Complex curved surface tactile scanning point position solving method, device, equipment and medium

Abstract

Embodiments of the present application provide a complex curved surface haptic scanning point pose solving method, device, equipment and medium, the method comprises: first, establishing the local orthogonal basis of the scanning area, including the initial normal n0, the current local forward vector front_current and the current local left vector left_current; then for any scanning point, the polar angle θ and the azimuth angle φ are solved according to the tangent plane direction vector t (φ) And the unit normal vector n;And according to the position of the spherical center C, the running radius r_s and the gap compensation amount Δh, the scanning point position p is calculated;Then define the tool coordinate system z axis with z_tool=-n, and obtain x_tool through the projection of the reference direction vector front_ref in the tangent plane, then y_tool is obtained through the cross multiplication and the rotation matrix R_tool is constructed;Finally, the position and the attitude are combined, and the target pose of the mechanical arm executing the scanning task is obtained.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of robotic arm pose planning technology, and in particular to a method, apparatus, device and medium for solving the pose of tactile scanning points on complex curved surfaces. Background Technology

[0002] In tactile scanning of complex curved surfaces, softness detection, and contact contour perception tasks, the end effector of a robotic arm typically needs to approach the object being measured in a direction approximately perpendicular to the local surface. If the pose of the scanning points is not properly constructed, problems such as probe tilting contact, excessive contact normal deviation, significant abrupt changes in the pose of adjacent measurement points, and unstable robotic arm execution can easily occur, thus affecting the accuracy of tactile measurements and the repeatability of scanning.

[0003] In existing methods, some schemes directly specify the end-effector orientation based solely on the scanning point position, making it difficult to balance surface normal constraints and attitude continuity. Other schemes, while able to determine the tool's z-axis direction using normal information, do not constrain the rotational degrees of freedom around the normal direction, causing the end-effector attitude to easily change abruptly between adjacent scanning points, which is not conducive to the tactile probe's stable contact with complex curved surfaces.

[0004] Especially in scanning hemispherical or partially spherical regions, if only a single normal is used to define the end-effector orientation, the tool coordinate system will still have free rotation around the normal direction, leading to probe instability, path execution jitter, and decreased data acquisition consistency. Therefore, it is necessary to propose a method for solving the end-effector pose of scanning points that has clear geometric meaning, simple parameterization, and is suitable for robot control implementation. Summary of the Invention

[0005] This invention provides a method, apparatus, device, and medium for solving the pose of tactile scanning points on complex curved surfaces. The method constructs the z-axis of the end-effector coordinate system using the local spherical normal and determines the x-axis of the tool coordinate system using reference direction projection. This further yields the orthogonal y-axis and the complete rotation matrix, ensuring that the robotic arm end-effector satisfies both normal contact requirements and has a stable pose reference during scanning. This method has low computational complexity, clear geometric meaning, and eliminates free rotation around the normal, improving the continuity, stability, and executability of the end-effector pose during scanning.

[0006] In a first aspect, embodiments of the present invention provide a method for solving the pose of tactile scanning points on complex curved surfaces, including: Step S1: Establish a local orthogonal basis for the current scan region. The local orthogonal basis includes at least the initial normal vector n0, the current local forward vector front_current, and the current local left vector left_current. The front_current and left_current lie in the local tangent plane with n0 as the normal and are orthogonal to each other. Step S2: For any scanning point, obtain the polar angle θ and azimuth angle φ corresponding to the scanning point, and calculate the tangent plane direction vector t(φ) based on the azimuth angle φ, satisfying: t(φ)=cosφ·front_current+sinφ·left_current; Step S3: Calculate the candidate normal vector n' of the scanning point based on the polar angle θ and the tangent plane direction vector t(φ), satisfying: n'=cosθ·n0+sinθ·t(φ), and normalize n' to obtain the unit normal vector n of the scanning point; Step S4: Calculate the spatial position p of the scanning point based on the ball center position C, the running radius r_s, the gap compensation amount Δh, and the unit normal vector n, satisfying: p = C + (r_s + Δh)·n; Step S5: Define the z-axis of the end-tool coordinate system as the opposite direction of the unit normal vector n, and obtain z_tool=-n; Step S6: Project the reference direction vector front_ref onto the plane with z_tool as the normal to obtain the projection vector x', which satisfies: x'=front_ref-(front_ref·z_tool)z_tool. Then normalize x' to obtain the x-axis direction x_tool of the tool coordinate system. Step S7: Construct the y-axis direction y_tool of the tool coordinate system based on the cross product of z_tool and x_tool, and perform orthogonalization on the tool coordinate system to construct the rotation matrix R_tool=[x_tool y_tool z_tool]; Step S8: Combine the spatial position p with the rotation matrix R_tool to obtain the target end pose corresponding to the scanning point.

[0007] In some embodiments, in step S3, the normalization process satisfies: n=n' / ||n'||, so that the unit normal vector n is used to characterize the local outward normal direction of the sphere at the scanning point.

[0008] In some embodiments, in step S4, the gap compensation amount Δh is a reserved gap before the tactile probe contacts the surface being measured, or a compensation amount related to at least one of the probe length, flexible layer thickness, and contact safety margin.

[0009] In some embodiments, in step S6, the free rotation of the end-tool coordinate system about the z_tool direction is eliminated by projecting the reference direction vector front_ref into a plane perpendicular to z_tool, so that the attitude change between adjacent scan points remains continuous.

[0010] In some embodiments, in step S7, the y-axis direction of the tool coordinate system satisfies: y_tool=(z_tool×x_tool) / ||z_tool×x_tool||; and further, x_tool is modified again using x_tool=(y_tool×z_tool) / ||y_tool×z_tool|| so that x_tool, y_tool and z_tool are orthogonal to each other.

[0011] In some embodiments, when the reference direction vector front_ref is parallel or approximately parallel to z_tool, such that the magnitude of the projection vector x' in step S6 is less than a preset threshold, a preset backup reference direction vector is selected and the projection calculation is repeated to obtain an effective x_tool.

[0012] In some embodiments, step S8 further includes: converting the rotation matrix R_tool into a rotation vector, Euler angle, or quaternion form used by the robotic arm controller, and combining it with the spatial position p to form control pose data [x, y, z, rx, ry, rz] or an equivalent format.

[0013] Secondly, embodiments of the present invention also provide a device for solving the pose of tactile scanning points on complex curved surfaces, which performs the method for solving the pose of tactile scanning points on complex curved surfaces as described in the first aspect. The device includes: The parameter acquisition module is used to acquire the ball center position C, running radius r_s, gap compensation amount Δh, initial normal vector n0, current local forward vector front_current, current local left vector left_current, reference direction vector front_ref, and the polar angle θ and azimuth angle φ corresponding to the scan point; The normal vector calculation module is used to calculate the unit normal vector n of the scan point based on n0, front_current, left_current, θ, and φ. The position solving module is used to solve the spatial position p of the scanning point based on the sphere center position C, the running radius r_s, the gap compensation amount Δh, and the unit normal vector n; The attitude construction module is used to construct the tool coordinate system based on the unit normal vector n and the reference direction vector front_ref, and output the target end pose of the scan point.

[0014] Thirdly, embodiments of the present invention also provide an electronic device, including: 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 computer program, it implements the method for solving the pose of complex curved surface tactile scanning points as described in the first aspect.

[0015] Fourthly, embodiments of the present invention also provide a computer-readable storage medium storing computer-executable instructions for executing the complex surface tactile scanning point pose solving method as described in the first aspect.

[0016] According to embodiments of the present invention, a method, apparatus, device, and medium for solving the pose of tactile scanning points on complex curved surfaces are provided. The method for solving the pose of tactile scanning points on complex curved surfaces includes: establishing a local orthogonal basis for the current scanning region. The local orthogonal basis includes at least an initial normal vector n0, a current local forward vector front_current, and a current local left vector left_current. Specifically, front_current... The left_current and the right_current lie in the local tangent plane with n0 as the normal and are orthogonal to each other; for any scanning point, obtain the polar angle θ and azimuth angle φ corresponding to the scanning point, and calculate the tangent plane direction vector t(φ) based on the azimuth angle φ, satisfying: t(φ)=cosφ·front_current+sinφ·left_current; calculate the candidate normal vector n' of the scanning point based on the polar angle θ and the tangent plane direction vector t(φ), satisfying: n'=cosθ·n0+sinθ·t(φ), and normalize n' to obtain the unit normal vector n of the scanning point; calculate the empty space of the scanning point based on the sphere center position C, the running radius r_s, the gap compensation amount Δh, and the unit normal vector n. The spatial position p satisfies: p = C + (r_s + Δh)·n; the z-axis of the end-effector coordinate system is defined as the opposite direction of the unit normal vector n, resulting in z_tool = -n; the reference direction vector front_ref is projected onto the plane with z_tool as the normal, resulting in the projection vector x', satisfying: x' = front_ref - (front_ref·z_tool)z_tool, and x' is normalized to obtain the x-axis direction x_tool of the tool coordinate system; the y-axis direction y_tool of the tool coordinate system is constructed based on the cross product of z_tool and x_tool, and the tool coordinate system is orthogonalized to construct the rotation matrix R_tool = [x_tool y_tool z_tool]; the spatial position p is combined with the rotation matrix R_tool to obtain the target end-effector pose corresponding to the scan point.Based on this, the complex curved surface tactile scanning point pose solution method of this invention can be applied to any curved surface tactile scanning scenario. First, a local orthogonal basis for the scanning area is established, including the initial normal vector n0, the current local forward vector front_current, and the current local left vector left_current. Then, for any scanning point, the tangent plane direction vector t(φ) and the unit normal vector n are solved based on the polar angle θ and the azimuth angle φ. On this basis, the scanning point position p is calculated based on the sphere center position C, the running radius r_s, and the gap compensation amount Δh. Then, the tool coordinate system z-axis is defined with z_tool=-n, and x_tool is obtained by projecting the reference direction vector front_ref into the tangent plane. Then, y_tool is obtained by cross product and the rotation matrix R_tool is constructed. Finally, the position and attitude are combined to obtain the target pose of the robotic arm performing the scanning task.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects: (1) For any curved surface, the scanning point normal can be directly constructed using the local spherical parameterization relationship. The calculation process is simple and easy to implement in engineering. (2) Align the z-axis of the tool coordinate system with the scanning point normal in the opposite direction so that the tactile probe can approach the surface along the local normal direction and improve contact stability; (3) By using the projection of the reference direction vector onto the tangent plane to constrain the x-axis, the attitude free rotation around the normal direction is effectively eliminated, and the attitude continuity between adjacent measurement points is improved. (4) A complete coordinate base is constructed by using cross product and re-orthogonalization to improve the numerical stability of the rotation matrix and facilitate the output to a pose format that can be recognized by the robotic arm controller. Attached Figure Description

[0018] Figure 1 This is a flowchart of a method for solving the pose of tactile scanning points on complex curved surfaces, provided in one embodiment of the present invention. Figure 2 This is a schematic diagram illustrating the solution of the spherical normal at a scanning point according to an embodiment of the present invention; Figure 3 This is a schematic diagram illustrating the solution of the spatial position of the scanning point according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the end-effector coordinate system construction provided in one embodiment of the present invention; Figure 5 This is a flowchart of the scanning point target pose output according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of a complex curved surface tactile scanning point pose solving device provided in an embodiment of the present invention; Figure 7 This is a schematic diagram of an electronic device provided in one embodiment of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0020] It should be noted that although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the device or the order in the flowchart. The terms "first," "second," etc., in the specification, claims, and the following drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0021] In this embodiment of the invention, the terms "furthermore," "exemplarily," or "optionally" are used as examples, illustrations, or descriptions and should not be construed as being more preferred or advantageous than other embodiments or designs. The use of the terms "furthermore," "exemplarily," or "optionally" is intended to present the relevant concepts in a specific manner.

[0022] To facilitate a more convenient description of the working principle of the embodiments of the present invention, the following introduction of relevant technical scenarios is given first.

[0023] In tactile scanning of complex curved surfaces, softness detection, and contact contour perception tasks, the end effector of a robotic arm typically needs to approach the object being measured in a direction approximately perpendicular to the local surface. If the pose of the scanning points is not properly constructed, problems such as probe tilting contact, excessive contact normal deviation, significant abrupt changes in the pose of adjacent measurement points, and unstable robotic arm execution can easily occur, thus affecting the accuracy of tactile measurements and the repeatability of scanning.

[0024] In existing methods, some schemes directly specify the end-effector orientation based solely on the scanning point position, making it difficult to balance surface normal constraints and attitude continuity. Other schemes, while able to determine the tool's z-axis direction using normal information, do not constrain the rotational degrees of freedom around the normal direction, causing the end-effector attitude to easily change abruptly between adjacent scanning points, which is not conducive to the tactile probe's stable contact with complex curved surfaces.

[0025] Especially in scanning hemispherical or partially spherical regions, if only a single normal is used to define the end-effector orientation, the tool coordinate system will still have free rotation around the normal direction, leading to probe instability, path execution jitter, and decreased data acquisition consistency. Therefore, it is necessary to propose a method for solving the end-effector pose of scanning points that has clear geometric meaning, simple parameterization, and is suitable for robot control implementation.

[0026] Based on this, the present invention provides a method, apparatus, device, and medium for solving the pose of tactile scanning points on complex curved surfaces. The method for solving the pose of tactile scanning points on complex curved surfaces includes: establishing a local orthogonal basis for the current scanning region, wherein the local orthogonal basis includes at least an initial normal vector n0, a current local forward vector front_current, and a current local left vector left_current, wherein front_current... The left_current and the right_current lie in the local tangent plane with n0 as the normal and are orthogonal to each other; for any scanning point, obtain the polar angle θ and azimuth angle φ corresponding to the scanning point, and calculate the tangent plane direction vector t(φ) based on the azimuth angle φ, satisfying: t(φ)=cosφ·front_current+sinφ·left_current; calculate the candidate normal vector n' of the scanning point based on the polar angle θ and the tangent plane direction vector t(φ), satisfying: n'=cosθ·n0+sinθ·t(φ), and normalize n' to obtain the unit normal vector n of the scanning point; calculate the empty space of the scanning point based on the sphere center position C, the running radius r_s, the gap compensation amount Δh, and the unit normal vector n. The spatial position p satisfies: p = C + (r_s + Δh)·n; the z-axis of the end-effector coordinate system is defined as the opposite direction of the unit normal vector n, resulting in z_tool = -n; the reference direction vector front_ref is projected onto the plane with z_tool as the normal, resulting in the projection vector x', satisfying: x' = front_ref - (front_ref·z_tool)z_tool, and x' is normalized to obtain the x-axis direction x_tool of the tool coordinate system; the y-axis direction y_tool of the tool coordinate system is constructed based on the cross product of z_tool and x_tool, and the tool coordinate system is orthogonalized to construct the rotation matrix R_tool = [x_tool y_tool z_tool]; the spatial position p is combined with the rotation matrix R_tool to obtain the target end-effector pose corresponding to the scan point.Based on this, the pose calculation method for complex curved surface tactile scanning points in this invention can be applied to any curved surface tactile scanning scenario. First, a local orthogonal basis for the scanning region is established, including the initial normal vector n0, the current local forward vector front_current, and the current local left vector left_current. Then, for any scanning point, the tangent plane direction vector t(φ) and the unit normal vector n are solved based on the polar angle θ and azimuth angle φ. On this basis, the scanning point position p is calculated based on the sphere center position C, the running radius r_s, and the gap compensation amount Δh. Next, the tool coordinate system z-axis is defined with z_tool = -n, and x_tool is obtained by projecting the reference direction vector front_ref onto the tangent plane. Then, y_tool is obtained through the cross product, and a rotation matrix R_tool is constructed. Finally, the position and attitude are combined to obtain the target pose for the robotic arm to perform the scanning task. This method has low computational complexity, clear geometric meaning, and can eliminate free rotation of the attitude around the normal, improving the continuity, stability, and executability of the end-effector attitude during the scanning process.

[0027] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0028] like Figure 1 As shown, Figure 1 This is a flowchart of a method for solving the pose of tactile scanning points on complex curved surfaces, provided by an embodiment of the present invention. The method for solving the pose of tactile scanning points on complex curved surfaces may include, but is not limited to, steps S1 to S8.

[0029] Step S1: Establish a local orthogonal basis for the current scanned region. The local orthogonal basis includes at least the initial normal vector n0, the current local forward vector front_current, and the current local left vector left_current. The front_current and left_current lie in the local tangent plane with n0 as the normal and are orthogonal to each other. Step S2: For any scanning point, obtain the polar angle θ and azimuth angle φ corresponding to the scanning point, and calculate the tangent plane direction vector t(φ) based on the azimuth angle φ, satisfying: t(φ)=cosφ·front_current+sinφ·left_current; Step S3: Calculate the candidate normal vector n' of the scanning point based on the polar angle θ and the tangent plane direction vector t(φ), satisfying: n'=cosθ·n0+sinθ·t(φ), and normalize n' to obtain the unit normal vector n of the scanning point; Step S4: Based on the ball center position C, running radius r_s, gap compensation amount Δh, and unit normal vector n, calculate the spatial position p of the scanning point, satisfying: p=C+(r_s+Δh)·n; Step S5: Define the z-axis of the end-tool coordinate system as the opposite direction of the unit normal vector n, and obtain z_tool=-n; Step S6: Project the reference direction vector front_ref onto the plane with z_tool as the normal to obtain the projection vector x', which satisfies: x'=front_ref-(front_ref·z_tool)z_tool. Then normalize x' to obtain the x-axis direction x_tool of the tool coordinate system. Step S7: Construct the y-axis direction y_tool of the tool coordinate system based on the cross product of z_tool and x_tool, and perform orthogonalization on the tool coordinate system to construct the rotation matrix R_tool=[x_tool y_tool z_tool]; Step S8: Combine the spatial position p with the rotation matrix R_tool to obtain the target end pose corresponding to the scanning point.

[0030] It is understood that the complex surface tactile scanning point pose solution method of the present invention is applicable to any surface tactile scanning scenario, including but not limited to robots performing tactile scanning tasks on hemispherical surfaces, local spherical approximation regions, and other surface scanning scenarios that can be expressed using local spherical parameterization, and is used to generate target poses that meet the normal contact requirements for tactile probes or other contact end effectors.

[0031] Understandably, the complex curved surface tactile scanning point pose solution method of the present invention first calculates the spherical normal vector n at the scanning point based on the initial normal vector n0 and the orthogonal base directions front_current and left_current of the local tangent plane, combined with the scanning parameters θ and φ; then, the spatial position p of the scanning point is obtained based on the sphere center C, the running radius r_s, and the gap compensation amount Δh. Subsequently, the tool coordinate system z-axis is constrained with z_tool=-n, so that the probe approaches the measured surface along the opposite direction of the local surface normal; and the reference direction front_ref is projected into the tangent plane with z_tool as the normal to obtain the tool coordinate system x-axis, and then the y-axis is obtained by cross product and the coordinate base is orthogonalized to construct the rotation matrix R_tool=[x_tool y_tool z_tool]. Finally, the position p and the rotation matrix R_tool are combined to obtain the target pose of the scanning point, which can be further converted into the rotation vector form required by the robotic arm controller. This method has low computational cost and clear geometric meaning. It can eliminate free rotation of the posture around the normal and improve the continuity, stability and executability of the end posture during the scanning process.

[0032] In one embodiment, the region to be measured is approximated as a local spherical region. First, the center position C of the sphere is determined during the calibration phase, and a local orthogonal basis is established at the scanning start point, where n0 represents the normal vector at the start point, and front_current and left_current are both located in the tangent plane with n0 as the normal, and front_current and left_current are mutually orthogonal.

[0033] like Figure 2 As shown, for any scanning point, its position on the local sphere is described by two parameters: the polar angle θ and the azimuth angle φ. Here, θ characterizes the deflection of the scanning point relative to the initial normal n0, and φ characterizes the direction of the scanning point within the local tangent plane. Based on the azimuth angle φ, the tangent plane direction vector t(φ) is constructed: t(φ)=cosφ·front_current+sinφ·left_current n' = cosθ·n0 + sinθ·t(φ) n=n' / ||n'|| Here, n' is a candidate normal vector for the scan point, which is normalized to obtain the unit normal vector n. This unit normal vector n can be used to characterize the outward normal direction of the local sphere corresponding to the scan point.

[0034] like Figure 3 As shown, after obtaining the unit normal vector n, the spatial position p of the scanning point is calculated based on the sphere center position C, the running radius r_s, and the gap compensation amount Δh: p = C + (r_s + Δh)·n Where r_s is the operating radius corresponding to the current scanning task, and Δh is the additional gap compensation amount before contact. When the system adopts a gapless approach strategy, Δh can be taken as 0, in which case the scanning point position degenerates to p = C + r_s·n.

[0035] To ensure the tactile probe approaches the surface being measured along the local surface normal direction, the z-axis direction of the end-effector coordinate system is defined as the opposite direction of the unit normal vector n, i.e.: z_tool=-n Since the complete pose cannot be uniquely determined solely by z_tool, the end-effector coordinate system also has a degree of freedom for rotation around z_tool. Therefore, as... Figure 4 As shown, this embodiment introduces a reference direction vector front_ref and projects it onto a plane with z_tool as the normal, thereby constructing the tool coordinate system x-axis: x'=front_ref-(front_ref·z_tool)z_tool x_tool=x' / ||x'|| Through the above projection operation, the tool coordinate system can maintain a stable forward reference while satisfying the z-axis normal constraint, thereby reducing the attitude jump caused by free rotation between adjacent scan points.

[0036] After obtaining x_tool and z_tool, the y-axis of the tool coordinate system is completed using the cross product relationship, and the tool coordinate system is orthogonalized again to obtain: y_tool=(z_tool×x_tool) / ||z_tool×x_tool|| x_tool=(y_tool×z_tool) / ||y_tool×z_tool|| After the above processing, the three axis vectors of the tool coordinate system are pairwise orthogonal and are unit vectors, thus constructing the rotation matrix: R_tool=[x_tooly_toolz_tool] Finally, the spatial position p of the scan point is combined with the rotation matrix R_tool to obtain the end pose T of the target at the scan point: T=[p, R_tool] like Figure 5 As shown, in robot control implementation, the rotation matrix R_tool can be further converted into rotation vector, quaternion or Euler angle expression, and encapsulated together with the position vector p into target pose data that the controller can recognize, such as [x,y,z,rx,ry,rz].

[0037] In a preferred embodiment, when the reference direction vector front_ref is parallel or approximately parallel to z_tool, the magnitude of the projection vector x' may approach zero. In this case, a spare reference direction vector can be preset, and the projection step can be re-executed using this spare reference direction vector instead of front_ref to ensure that the x-axis of the tool coordinate system can be stably solved.

[0038] The method provided by this invention can be directly used for scanning point pose planning in complex curved surface tactile scanning systems, and is particularly suitable for scanning tasks involving hemispherical surfaces, approximate spherical regions, and other areas requiring the maintenance of normal contact and pose continuity. Compared to schemes that only specify the normal or only specify the position, this invention can simultaneously consider contact direction, pose uniqueness, and robot execution stability, thereby improving tactile sampling quality and scanning reconstruction results.

[0039] Based on this, compared with the prior art, the present invention has at least the following beneficial effects: (1) For any curved surface, the scanning point normal can be directly constructed using the local spherical parameterization relationship. The calculation process is simple and easy to implement in engineering. (2) Align the z-axis of the tool coordinate system with the scanning point normal in the opposite direction so that the tactile probe can approach the surface along the local normal direction and improve contact stability; (3) By using the projection of the reference direction vector onto the tangent plane to constrain the x-axis, the attitude free rotation around the normal direction is effectively eliminated, and the attitude continuity between adjacent measurement points is improved. (4) A complete coordinate base is constructed by using cross product and re-orthogonalization to improve the numerical stability of the rotation matrix and facilitate the output to a pose format that can be recognized by the robotic arm controller.

[0040] In addition, such as Figure 6 As shown, one embodiment of the present invention also discloses a device for solving the pose of tactile scanning points on complex curved surfaces, which performs the method for solving the pose of tactile scanning points on complex curved surfaces as described in any of the preceding embodiments. The device includes: The parameter acquisition module 110 is used to acquire the ball center position C, running radius r_s, gap compensation amount Δh, initial normal vector n0, current local forward vector front_current, current local left vector left_current, reference direction vector front_ref, and polar angle θ and azimuth angle φ corresponding to the scan point; Normal vector solving module 120 is used to solve for the unit normal vector n of the scan point based on n0, front_current, left_current, θ and φ; The position solving module 130 is used to solve the spatial position p of the scanning point based on the sphere center position C, the running radius r_s, the gap compensation amount Δh, and the unit normal vector n; The attitude construction module 140 is used to construct the tool coordinate system based on the unit normal vector n and the reference direction vector front_ref, and output the target end pose of the scan point.

[0041] The complex surface tactile scanning point pose solving device of the present invention is used to execute the complex surface tactile scanning point pose solving method in the above embodiments. Its specific processing is the same as the complex surface tactile scanning point pose solving method in the above embodiments, and will not be described in detail here.

[0042] In addition, such as Figure 7As shown, an embodiment of the present invention also discloses an electronic device, including: at least one processor 210; at least one memory 220 for storing at least one program; when the at least one program is executed by at least one processor 210, it implements the complex surface tactile scanning point pose solution method as in any of the preceding embodiments.

[0043] In addition, one embodiment of the present invention discloses a computer-readable storage medium storing computer-executable instructions for performing the complex surface tactile scanning point pose solving method as described in any of the preceding embodiments.

[0044] The system architecture and application scenarios described in the embodiments of this invention are for the purpose of more clearly illustrating the technical solutions of the embodiments of this invention, and do not constitute a limitation on the technical solutions provided by the embodiments of this invention. As those skilled in the art will know, with the evolution of system architecture and the emergence of new application scenarios, the technical solutions provided by the embodiments of this invention are also applicable to similar technical problems.

[0045] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0046] In hardware implementations, the division between functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software may be distributed on a computer-readable medium, which may include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0047] The terms “component,” “module,” “system,” etc., used in this specification are used to refer to computer-related entities, hardware, firmware, combinations of hardware and software, software, or software in execution. For example, a component can be, but is not limited to, a process running on a processor, a processor, an object, an executable file, an execution thread, a program, or a computer. As illustrated, applications running on computing devices and computing devices can both be components. One or more components may reside in a process or execution thread, and components may be located on a single computer or distributed among two or more computers. Furthermore, these components can be executed from various computer-readable media on which various data structures are stored. Components can communicate, for example, via local or remote processes based on signals having one or more data packets (e.g., data from two components interacting with another component between a local system, a distributed system, or a network, such as the Internet interacting with other systems via signals).

Claims

1. A method for solving the pose of tactile scanning points on complex curved surfaces, characterized in that, Includes the following steps: Step S1: Establish a local orthogonal basis for the current scan region. The local orthogonal basis includes at least the initial normal vector n0, the current local forward vector front_current, and the current local left vector left_current. The front_current and left_current lie in the local tangent plane with n0 as the normal and are orthogonal to each other. Step S2: For any scanning point, obtain the polar angle θ and azimuth angle φ corresponding to the scanning point, and calculate the tangent plane direction vector t(φ) based on the azimuth angle φ, satisfying: t(φ)=cosφ·front_current+sinφ·left_current; Step S3: Calculate the candidate normal vector n' of the scanning point based on the polar angle θ and the tangent plane direction vector t(φ), satisfying: n'=cosθ·n0+sinθ·t(φ), and normalize n' to obtain the unit normal vector n of the scanning point; Step S4: Calculate the spatial position p of the scanning point based on the ball center position C, the running radius r_s, the gap compensation amount Δh, and the unit normal vector n, satisfying: p = C + (r_s + Δh)·n; Step S5: Define the z-axis of the end-tool coordinate system as the opposite direction of the unit normal vector n, and obtain z_tool=-n; Step S6: Project the reference direction vector front_ref onto the plane with z_tool as the normal to obtain the projection vector x', which satisfies: x'=front_ref-(front_ref·z_tool)z_tool. Then normalize x' to obtain the x-axis direction x_tool of the tool coordinate system. Step S7: Construct the y-axis direction y_tool of the tool coordinate system based on the cross product of z_tool and x_tool, and perform orthogonalization on the tool coordinate system to construct the rotation matrix R_tool=[x_tool y_tool z_tool]; Step S8: Combine the spatial position p with the rotation matrix R_tool to obtain the target end pose corresponding to the scanning point.

2. The method for solving the pose of tactile scanning points on complex curved surfaces according to claim 1, characterized in that, In step S3, the normalization process satisfies: n=n' / ||n'||, so that the unit normal vector n is used to characterize the local outward normal direction of the sphere at the scanning point.

3. The method for solving the pose of tactile scanning points on complex curved surfaces according to claim 1, characterized in that, In step S4, the gap compensation amount Δh is the reserved gap before the tactile probe contacts the surface being measured, or it is a compensation amount related to at least one of the probe length, flexible layer thickness, and contact safety margin.

4. The method for solving the pose of tactile scanning points on complex curved surfaces according to claim 1, characterized in that, In step S6, the free rotation of the end-tool coordinate system around the z_tool direction is eliminated by projecting the reference direction vector front_ref onto a plane perpendicular to z_tool, thus maintaining the continuity of attitude changes between adjacent scan points.

5. The method for solving the pose of tactile scanning points on complex curved surfaces according to claim 1, characterized in that, In step S7, the y-axis direction of the tool coordinate system satisfies: y_tool=(z_tool×x_tool) / ||z_tool×x_tool||; and further, x_tool is modified again using x_tool=(y_tool×z_tool) / ||y_tool×z_tool|| so that x_tool, y_tool and z_tool are orthogonal to each other.

6. The method for solving the pose of tactile scanning points on complex curved surfaces according to claim 1, characterized in that, When the reference direction vector front_ref is parallel or approximately parallel to z_tool, such that the magnitude of the projection vector x' in step S6 is less than a preset threshold, a preset backup reference direction vector is selected and the projection calculation is repeated to obtain an effective x_tool.

7. The method for solving the pose of tactile scanning points on complex curved surfaces according to claim 1, characterized in that, Step S8 further includes: converting the rotation matrix R_tool into a rotation vector, Euler angle, or quaternion form used by the robotic arm controller, and combining it with the spatial position p to form control pose data [x, y, z, rx, ry, rz] or an equivalent format.

8. A device for solving the pose of tactile scanning points on complex curved surfaces, characterized in that, The apparatus for performing the complex curved surface tactile scanning point pose determination method as described in any one of claims 1 to 7 includes: The parameter acquisition module is used to acquire the ball center position C, running radius r_s, gap compensation amount Δh, initial normal vector n0, current local forward vector front_current, current local left vector left_current, reference direction vector front_ref, and the polar angle θ and azimuth angle φ corresponding to the scan point; The normal vector calculation module is used to calculate the unit normal vector n of the scan point based on n0, front_current, left_current, θ, and φ. The position solving module is used to solve the spatial position p of the scanning point based on the sphere center position C, the running radius r_s, the gap compensation amount Δh, and the unit normal vector n; The attitude construction module is used to construct the tool coordinate system based on the unit normal vector n and the reference direction vector front_ref, and output the target end pose of the scan point.

9. 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 computer program, it implements the method for solving the pose of complex curved surface tactile scanning points as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing computer-executable instructions for performing the method for solving the pose of tactile scanning points on complex curved surfaces as described in any one of claims 1 to 7.

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