Pipeline inner circle grinding device and grinding method

Abstract

The invention discloses a pipeline inner circle grinding device and method, and belongs to the technical field of pipeline machining, the pipeline inner circle grinding device comprises a center rotating shaft, a reducing mechanism and a wheel type grinding machine, the reducing mechanism comprises telescopic components arranged in the circumferential direction of the center rotating shaft, straight lines where the telescopic directions of every two adjacent telescopic components are located intersect, and all intersection points can form a regular polygon; the center rotating shaft is provided with a regular polygon, the regular polygon is provided with an inscribed circle coaxially arranged with the center rotating shaft, the extension directions of all the telescopic components deflect clockwise or anticlockwise of the inscribed circle, the telescopic end of each telescopic component is provided with a wheel type grinding machine, and the axis of a grinding wheel of each wheel type grinding machine is parallel to the axis of the center rotating shaft. The multiple wheel type grinding machines conduct synchronous grinding, the grinding efficiency can be improved, the eccentric degree of the center shaft can be reduced, the situation that local grinding is too deep (over-cutting) or too shallow (under-grinding) is avoided, the diameter changing function of the grinding range can be achieved under the action of the diameter changing mechanism, and the requirement for grinding the inner circles of pipelines with different diameters is met.

Description

Technical Field

[0001] This invention relates to the field of pipe processing technology, and in particular to a pipe inner circle grinding device and grinding method. Background Technology

[0002] In the processing of metal pipes, continuous and uniform grinding of the inner wall to remove oxide layers, burrs, or improve surface finish is an important step. Currently, for grinding the inner walls of metal pipes of a certain length, cantilever grinding devices are commonly used. This device typically inserts a cantilever rod equipped with a grinding head (such as a grinding wheel or whetstone) into the pipe. By driving the cantilever rod to rotate around its own axis, the grinding wheel rotates around the inner wall of the metal pipe for one revolution, thus grinding one section. After completing the grinding of one section, the device moves along the pipe axis to grind the next section, repeating this process until the entire inner wall of the pipe is processed.

[0003] However, this traditional cantilever grinding method has obvious drawbacks: 1. Low grinding efficiency: This process is essentially a sequential "point-line-surface" processing procedure. Grinding each section requires the cantilever to rotate a full circle, and the grinding is done sequentially between sections, making parallel operation impossible. For long pipes, this point-by-point scanning processing path is long and time-consuming, resulting in low overall grinding efficiency.

[0004] 2. Poor Grinding Accuracy and Consistency: Due to the slender structure of the cantilever rod, it is prone to bending deformation and vibration when rotating at high speed and bearing the reaction force of grinding. This instability leads to uneven pressure of the grinding wheel on the pipe wall, which can easily cause localized problems of excessive grinding (over-cutting) or insufficient grinding (under-grinding) on ​​the inner wall surface. It is difficult to ensure the uniformity and dimensional accuracy of grinding the entire inner wall surface, making product quality difficult to control.

[0005] Therefore, there is an urgent need for a new technical solution that can efficiently and accurately complete the continuous grinding of the inner wall of metal tubes. Summary of the Invention

[0006] The purpose of this invention is to solve the above-mentioned technical problems and provide a device and method for grinding the inner circle of a pipe. Multiple wheel-type grinding machines are arranged around the central rotating shaft to grind simultaneously, which can improve grinding efficiency and reduce the eccentricity of the central shaft, ensuring that the pressure of each grinding wheel on the pipe wall is uniform, reducing the problem of local grinding that is too deep (over-cut) or too shallow (under-grinded) on the inner wall surface of the pipe, improving grinding uniformity and dimensional accuracy. Moreover, the diameter-changing mechanism can adapt and adjust according to the actual inner diameter of the pipe to meet the grinding needs of pipes with different diameters.

[0007] To achieve the above objectives, the present invention provides the following solution: The present invention discloses a pipe inner circle grinding device, including a central rotating shaft, a diameter changing mechanism, and a wheel grinding machine. The diameter changing mechanism includes telescopic members arranged circumferentially along the central rotating shaft. The straight lines containing the telescopic directions of two adjacent telescopic members intersect to form an intersection point. All intersection points can form a regular polygon. The regular polygon has an inscribed circle coaxially arranged with the central rotating shaft. The extension direction of all telescopic members deflects clockwise or counterclockwise along the inscribed circle. The telescopic end of each telescopic member is equipped with the wheel grinding machine. The axis of the grinding wheel of the wheel grinding machine is parallel to the axis of the central rotating shaft.

[0008] Preferably, each of the telescopic components has a wheel-type grinder installed at its telescopic end, and the grinding wheels of each wheel-type grinder are arranged on the same plane.

[0009] Preferably, the variable diameter mechanism includes three telescopic components.

[0010] Preferably, the wheel grinder is equipped with a cooling nozzle, which is used to spray cooling gas onto the grinding wheel.

[0011] Preferably, the telescopic component includes a central shaft mounting plate, a guide shaft, a guide shaft adapter plate, a cylinder, a cylinder adapter plate, and a grinder mounting plate. The central shaft mounting plate is fixedly connected to the central rotating shaft. The guide shaft adapter plate is fixedly connected to the central shaft mounting plate. A guide shaft sleeve is provided on the guide shaft adapter plate. The guide shaft is slidably connected to the guide shaft sleeve. The cylinder body is fixedly connected to the guide shaft sleeve through the cylinder adapter plate. The piston rod of the cylinder is arranged parallel to the guide shaft sleeve. The grinder mounting plate is fixedly connected to the piston rod of the cylinder and the guide shaft. The wheel grinder is fixedly mounted on the cylinder. The cylinder is connected to the air supply equipment through a proportional valve.

[0012] Preferably, one of the central shaft mounting plates is equipped with a remote controller capable of remotely receiving control signals, and the proportional valve and the wheel grinder are both electrically connected to the remote controller.

[0013] Preferably, the wheel grinder includes a drive motor, a grinding wheel, a handle, a threaded end cap, a floating spherical bearing, and a support spring. The end of the motor shaft of the drive motor is provided with a drive groove. One end of the handle is fixedly connected to the axle of the grinding wheel, and the other end of the handle is installed in the drive groove through the floating spherical bearing. The end of the handle located in the drive groove is provided with a limiting shaft, the diameter of which is larger than that of the handle. The threaded end cap is threaded to the end of the motor shaft. The threaded end cap and the limiting shaft clamp the floating spherical bearing in the middle. The limiting shaft is provided with a spring groove, one end of which is installed in the spring groove, and the other end of which abuts against the groove wall of the drive groove.

[0014] This invention also discloses a method for grinding the inner circle of a pipe, which uses the aforementioned pipe inner circle grinding device; including the following steps: S1. The central shaft is rotated inside the pipe by an external drive; S2. Control the extension of each telescopic component of the diameter-changing mechanism until the grinding wheel of each wheel grinder contacts the pipe wall. During the extension of the telescopic components, start the wheel grinder to make the grinding wheel rotate and cool the grinding wheel. S3. After grinding is completed, control the retraction of each telescopic component to drive the grinding wheels of each wheel grinder back to their initial state. During the retraction of the telescopic components, the wheel grinder is turned off and the cooling of the grinding wheels is stopped.

[0015] Preferably, in step S2, when the grinding wheel contacts the pipe wall, the power of the drive motor of the wheel grinder begins to increase. When the power increases to a set value, the proportional valve in the telescopic component is controlled to maintain the pressure balance between the rod chamber and the rodless chamber of the cylinder, thereby achieving constant power control of the drive motor. The grinding wheel floats within 5° in the diameter direction to adapt to the unevenness of the pipe wall. In step S3, after grinding is completed, the proportional valve in the telescopic component is controlled to adjust the cylinder so that the pressure in the rod chamber of the cylinder is higher than the pressure in the rodless chamber, thereby controlling the piston rod of the cylinder to retract.

[0016] Preferably, an algorithm is used to control the expansion and contraction of the telescopic component. The algorithm's workflow is as follows: S1. Convert the input point cloud data of the area to be polished from a 3D coordinate system to a cylindrical coordinate system, first converting the axial direction... Geometric centering of each cross section The determination; then for any point Define cylindrical coordinates as , where the radius ,angle ; S2. Based on the pitch of the wheel grinder, the cylindrical coordinate system is helically mapped to a time-domain coordinate system that can be used for grinding control. The mechanical structure obtains the angular velocity of the grinding unit feed. Axial feed rate Initial phase Initial axial position Angle distribution of the grinding wheel Phase mapping is The grinding curve is mapped to To ensure the consistency of time scale in time-domain data; S3. Sample and discretize the time-domain information. By inputting the axial position, the required grinding amount, the grinding wheel position distribution, and the maximum allowable normal force of a single grinding wheel. Set the weight of grinding amount allocation for a single grinding wheel. Perform a share of liability calculation to ensure: ; in Furthermore, constraints need to be set to avoid circumferential and axial stripes. ; Let be the radius of the contact wheel; to avoid single-end overload, based on the conservation of belt volume and the upper limit of normal force, define the first... Head sampling in the axial direction The upper bound of the load-bearing removal capacity is: ; Based on this allocation, the following conditions are met: ; For the objective function chosen as clock priority + load balancing: ; The required parameters can be obtained by applying the above conditions. , Enable command for grinding wheel; S4. Axial-grinding amount distribution results Convert to the first Grinding wheel at sampling position The target normal force and cylinder displacement reference are used as the sole input to the execution layer. The target normal force, obtained by removing the thickness, is transformed into the following relationship: ; in, The pre-calibrated material removal rate coefficient; S5, Target Normal Force The displacement is converted into a traceable reference for the actuator, and a uniform hard upper bound is set in subsequent shaping. A calibrated quasi-static contact model is adopted: the cylinder displacement is mapped to the normal compression through the mechanism's geometric gain. The overall equivalent stiffness characterizes the combined elasticity of the cylinder, mechanism, grinding wheel, and workpiece, while considering assembly zero bias and anti-preload; its linear relationship is: ; in To ensure that the direction opposite to the propulsion is positive, the target force is inversely solved as a displacement reference for subsequent shaping: ; in, To achieve zero-biased no-load assembly of the baseline, This is the geometric amplification factor for the cylinder displacement-normal displacement gain; simultaneously, the upper limit of the system force is uniformly mapped to a hard upper limit of displacement. ; Then, a quasi-static push-pressure regression was performed on a standard pipeline. , , ; Combined with known preload At this point, and Closed-form determination; S6. Establish the source and connection relationship of the execution upper limit. The geometric travel upper limit and the force limit → displacement limit jointly determine the allowable displacement upper limit of this sampling point: ; This ensures that subsequent shaping always operates within the dual boundaries of reachable stroke and unexceeded force. Then, the actuator's velocity, acceleration, and Jerk constraints are transformed into discrete difference boundaries to avoid spikes and resonances; equivalently, this is expressed as upper bounds on first-, second-, and third-order differences. , , At each sampling step, the target curve is filtered using cascaded amplitude-limited integrals. The executable reference is as follows: First, limit the jerk to obtain the acceleration, then limit the acceleration to obtain the velocity, and finally integrate to obtain the displacement and trim it to the upper bound, where: , , , ; in Initialization is possible , , ;exist Sections use small Achieve soft entry and exit; then limit the rate of change of force, which can set an upper limit on the force slope. Mapped to the upper limit of the rate of change of displacement, for further suppression of force impact: ; To maintain consistency with the aforementioned time delay modeling, sample advance is adopted. Discrete feedforward compensation is performed in a manner that... To round to the nearest whole number; therefore, the parameter compensation is: , ; S7, for sampling periods of Force error is When there is no power to sense the force error, it is estimated using force estimation. The error is passed through virtual mechanical impedance. Inverse calculation for displacement correction, , , The minimum structure is selected to determine the discrete implementation of response speed and damping. ; Then, according to the upper bound of each head. The trimming process ensures that the force limit → displacement limit constraint and the travel constraint are both uniformly applied: ; Next, we address instantaneous saturation and modal excitation; we convert the clipped displacement error back to the velocity state, ensuring a smooth retreat from the boundary in the next step and avoiding secondary overshoot due to saturation accumulation. ; in The boundary values ​​for this hit are the upper or lower bounds. Backfeedback only takes effect when pruning occurs. ; Then, using the two formulas above, the determined acceleration and Jerk upper limit are directly projected onto the discrete increments, ensuring... The changes in velocity and acceleration will not exceed A shape reference envelope is used to avoid exciting mechanism resonance and reduce surface ripple; S8, In the generation of impedance superposition and limited recharge Subsequently, to close the force loop under no-sensing conditions, a low-cost force estimation method equivalent to the current of the drive motor 301 is adopted, and compared with the force error. Seamless connection, that is use The smallest feasible form of the alternative is: in This is a combined coefficient for the motor force constant and transmission efficiency. This is the no-load current. , Characterizing the static / viscous friction terms respectively, This formula maps the measurable quantities on the drive side to a normal force estimate. The measurable quantities on the drive side include current and velocity, which are used to calculate: ; This allows for the closure of the external force loop without the need for additional force sensors; explicit deduction of the friction term reduces force deviation caused by low-speed stick-slip and suppresses command jitter caused by estimation noise; in position measurement Superimposed first-order perturbation observations (ESO) Make minor corrections to enhance robustness under load transition scenarios; S9. Considering that temperature drift, support stiffness, and grinding wheel wear will cause the model parameters to drift slowly, perform small-step adaptive adjustments to the key parameters online to maintain consistency between removal, force, and displacement, and maintain the upper limit of displacement in step S7. The effectiveness is assessed; gradient-based fine-tuning is employed, with a small step size to ensure convergence, and an implementable update law is provided: ; in , Based on the aforementioned MRR model and reality Calculated; Small step size; for geometric baseline drift caused by wear, based on cumulative removal amount Perform zero bias correction: ; This ensures that the upper bound of the displacement obtained by the force limit mapping is updated consistently with the device state; the above adaptive behavior directly acts on the control law and the conservation boundary: on the one hand, maintaining... The accuracy of the calculation is ensured to avoid long-term over- or under-cutting, and the conversion between force limit and displacement limit is guaranteed to remain valid due to parameter drift, thus avoiding overload and overshoot during long-term operation.

[0017] The present invention achieves the following technical effects compared to the prior art: In the pipe inner circle grinding device of the present invention, multiple wheel-type grinding machines are arranged circumferentially around the central rotating shaft. Driven by the central rotating shaft, the multiple wheel-type grinding machines can simultaneously grind the inner wall of the pipe in all directions. Compared with a single grinding wheel rotating 360° around the inner wall of the pipe, the grinding efficiency can be significantly improved. At the same time, the multiple circumferential wheel-type grinding machines are subjected to reaction forces during the grinding process, which can minimize the eccentricity between the central rotating shaft and the central axis of the pipe, ensure that the grinding wheels of each wheel-type grinding machine exert uniform pressure on the pipe wall, and reduce the problem of local grinding being too deep (overcut) or too shallow (under-grinding) on ​​the inner wall surface, so as to ensure the uniformity and dimensional accuracy of the grinding of the entire inner wall surface. In addition, the pipe inner circle grinding device is equipped with a diameter-changing mechanism, which can adapt to the actual inner wall diameter of the pipe to meet the inner circle grinding needs of pipes with different diameters.

[0018] The other technical solutions of this invention achieve the following technical effects compared to the prior art: 1. In the pipe inner circle grinding device of the present invention, the extension and retraction length of the cylinder piston rod is adjusted by a proportional valve, so that the grinding wheel has an active adjustment function, which improves the grinding adaptability when the inner wall of the steel pipe is uneven. Furthermore, the proportional valve can adjust the pressure of the rod chamber and the rodless chamber of the cylinder, and adjust the pressure in the chamber according to the change of the grinding motor power to achieve constant power grinding of the drive motor, ensuring grinding accuracy and avoiding the problems of grinding too deep (overcutting) or too shallow (undergrinding).

[0019] 2. In the pipe inner circle grinding device of the present invention, a radial floating structure (floating joint bearing and support spring) is set between the drive motor and the grinding wheel, so that the grinding wheel has a certain floating function, which can further improve the grinding adaptability of the grinding wheel when the inner wall of the steel pipe is uneven and reduce the impact caused by the unevenness of the inner wall of the steel pipe. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained by analyzing these drawings without creative effort.

[0021] Figure 1 This is a three-dimensional structural diagram of the pipe inner circle grinding device in an embodiment of the present invention; Figure 2 This is a three-dimensional structural diagram of the pipe inner circle grinding device in an embodiment of the present invention; Figure 3 This is a schematic diagram of the planar structure of the pipe inner circle grinding device in an embodiment of the present invention; Figure 4 This is a schematic diagram of the front end structure of the pipe inner circle grinding device in an embodiment of the present invention; Figure 5 This is a schematic diagram of the rear end structure of the pipe inner circle grinding device in an embodiment of the present invention; Figure 6 This is a three-dimensional structural diagram of the telescopic component in the variable diameter mechanism according to an embodiment of the present invention; Figure 7 This is a front view of the telescopic component in the variable diameter mechanism according to an embodiment of the present invention. Figure 8 This is a schematic diagram of the connection relationship between the motor shaft and the grinding wheel in an embodiment of the present invention; Figure 9 This is a cross-sectional view of the motor shaft and grinding wheel in an embodiment of the present invention.

[0022] Explanation of reference numerals in the attached figures: 1. Central rotating shaft; 2. Variable diameter mechanism; 3. Wheel-type grinder; 101. Bearing end cover; 102. Connecting flange; 201. Central shaft mounting plate; 202. Guide shaft; 203. Guide shaft adapter plate; 204. Cylinder; 205. Cylinder adapter plate; 206. Grinding machine mounting plate; 207. Guide shaft sleeve; 208. Proportional valve; 209. Proportional valve mounting box; 210. Remote controller; 301. Drive motor; 302. Grinding wheel; 303. Cooling nozzle; 304. Cooling fan; 305. Wheel axle; 306. Tool holder; 307. Limiting shaft; 308. Threaded end cap; 309. Floating spherical bearing; 310. Support spring; 311. Drive groove; 312. Spring groove; 313. Motor shaft. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments analyzed and obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] The purpose of this invention is to provide a device and method for grinding the inner circle of a pipe, in order to solve the problems existing in the prior art. Multiple wheel-type grinding machines are arranged circumferentially around the central rotating shaft for synchronous grinding, which can not only improve grinding efficiency, but also reduce the eccentricity of the central shaft, ensure that the pressure of each grinding wheel on the pipe wall is uniform, reduce the problem of local grinding that is too deep (overcut) or too shallow (under-grind) on the inner wall surface of the pipe, improve grinding uniformity and dimensional accuracy, and the diameter-changing mechanism can adapt and adjust according to the actual inner diameter of the pipe to meet the grinding needs of pipes with different diameters.

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Note: The fixed connections mentioned in this article include, but are not limited to, bolt fixing, welding fixing, and adhesive fixing.

[0027] Example 1 like Figures 1 to 9 As shown, this embodiment provides a pipe inner circle grinding device, including a central rotating shaft 1, a diameter-changing mechanism 2, and a wheel grinder 3. The diameter-changing mechanism 2 includes multiple (at least three) telescopic components. The multiple telescopic components are arranged circumferentially along the central rotating shaft 1, wherein the straight lines containing the telescopic directions of adjacent two telescopic components intersect to form an intersection point, and all intersection points can form a regular polygon. The regular polygon has an inscribed circle coaxial with the central rotating shaft 1. The extension direction of all telescopic components deflects clockwise or counterclockwise along the inscribed circle. A wheel grinder 3 is installed at the telescopic end of each telescopic component, and the axis of the grinding wheel 302 of the wheel grinder 3 is parallel to the axis of the central rotating shaft 1. When multiple telescopic components extend or retract synchronously, the wheel-type grinder 3 can be pushed outward or pulled back, thereby increasing or decreasing the radius of the grinding range formed by the grinding wheels 302 of all wheel-type grinders 3, realizing the variable diameter function of the grinding range. This allows for adjustment according to the inner diameter of the pipe, adapting to the inner diameter grinding needs of pipes with different diameters.

[0028] Working principle: In use, the central shaft 1 of the inner circle grinding device for this pipeline (metal pipeline, such as steel pipe) needs to be installed on the drive device. Then, under the drive of the drive device, it extends into the inside of the pipeline, and the central shaft 1 is set coaxially with the pipeline. Then, under the drive of the drive device, the central shaft 1 is driven to rotate, so that the grinding wheels 302 of each wheel grinder 3 revolve around the central shaft 1. Then, the telescopic components of the variable diameter mechanism 2 are extended until the grinding wheels 302 of each wheel grinder 3 contact the pipe wall. During the extension of the telescopic components, the wheel grinder 3 is started, so that the grinding wheels 302 rotate so that they can grind the pipe wall after contact. During the grinding process, the grinding wheels 302 are cooled. Then, under the drive of the drive device, the inner wall of the pipeline is ground. Because this pipe inner circle grinding device has multiple circumferential grinding wheels 3, grinding is performed simultaneously. The central rotating shaft 1 rotates to complete 360° inner circle grinding of the pipe wall. Compared to grinding a single grinding wheel 302 rotating 360° around the pipe wall, the grinding efficiency is significantly improved. Simultaneously, the multiple circumferential grinding wheels 3 experience reaction forces during grinding, which minimizes the eccentricity between the central rotating shaft 1 and the pipe's central axis. This ensures uniform pressure on the pipe wall from each grinding wheel 302, reducing the problem of excessive (over-cutting) or insufficient (under-grinding) grinding on the inner wall surface, thus guaranteeing uniformity and dimensional accuracy of the entire inner wall surface. Furthermore, this pipe inner circle grinding device is equipped with a diameter-adjusting mechanism 2, which adapts to the actual inner diameter of the pipe, thus meeting the needs of grinding pipes of different diameters.

[0029] In one embodiment, a bearing end cover 101 is provided at one end of the central rotating shaft 1 (defined as the front end), and a connecting flange 102 is provided at the other end of the central rotating shaft 1 (defined as the rear end). The connecting flange 102 is connected to the rear drive device by screws to ensure the circumferential movement of the grinding device.

[0030] In one embodiment, each telescopic member has a wheel-type grinder 3 installed at its telescopic end, meaning the number of wheel-type grinders 3 is the same as the number of telescopic members. The grinding wheels 302 of all wheel-type grinders 3 are arranged coplanarly. This ensures that the grinding wheels 302 of all wheel-type grinders 3 are located in the same plane, so that the circular grinding ranges generated by the grinding wheels 302 of all wheel-type grinders 3 completely overlap during their revolution around the central axis 1. The diameter-changing mechanism 2 enables the common circular grinding range of the grinding wheels 302 of the wheel-type grinders 3 to be changed.

[0031] In one embodiment, the diameter-changing mechanism 2 includes three telescopic members, and correspondingly, three wheel-type grinders 3 are provided. The three telescopic members are designed so that the intersection of the telescopic members of the diameter-changing mechanism 2 forms an equilateral triangle. Triangles have extremely high stability, thereby reducing the eccentricity of the central rotating shaft 1 and ensuring that the grinding wheels 302 of each wheel-type grinder 3 exert uniform pressure on the pipe wall, reducing the problem of localized over-grinding (overcutting) or under-grinding (under-grinding) on ​​the inner wall surface. Of course, this does not mean that four, five, or more telescopic members cannot be used.

[0032] In one embodiment, a cooling nozzle 303 is installed on the wheel grinder 3. The cooling nozzle 303 is used to spray cooling gas onto the grinding wheel 302. The cooling nozzle 303 can move forward with the inner circle grinding device of this pipeline, which can match the grinding depth in a timely manner. Compared with external cooling equipment to cool the grinding wheel 302, the following method of the cooling nozzle 303 provides more timely cooling and eliminates the need for an additional drive mechanism. Specifically, the cooling nozzle 303 can be provided with an interface to connect to an external cooling air source.

[0033] In one embodiment, the telescopic component includes a central shaft mounting plate 201, a guide shaft 202, a guide shaft adapter plate 203, a cylinder 204, a cylinder adapter plate 205, a grinder mounting plate 206, and a guide shaft sleeve 207. The central shaft mounting plate 201 is fixedly connected to the central rotating shaft 1, and the axes of the central shaft mounting plate 201 and the central rotating shaft 1 are parallel to each other. The guide shaft adapter plate 203 is fixedly connected to the central shaft mounting plate 201. The guide shaft sleeve 207 is mounted on the guide shaft adapter plate 203. The guide shaft 202 is slidably connected within the guide shaft sleeve 207. Specifically, the guide shaft 202 is sleeved within the guide shaft sleeve 207, and one end of the guide shaft 202 within the guide shaft sleeve 207 is provided with an anti-detachment protrusion. The opening of the guide shaft sleeve 207 is provided with a limiting protrusion. The anti-detachment protrusion and the limiting protrusion cooperate to prevent the guide shaft 202 from detaching from the guide shaft sleeve 207. The cylinder body of cylinder 204 is fixedly connected to guide sleeve 207 via cylinder adapter plate 205. The piston rod of cylinder 204 is arranged parallel to guide sleeve 207 (guide shaft 202). Grinding machine mounting plate 206 is fixedly connected to piston rod of cylinder 204 and guide shaft 202, specifically, the end of guide shaft 202 away from guide sleeve 207 and the end of piston rod of cylinder 204 away from cylinder body are simultaneously fixedly connected to grinding machine mounting plate 206. Wheel grinder 3 is fixedly mounted on grinding machine mounting plate 206. Cylinder 204 is connected to air supply equipment via proportional valve 208. Every two proportional valves 208 form a group, and the three groups of proportional valves 208 respectively operate the three cylinders 204. In each group of proportional valves 208, one supplies / returns air to the rod chamber of cylinder 204, and the other supplies / returns air to the rodless chamber of cylinder 204. The proportional valve 208 can adjust the air supply / return volume and speed to cylinder 204. Driven by gas, the piston rod of cylinder 204 can extend or retract, thereby pushing or pulling back the grinding machine mounting plate 206. Simultaneously, guided by the guide shaft 202 and guide sleeve 207, it works in conjunction with the piston rod of cylinder 204 to ensure the structural stability of the variable diameter mechanism 2. Cylinder 204 can also be replaced by a hydraulic cylinder, electric cylinder, or other telescopic cylinder.

[0034] In one embodiment, a proportional valve mounting box 209 is provided on the central shaft mounting plate 201. The proportional valve 208 is installed inside the proportional valve mounting box 209. Closing the cover of the proportional valve mounting box 209 can enclose the proportional valve 208, preventing debris from splashing onto the proportional valve 208 during the grinding process and causing damage. Two proportional valves 208 are grouped together and installed in one proportional valve mounting box 209.

[0035] In one embodiment, a remote controller 210 is provided on one of the central shaft mounting plates 201, and the remote controller 210 is capable of remotely receiving control signals. The proportional valve 208 and the wheel grinder 3 are both electrically connected to the remote controller 210. The remote controller 210 remotely receives control signals and then controls the proportional valve 208 and the wheel grinder 3. Preferably, the remote controller 210 includes a controller mounting box and control elements, with the control elements installed inside the controller mounting box. This prevents debris from splashing onto the control elements during the grinding process and causing damage.

[0036] In one embodiment, the wheel grinder 3 includes a drive motor 301, a grinding wheel 302, a tool holder 306, a limiting shaft 307, a threaded end cap 308, a floating spherical bearing 309, and a support spring 310. The end of the motor shaft 313 of the drive motor 301 is provided with a drive groove 311. One end of the tool holder 306 is fixedly connected to the wheel axle 305 of the grinding wheel 302, and the other end of the tool holder 306 is mounted in the drive groove 311 via the floating spherical bearing 309. The limiting shaft 307 is coaxially fixedly connected to the end of the tool holder 306 located in the drive groove 311, and the diameter of the limiting shaft 307 is larger than that of the tool holder 306. The threaded end cap 308 is threadedly connected to the end of the motor shaft 313, and the threaded end cap 308 and the limiting shaft 307 sandwich the floating spherical bearing 309 in the middle, axially limiting the floating spherical bearing 309. The limiting shaft 307 is provided with a spring groove 312. One end of the support spring 310 is installed in the spring groove 312, and the other end of the support spring 310 abuts against the groove wall of the drive groove 311, thus supporting the tool holder 306. Under the action of the floating spherical bearing 309 and the support spring 310, the tool holder 306 can float radially, improving the grinding adaptability of the grinding wheel 302 when the inner wall of the steel pipe is uneven.

[0037] In one embodiment, the grinding wheel 302 of the wheel grinder 3 is located near the front end of the central shaft 1, i.e., the bearing end cover 101. The rear end of the drive motor 301 is located near the rear end of the central shaft 1, i.e., near the connecting flange 102.

[0038] In one embodiment, the grinding wheel 302 may be a grinding wheel or the like.

[0039] In one embodiment, the drive motor 301 is fixedly connected to the cylinder adapter plate 205 via a motor mounting base. The cooling nozzle 303 is magnetically attached to the motor mounting base.

[0040] In one embodiment, the drive motor 301 is provided with a cooling fan 304 to cool the drive motor 301.

[0041] This pipe inner circle grinding device has the following advantages: 1. The variable diameter mechanism 2 driven by cylinder 204 enables the grinding device to adapt to different pipe diameters, allowing for efficient and high-precision grinding of the inner circle of metal pipes of varying diameters; 2. The extension and retraction length of the piston rod of cylinder 204 is adjusted by proportional valve 208, giving the grinding wheel 302 an adjustable function and improving its grinding adaptability when the inner wall of the steel pipe is uneven; 3. By setting a floating joint bearing 309 and a support spring 310 between the drive motor 301 and the tool holder 306 of the grinding wheel 302, a radial floating structure is formed between the motor shaft 313 of the drive motor 301 and the grinding wheel 302, giving the grinding wheel 302 a certain floating function, which can further reduce the impact of unevenness in the inner wall of the steel pipe; 4. Each cylinder 204 uses two proportional valves 208 to control the pressure of the rod chamber and the rodless chamber of the cylinder 204 respectively, adjusting the pressure in the chamber according to the power change of the grinding motor to achieve constant power grinding by the drive motor 301. 5. The drive motor 301 directly drives the grinding wheel 302 to perform inner wall grinding. This design can reduce the outer diameter of the grinding wheel 302 and improve the life and stability of the grinding device.

[0042] Example 2 This embodiment provides a method for grinding the inner circle of a pipe, using the pipe inner circle grinding device of Embodiment 1; it includes the following steps: S1. The central shaft 1 is rotated inside the pipe by an external drive (external drive device), thereby driving multiple wheel grinders 3 to rotate around the central shaft 1 inside the pipe. S2. Control the extension of each telescopic component of the diameter-changing mechanism 2 until the grinding wheel 302 of each wheel grinder 3 contacts the pipe wall. During the extension of the telescopic component, start the wheel grinder 3 to make the grinding wheel 302 rotate and cool the grinding wheel 302. Additional cooling equipment can be used for cooling, or the cooling nozzle 303 in Example 1 can be used to cool the grinding wheel 302. During the grinding process, the extension of the telescopic component can be adjusted at any time to adapt to the local unevenness of the inner wall of the pipe. S3. After grinding is completed, control the retraction of each telescopic component to drive the grinding wheels 302 of each wheel grinder 3 to return to their initial state. During the retraction of the telescopic components, the wheel grinder 3 is turned off and the cooling of the grinding wheels 302 is stopped.

[0043] In one embodiment, in step S2, the proportional valve 208 is manipulated by the remote controller 210 to regulate the pressure of the rod chamber and rodless chamber of the cylinder 204, so that the pressure in the rodless chamber of the cylinder 204 is higher than the pressure in the rod chamber. This controls the piston rod of the cylinder 204 to extend, pushing the wheel grinder 3 towards the pipe wall to achieve the diameter change function. The guide shaft 202 and the cylinder 204 move synchronously with the piston rod, jointly ensuring the structural stability of the diameter change mechanism 2. The cylinder drive in the diameter change guide structure can form flexible control, avoiding prolonged overload of the drive motor 301 due to rigid contact during grinding.

[0044] In one embodiment, in step S2, the drive motor 301 is started during the diameter change process, so that the drive motor 301 directly drives the grinding wheel 302 to rotate and starts to provide cooling gas to the cooling nozzle 303 to cool the grinding wheel 302.

[0045] In one embodiment, in step S2, when the grinding wheel 302 contacts the pipe wall, the power of the drive motor 301 of the wheel grinder 3 begins to increase. When the power increases to a set value, the proportional valve 208 in the telescopic component is controlled to maintain the pressure balance between the rod chamber and the rodless chamber of the cylinder 204, thereby achieving constant power control of the drive motor 301. The grinding wheel 302 floats within 5° in the diameter direction to adapt to the unevenness of the pipe wall. In step S3, after grinding is completed, the proportional valve 208 in the telescopic component is controlled to adjust the cylinder 204 so that the pressure in the rod chamber of the cylinder 204 is higher than the pressure in the rodless chamber, thereby controlling the piston rod of the cylinder 204 to retract.

[0046] In one embodiment, an algorithm is used to control the expansion and contraction of the telescopic component. The algorithm's workflow is as follows: S1. Convert the input point cloud data of the area to be polished from a 3D coordinate system to a cylindrical coordinate system, first converting the axial direction... Geometric centering of each cross section The determination; then for any point Define cylindrical coordinates as , where the radius ,angle ; S2. Based on the pitch of the wheel grinder 3, the cylindrical coordinates are helically mapped, transforming the cylindrical coordinate system into a time-domain coordinate system usable for grinding control. The mechanical structure obtains the angular velocity of the grinding unit feed. Axial feed rate Initial phase Initial axial position The angle distribution of the grinding wheel 302 Phase mapping is The grinding curve is mapped to To ensure the consistency of time scale in time-domain data; S3. Sample and discretize the time-domain information. By inputting the axial position, the required grinding amount, the position distribution of the grinding wheel 302, and the upper limit of the maximum allowable normal force of a single grinding wheel 302. Set the grinding amount allocation weight for a single 302 grinding wheel. Perform a share of liability calculation to ensure: ; in Furthermore, constraints need to be set to avoid circumferential and axial stripes. ; Let be the radius of the contact wheel; to avoid single-end overload, based on the conservation of belt volume and the upper limit of normal force, define the first... Head sampling in the axial direction The upper bound of the load-bearing removal capacity is: ; Based on this allocation, the following conditions are met: ; For the objective function chosen as clock priority + load balancing: ; The required parameters can be obtained by applying the above conditions. , Enable command for grinding wheel 302; S4. Axial-grinding amount distribution results Convert to the first Grinding wheel 302 at the sampling position The target normal force and cylinder displacement reference are used as the sole input to the execution layer. The target normal force, obtained by removing the thickness, is transformed into the following relationship: ; in, The pre-calibrated material removal rate coefficient; S5, Target Normal Force The displacement is converted into a traceable reference for the actuator, and a uniform hard upper bound is set in the subsequent shaping. A calibrated quasi-static contact model is adopted: the displacement of cylinder 204 is mapped to the normal compression through the geometric gain of the mechanism. The overall equivalent stiffness characterizes the combined elasticity of the cylinder + mechanism + grinding wheel + workpiece, while considering assembly zero bias and anti-preload; its linear relationship is: ; in To ensure that the direction opposite to the propulsion is positive, the target force is inversely solved as a displacement reference for subsequent shaping: ; in, To achieve zero-biased no-load assembly of the baseline, This is the geometric amplification factor for the cylinder displacement-normal displacement gain; simultaneously, the upper limit of the system force is uniformly mapped to a hard upper limit of displacement. ; Then, a quasi-static push-pressure regression was performed on a standard pipeline. , , ; Combined with known preload At this point, and Closed-form determination; S6. Establish the source and connection relationship of the execution upper limit. The geometric travel upper limit and the force limit → displacement limit jointly determine the allowable displacement upper limit of this sampling point: ; This ensures that subsequent shaping always operates within the dual boundaries of reachable stroke and unexceeded force. Then, the actuator's velocity, acceleration, and Jerk constraints are transformed into discrete difference boundaries to avoid spikes and resonances; equivalently, this is expressed as upper bounds on first-, second-, and third-order differences. , , At each sampling step, the target curve is filtered using cascaded amplitude-limited integrals. The executable reference is as follows: First, limit the jerk to obtain the acceleration, then limit the acceleration to obtain the velocity, and finally integrate to obtain the displacement and trim it to the upper bound, where: , , , ; in Initialization is possible , , ;exist Sections use small Achieve soft entry and exit; then limit the rate of change of force, which can set an upper limit on the force slope. Mapped to the upper limit of the rate of change of displacement, for further suppression of force impact: ; To maintain consistency with the aforementioned time delay modeling, sample advance is adopted. Discrete feedforward compensation is performed in a manner that... To round to the nearest whole number; therefore, the parameter compensation is: , ; S7, for sampling periods of Force error is When there is no power to sense the force error, it is estimated using force estimation. The error is passed through virtual mechanical impedance. Inverse calculation for displacement correction, , , The minimum structure is selected to determine the discrete implementation of response speed and damping. ; Then, according to the upper bound of each head. The trimming process ensures that the force limit → displacement limit constraint and the travel constraint are both uniformly applied: ; Next, we address instantaneous saturation and modal excitation; we convert the clipped displacement error back to the velocity state, ensuring a smooth retreat from the boundary in the next step and avoiding secondary overshoot due to saturation accumulation. ; in The boundary values ​​for this hit are the upper or lower bounds. Backfeedback only takes effect when pruning occurs. ; Then, using the two formulas above, the determined acceleration and Jerk upper limit are directly projected onto the discrete increments, ensuring... The changes in velocity and acceleration will not exceed A shape reference envelope is used to avoid exciting mechanism resonance and reduce surface ripple; S8, In the generation of impedance superposition and limited recharge Subsequently, to close the force loop under no-sensing conditions, a low-cost force estimation method equivalent to the current of the drive motor 301 is adopted, and compared with the force error. Seamless connection, that is use The smallest feasible form of the alternative is: in This is a combined coefficient for the motor force constant and transmission efficiency. This is the no-load current. , Characterizing the static / viscous friction terms respectively, This formula maps the measurable quantities on the drive side to a normal force estimate. The measurable quantities on the drive side include current and velocity, which are used to calculate: ; This allows for the closure of the external force loop without the need for additional force sensors; explicit deduction of the friction term reduces force deviation caused by low-speed stick-slip and suppresses command jitter caused by estimation noise; in position measurement Superimposed first-order perturbation observations (ESO) Make minor corrections to enhance robustness in load transition scenarios.

[0047] S9. Considering that temperature drift, support stiffness, and wear of the 302 grinding wheel will cause the model parameters to drift slowly, small-step adaptive adjustments are made to the key parameters online to maintain consistency between removal, force, and displacement, and to maintain the upper limit of displacement in step S7. The effectiveness is assessed; gradient-based fine-tuning is employed, with a small step size to ensure convergence, and an implementable update law is provided: ; in , Based on the aforementioned MRR model and reality Calculated; Small step size; for geometric baseline drift caused by wear, based on cumulative removal amount Perform zero bias correction: ; This ensures that the upper bound of the displacement obtained from the force limit mapping is updated consistently with the device state. The aforementioned adaptive behavior directly acts on the control law and the conservation boundary: on the one hand, it maintains... The accuracy of the calculation is ensured to avoid long-term over- or under-cutting, and the conversion between force limit and displacement limit is guaranteed to remain valid due to parameter drift, thus avoiding overload and overshoot during long-term operation.

[0048] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A device for grinding the inner circle of a pipe, characterized in that, The device includes a central rotating shaft, a diameter-changing mechanism, and a wheel-type grinder. The diameter-changing mechanism includes telescopic members arranged circumferentially along the central rotating shaft. The straight lines containing the telescopic directions of two adjacent telescopic members intersect to form an intersection point. All intersection points can form a regular polygon. The regular polygon has an inscribed circle coaxial with the central rotating shaft. The extension direction of all telescopic members deflects clockwise or counterclockwise along the inscribed circle. The wheel-type grinder is installed at the telescopic end of each telescopic member. The axis of the grinding wheel of the wheel-type grinder is parallel to the axis of the central rotating shaft.

2. The pipe inner circle grinding device according to claim 1, characterized in that, Each of the telescopic components has a wheel-type grinder installed at its telescopic end, and the grinding wheels of each wheel-type grinder are arranged on the same plane.

3. The pipe inner circle grinding device according to claim 1, characterized in that, The diameter-changing mechanism includes three telescopic components.

4. The pipe inner circle grinding device according to claim 1, characterized in that, The wheel grinder is equipped with a cooling nozzle, which is used to spray cooling gas onto the grinding wheel.

5. The pipe inner circle grinding device according to any one of claims 1-4, characterized in that, The telescopic component includes a central shaft mounting plate, a guide shaft, a guide shaft adapter plate, a cylinder, a cylinder adapter plate, and a grinder mounting plate. The central shaft mounting plate is fixedly connected to the central rotating shaft. The guide shaft adapter plate is fixedly connected to the central shaft mounting plate. A guide shaft sleeve is provided on the guide shaft adapter plate. The guide shaft is slidably connected to the guide shaft sleeve. The cylinder body is fixedly connected to the guide shaft sleeve through the cylinder adapter plate. The piston rod of the cylinder is arranged parallel to the guide shaft sleeve. The grinder mounting plate is fixedly connected to the piston rod of the cylinder and the guide shaft. The wheel grinder is fixedly mounted on the cylinder. The cylinder is connected to the air supply equipment through a proportional valve.

6. The pipe inner circle grinding device according to claim 5, characterized in that, One of the central shaft mounting plates is equipped with a remote controller capable of remotely receiving control signals, and the proportional valve and the wheel grinder are both electrically connected to the remote controller.

7. The pipe inner circle grinding device according to any one of claims 1-4, characterized in that, The wheel grinder includes a drive motor, a grinding wheel, a handle, a threaded end cap, a floating spherical bearing, and a support spring. The end of the motor shaft of the drive motor is provided with a drive groove. One end of the handle is fixedly connected to the axle of the grinding wheel, and the other end of the handle is installed in the drive groove through the floating spherical bearing. The end of the handle located in the drive groove is provided with a limiting shaft, the diameter of which is larger than that of the handle. The threaded end cap is threaded to the end of the motor shaft. The threaded end cap and the limiting shaft clamp the floating spherical bearing in the middle. The limiting shaft is provided with a spring groove, one end of which is installed in the spring groove, and the other end of which abuts against the groove wall of the drive groove.

8. A method for grinding the inner circle of a pipe, characterized in that, The pipe inner circle grinding device as described in any one of claims 1-7 is used; the process includes the following steps: S1. The central shaft is rotated inside the pipe by an external drive; S2. Control the extension of each telescopic component of the diameter-changing mechanism until the grinding wheel of each wheel grinder contacts the pipe wall. During the extension of the telescopic components, start the wheel grinder to make the grinding wheel rotate and cool the grinding wheel. S3. After grinding is completed, control the retraction of each telescopic component to drive the grinding wheels of each wheel grinder back to their initial state. During the retraction of the telescopic components, the wheel grinder is turned off and the cooling of the grinding wheels is stopped.

9. The method for grinding the inner circle of a pipe according to claim 8, characterized in that, In step S2, when the grinding wheel contacts the pipe wall, the power of the drive motor of the wheel grinder begins to increase. When the power increases to a set value, the proportional valve in the telescopic component is controlled to maintain the pressure balance between the rod chamber and the rodless chamber of the cylinder, thereby achieving constant power control of the drive motor. The grinding wheel floats within 5° in the diameter direction to adapt to the unevenness of the pipe wall. In step S3, after grinding is completed, the proportional valve in the telescopic component is controlled to adjust the cylinder so that the pressure in the rod chamber of the cylinder is higher than the pressure in the rodless chamber, thereby controlling the piston rod of the cylinder to retract.

10. The method for grinding the inner circle of a pipe according to claim 9, characterized in that, An algorithm is used to control the expansion and contraction of the telescopic component. The algorithm's workflow is as follows: S1. Convert the input point cloud data of the area to be polished from a 3D coordinate system to a cylindrical coordinate system, first converting the axial direction... Geometric centering of each cross section The determination; then for any point Define cylindrical coordinates as , where the radius ,angle ; S2. Based on the pitch of the wheel grinder, the cylindrical coordinate system is helically mapped to a time-domain coordinate system that can be used for grinding control. The mechanical structure obtains the angular velocity of the grinding unit feed. Axial feed rate Initial phase Initial axial position Angle distribution of the grinding wheel Phase mapping is The grinding curve is mapped to To ensure the consistency of time scale in time-domain data; S3. Sample and discretize the time-domain information. By inputting the axial position, the required grinding amount, the grinding wheel position distribution, and the maximum allowable normal force of a single grinding wheel. Set the weight of grinding amount allocation for a single grinding wheel. Perform a share of liability calculation to ensure: ； in Furthermore, constraints need to be set to avoid circumferential and axial stripes. ; Let be the radius of the contact wheel; to avoid single-end overload, based on the conservation of belt volume and the upper limit of normal force, define the first... Head sampling in the axial direction The upper bound of the load-bearing removal capacity is: ； Based on this allocation, the following conditions are met: ； For the objective function chosen as clock priority + load balancing: ； The required parameters can be obtained by applying the above conditions. , Enable command for grinding wheel; S4. Axial-grinding amount distribution results Convert to the first Grinding wheel at sampling position The target normal force and cylinder displacement reference are used as the sole input to the execution layer. The target normal force, obtained by removing the thickness, is transformed into the following relationship: ； in, The pre-calibrated material removal rate coefficient; S5, Target Normal Force The displacement is converted into a traceable reference for the actuator, and a uniform hard upper bound is set in subsequent shaping. A calibrated quasi-static contact model is adopted: the cylinder displacement is mapped to the normal compression through the mechanism's geometric gain. The overall equivalent stiffness characterizes the combined elasticity of the cylinder, mechanism, grinding wheel, and workpiece, while considering assembly zero bias and anti-preload; its linear relationship is: ； in To ensure that the direction opposite to the propulsion is positive, the target force is inversely solved as a displacement reference for subsequent shaping: ； in, To achieve zero-biased no-load assembly of the baseline, This is the geometric amplification factor for the cylinder displacement-normal displacement gain; simultaneously, the upper limit of the system force is uniformly mapped to a hard upper limit of displacement. ； Then, a quasi-static push-pressure regression was performed on a standard pipeline. , , ; Combined with known preload At this point, and Closed-form determination; S6. Establish the source and connection relationship of the execution upper limit. The geometric travel upper limit and the force limit → displacement limit jointly determine the allowable displacement upper limit of this sampling point: ； This ensures that subsequent shaping always operates within the dual boundaries of reachable stroke and unexceeded force. Then, the actuator's velocity, acceleration, and Jerk constraints are transformed into discrete difference boundaries to avoid spikes and resonances; equivalently, this is expressed as upper bounds on first-, second-, and third-order differences. , , At each sampling step, the target curve is filtered using cascaded amplitude-limited integrals. The executable reference is as follows: First, limit the jerk to obtain the acceleration, then limit the acceleration to obtain the velocity, and finally integrate to obtain the displacement and trim it to the upper bound, where: ， ， ， ； in Initialization is possible , , ;exist Sections use small Achieve soft entry and exit; then limit the rate of change of force, which can set an upper limit on the force slope. Mapped to the upper limit of the rate of change of displacement, for further suppression of force impact: ； To maintain consistency with the aforementioned time delay modeling, sample advance is adopted. Discrete feedforward compensation is performed in a manner that... To round to the nearest whole number; therefore, the parameter compensation is: , ; S7, for sampling periods of Force error is When there is no power to sense the force error, it is estimated using force estimation. The error is passed through virtual mechanical impedance. Inverse calculation for displacement correction, , , The minimum structure is selected to determine the discrete implementation of response speed and damping. ； Then, according to the upper bound of each head. The trimming process ensures that the force limit → displacement limit constraint and the travel constraint are both uniformly applied: ； Next, we address instantaneous saturation and modal excitation; we convert the clipped displacement error back to the velocity state, ensuring a smooth retreat from the boundary in the next step and avoiding secondary overshoot due to saturation accumulation. ； in The boundary values ​​for this hit are the upper or lower bounds. Backfeedback only takes effect when pruning occurs. ； Then, using the two formulas above, the determined acceleration and Jerk upper limit are directly projected onto the discrete increments, ensuring... The changes in velocity and acceleration will not exceed A shape reference envelope is used to avoid exciting mechanism resonance and reduce surface ripple; S8, In the generation of impedance superposition and limited recharge Subsequently, to close the force loop under no-sensor conditions, a low-cost force estimation method equivalent to the drive motor current is adopted, and this is compared with the force error. Seamless connection, that is use The smallest feasible form of the alternative is: in This is a combined coefficient for the motor force constant and transmission efficiency. This is the no-load current. , Characterizing the static / viscous friction terms respectively, This formula maps the measurable quantities on the drive side to a normal force estimate. The measurable quantities on the drive side include current and velocity, which are used to calculate: ； This allows for the closure of the external force loop without the need for additional force sensors; explicit deduction of the friction term reduces force deviation caused by low-speed stick-slip and suppresses command jitter caused by estimation noise; in position measurement Superimposed first-order perturbation observations (ESO) Make minor corrections to enhance robustness under load transition scenarios; S9. Considering that temperature drift, support stiffness, and grinding wheel wear will cause the model parameters to drift slowly, perform small-step adaptive adjustments to the key parameters online to maintain consistency between removal, force, and displacement, and maintain the upper limit of displacement in step S7. The effectiveness is assessed; gradient-based fine-tuning is employed, with a small step size to ensure convergence, and an implementable update law is provided: ； in , Based on the aforementioned MRR model and reality Calculated; Small step size; for geometric baseline drift caused by wear, based on cumulative removal amount Perform zero bias correction: ； This ensures that the upper bound of the displacement obtained by the force limit mapping is updated consistently with the device state; the above adaptive behavior directly acts on the control law and the conservation boundary: on the one hand, maintaining... The accuracy of the calculation is ensured to avoid long-term over- or under-cutting, and the conversion between force limit and displacement limit is guaranteed to remain valid due to parameter drift, thus avoiding overload and overshoot during long-term operation.

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