or Geomagic can be used for facet simplification. Each simplified facet is triangular in shape, and the area of ​​each simplified facet is greater than or equal to the area of ​​the initial facet.

[0068] like Figure 2As shown, if the device is a medical ultrasound probe, the medical ultrasound probe model 11 is segmented to obtain a contact detection area containing a large number of initial facets, and then simplified to obtain a contact detection area containing multiple facets. For example... Figure 3 As shown, if the instrument is a medical endoscope, the medical endoscope model 21 is divided into regions to obtain a contact detection area containing a large number of initial facets, and then simplified to obtain a contact detection area containing multiple facets.

[0069] The medical device can be connected to a six-dimensional force sensor, specifically via a sensor transition plate. The six-dimensional force sensor can then be connected to the end flange of the control unit of the medical device via a sensor connector. This six-dimensional force sensor can collect force information when the medical device comes into contact with a target object. The collected results can include three-dimensional contact force {f}. x ,f y ,f z} and three-dimensional torque {m x ,m y ,m z}

[0070] Next, step S2 is executed, first determining the plane equations of each facet in the sensor coordinate system of the six-dimensional force sensor, and the plane equation S of the nth facet in the sensor coordinate system. n It can be represented as:

[0071] S n (x,y,z)=a n x+b n y+c n z+d n =0 (7)

[0072] Where x, y, and z are the x-axis, y-axis, and z-axis coordinates in the sensor coordinate system, respectively, and a n b n c n d n All are constants, and n takes values ​​from 1 to N, where N is the number of patches.

[0073] In this embodiment of the invention, the sensor coordinate system coincides with the end coordinate system of the control device of the six-dimensional force sensor, and the axial direction of the instrument coincides with the z-axis direction of the sensor coordinate system.

[0074] By combining the plane equations of each facet in the sensor coordinate system of the six-dimensional force sensor and the torque formulas of each facet in the sensor coordinate system, a detection model can be established. The detection model can be expressed as:

[0075]

[0076] Where k is the local torque parameter of the contact point within the nth facet.

[0077] As can be seen from formula (8), the torque formula for each facet in the sensor coordinate system can include the sub-torque formula for each facet corresponding to each dimension of the sensor coordinate system, that is, the sub-torque formulas for the three dimensions of x, y, and z axes, which are the first three formulas in formula (8). Each sub-torque formula is used to characterize the relationship between the torque, force, lever arm, and local torque of the contact points in the corresponding dimensions of multiple facets.

[0078] Based on formula (7), formula (8) can be simplified to obtain formula (9):

[0079]

[0080] Formula (9) can be further simplified to matrix form, that is:

[0081] AX = B

[0082]

[0083] By combining the data collected by the six-dimensional force sensor, A and B can be determined, and then the detection model can be solved to obtain the three-dimensional coordinates of the initial contact points of the instrument within multiple surfaces, i.e., x, y, and z in X. It can be understood that each surface may or may not contain an initial contact point. For a surface containing an initial contact point, there can be one or more such points, in which case X is a vector combination containing at least one vector.

[0084] Finally, step S3 is executed. Combining the initial three-dimensional coordinates of the contact points with the coordinate constraints of each point within each facet in the sensor coordinate system, the actual contact points within multiple facets are determined. Here, the coordinate constraints of each point within the nth facet in the sensor coordinate system can be expressed as Q. n The coordinate constraint is that the three-dimensional coordinates of each point satisfy the plane equation of the surface in which it is located.

[0085] When determining the actual contact point within the nth facet, we can directly check whether the three-dimensional coordinates of the initial contact point within the nth facet satisfy the coordinate constraints corresponding to the nth facet. If they do, the initial contact point is determined to be the actual contact point; otherwise, it is considered that the initial contact point is not the actual contact point.

[0086] The device contact detection method provided in this embodiment of the invention first obtains the device's patch-based contact detection area, and then simplifies the contact detection area into multiple patches. Next, based on the plane equations of these patches in the sensor coordinate system of a six-dimensional force sensor and the torque formulas of the patches in the same sensor coordinate system, a detection model is established. Based on the data collected by the six-dimensional force sensor, the detection model is solved to obtain the three-dimensional coordinates of the initial contact points of the device within the multiple patches. Finally, combining the three-dimensional coordinates and the coordinate constraints of each point within the multiple patches in the sensor coordinate system, the actual contact points within the multiple patches are determined. This method determines multiple patches through patch simplification, and then operates on each patch individually, simplifying the complex high-order curved surface of the device into a plane, avoiding the need to solve complex high-order surface equations, and simplifying the calculation process. Furthermore, the addition of coordinate constraints within the patches makes it easier to constrain the contact point positions on a three-dimensional plane. Furthermore, the detection model established using the plane equation and torque formula has an analytical solution, which can easily calculate the three-dimensional coordinates of the initial contact points in each facet, thereby determining the actual contact points in each facet and improving calculation accuracy.

[0087] Based on the above embodiments, the medical device contact detection method provided in this embodiment of the invention, wherein the contact detection area is simplified into multiple patches, including:

[0088] Based on the edge collapse algorithm, the contact detection area is simplified into multiple patches; the cost function of the edge collapse algorithm is determined based on the length of the edges in the multiple patches and the curvature change around the removed point.

[0089] Specifically, in this embodiment of the invention, when simplifying the contact detection area into patches, an edge collapse algorithm can be used to obtain multiple patches of the contact detection area.

[0090] The edge collapse algorithm is an iterative algorithm that removes the edge that minimizes mesh change in the current contact detection region, causing the two endpoints to coincide. This process is repeated until the target number of facets is reached. This target number of facets can be set according to different contact detection requirements; the larger the target number of facets, the higher the contact detection accuracy.

[0091] The edge collapse algorithm introduces a cost function to evaluate the cost of edge collapse. Let u and v be the two vertices of an edge in the touch detection region. Then the cost function cost(u,v) for collapsing from u to v (i.e. removing vertex u) is as follows:

[0092]

[0093] Among them, T u T is the set of all faces containing vertex u.uv It is the set of all faces that simultaneously contain vertices u and v. f.normal is the normal vector of face f that simultaneously contains vertices u and v. n.normal is the normal vector of face n that simultaneously contains vertices u and v. ||uv|| represents the distance between vertices u and v, that is, the length of the edge formed by connecting vertices u and v.

[0094] The cost function consists of two parts: one part is the length of the edge, where the shorter the edge, the smaller the detail and the more likely it should be removed; the other part is the curvature change around the point to be removed (vertex u), where the more gradual the curvature change, the more likely it should be removed.

[0095] The edge collapse algorithm is applied to remove the edge with the minimum cost each time, and this process is iterated until it is simplified to the target number of facets.

[0096] Based on the above embodiments, the medical device contact point detection method provided in this embodiment of the invention, wherein the detection model is solved based on the acquisition results of the six-dimensional force sensor to obtain the three-dimensional coordinates of the initial contact point of the medical device within the plurality of surfaces, includes:

[0097] The collected results are corrected based on the gravity compensation algorithm to obtain the corrected results;

[0098] Based on the correction results, the detection model is solved to obtain the three-dimensional coordinates.

[0099] Specifically, since gravity always points vertically downwards, but the posture of the equipment changes, the component of the equipment's weight on the six-dimensional force sensor varies with the posture. Therefore, it is necessary to eliminate the influence of gravity. In this embodiment of the invention, a gravity compensation algorithm is introduced to correct the collected data, yielding a corrected result. Specifically, the control device is allowed to move the equipment freely without contacting any object, and the sensor data is recorded. Then, the center of gravity and compensation parameters of the equipment are calculated using the least squares method. By combining the center of gravity and compensation parameters, the collected data can be corrected to offset the influence of gravity.

[0100] Subsequently, based on the correction result, the detection model can be solved to obtain more accurate three-dimensional coordinates.

[0101] In this embodiment of the invention, a gravity compensation algorithm is introduced, which can eliminate the interference of gravity on the six-dimensional force sensor caused by changes in the posture of the instrument, and make the obtained three-dimensional coordinates more accurate.

[0102] Figure 4 This is a complete structural schematic diagram of the instrument contact detection method provided in the embodiments of the present invention, as shown below. Figure 4As shown, the method includes:

[0103] Determine the three-dimensional model of the instrument in the sensor coordinate system;

[0104] The 3D model is segmented to obtain patch-like contact detection areas;

[0105] Simplified dough sheets;

[0106] Calculate the plane equation of the patch;

[0107] The acquisition results were obtained using a six-dimensional force sensor;

[0108] The collected results are corrected using a gravity compensation algorithm to obtain the corrected results.

[0109] A detection model is established based on the plane equation and the correction results;

[0110] By solving the detection model, the three-dimensional coordinates of the actual contact points in the patch are obtained.

[0111] In summary, the medical device contact detection method provided in the embodiments of the present invention has the following beneficial effects:

[0112] (1) Avoid solving complex high-order surface equations and simplify calculations. The outer surfaces of medical devices are mostly complex curved surfaces, making it difficult to establish accurate model equations. Introducing high-order surface equations will also increase computational complexity. This method is based on the principle of triangular facet segmentation of curved surfaces. It uses a set of three-dimensional planes to fit the outer surface of medical devices, replacing the modeling process of existing methods. It reduces the high-order surface equations to first-order plane equations and introduces matrix methods to solve them, simplifying calculations and improving the real-time performance of the algorithm.

[0113] (2) It is difficult to add constraints to higher-order surface equations, but it is easier to constrain the three-dimensional coordinates of the contact point on a three-dimensional plane. It is very important to determine whether the contact point coordinates are within the range where contact may actually occur. Due to their geometric properties, higher-order surface equations are difficult to determine in the later stage and cannot constrain the contact point coordinates during the solution process. The first-order three-dimensional plane equation in this method can determine whether the contact point is in the current plane by the coordinate range, thereby constraining the contact point within the range where contact may occur and improving the robustness of the algorithm.

[0114] (3) It has analytical solutions and high computational accuracy. Existing iterative solution algorithms are prone to getting stuck in local optima and oscillating around the optimal solution. This method introduces a matrix method to solve the multivariate homogeneous equation system, which has analytical solutions and improves computational accuracy. Especially in narrow and slender rigid interventional medical devices, such as endoscopes, the accuracy of contact detection plays a crucial role in the motion control of the device.

[0115] like Figure 5As shown, based on the above embodiments, this embodiment of the invention provides a medical device contact detection device, comprising:

[0116] The patch simplification module 51 is used to acquire the patched contact detection area of ​​the instrument and simplify the patch of the contact detection area to obtain multiple patches of the contact detection area; the instrument is connected to a six-dimensional force sensor;

[0117] The model solving module 52 is used to establish a detection model based on the plane equations of the multiple facets in the sensor coordinate system of the six-dimensional force sensor and the torque formulas of the multiple facets in the sensor coordinate system, and to solve the detection model based on the acquisition results of the six-dimensional force sensor to obtain the three-dimensional coordinates of the initial contact point of the instrument in the multiple facets.

[0118] The contact detection module 53 is used to determine the actual contact points within the multiple facets based on the three-dimensional coordinates and the coordinate constraints of each point within the multiple facets in the sensor coordinate system.

[0119] Based on the above embodiments, the medical device contact detection device provided in this embodiment of the invention, wherein the simplified surface module is specifically used for:

[0120] Based on the edge collapse algorithm, the contact detection area is simplified into multiple patches; the cost function of the edge collapse algorithm is determined based on the length of the edges in the multiple patches and the curvature change around the removed point.

[0121] Based on the above embodiments, the instrument contact detection device provided in this embodiment of the invention includes a torque formula for the plurality of facets in the sensor coordinate system, which includes a sub-torque formula for each dimension of the sensor coordinate system corresponding to the plurality of facets.

[0122] The sub-torque formula is used to characterize the relationship between the torque, force, lever arm, and local torque of the contact points within the plurality of facets in the corresponding dimensions.

[0123] Based on the above embodiments, the medical device contact detection device provided in this embodiment of the invention, wherein the model solving module is specifically used for:

[0124] The collected results are corrected based on the gravity compensation algorithm to obtain the corrected results;

[0125] Based on the correction results, the detection model is solved to obtain the three-dimensional coordinates.

[0126] Based on the above embodiments, the medical device contact detection device provided in this embodiment of the invention, wherein the contact detection module is specifically used for:

[0127] For any facet, if the three-dimensional coordinates of the initial contact point within the facet satisfy the coordinate constraints corresponding to the facet, then the initial contact point is determined to be the actual contact point within the facet.

[0128] Based on the above embodiments, the medical device contact detection device provided in this embodiment of the invention includes medical devices.

[0129] Specifically, the functions of each module in the medical device contact detection device provided in this embodiment of the invention correspond one-to-one with the operation flow of each step in the above method-like embodiments, and the achieved effects are also the same. For details, please refer to the above embodiments, and this will not be repeated in this embodiment of the invention.

[0130] like Figure 6 As shown, based on the above embodiments, this embodiment of the invention provides a medical device contact detection system, including: a six-dimensional force sensor 61 and the medical device contact detection device 62 provided in the above embodiments.

[0131] like Figure 7 As shown, a six-dimensional force sensor 61 is installed between the instrument 63 and its control device 66 to collect force information when the instrument 63 comes into contact with a target object, obtaining the collected results. Taking a medical ultrasound probe as an example, the instrument 63 can be connected to the six-dimensional force sensor 61 via a sensor transition plate 64, and the six-dimensional force sensor 61 can be connected to the control device 66 via a sensor connector 65. Specifically, if the instrument is a medical ultrasound probe, the control device is a surgical robot, and the six-dimensional force sensor is connected to the end flange of the surgical robot via the sensor connector.

[0132] The six-dimensional force sensor 61 is connected to the instrument and equipment contact detection device 62, which can transmit the collected results to the instrument and equipment contact detection device 62 so that the instrument and equipment contact detection device 62 can determine the three-dimensional coordinates of the actual contact points in each patch on the contact detection area.

[0133] Figure 8 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 8As shown, the electronic device may include: a processor 810, a communication interface 820, a memory 830, and a communication bus 840, wherein the processor 810, the communication interface 820, and the memory 830 communicate with each other through the communication bus 840. The processor 810 can call logical instructions in the memory 830 to execute the device contact detection method provided in the above embodiments. The method includes: acquiring a patch-based contact detection area of ​​the device, and simplifying the contact detection area into patches to obtain multiple patches of the contact detection area; the device is connected to a six-dimensional force sensor; based on the plane equations of the multiple patches in the sensor coordinate system of the six-dimensional force sensor and the torque formulas of the multiple patches in the sensor coordinate system, a detection model is established, and based on the acquisition results of the six-dimensional force sensor, the detection model is solved to obtain the three-dimensional coordinates of the initial contact points of the device within the multiple patches; based on the three-dimensional coordinates and the coordinate constraints of each point within the multiple patches in the sensor coordinate system, the actual contact points within the multiple patches are determined.

[0134] Furthermore, the logical instructions in the aforementioned memory 830 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0135] On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the device contact detection method provided in the above embodiments. The method includes: acquiring a patch-based contact detection area of ​​the device, and simplifying the contact detection area into patches to obtain multiple patches of the contact detection area; the device is connected to a six-dimensional force sensor; based on the plane equations of the multiple patches in the sensor coordinate system of the six-dimensional force sensor and the torque formulas of the multiple patches in the sensor coordinate system, establishing a detection model, and solving the detection model based on the acquisition results of the six-dimensional force sensor to obtain the three-dimensional coordinates of the initial contact points of the device in the multiple patches; and determining the actual contact points in the multiple patches based on the three-dimensional coordinates and the coordinate constraints of each point in the multiple patches in the sensor coordinate system.

[0136] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the device contact detection method provided in the above embodiments. The method includes: acquiring a patch-based contact detection area of ​​the device, and simplifying the contact detection area into patches to obtain multiple patches of the contact detection area; the device is connected to a six-dimensional force sensor; establishing a detection model based on the plane equations of the multiple patches in the sensor coordinate system of the six-dimensional force sensor and the torque formulas of the multiple patches in the sensor coordinate system; solving the detection model based on the acquisition results of the six-dimensional force sensor to obtain the three-dimensional coordinates of the initial contact points of the device within the multiple patches; and determining the actual contact points within the multiple patches based on the three-dimensional coordinates and the coordinate constraints of each point within the multiple patches in the sensor coordinate system.

[0137] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0138] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0139] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for detecting contact points of medical devices, characterized in that, include: The contact detection area of ​​the instrument is obtained by simplifying the contact detection area into multiple patches. The instrument is connected to a six-dimensional force sensor; Based on the plane equations of the multiple facets in the sensor coordinate system of the six-dimensional force sensor and the torque formulas of the multiple facets in the sensor coordinate system, a detection model is established, and based on the acquisition results of the six-dimensional force sensor, the detection model is solved to obtain the three-dimensional coordinates of the initial contact point of the instrument in the multiple facets. Based on the three-dimensional coordinates and the coordinate constraints of each point within the multiple facets in the sensor coordinate system, the actual contact points within the multiple facets are determined. The plane equation of the nth patch in the sensor coordinate system for: ； Where x, y, and z are the x-axis coordinates, y-axis coordinates, and z-axis coordinates in the sensor coordinate system, respectively. , , , All are constants, and n takes values ​​from 1 to N, where N is the number of patches; The detection model is as follows: ； Where k is the local torque parameter of the contact point within the nth facet. The three-dimensional contact force in the acquisition results, The three-dimensional torque in the acquired results; Based on formula (7), formula (8) is simplified to obtain formula (9): ； Simplifying formula (9) further into matrix form, we get: （10）； The detection model is solved to obtain the three-dimensional coordinates of the initial contact points of the instrument within multiple facets.

2. The method for detecting contact points of medical devices according to claim 1, characterized in that, The process of simplifying the contact detection area into multiple patches, including: Based on the edge collapse algorithm, the contact detection area is simplified into multiple patches; the cost function of the edge collapse algorithm is determined based on the length of the edges in the multiple patches and the curvature change around the removed point.

3. The method for detecting contact points of medical devices according to claim 1, characterized in that, Based on the acquisition results from the six-dimensional force sensor, the detection model is solved to obtain the three-dimensional coordinates of the initial contact point of the instrument within the multiple facets, including: The collected results are corrected based on the gravity compensation algorithm to obtain the corrected results; Based on the correction results, the detection model is solved to obtain the three-dimensional coordinates.

4. The method for detecting contact points of medical devices according to any one of claims 1-3, characterized in that, The determination of the actual contact points within the plurality of facets based on the three-dimensional coordinates and the coordinate constraints of each point within the plurality of facets in the sensor coordinate system includes: For any facet, if the three-dimensional coordinates of the initial contact point within the facet satisfy the coordinate constraints corresponding to the facet, then the initial contact point is determined to be the actual contact point within the facet.

5. The method for detecting contact points of medical devices according to any one of claims 1-3, characterized in that, The equipment includes medical devices.

6. A device for detecting contact points of medical equipment, characterized in that, include: A patch simplification module is used to acquire the patched contact detection area of ​​the instrument, and to simplify the patch of the contact detection area to obtain multiple patches of the contact detection area; the instrument is connected to a six-dimensional force sensor; The model solving module is used to establish a detection model based on the plane equations of the multiple facets in the sensor coordinate system of the six-dimensional force sensor and the torque formulas of the multiple facets in the sensor coordinate system, and to solve the detection model based on the acquisition results of the six-dimensional force sensor to obtain the three-dimensional coordinates of the initial contact point of the instrument in the multiple facets. The contact detection module is used to determine the actual contact points within the multiple facets based on the three-dimensional coordinates and the coordinate constraints of each point within the multiple facets in the sensor coordinate system. The plane equation of the nth patch in the sensor coordinate system for: ； Where x, y, and z are the x-axis coordinates, y-axis coordinates, and z-axis coordinates in the sensor coordinate system, respectively. , , , All are constants, and n takes values ​​from 1 to N, where N is the number of patches; The detection model is as follows: ； Where k is the local torque parameter of the contact point within the nth facet. The three-dimensional contact force in the acquisition results, The three-dimensional torque in the acquired results; Based on formula (7), formula (8) is simplified to obtain formula (9): ； Simplifying formula (9) further into matrix form, we get: （10）； The detection model is solved to obtain the three-dimensional coordinates of the initial contact points of the instrument within multiple facets.

7. A contact detection system for medical devices, characterized in that, include: A six-dimensional force sensor and a medical device contact detection device as described in claim 6; The six-dimensional force sensor is installed between the instrument and its control device to collect force information when the instrument comes into contact with the target object and obtain the collection results. The six-dimensional force sensor is connected to the contact detection device of the instrument.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the device contact detection method as described in any one of claims 1-5.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the device contact detection method as described in any one of claims 1-5.

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